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Über dieses Buch

Proceedings of the FISITA 2012 World Automotive Congress are selected from nearly 2,000 papers submitted to the 34th FISITA World Automotive Congress, which is held by Society of Automotive Engineers of China (SAE-China ) and the International Federation of Automotive Engineering Societies (FISITA). This proceedings focus on solutions for sustainable mobility in all areas of passenger car, truck and bus transportation. Volume 8: Vehicle Design and Testing (II) focuses on:

•Automotive Reliability Technology

•Lightweight Design Technology

•Design for Recycling

•Dynamic Modeling

•Simulation and Experimental Validation

•Virtual Design, Testing and Validation

•Testing of Components, Systems and Full Vehicle

Above all researchers, professional engineers and graduates in fields of automotive engineering, mechanical engineering and electronic engineering will benefit from this book.

SAE-China is a national academic organization composed of enterprises and professionals who focus on research, design and education in the fields of automotive and related industries. FISITA is the umbrella organization for the national automotive societies in 37 countries around the world. It was founded in Paris in 1948 with the purpose of bringing engineers from around the world together in a spirit of cooperation to share ideas and advance the technological development of the automobile.

Inhaltsverzeichnis

Frontmatter

Automotive Reliability Technology

Frontmatter

Vehicle Usage Measurement and Analysis Based on the Random Retail Customer

Customer vehicle real world usage is one of the most important foundations of vehicle development. It is the basis of setting vehicle, subsystem and component technical specification; the basis of developing product validation test procedure; the basis of product evaluation target. On the other hand, it is also the basis of product warranty system. This chapter introduces a random customer vehicle real world usage measurement and analysis method which is found on statistical sampling theory, vehicle CAN and signal measurement technical.

Yaozeng Pan, Feng Yang, Chenyang Li

Lightweight Design Technology

Frontmatter

Design, Evaluation Methods and Parameters of Automotive Lightweight

Automotive lightweight is quite important and active demand, due to the requirements of automotive industry development, energy saving and emission reduction. This chapter illuminates the signification, the conception and comprehension, characterization parameters and execution methods about automotive lightweight and lightweight design. The physical and technical signification of parameters in the lightweight coefficient equation is explained also. A more direct parameter, lightweight exponent L

i

is suggested, and the physical and technique significations of those parameters in lightweight exponent L

i

equation are clarified for various conditions of lightweight. The execution approaches of automotive lightweight and the relationship of the performance of typical parts with the performance of materials are discussed. A life cycle analysis method is presented to evaluate the economy, selection and application of the lightweight materials and technologies.

Mingtu Ma, Hongzhou Lu

Body Light Weight and Cost Control

Body light weight is optimization design of body performance under body cost control, which is also a system engineering balanced body performance and body cost. Making the best of application of computer aided software for design and analysis, contrast body performance is sensitive to steel thickness, carry through light weight design and cost control, combine application these methods: body structure optimization included body joints optimization, major section improvement and features betterment; using more thin steel with higher strength as advanced high strength steel, ultra high strength steel, even press hardened steel; using new kind of light material as plastic, various alloy; applying new manufacture process as TRB, TWB, hot stamping etc. Controlling body cost through these methods such as, body structure boundary well adjusted in order to improve material utilization ratio, removing those overmuch strength structure, using low price material with equal performance. Applying computer aided software, carried through system design and analysis, balanced advantage and disadvantage of these methods, can we realize the aim of body light weight and cost control. Researching and discovering body light weight has sameness with body cost control, but there are also some differences, because both of their purpose and method are different. At present, costliness of those advanced light material with higher strength is the developing bottle neck for vehicle bodywork light weight and body cost control. Only when more cheap materials with high strength appear, can automobile company farther realize reducing body weight and low cost body.

Dazhou Guo

Lightweight Design and Formability Analysis of Auto Body Aluminum Trunk Lid

Aluminum-alloy achieves more application in automobile industry as a kind of lightweight material. Auto body structures experience complex loads and performance requirements differ greatly among these conditions. In order to integrate all mechanical properties into initial design of Aluminum-alloy structure, a new optimization method is provided. With the prototype of a steel trunk lid, a new design based on original structure space using material replacement, structure optimizing and formability validation method is put forward. New Aluminum-alloy trunk lid matches both the performance and manufacturability requirement with weight reduction of 41.6 %. This method provides a referable way for lightweight deign of aluminum-alloy trunk lid in initial design phase.

Zhao Liu, Ping Zhu, Xiaojing Zhu

Geometric Parameters Optimal Design of Variable Cross-Section Rim

In order to achieve the wheels lightweight design, the optimization software Isight integrated with SolidWorks and Abaqus. The parametric three-dimensional model of the rim section is built based on SolidWorks, the finite element method is used to analyze stress and displacement distributions in a variable cross-section rim subject to the conjoint influence of radial load and inflation pressure. The optimization methods which combined multi-island genetic algorithm (MIGA) with NLPQL algorithm is used for exploration. By adjusting control parameters of the rim shape quality is optimized. The results show that the optimization effect is good.

Hongyu Wang

Lightweight Design for a FSC Car Based on Modal and Stiffness Analysis

Based on the stiffness and vibration modal analysis for a FSC racing car frame with the FEA method and testing evaluation, the design parameters of optimal tubular space frame were determined through the sensitivity analysis. Oriented the minimizing the frame weight, the thickness of tubes was conducted under meet the requirements of stiffness and vibration modal. As a result, the frame weight was deceased by 7.18 %.

Liman Jiang, Guoquan Wang, Guoqing Gong, Ruiqian Zhang

Application of Comprehensive Optimization into Bus Structure Lightweight Improvement in 3-Section Chassis Frame

This chapter presents the structural optimization and lightweight design of a bus chassis frame. Firstly, the static performance of the chassis frame is obtained using finite element analysis (FEA). A prototype of a chassis truss divided into three-sections is proposed based on the material distribution from the topology optimization. Comparative analysis between the optimized chassis structure and the original structure shows that the optimal chassis is superior to the original in terms of the rigidity, strength and mode performance. Compared to the results for the original frame, the maximum stress of the optimized chassis truss under the worst torsional loading case are reduced 23.4 MPa, the maximum stiffness increased 18.5 %. Moreover, a mass-saving with 196 kg, i.e., 14 % of the original chassis mass verifies the lightweight design performed in this study.

Congcheng Ma, Fengchong Lan

Applying Agile Software Principles and Practices for Fast Automotive Development

This paper addresses lightweight designs both in terms of materials and processes. The study is based on the WIKISPEED SGT01 car, which was an entrant in the Progressive Insurance Automotive X-Prize contest to produce a full-sized road-legal car getting 100+ mi/gal (2.25 L/100 km). The 638 kg car is built from aluminum and composites. Agile Methods were introduced for software projects and give product cycle times measured in weeks, not years. Good software design demands modules that are loosely coupled and can be tested apart from the entire system. These principles have led to a modular automotive design. On the WIKISPEED car, major subassemblies such as suspension, motor, and body can be replaced in the time it takes to change a flat tire. The wheels and suspension bolt to the chassis and can be repositioned or replaced. The composite body bolts to the chassis and allows exchange of external shells. The same car can be a race car today and a pick-up truck tomorrow. This modularity allows for rapid iterations and experimentations during development, testing, and after purchase. A mid-engine design ensures that the center of gravity is well-positioned no matter what engine is used. Production does not use metal stamping, molds, or autoclaves.

David Socha, Tyler C Folsom, Joe Justice

Multi-Objective Evaluation Regulation Study of Automotive Lightweight

Based on the multi-objective optimization and design of automotive body, the evaluation method of automotive lightweight is studied. An innovative evaluation method and the automotive lightweight comprehensive evaluation index E are presented, which is expressed by following formula

$$ {\text{E}} = \frac{{{\text{m}}_{{{\text{body}}}} }}{{{\text{C}}_{{\text{t}}} \, \times \,{\text{A}}\, \times \,\left[ {{\text{ENCAP}}} \right]\, \times \,{\text{F}}}}\left[ {\frac{{{\text{kg}}}}{{{\text{Nm}}/^{^\circ } \, \times \,{\text{m}}^{2} \, \times \,{\text{Hz}}}} \times 10^{4} } \right] $$

, and the weight of car body is associated with the model, stiffness of car body and safety of cars by this formula. The relationship between automotive lightweight and correlative functions is discussed. The evaluation method is confirmed by applying the data of 14 typical passenger cars. The relationship between evaluation index E and relational parameters are discussed, and some comparison and analysis are carried out, the sensitivity of E value for varying of relational parameters values is demonstrated, and the sensitivity is acceptable. And according to the E value, the lightweight level of a car can be defined, which is from 1 to 5 stars. A requirement of integrated fuel consumption for lightweight star level based on car mass is presented to be as a modifier to modify the final star-rating results of a car. This evaluation regulation considers the modal, stiffness, and sizes of car body, and safety of cars, and fuel consumption which are associated with weight of car body and car mass. A conclusion is attained that the evaluation method of lightweight presented by this paper is feasible, however, the details of evaluation regulation of automotive lightweight will be studied further, and an official new car evaluation regulation of automotive lightweight will be presented. According to the evaluation results and stars rating, customers can choose to buy a more lightweight and energy-saving car. And based on the stars rating, governments can also improve energy saving and emission reduction of automotive industry, by encouraging the car makers which produce the lightweight cars.

Hongzhou Lu, Zhiwen Wang, Ma Mingtu, Yilong Cheng, Guimin Lu

Future Mobility Requires Advanced Car Concepts and Power Train

Research and/or Engineering Questions/Objective

Mobility is essential for well performing economy. One Billion vehicles are on the road globally. In 20 years the fleet is estimated to double. Global crude oil demand and prices are growing. To secure economy by well performing mobility there are only two main routes to go. (1) Broader range of different power train. (2) Energy Efficiency Measures. Besides power train efficiency the curb weight reduction is an effective solution applicable for all energy and vehicle types. In 2007 Evonik Industries started to evaluate a variety of polymers and material concepts for different automotive applications. The variety of polymers, reinforcement fibres, core materials and processes represent a huge number of potential solutions competing with established materials. On the other hand this complexity is an excellent opportunities for cost effective parts. Applying new composite material technologies also offer new design options such as large and complex body parts manufactured in “one shot”.

Methodology

All existing and coming up material concepts, different production processes of those and different applications for automotive serial application were studied. The Target was to find out the best combination relating cost, performance and weight reduction potential. The material concepts were proofed under severe conditions on the race track and in parallel with a road approved car.

Results

The factors weight reduction, performance, costs and annual production volume of lightweight parts were evaluated in detail to meet automotive targets. In this process Sandwich Composite Bodywork and Polymer Glazing were identified as promising future applications of novel material concepts. For automotive application new efficient processes have to be developed with adjusted chemistry to meet automotive quality and serial volume capability.

Limitations of This Study

Evonik is supporting the new process technology developments for the new material concepts in co-operations. The developments are highly confidential and cannot be disclosed.

What does the Paper Offer That is New in the Field in Comparison to Other Works of the Author

The paper includes the potential of polymer lightweight material concepts and the gaps to be closed to succeed for automotive serial application. The paper shows very promising routes and also the very fast testing of those routes at demonstration cars.

Conclusion

To demonstrate the feasibility two sport cars were built with Evonik material concepts. Features are light weight body, polymer screens, friction reduced engine oil, low weight and rolling resistant tires and additional measures. This electric powered demonstration car achieves a better balance of performance, range and cost by development and application of new material concepts. In comparison to the Tesla the Evonik E-Elise is 255 kg lighter and has 3/5 of battery capacity.

Sven Augustin

A Lightweight Optimization Method of Vehicle Body Structure Design

Lightweight body is effective for reducing the concentration of pollutant in emissions, improving crashworthiness performance and dynamic performance. Lightweight Index, which is proportional to body mass and inversely proportional to torsion stiffness, is used to evaluate the lightweight degree of body structure. Lightweight index can be reduced according to increasing torsion stiffness and reducing mass. The calculation of body stiffness is a linear process, which can be simulated by finite element analysis with high precision. In this paper, the torsion stiffness of a vehicle body was studied by using CAE analysis software. After simulation, the lightweight index was calculated according to body mass and torsion stiffness. For the purpose of improving lightweight index, body structure should be optimized to improve torsion stiffness and decrease body weight. At first, using sensitivity analysis, this paper studied the influence of 50 main parts’ gauge to torsion stiffness and body weight, these parts thickness were set as variables in optimization. Then, after optimization, by comparing sensitivities of torsion stiffness and body weight, this paper identified key parts of a car body, according to optimizing the gauges of parts, the body weight decreased 3.1 kg, while torsion stiffness increased 38 Nm/deg. Comparing with part thickness, part structure has greater affection to the stiffness property, topography optimization can be used to optimize the design of part structure and shape. In this paper, coat rack structure was studied, through topography optimization to find the best optimized structure with manufacturing requirement. Vehicle parts are designed not only considering stiffness performance, but also taking into account strength, crashworthiness, NVH performance and so on, only body torsion stiffness for study has limitation. Topography optimization can only find optimal part structure, however, manufacturing costs and feasibility should be considered. In this paper, CAE software tools were used to perform sensitivity analysis and optimization, parts gauges were set as variables to optimize body stiffness and weight, and topography optimization was used to optimize rib structure and position of coat rack, which gave a simple way to lightweight body design and optimize.

Zhixiang Li, Jifa Mei

Analysis of the Transient Thermomechanical Behaviour of a Lightweight Brake Disc for a Regenerative Braking System

Regenerative braking would extend the working range of an EV or HV provided that any extra energy consumption from increased vehicle mass and system losses did not outweigh the saving from energy recuperation, also reduce duty levels on the brakes themselves, giving advantages including extended brake rotor and friction material life, but more importantly reduced brake mass, minimise brake pad wear. The objective of this research is to define thermal performance on lightweight disc brake models. Thermal performance was a key factor which was studied using the 3D model in FEA simulations. Ultimately a design method for lightweight brakes suitable for use on any car-sized hybrid vehicle was used from previous analysis. The design requirement, including reducing the thickness, would affect the temperature distribution and increase stress at the critical area. Based on the relationship obtained between rotor weight, thickness, undercut effect and offset between hat and friction ring, criteria have been established for designing lightweight brake discs in a vehicle with regenerative braking.

S. Sarip, A. J. Day, P. Olley, H. S. Qi

Concept Analysis of Automotive Aluminium Alloy Bumper

One style of aluminium alloy bumper was developed for a passenger car. Firstly, strength performance objective was obtained through three-point static pressure simulation analysis and test on steel bumper of a target vehicle. In order to provide reference for aluminium alloy bumper on the design of structure and performance, benchmark analysis was applied on a reference aluminium alloy bumper. Then, the cross-section shape and dimension parameters of aluminium alloy bumper of target vehicle were obtained with OptiStruct topology optimization and size optimization, so that the material, process method and processing parameters of components of the production can be determined, among which, 6,061 aluminium alloy was employed for producing bumper beam with hot extrusion process, and 6,101 aluminium alloy was employed for producing crash box and flange with hot extrusion process. At last, low-speed collision simulation and test were used to analyze the energy absorption capacity of steel and aluminium alloy bumper. It has been found that: in the process of head-on collision, the energy absorption of aluminium alloy bumper is higher than that of steel bumper with increasing 5 %; the absorption per unit mass of aluminium bumper is significantly greater than that of steel bumper, and its deformation is 110 mm less than the permission displacement. Consequently, it is concluded that the crashworthiness of aluminium alloy is better than that of steel bumper. In this paper, an aluminium alloy bumper was designed by using topology optimization and size optimization method, which has better performance, compacter structure and lighter weight than that of steel bumper. However, in view of the complexity of the actual working conditions applied by bumper, higher requirements should be taken into account in design process. Therefore, in subsequent structural optimization research, integration of additional conditions needs to be considered, such as collision, etc.

Xinming Wan, Xiao Zhi, Qingjiang Zhao, Guangyao Wang, Xiaofei Xu

Study on Lightweight of Vehicle Body Structure Based on Implicit Parametric Model

In the early development phase of a passenger car, the implicit parametric model of the lower body of BIW was built by SFE CONCEPT and combined with the finite element model of other parts of BIW to compose the parametric BIW model. On an Optimus workflow including BIW stiffness and vibration mode, design variables and their effective range were defined based on engineering experiences and vehicle features. A Response Surface Model (RSM) was created through Design of Experiments (DOE), and effects of key parameters of BIW structure on the stiffness and vibration mode were analyzed. Finally global optimization was conducted, and the lightweight vehicle body structure in compliance with performance requirements of modal and stiffness purposes was obtained, which saved 11.35 kg (154.55 → 143.20 kg) and lightweight effect was 7.34 %.

Jiyou Zhang , Shudan Liu, Hong Peng, Yongxin Men, Fuquan Zhao

Lightweight Design and Evaluation for Cab-in-White of Heavy-Duty Truck

The weight of a heavy-duty-truck is one of the most important indexes to evaluate the lightweight design level of the cab. The domestic heavy-duty-truck studied in this chapter is high-roof with one and a half seat space, which is overweight by 10 % compared with the same type of truck aboard. In order to reduce vehicle weight, improve fuel economy, the lightweight design of the cab is carried out. In this chapter, topology optimization and size optimization methods are applied to realize the lightweight design for the cab-in-white of a heavy-duty-truck, and the weight is reduced by 46 kg. Next, the comparative analysis show that the strength, stiffness and the natural vibration characteristics of lightweight designed cab are essentially the same with the original, and the passive safety meets ECE R29 regulatory requirements. On this basis, this chapter proposes the lightweight coefficient of the cab-in-white of a heavy-duty-truck as a evaluation index for lightweight design, used in the lightweight analysis and evaluation for cab-in-white of a heavy-duty-truck.

Xinyu Wang, Dengfeng Wang, Wanlai Sun, Peiwu Liu

Research on Parameterized Structural Modeling for Carbody Lightweighting

The method of parameterized structural modeling and design based on SFE CONCEPT makes it is available for fast modification and multi-performance rapid integration optimization on carbody structure. A structural SFE model is built from a car structural FE model in concept development stage, which is validated by some design simulation data. The validated SFE structural model can be used for rapid optimization and multi-performance evaluation for different design variation. This engineering parameterized design method on carbody structure has the obvious practical advantage to improve the efficiency of lightweighting design.

Xin Chen, Fangwu Ma, Dengfeng Wang, Yongxin Men, Qiang Liu, Zaiqi Yao, Junlong Zhou, Chen Xie

Reliability-Based Topology Optimization of Control Arm of Suspension for Lightweight Design

The existing uncertainties and the inducing factors for control arm are presented under the position of its function and requirements. Reliability-based topology optimization is proposed that integrate reliability analysis into topology optimization to design control arm subject to random inputs, such as random external loads. A singe loop method is implemented to consider the reliability levels by combination deterministic topology optimization software. The first-order reliability method is adopted to approximate the failure probability constraint at most probable point. The random variables are transformed into deterministic boundary conditions for topology optimization by reliability index approach. Optimal topologies of control arm obtained from reliability-based topology optimization are compared to result from traditional deterministic topology optimization.

Qinghai Zhao, Xiaokai Chen, Yi Lin

Structural Lightweight Design of Engine Connecting Rod

The connecting rod is one of the key components of an automotive engine; it works under dynamic loads with complex uncertainties. The reliability of a connecting rod is critical for an engine design. For traditional deterministic numerical simulations of connecting rods, which neglect some uncertain factors, the reliability is guaranteed by introducing overly conservative safety factors, and it normally results in a safe but over weighted and suboptimal design. In this paper a framework for the sensitivity analysis and reliability based design optimization of a connecting rod is proposed. The most advanced reliability based design optimization and simulation software integration methods will be employed in this research; it seamlessly integrates a sensitivity and reliability analysis driver, a parameter driven CAD tool, and an advanced nonlinear structural analysis CAE software package. The entire process will be conducted automatically by command scripts. Using the proposed reliability based analysis framework the weight of the connecting rod is reduced by 3.7 % without compromising reliability.

Fuxiang Huo, Jun Li, Yu Xu, Bing Wu, Yepeng Han, Peng Li, Qun Zhang

Design for Recycling

Frontmatter

Development of Environmental Assessment System of Vehicle

Vehicles can lead to the environmental impact throughout their whole life cycle—from production, use, to disposal. Therefore, analyzing the whole life’s environmental profile and setting up advanced environmental performance target for each vehicle within vehicle development process is the basis of ‘Eco-design’. In this respect, Life Cycle Assessment (LCA) is a useful tool for analyzing the environmental profile. However, it is very time and manpower consuming work to collect and process the huge amounts of data related to material and energy flows during whole life cycle of a vehicle in the LCA process, due the number of components that a vehicle is made from. Therefore, environmental assessment system of vehicle is developed by GM Korea Company to help manage this problem based on automated and standardized data management and processing methods.

Moosang Yu, Yunjong Kim

Research on Hydraulic Regenerative Braking System for Pure Electric Vehicle Based on AMESim

In order to increase the regenerative braking energy recovery and the dynamic performance of vehicle, the hydraulic braking energy recovery system is confirmed to use with the storage battery braking energy recovery system after comparing kinds of regenerative braking recovery plan and energy storage methods. Through PID control, simulation under ECE-15 cycle working mode and analysis of vehicle dynamic performance and energy recovery efficiency are conducted. The system simulation and analysis results show that using hydraulic regenerative braking system in pure electric vehicle can significantly improve the ability of vehicle’s start-acceleration and the increase in vehicle driving range reaches around 28 %.

Junping Jiang, Xiaobin Ning, Yaoting Xu, Qiucheng Wang, Wei Liu, Zhijie Pan, Fuquan Zhao

Dynamic Modeling

Frontmatter

Main Problems of Creating Surface Traction-Transport Vehicles with Mechatronic Systems

The article enumerates the main problems encountered in creating main traction-transport vehicles (TTV) units as mechatronic systems. The authors review the results of the comprehensive theoretical and experimental studies of creating TTVs—automobiles and tractors of the future based on mechatronic systems. The analysis of the results shows that TTV progress is only possible based on a broad introduction of mechatronic modules into vehicle designs. This significantly increases the role of electronics and control systems.

Belousov Boris, Ksenevich Tatiana

Wheelbase Filtering Effect on Vehicle Ride Dynamics

The time delay of rear wheel input relative to front one acts to filter the amplitude of vehicle motion. Through reference to a half-car pitch plane model, mechanism of wheelbase filtering was investigated. Amplitude of FRF between a motion and road input could be divided into two parts: steady part and variable part. Steady part that is determined by natural property of vehicle does not change with outer input condition. However, variable part fluctuates frequently because of cosine function item of itself, which is closely related to velocity of vehicle. It is variable part that modulates the amplitude of vehicle motion. In addition, wheelbase filtering effect varies greatly at different locations on the body. Filtering effect on work space and dynamic tire load of suspension was also studied. Results show that rear road input hardly influences front suspension motion and vice versa, so variable part is much smaller than steady part and filtering effect in suspension motion is not obvious.

Kang Song, Xiaokai Chen, Yi Lin

Simulation and Experimental Validation

Frontmatter

Modeling and Experimental Research About a New Type of Vehicle Active Suspension Electromagnetic Actuator

A new type of electromagnetic linear actuator for vehicle active suspension was designed, with the characteristics of large stroke and force and fast response. Combined with the finite element analysis software, the effects of actuator structure parameters such as gap thickness, the secondary stainless steel thickness, the secondary copper thickness, permeability and conductivity of insulation stall on actuator thrust size and speed response were studied. And the effects of actuator power parameters such as voltage, frequency and load mode on actuator thrust size and speed response were also studied. The results show that the electromagnetic force is closely related to structural parameters such as the gap thickness, except for the conductivity of insulation stall. And the electromagnetic force is proportional to the square of the voltage, and first increases and then decreases with the frequency, getting the maximum at 20 Hz. The mathematic model of the actuator was also built up. Based on the simulation results, a prototype of electromagnetic linear actuator with appropriate parameters was developed. And the electromagnetic force test of the actuator was done. By comparison of the finite element simulation results and the experimental data, it shows the corresponding results are consistent, indicating that the design and analysis of the electromagnetic actuator is correct.

Lai Fei, Huang Chaoqun

Research on Nonlinear Characteristics of Hydro-Pneumatic Spring and Impact to Ride Performance of Vehicles

The relationship of nonlinear stiffness and natural frequency of vehicle body is analyzed. Nonlinear stiffness of hydro-pneumatic spring is modeled and simulated using the software Matlab/Simulink. The impact of two main parameters to the nonlinear stiffness is analyzed. The nonlinear stiffness is added into 2-DOFs vibration model and the results of simulation are competed with linear condition. The characteristics of two levels stiffness is verified by the bench test. Finally, some conclusions as to nonlinear characteristics and impact to ride performance are given.

Junwei Zhang, Sizhong Chen, Zhicheng Wu, Lin Yang, Bin Zhang

Simulation Research on Car Suspension Durability Enhancement Test Based on Virtual Proving Ground

In this paper, a simulation model of flexible virtual proving ground (VPG) for a car was created in view of the shortcomings of long test cycle and high cost of traditional enhancement test for suspension durability at car development stage, with a variety of durability enhanced roads in the Nong’an Proving Ground as inputs. It solved a string of key technological problems regarding VPG applications. In addition, the time-history dynamic stress response of a car suspension system was analyzed, compared with the real vehicle durability test results obtained under the same conditions. The results of the simulation test and the real test are basically identical in terms of the trend of time and frequency domains. Furthermore, it demonstrates the effectiveness of the simulated suspension system’s dynamic stress response for the flexible VPG technology, and realized the effective prediction for the suspension system durability in the development process.

Zhenglin Cao, Jun Li, Konghui Guo

Simulation Research on Strong Fluid–Solid Interaction of Hydraulic Engine Mount

This paper sets the hydraulic engine mount (HEM) of a car as its research object and established the strong fluid–solid interaction finite element model for its property analysis by adopting the INTESIM strong fluid–solid finite element method. A stimulation analysis of the model’s static and translation dynamic stiffness characteristics was conducted,compared with the experimental result and the effectiveness of the simulation research findings was verified. The research demonstrates that the translation dynamic characteristics of the HEM can be effectively simulated by the INTESIM strong fluid–solid finite element method; on the basis of which, a preliminary discussion on its torsion dynamic stiffness characteristics was carried out also.

Zhenglin Cao, Jun Li, Konghui Guo, Qun Zhang

A Study on Battery Model Verification Using Battery HILS

The development of technology for environmentally friendly cars such as plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EVs) has increasingly progressed according to the conversion of vehicle development paradigms to energy issues, environmental regulations, the government’s “New Deal” policies, and so on. As a result, the importance of the battery system that is the main power source for environmentally friendly cars has grown. The most effective way of the development of PHEVs and EVs is using battery hardware-in-the-loop simulation (HILS) to significantly reduce development costs and time in vehicle-level environments for the development and evaluation of battery systems, including a battery management system (BMS). Therefore, in the present study, a battery HILS was developed and tested. It was noted through the test that the developed battery HILS could be used as a method to assess the accuracy of battery modeling in real time by applying it to developed battery system models using the electrochemical impedance spectroscopy (EIS) method.

Hyun-Sik Song, Tae-Hoon Kim, Jin-Beom Jeong, Byoung-Hoon Kim, Dong-Hyun Shin, Baek-Haeng Lee, Hoon Heo

Extended Flexible Environment and Vehicle Simulation for an Automated Validation

In FISITA 2010 IPEK (Institute of Product Engineering) introduced the vehicle-in-the-loop platform based on its X-in-the-loop approach (F2010-C-177) (Albers and Düser, Implementation of a vehicle-in-the-loop development and validation platform, FISITA world automotive congress, Budapest, 2010). It offers a methodology for multi domain product development and validation as well focuses on its key hypothesis that validation is the main task in every step of product development process. An open hardware and software platform allows integration of different real components and simulation models as well as the usage of established tools and methods for measurement and validation. The platform is based on a common hardware-in-the-loop System using extended I/O-communication to the vehicle and the test bench. The application is done in C code and Matlab/Simulink so an easy exchange of modular simulation models and test cases is feasible. The architecture of model-, component- and test case implementation simplifies the scalability as well as the modularization. IPEK uses this platform amongst others for its improved fully automated validation environment which allows the optimization of operating time for determination of shifting quality on the chassis dynamometer. The task is to perform several hundred gearshifts under particular reproducible conditions automatically such as engine speed or even battery state of charge, which normally a real driver had to perform on a real test track. Compared to road tests on the rig it is possible to reach time benefits of over 80 % by using a special driver model for acceleration (using gas pedal), deceleration (using dynamometer) and gear shifting (using tip signal at steering wheel). Since the vehicle behaviour on the road is constrained to different environmental conditions it is necessary to reproduce these conditions on the test bench accurately. Different resistances affect the vehicles responses such as shifting strategy, acceleration characteristics or fuel consumption which results in altering test results. State of the art for simulating environmental conditions and vehicle characteristics on the chassis dynamometer is the Road-Load-Simulation (RLS) which uses measured vehicle coast downs to map the static resistances of a real car on a real track onto the test bench. These coast downs have to be redone every single time components of the car or the environment changes. In addition, changing resistances during test like air drag due to headwind and rolling drag due to tire temperature or abrasion can’t be simulated based on that static coast down. This paper shows an approach for simulating all kind of resistances that can appear and vary during the test such as air drag (wind), road gradient, road friction, curve resistance etc. in real-time. It can be used to drive test cases like the determination of characteristic shifting map in a more realistic way to perform better validated results. Central point is a configurable vehicle and environment model which has to be parameterized with data from the real car and track and then calculates the necessary dynamometer responses. Applied with a four roller dynamometer (two or even four driven axles) it offers the possibility to perform complex all-wheel manoeuvres e.g. such as μ-split or cornering with independent wheel behaviour and slip. Besides the advantages of this approach, an analysis of different influencing factors is shown in this paper.

Albert Albers, Rolf Hettel, Matthias Behrendt, Tobias Düser, Alexander Schwarz

Application of Energy Distribution Analysis During the Vehicle Development

Faced with rising vehicle energy saving and environmental protection requirements, if you rely solely on a field of energy saving and consumption reducing, it is hard to get the required amount of goals to improve. And how will the vehicle fuel consumption reduction target value that you want the correct segmentation into fuel consumption reduction target values in various fields, will be the key to compliance. This research goal is to establish a decomposition model of vehicle fuel economy of consumption, by decomposition on vehicle fuel consumption target value, make of vehicle fuel consumption reduction target value easier to reach. Product development, will CAE simulation technology combined with the variety of real train test data, is to reduce the cost of development, an effective method to shorten the development cycle. Research methods in this chapter is through CAE simulation analysis of establishing vehicle fuel economy of consumption model, is allocated for vehicle fuel consumption management, vehicle fuel economy of consumption is divided into the following energy consumption model: engine loses energy consumption model, brake system energy consumption model, train energy consumption model, model of energy consumption of air resistance, rolling resistance model of energy consumption. And verified using experimental data on the energy decomposition model, continually modified and improved the energy decomposition model. Establishment of decomposition technique system of passenger automobile fuel economy, correctly grasp the body and chassis drive, engine and vehicle technology in reducing fuel consumption, energy distribution practices. In the development of a model of the company, through the use of energy consumption distribution model of the study on rational allocation of vehicle fuel economy target values for confirmed their fuel economy target of the project model, allowing the automobile to standard three phase fuel consumption limit values easier. Due to the lack of product development experience and development data, may result in the model decomposition energy consumption of different automobiles in different degrees of error model, even its accuracy may also apply only to the model developed by the model. But with the development experience and data accumulated, the study on the establishment of decomposition models will continue to improve vehicle fuel economy, shorten the development cycle, reduce development costs of this research will play a key role. Vehicle fuel economy reflect the model of comprehensive performance indicators. Must be involved in all areas, such as: transmission of body and chassis, engine and vehicle technology in terms of performance and match the overall optimization. This innovative approach of the study is established through the CAE simulation model for vehicle fuel consumption, and using reasonable collection of test data and optimized using experimental data for model validation, and constantly improve the vehicle’s energy consumption model with the. By establishing a decomposition model of vehicle fuel economy, vehicle involves different areas of the development of a rational energy consumption objectives, can greatly shorten the development cycle and reduce development costs. Therefore, in the future of the company’s new product development, the study on the establishment of the vehicle fuel economy decomposition model will become an indispensable development tool.

Yongsheng Long, Jianpeng Shi, Li Xin, Xueen Zhang, Jun Wang, Shaoju Qu

Simulation and Correlation of Commercial Axle Banjo Housing Fracture Under Braking Fatigue Test

Three samples of commercial automotive axles were fractured prematurely in lab under braking fatigue test. Crack has initiated at similar location in all three samples. Investigation of fracture was done using Finite Element (FE) approach. Finite element model was validated with strain values which were obtained prior to fatigue test. Correlated model was further utilized for fatigue life prediction. Strain-life approach was used for fatigue life prediction. Fatigue material properties were approximated using Four Point approximation method. Fatigue life estimation was done and compared with braking fatigue test data. Design modifications were suggested to improve the fatigue life. FE analysis and fatigue life was re-evaluated virtually on modified design to endorse the conclusion.

Ajay Guddeti, Abhijit Nilangekar

Development of a Vehicle Simulator Based on a Real Car for Research and Education Purposes

The chapter presents a hardware-in-the-loop simulation environment, which is built in such a way that the simulator tends to the real vehicle functions as much as possible. The simulation system contains several components such as an Human Machine Interface (HMI), a high-accuracy validated simulation software operated on a PC and a visual system with real-time graphics. The simulator is equally suitable for educational and research purposes. All the vehicle engineer students use the simulator system during their curriculum, enabling the thorough understanding of modern vehicle functions, thus improving the competence of future generations of engineers. Moreover, the simulator system projects ahead the opportunity of new vehicle research that induces considerable additional scientific results.

Zsolt Szalay, Péter Gáspár, Zoltán Kánya, Dávid Nagy

Early Verification of Complex Distributed Systems Using Model Driven Development and Virtual Engineering

Research and

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or Engineering Questions

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Objectives

System-level modeling accelerates the development of distributed mechatronic systems by automating tasks and maintaining the integrity of validated executable specifications and test benches. This paper presents a systematic distributed embedded system development methodology that provides abstraction of hardware and software concerns, facilitates communication via highly accessible models, and promotes reliable early development of both hardware and software. The focus is on the development of complex mechatronic systems with specific emphasis placed on early development and subsequent reuse of hardware-dependent software components and on the concurrent and independent development of embedded electronic hardware, software, and physical plants.

Methodology

Complex interactions between physical plants and distributed embedded computing components make developing mechatronic systems very difficult—even when everything is fully specified. New technology options add further complications and require diversified skills from system developers. Designers must deal with embedded software, electronic control units (ECUs), electro-mechanical subsystems (mechatronics), and the networks through which they communicate. In order to manage change and accelerate development, collaboration within disparate groups of people is essential; various cross-sections of engineering disciplines must be allowed to work independently from each other without incurring huge integration costs in subsequent development phases. Model Driven Development (MDD) has been a term used in our industry for some time, but it has had a hard time achieving widespread adoption and respect as the most effective way to drive a design process. It accelerates the creation, verification, and validation of embedded software using models as the primary engineering deliverable.

Results

Domain experts use MDD techniques to complete application-specific tasks early, using highly accurate mechatronic models. As projects progress through architectural design, functional partitioning, and detailed component design, the coherence of a system’s model is maintained via communication abstractions, reuse of standard system-level architectures, and automatic C/C++ code generation. These capabilities decouple the decision points and ease regression testing to accelerate development as early confirmed strategies are successively verified when networks, actuators and sensors, real-time operating systems, embedded processors, and other sub-systems change. Models are captured using standard modeling languages such as xtUML and can be transformed, automatically, into production-ready C/C++ embedded software. Virtual Engineering augments MDD to provide a realistic modeling alternative—using modeling standards such as VHDL-AMS—to the physical electronics, mechanical devices, and other hardware that make up the typical environment that surrounds software under development.

Limitations of this Study

The technology boundaries inherent in such systems pose two main problems for design teams: compatibility between tools and communication between specialists. Conventional simulation tools cannot adequately deal with diverse modeling requirements; also, technology specialists speak a unique design language that is tailored to his/her specialty. As systems become more complex, contractors who once specialized in narrow technical areas are being forced to act as systems integrators and in turn, are contracting subsystems to a global network of subcontractors. It adds up to significant potential for misunderstandings, errors, and omissions due to communication challenges across language and cultural boundaries.

What does the paper offer that is new in the field in comparison to other works of the author

MDD provides an approach to the challenge of technology change by separating the application portions of a system from underlying platform technology. This technology promotes early, independent, and concurrent development by empowering designers to focus on application models without regard to platform-specific details. This is the difference between MDD and model-based development. MDD completely preserves early application modeling artefacts; the latter repeats modeling efforts for each platform variant.

Conclusions

This paper describes the capabilities of a virtual system integration environment that supports conceptual system development used early in the design cycle, as well as complete distributed system development on final embedded computing hardware. It describes how MDD improves productivity in the design cycle, automatically generating parts of a design, thus improving quality by bringing in repeatability and standards compliance. It shows how design team members working on complex projects in disparate locations can effectively collaborate using a common modeling and analysis environment, allowing a common modeling and analysis environment to act as a communications vehicle for the entire team.

Lance Brooks, Jun Wu, Darrell Teegarden

Research in the Impact of Curtain Airbag Deployment on Interior

In this paper, Hypermesh and LS-DYNA were used for simulation modeling of complex curtain airbag based on particle method. A static detonation slider impact test was designed to verify the validity of the simulation model. The paper focused on the impact of curtain airbag deployment on the surrounding interior. The results showed that: curtain airbag simulation model based on particle method was reasonable and valid; during the curtain airbag deployment process, trim panels on the edge of B-pillar and C-pillar received more concentrated stress and strain; the opposite direction aircraft had a major impact on the curtain airbag, and deformation of the trim panels on edge of B-pillar and C-pillar was bigger without guide frame. The research results provide effective ways and reference for the design of curtain airbag and interior system.

Shuyuan Zhou, Liangming Xiang, Jie Lou, Wenwei Zhang, Min Xu

Multi-Domain Modeling and Simulation of Automotive Air Conditioning System Based On Modelica

The automotive air conditioning (AC) systems are complex systems where two-phase flow, pneumatic, mechanical and electrical components are coupled. Such systems coupled with various physical domains have great influence on comfort and dynamic performance of the vehicle, such as cooling performance, driveability, fuel economy, etc. This paper presents a detailed model of AC system, including the condenser, evaporator, compressor, expansion device, etc. The simulation was carried out to study the performance of the AC systems, and the effect on the vehicle performance was studied.

Jing Li, Yunqing Zhang, Wei Chen

Predictive Energy Management Strategies in Virtual Driving Tests: Early Evaluation of Networked Controller Functions in Realistic Use Cases

Research and/or Engineering Questions/Objective

The evaluation of vehicle characteristics at an early phase of functional development is a key task in the definition of a viable system and function architecture. Today this is complicated by the fact that full vehicle characteristics, in particular those of modern hybrid and electric vehicles, are dependent on a broad range of electrical, mechanical, thermal and control-related partial aspects. In addition to the current driving status and information on the environment, modern energy management systems (e.g. control systems, range, charging and thermal management) also require predictive information on the driving route to be expected. This includes, for example, uphill road grades, curve radii, speed limits, number of lanes, urban and residential areas, intersections and traffic lights. All together, the intelligent fusion of this information provides for increased safety and energy efficiency.

Methodology

These additional functions however result in additional complexity in the development process, which must be controlled. Nevertheless many questions already arise in a very early phase of development, in particular in the interaction with the actual utilization profile, such as route, driver and environment characteristics in the various target regions of the future vehicle. This article shows new ways and methods of how the functions and total vehicle characteristics can be evaluated in virtual driving tests in the early phase of development. The method provides a major support for the development and evaluation of energy management systems in the complete vehicle environment with corresponding system interactions: The evaluation of energy states, losses and fuel consumptions in realistic utilization profiles, such as route, driver and environment characteristics in the various target regions of the future vehicle.

Results

In addition to the evaluation of the individual target functions in a broad range of different scenarios, the correct designs of the individual system components in the complete vehicle can also be verified. The performance and robustness of the operating strategy, as well as the corresponding fuel consumption or CO

2

emission values in the range of worldwide conditions of use can also be predicted with the different choice of route and driver types and the amount of traffic typical for the region.

Limitations of this study

Furthermore, positive fuel consumption effects are identified in the virtual driving test which cannot be recognized due to the insufficient repetitive accuracy in actual traffic. During this, the method can be consistently and uniformly used in the x-in-the-loop development process. As soon as hardware components like the engine, drive train or battery are available, these actual components can already be tested in the virtual driving test in combination with the virtual vehicle in accordance with the principles described.

Conclusion

As a result, the system and functional architecture can already be comprehensively evaluated in a very early development phase and the degree of integration maturity in the later, actual integration levels can be raised to a considerably higher standard, minimizing time-consuming, expensive development loops.

Andreas Kunz, Bernhard Schick, Steffen Lange

Evaluation of Video-Based Driver Assistance Systems with Sensor Data Fusion by Using Virtual Test Driving

Research and/or Engineering Questions/Objective

The vehicle of the future will support its driver by advising him regarding potential hazards. Essential prerequisite therefore is the sensor based perception of the traffic situation. For the recognition of traffic related objects, camera based sensors, deepness cameras, vehicle sensors as well as radar and lidar sensors are used. For the future development of ADAS the fusion of multiple sensor data to a consistent environmental picture will play a key role. The evaluation approach of real world driving tests will no longer be sufficient due to the complexity of the system interactions. New simulation methods are needed to evaluate ADAS by using virtual test driving with realistic vehicle behavior and complex traffic environment.

Methodology

Therefore it is important to integrate camera based components in a “closed loop”-simulation platform to be able to test sensor data fusion technologies under realistic conditions. To test new driver assistance systems in a simulation environment today animation data is filmed, subsequently this data is used to test an image processing algorithm or a fusion algorithm. But this method cannot be applied if wide-angle cameras such as cameras with fisheye lenses will be used. Within a research frame work for autonomous driving functions a new simulation technology was developed to integrate virtual cameras beside the well know environment sensor in the vehicle dynamic simulation CarMaker. For this purpose the real-time animation was extended with a sophisticated virtual camera model so called “VideoDataStream” to generate simultaneous video data (also PMD for 3D images). The camera positions as well as the camera properties could be applied individually. Additionally it is possible to freely define the type of the camera lens (e.g. fisheye) with lens settings like opening angle and the typical lens failures (e.g. distortion and vignetting). With this new technology it is possible that e.g. camera and radar data can be provided time and place synchronal for the fusion algorithm which should be tested!

Results

The video data could be used for evaluating image processing and sensor data fusion in Model-/Software-/Hardware-in-the-Loop applications within virtual test driving conditions. Here the created method and examples of image based perception of the vehicle environment as well as sensor data fusion algorithms shall be presented. Among others this covers first of all the recognition of traffic lanes, traffic signs and other traffic partners as well as the fusion of the single information up to a comprehensive environment picture. A further field of application will be the conjunction with navigation systems and digital maps, by which the virtual vehicle supports the navigation system with related GPS position and gets back the “MPP—Most Probable Path” with the “electronic horizon”, which is a type of predictive sensor, with all related preview information in front of the vehicle which are defined in the ADASIS protocol.

Conclusion

By using the introduced method the capability and efficiency of function development and testing in the area of Advanced Driver Assistant Systems will significantly be improved. Due to a powerful simulation environment a broad range of validation tests can be shifted into simulation because also complex test scenarios can be replicated and the tests are reproducible. The simulation data can be provided time and place synchronal, which is absolutely important, e.g. for a fusion algorithm which should be tested.

Bernhard Schick, Steffen Schmidt

Vehicle Warm-Up Analysis with Experimental and Co-Simulation Methods

A high accuracy of full-vehicle thermal models are required to predict the vehicle heat-up behaviour at every conceivable combination of driving cycle and ambient air temperature down to −20 °C. Within this work a methodology for modelling the thermal behaviour of an IC-engine is presented. The focus lies on the heat-path beginning with the combustion process followed by heat conduction through the combustion chamber walls and convective heat transfer between engine structure and coolant. The thermal engine model is coupled with other models (HVAC-system, powertrain, etc.) by an independent co-simulation platform in order to describe the virtual vehicle as a whole. Finally, the model validation is performed with two different driving cycles at two different start temperatures. Using the described full-vehicle model the potential of a heat storage system is discussed for several heat-up strategies.

Daniel Ghebru, Christian Donn, Wolfgang Zulehner, Heiko Kubach, Uwe Wagner, Ulrich Spicher, Wolfgang Puntigam, Klaus Strasser

Modelling and Simulation of AMT Truck Clutch Actuating Mechanism

The phenomenon of excessive separation and combination for clutch is caused by characteristics of pneumatic actuator itself when a heavy-duty AMT truck is starting and shifting. In order to solve this control problem, it was the first time to establish mathematic model of a heavy-duty truck clutch pneumatic actuator based on clutch pneumatic actuators working principle and gas dynamics basic theory, set the clutch cylinder piston target location in separation and combination, and make the simulation research in this paper. The validity of clutch pneumatic actuators model was verified using bench test. The basis for the preliminary work has laid for heavy trucks AMT control systems application program and the control strategies development.

Yanying Guo, Xintian Lu, Tao Yan, Zhonghui Sun

Vibration Fatigue Analysis of Adaptive Front Lighting System

This chapter discusses the computer simulation methodology to predict the crack initiation fatigue life cycle of automotive Adaptive Front Lighting System (AFLS) under vibration. The AFLS improves visibility by changing the beam pattern of an automotive headlamp in accordance with various driving conditions. As the mechanical linkages consisting of projection module of the AFLS are slender and light-weight for functionality, packaging and fuel economy, the AFLS might exhibit nonlinear dynamic behavior by external vibration that the traditional Finite Element (FE) based frequency response analysis fails to simulate. By including kinematic behavior such as the leveling and the swiveling of the projection module and the nonlinear stiffness of pivot sockets into analysis model, the combination of Finite Element Analysis (FEA) and flexible multi-body dynamics (MBD) analysis can show more realistic vibration characteristics and predict the reliable fatigue life cycle of the AFLS.

Yeon Gyoo Lee, Seungryul Choi, Tae Ryong Jeon

Application of Two-Chamber Muffler to Reduce Car Noise in Engine Intake System

There is obvious noise while a vehicle accelerating, under the engine speed at 2410 rpm and 3,650 rpm. Based on tests it is found that noise is induced by engine intake system. In order to reduce the noise level a Helmholtz resonance muffler is introduced, which is widely used in engine intake system. Generally, several resonance mufflers are needed to reduce the same number of noise peaks. This way is not good for cost control and space arrangement. In this paper, the theory of Helmholtz resonance muffler with two chambers is applied and transmission loss analysis is done to determine the chambers’ sizes to reduce the noise level effectively. A sample of intake system is made based on the simulation results, and validation tests are conducted to confirm the improvement in car noise reduction.

Zhihong Tang, Zhenying Zhu, Yongxin Men, Fuquan Zhao

Ergonomic Simulation and Optimization During the Body Assembly

The ergonomic simulation is significantly important to reduce the cost and shorten the product development cycle in the vehicle development. In this paper, the technological design and simulation validation are performed with regard to assembly process of subframe subsystem and body structure on a particular vehicle. During the simulation, the problems are found as follows: (1) There is interference between dolly front pillar and spreader bottom when the subframe subsystem is transported; (2) The blind area happens to an operator at the static operating posture. The assembly operation needs to be accomplished by means of human body. Furthermore, the operator’s neck and arms are subject to fatigue. When cyclic load is applied, fatigue usually appears on the operator’s body. The analysis results indicate that interference can be avoided by optimizing the spreader structure and relative position or adjusting the dolly front pillar by nearby operator when the dolly goes through the spreader. By modifying the location of installation points, an easy assembly can be completely achieved, and fatigue can be substantially eliminated as well.

Yanjun Gao, Xianbo Wei, Beifang Ma, Yang Yu, Xingmin Wei, Fuquan Zhao

Test and Analysis of the Mechanical Properties for Laser-Welding Seams and Spot-Welding Joints

Laser welding seams and Spot-welding Joints are wide used in auto body design. It is important for the body design engineers and CAE engineers to understand the mechanical behaviors of spot-weld joints and laser-welding seams. The objective of this paper is to introduce a test method to study the mechanical properties for laser-welding seams and spot-welding Joints by test and simulation.

Liling Zhang, Xuefeng Chen, Qing Jiang, Xu Wang

Aerodynamic Design and Numerical Simulation Analysis of a Passenger Car’s Defrosting Duct

Many cars are equipped with the same Heating, Ventilation and Air Conditioning (HVAC) system with different outlet flow rates, shapes, sizes and positions etc. according to modern automobile modular and platform design strategies. Consequently, the aerodynamic design of airflow duct has become an important issue of the automobile HVAC system. In this research, the HVAC defrosting airflow canal of a passenger car was designed using Computational Fluid Dynamics (CFD) method. The HVAC defrosting outlets’ sizes and positions were considered as design variables. The mass flow rate distribution and the cabin flow structure were considered as design targets. The steady Reynolds Averaged Navier–Stokes (RANS) method was adopted because it is an efficient way to help select possible good designs in the early stage of new product development without time consuming and huge computational cost of the unsteady methods. Various duct design configurations were evaluated by analyzing the defrosting mass flow distribution of each flow outlet and by visualizing the flow structure near the windshield and the front left side window. The CFD results showed that the total area of the outlets near the rain wipers was a decisive parameter for mass flow distribution in this duct design. The defrosting flow structure near side windows were difficult to be improved only by enlarging the area of the outlet. The effective flow structure was realized by choosing proper angles of the vanes skirt of the outlets to defrost the windshield region. The overall performance of HVAC system, such as defrosting time and cabin temperature distribution, could not only be predicted based on the results of the steady RANS method. It was shown that the important parameters including the mass flow distribution of each outlets and the flow structure near the windshield and side windows could be quickly evaluated from the steady state CFD simulation results in the early design stage.

Bo Yang, Li-na Huang, Fengtao Ren

An Operating System for the Optimization of Technical Systems Using the Example of Transmission Calibration

Technical systems must be continuously improved so that they can remain competitive in the market. The duration and the costs of the development process are important factors of success for a company. Therefore practical methods and processes have to be provided to create an efficient optimization process. Within this paper an operation system for a time efficient, test based optimization of technical systems will be presented. Therefore methods from simulations and tests are being combined. Based on the X-in-the-Loop approach (XiL) it is possible to examine the Unit under Test (UuT) on an overall vehicle level in interaction with the environment and the driver. This way, even complex interactions between the systems can be emulated concerning examination- and optimization- goals. This also allows validating and optimizing modern, strongly interconnected drive systems. Especially hybrid powertrains present major challenges to the test because the additional state variables like SOC as well as engine and operating temperatures have to be considered and adjusted if necessary. This operation system provides the methods to reduce the time of conventional test runs as well as methods for model based optimization. Conventional approaches use non-physical models like polynomial-approaches or artificial neural networks for the optimization. In contrast, the presented approach allows the use of models partly consisting of physical parts. Thereby, the model quality and the expenditure of time for testing can be reduced significantly. Even conventional test runs with various measuring points, like monitoring of shifting quality, can be shortened significantly by this operation system. In the example of the gear shifting evaluation of a dual clutch transmission the expenditure of time can be reduced by 80 %. Therefore, several measuring points are being defined throughout the different shifting modes (different accelerator pedal positions, rpms, gears, driving situations and driving maneuvers) and put into an ideal order. This means, the system calculates the order for a minimum time of conditioning between the measuring points (reaching the desired initial condition).

Albert Albers, Alexander Schwarz, Matthias Behrendt, Rolf Hettel

Model Structure, Realization and Learning Process For a Driver Model Being Capable to Improve Performance with Learning by Itself

Vehicle electrification has been extended rapidly in a recent few years and development work for those has been added to conventional vehicles. Model based development (MBD) methodologies have been adopted widely. A dynamic driver model is required for controller design considering driver’s behaviour and for verification with SiLS and HiLs in the MBD process. Some higher response and multi-variable control systems can be constructed with electronic devices. However, human control is not so quicker and not capable to handle multi states. There have been a lot of published papers regarding to driver models. Structure of the driver model with constrains of human property and learning process seems to be under study. Authors have investigated driver models for target speed tracking driving in emission test cycles in which the target is clearly defined. Taking account of constrains with driver’s response and information processing capability, a driver model structure, feed forward operation based on prediction and additional error feedback correction, is introduced. A learning algorithm to obtain inverse vehicle property for the feed forward control is proposed. Knowledge which enables to select features to be learned and condition for stable learning process are discussed. Numerical simulation illustrates driving behaviour from a beginner to an expert with the driver model. Further, it is shown that speed tracing driving performance with a novice driver model could be improved when vehicle property is changed, e.g. an IC engine is replaced by an electric motor. It is supposed that the proposed method is also applicable to development process for a lower order and rower sample rate controller with adaptation functionality.

Kazuhide Togai, Hisashi Tamaki

Virtual Design , Testing and Validation

Frontmatter

The Suspension Optimization of FSAE Racing Car Based on Virtual Prototyping Technology

Research and/or Engineering Questions/Objective: One important design goal of racing car suspension is to keep the tire perpendicular to the ground which needs an accurate kinematic design of suspension. This paper details the simulation method of FSAE racing car based on MSC.ADAMS and VI-Motorsport, then the optimization of suspension kinematic characteristic could be conducted. Meanwhile, the paper will show the effect of suspension kinematic characteristic on lap time. Then the problem that the developing period of FSAE racing car is not long enough to conduct sample prototype test can be solved by the performance prediction and optimization by virtual prototyping technology.

Methodology

: The virtual prototyping model of BIT FSAE racing car and a certain race track were built by multi-body dynamics simulation software MSC.ADAMS and professional racing car simulation software VI-Motorsport. During the modelling process, the non-linear mechanical characteristic of tires was taken into consideration by the tire data provided by FSAE TTC, as well as the aerodynamic characteristics. The correctness of the model was verified by the “g–g” diagram collected by data logger in competition, then the further analysis and optimization could be conducted based on these. The comparison of lap time between the original race car and the race car after optimization was also conducted by simulation.

Results

: The comparison of lap time simulation results shows that the grip of tire during turn is increased after optimization of suspension, and the lap time is reduced.

Limitations of this study

: The simulation is based on multi-body dynamics simulation which assumes the chassis and suspension as rigid body. It brings some errors because the compliance characteristic of chassis and suspension is ignored. What does the paper offer that is new in the field in comparison to other works of the author: In previous technical papers in FSAE racing car field, there is no precise comparison between simulation results and actual data. But in this paper, the correctness of the model was verified by the comparison between simulation results and actual data collected in competition. And in this paper, the “g–g” diagram of FSAE racing car was first presented and discussed which is vital important of racing car performance.

Conclusion

: The simulation of FSAE racing car lap time based on MSC.ADAMS and VI-Motorsport has a high accuracy which could provide a possibility of performance prediction. It can shorten the developing period of FSAE racing car and improve the performance of FSAE racing car. Furthermore, the designers can adjust the kinematic design of suspension to meet different requirements in different race tracks by the proposed method.

Jun Ni, Sizhong Chen, Zhicheng Wu

The Study of the Impact of Aluminum Formability Parameters on its Stamping Formability

To find parameters to estimate stamping formability of aluminum alloy sheet in autobody, simulate the cylinder components stamping process by LS-DYNA software based on dynamic explicit method; Study the impact of the material parameters (Yield stress RPS, hardening exponent n and anisotropy parameter r) and the process parameters (the blank-holding force and friction coefficient) on the stamping formability of the aluminum alloy sheet; Analyze the corresponding relationship between the research targets (material and process parameters) and the drawing properties through the Regression Analysis. The results indicate that the n values of the material parameters and all of the process parameters in this paper are remarkably correlated with the drawing properties of aluminum alloy, while the r values of the material parameters have little correlation with it.

Jian Zhang, Mingtu Ma, Hongzhou Lu

Calculation of Shrinkage Rate for Injection Molding Based on Moldflow

During the process of injection molding, shrinkage rate varies on plastic type, product structure, processing parameter, flow gate size and location. Traditional shrinkage rate estimated from mold designer’s experience makes it quite difficult to meet the accuracy requirements on products, especially in terms of big size items like automotive interior and exterior. This paper introduces the accurate calculation of shrinkage rate for injection molding by computer simulation via MOLDFLOW software, and researches the factors influencing shrinkage rate, which holds guiding significance on improving the pass rate of big size injection molded items.

Fangcheng Xiao, Lei Chen, Xiao Wang

A Study of Contact Condition in Vehicle Transmission Virtual Assembly System

Facing violent market competition, how to push new product into market with the fastest speed is the key to the survival of the enterprises. Virtual Assembly is the trend of the manufacturing development today. Data glove, as a human computer interactive tool in Virtual Reality, is an important device in virtual assembly. In this paper, the principle and functions of the data glove are studied. Data glove and virtual part’s contact condition detect is done. An interaction and control module of data glove is designed, with which man can assemble the transmission in virtual environment conveniently.

Yan Chen, Shouwen Yao, Fei Liu

The Multi-Properties Modeling Technologies of Virtual Assembly for Vehicle Transmission Based on the Design

According to the design requirements of transmission system, the multi-properties model of virtual assembly was researched on the basis of physical properties. The multi-properties models of transmission system were established by multi-properties modeling techniques. Visualization simulation of virtual assembly process of transmission is realized by the accurate collision detection, structure analysis, large scene simulation platform and other technologies and methods. Simulation of virtual assembly for vehicle transmission is implemented combined with virtual visual scene. Related performance analysis of transmission based on virtual assembly was done in this paper. These analyses will play an important role on the structural design of transmission.

Fei Liu, Qingdong Yan, Shouwen Yao, Xin Zheng

New Technologies in Driving Dynamics Performance Simulation

Today’s vehicle dynamics engineers are facing many different challenges at the same time, such as achieving full vehicle response target requirements for ride and handling, simulating accurate road loads prediction, developing and integrating chassis subsystems (such as steering, brake, damper) and even the more complex active safety systems, keeping a good balancing compromised solution with other vehicle performances such as road noise, passive safety and NVH. In order to answer to such complex panorama, vehicle dynamics engineers are using CAE for the development of a vehicle with usage of 1D modelling and 3D MBS and FEA. The concurrent use of all these technologies represents a standard in the automotive industry, depending on the frequency range and on the vehicle development stage. However, the current simulation process is not efficient because there is very limited integration between the different approaches. In addition local geometrical and material nonlinearities are not accurately modelled in classical MBS software. This paper introduces an integrated methodology for vehicle dynamics simulation with particular application to MBS nonlinear FEA environment. The integration of MBS capabilities in one single nonlinear FEA environment enables an accurate modelling of nonlinearity in vehicles. The advantages of using the “Motion in FEA” simulation capabilities are demonstrated with relevant vehicle dynamics examples. The “Motion in FEA” approach is very accurate since it can describe all the non-linear effects present in the vehicle. As they are not limited to low frequencies or connection modes, results are more accurate. With respect to the engineering process efficiency the “Motion in FEA” model also allows eliminating unnecessary iterations between local separate mechanical models, improving productivity during the complete vehicle development process.

Cibrario Valerio, Cugnon Frederic

Transmission System Design and Manufacture in FSC Racing Vehicle

This paper is mainly devoted to transmission system design and manufacture in FSC vehicle. Based on the rules of FSC and design goals on the vehicle, the principle for FSC transmission system design is proposed. The optimal transmission ratio is gained from both the classic formula of vehicle dynamic and analysis in Matlab. Chain transmission system and the idea of its integrated design are adopted. To optimize the system, different scenarios are considered including various constraints and configuration through modelling and simulating in Solidworks. With a balance among lightweight, stiffness and strength, we build up a transmission system fitting to FSC vehicle, and the results of long-term test show that it is reasonable and efficient. Finally, some practical problems and their solutions are discussed and references for the future relative research are provided.

Zhenpo Wang, Changfu Zou, Lei Yue, Lei Zhang

Parallel Design Optimization of Articulated Heavy Vehicles with Active Safety Systems

This paper presents a parallel design optimization method for multi-trailer articulated heavy vehicles (MTAHVs) with active safety systems (ASSs). It is a challenge to deal with the trade-off between high-speed stability and low-speed maneuverability. Evolutionary algorithms have been used for the design optimization of MTAHVs, but the computation efficiency is low. To address the problem, a parallel computing technique with a master–slave system is proposed. Active trailer steering, differential braking and anti-roll sub-systems are combined in an integrated ASS. Considering the interactions of Driver-Vehicle-ASS, the method simultaneously searches optimal active and passive variables of the ASS controllers, the driver model, and the trailers using a master–slave computing system. Simulation results indicate that the proposed method provides an effective approach to the design synthesis of MTAHVs with ASSs.

Manjurul Md. Islam, Steve Mikaric, Yuping He, Thomas Hu

The Application of Dual Limit Analysis Method in Physical Performance Characteristics Defining and Structural Designing

Dual limit analysis method that can be widely used in stress analysis and judgment for the mechanical components, including the movement mechanics and finite element static mechanical analysis; and can be used in the social sciences, economics decision-making for the event, events, game, life choices, the program decision-making. To the dual limit analysis, we can use the coordinate system to express their inherent relationship. Because the event or project components, does not exist in the negative, so it can not be expressed with the traditional Cartesian coordinate system, we need to create a cross positive coordinate system to express. So, dual limit analysis method in the event judgment is a fuzzy analysis method to judge, but with the constantly adding the more parameters, this ambiguity will turn to clarity, add some precise value allows the results get closer to the clear. Dual limit analysis method has a great impact especially on fuzzy mathematics.

Chi Luo

Predicting Battery Pack Thermal and Electrical Performance in a Vehicle Using Realistic Drive Cycle Power Profiles

The heat generated during battery charge and discharge cycles is a major design issue, particularly since the performance of a battery depends on its operating temperature. As a consequence, robust thermal management systems are required to provide the operating conditions needed to assure the performance and reliability of the battery packs. Subsequently, computer-aided engineering tools that model the thermal behaviour of a battery are needed to assist with the design and integration of battery packs into vehicles. To meet this need, we have developed a coupled thermal-electric model for battery systems. This paper describes the development and use a computational model to predict battery pack thermal and electrical performance in a vehicle undergoing a realistic drive cycle.

Allen Curran, Scott Peck

Virtual Test Drive in the Application Process of ESP®-Systems to Ensure Performance and Robustness

Vehicle dynamics simulation is a well established tool in the function development and in software testing of ESP®—the Electronic Stability Program. Due to an increase of vehicle variants, additional ESP® features, legal requirements and the pressure to increase the overall efficiency in the development process vehicle dynamics simulation is becoming more and more a part of the ESP® application process. For this purpose increased requirements of the simulation models, the set-up process of the simulation environment and finally the test cases have to be met. This paper describes the ESP® specific simulation methods, the environment and the related process between OEM and supplier to set-up and run the simulation platform commonly. Examples are presented which are applied in two phases in the application process. One is the frontloading process to set-up an initial mature software (SW) supported with simulation. The other one is the handling of projects with a large amount of vehicle variants. In both cases simulation is used to ensure the performance and robustness of the overall vehicle and ESP® system.

Albert Lutz, Fabien Macaire, Walter My

The Test and Analysis of Car’s Brake Noise

With the development of the car industry and the rising of consumer’s requirements for comfort, brake noise gradually becomes one of the important factors to appraise the comfort of vehicle. This paper, aiming at solving the noise problem of the passenger car, researches the mechanism of brake noise’s generation and the ways to optimize it in order to reduce the noise. The brake noise is tested according to the road test standard. The frequency and intensity of the noise are recorded in the vehicle test. At the same time, the relation of speed and the noise’s frequency is recorded. The brake noise is divided into Squeal noise and Groan noise based on the test results of the car. Squeal noise: It is important to collect more information in the dynamometer which used suspension assembly to analyze the character of noise. The noise mechanism is analyzed and the optimum direction is found through the computer CAE technique. Groan noise: Based on the calculation and analysis of the test results, the main influencing factors of the noise are found and the optimum scheme is designed. Finally the performance of brake noise is validated in the dynamometer and the vehicle test. Computer analysis and test results show that Squeal noise is caused by the resonance of the brake system. In this paper, brake noise is reduced by reducing the stiffness of the brake disc by an average of 5 %, optimizing the inherent character of the brake system and improving the stability of the brake system. Based on the test and the analysis, the main cause of the Groan noise is that the structure of brake pad and brake disc’s ventilation is designed with defects. Groan noise is related to the structure of brake pad and brake disc’s ventilation. It is effective to reduce noise by optimizing brake pad’s structure.

Qinghai Sui

Thermal Management Simulation of Passenger Car with Naturally Aspirated and Turbocharged Gasoline Engine

The passenger car thermal management is studied in this chapter by simulation method. The underhood air flow is simulated by CFD in order to optimize engine cabin layout. The whole cooling system is modeled by 1D flow simulation in order to matching the critical components in the system. The thermal analysis is carried out by the coupling of 3D CFD and 1D simulation including radiation. The two type of gasoline engines -naturally aspirated (V6 PFI 3.0L) and turbo-charged direct injection (TGDI 2.0L) are layout in the same car underhood separately, and both have good thermal management performance. The thermal balance test and temperature measurement are carried out in order to validate the simulation.

Haie Chen, Hongzhou Li, Xinxin Dai, Qun Chen, Kang Li

Testing of Components, Systems and Full Vehicle

Frontmatter

Research on User Vehicle Operation Regularity

Engineering Questions and Research Objective

During vehicle development, engineers often set vehicle design targets based on the reports from market investigation, benchmarking, testing or users’ feedbacks. However, such reports, which can not provide quantitative, accurate data on vehicle running information, may cause over-design or insufficient design problems. In this paper, a method on how to collect vehicle running information and analyze user operation habits and cars’ running regularity is researched in order to solve the problems.

Methodology

By investigating engineers’ requirements and vehicle specifications, the information collection scheme was determined and analysis arithmetic was designed. Secondly, according to collection requirements analysis and network capacity analysis, the on-board information collection device was produced and background service system was built. Thirdly, database was established using the collected vehicle running information. Fourthly, vehicle operation regularity and user driving habits was found out by submitting enormous data to arithmetic program and analyzing it.

Results

Vehicle running analysis model was made and database was built. Analysis results provide the basis for vehicle top-down design and design improvement.

Limitations of this study

Due to the limitation number of vehicle samples, the analysis results represent only part of vehicle running information. What does the paper offer that is new in the field: The device can comprehensively collect signals from CAN/LIN BUS and from various sensors. The acquired data can be packed and uploaded to sever via 3G network.

Conclusion

This study proved the methodology of vehicle running information collection and data process is feasible. The device could not only collect and store plenty of data, but also upload the data files to sever. By using the arithmetic program, data could be analyzed. The analysis results of user operation habits and vehicle running regularity provide important references for vehicle design. For long-term work, consistent and extensive collection work needs to be done in order to acquire more accurate statistical data.

Zhonggao Yu, Yutan Zhang, Yonghong Xu, Gan Chen, Jianguang Zhou, Jianxian Chen, Jie Bai

Acoustic Mode and Structure Mode Analysis of Heavy Duty Truck Muffler

To reveal the muffler acoustic performances and structure vibration characteristics, the computational fluid dynamical (CFD) model and finite element method (FEM) model were established. Acoustic analysis results show that the muffler not only has complex acoustic vibration modes, but also the mode frequency approximately equals the engine’s incentive frequency at rated speed, so the resonance may occur and the noise eliminating effect will be reduced. Structure vibration modal analysis shows that the muffler system has high natural frequency and the natural frequency is widely distributed. So while the engine runs at rated speed or idling speed, its natural frequencies are close to the engine exhausting incentive frequencies. It is the main cause that the muffler cannot reduce the noise effectively and needs further optimization.

Guoquan Wang, Cheng Zhao, Liangcheng Zhang, Yong Chen

Transient Thermal Measurement of Electronic Components and Radiometric Characterization of LEDs

Changing requirements for HEVs and EVs (e.g., for IGBTs) and automotive lighting with LEDs are forcing component manufacturers to re-think designs, moulding techniques or packaging strategies. These changes can result in new unknown thermal behaviours that could lead to bad thermal characteristics, delamination, increased thermal resistance and failure. This chapter will address how thermal and radiometric testing and measuring to obtain accurate thermal characterization helps to increase component reliability. We used thermal and radiometric testing and measuring software/hardware products (T3Ster and TERALED) to obtain thermal characterization data of various electronic semiconductor components such as LEDs, IGBTs, and different chips for thermal simulation to understand the thermal and radiometric behaviour of the design to be able to eliminate the risks of component failure before production and also to deliver accurate thermal characterization data for thermal simulations. We obtained high-accuracy thermal and radiometric measurement values of LEDs with repeatable results. The radiometric measurements of LEDs enable a detailed characterization of various parameters, such as radiant flux and color coordinates depending on current and temperature. With this information, we were able to make selections from different vendors after researching the aging effects on these components and therefore their quality. In other tests, we were able to determine component and assembly defects that can appear either because of aging or during manufacturing of the component or the assembly, which results in changes in thermal resistance and worsens the thermal behaviour. The transient thermal measurement of electrical components is limited to semiconductor-based electrical components and their assembled state on the PCB in its environment. This chapter shows a new technology with never before reached accuracy of thermal and radiometric coupled characterization of semiconductor components that helps ensure designing and manufacturing best-in-class components and high reliability systems that use such components. A detailed thermal characterization enables optimized thermal design of the system rather than over-designing the system for thermal performance. With additional LED radiometric characterization, the same can be done for optimal performance of LEDs. This is especially important in future EV and HEV where energy consumption is critical to a higher efficiency and extended range of the vehicles.

Boris Marovic, Alexandra Francois-Saint-Cyr

Maneuver-Based Testing of Integrated, Highly Interconnected Safety Systems

Active safety and passive safety were long viewed as separate entities of automotive safety systems, while current trends point toward networks and integration. In addition to signals from the crash phase, modern passive safety systems use pre-crash information from other systems (such as ESC). This new system interdependence leads to new development requirements. Whenever communication takes place across several levels such as different bus systems with many bus participants, reliability and data consistency have to be assured at all times. Network intensification and a large number of variants dramatically increase the complexities of fault protection and control unit tests during the development process. This requires new types of test systems with corresponding interfaces and advanced simulation tools for efficient, cost-effective and seamless testing. The test system presented here uses highly capable vehicle dynamics and driver simulations with integrated crash data and fault feed-in. Normal driving conditions as well as pre-crash and in-crash scenarios were implemented to conduct a realistic test (illustrated here by the example of a safety control unit). The test was run by defining the corresponding driving maneuvers in extensive test catalogs, analogous to real-world tests. This creates the basis for a highly capable, seamless test platform. In addition, testing depth and fault detection probability can be significantly increased through a flexible and comprehensive selection of test cases.

Kathrin Sattler, Andreas Raith, Thomas Brandmeier, Christian Schyr, Daouda Sadou

Studying of Instantaneous Emissions Character for Hybrid Electric Vehicle

By testing hybrid electric vehicle emissions under a variety of driving cycles, collect instantaneous emissions, battery current and the output voltage data and so on, and analyze these data to study emission characteristics of hybrid electric vehicle. The results showed that: this hybrid electric vehicle has many complex working modes, automatic start-stop technology can adopt about 7.2 % of carbon emissions, accelerating the warm up of engine is an effective means to reduce emissions further.

Nie Yanxin, Du Baocheng, Wan Peng, Xie Jingsi

Effect of Cryogenic Treatment on Retained Austenite and Fatigue Life of Gcr15 Wheel-Hub Bearing

Research and

/

or Engineering Questions

/

Objective

There are many domestic enterprises that produce auto-hub bearings in China. But the majority of products are only applied in the after-sale market as the unstable quality of the domestic products can’t meet the OEM’s requirements. In order to improve fatigue life and dimensional stability of GCr15 steels, the cryogenic treatment was introduced to control the percentage of retained austenite of GCr15 bearing steel.

Methodology

The correlation between cryogenic treatment parameters and microstructure of the hub-bearing was studied. The percentage of retained austenite after different cryogenic treatments was measured by X-ray diffraction experimental. The equation was established to reveal the relationship between the percentage of retained austenite and cryogenic temperature. Finally, the fatigue life was performed by strengthen test according to JB/T 50013-2000 test rules of life and reliability of rolling bearings.

Results

After cryogenically treated in −40, −80, −120, −160, −196 °C chamber for 2 h, the investigation revealed that the retained austenite of the specimen surface is with proportional to the temperature decrease of deep cryogenic treatment. The specimens possess the maximum hardness and the minimum impact toughness during keeping at −80 °C deep cryogenic treatment temperature.

Limitations of this study

This study work has verified that the cryogenic treatment can improve the fatigue life and dimensional stability of wheel hub bearing. In order to obtain broader application and promotion, it requires further investigation on the characteristic properties of cryogenic treatment to be applied to

other

automotive bearings and

other kinds of

parts.

What does the paper offer that is new in the field in comparison to other works of the author

Since the mechanism of cryogenic treatment is not yet to be understood very well, So in general cryogenic treatment is still in the dormant level at present. In this study, we focus on investigating the mechanism and optimizing parameters of cryogenic treatment

to

improve the fatigue life of wheel-hub bearing.

Conclusion

The test results indicate the cryogenic treatment can improve the fatigue life of DAC 4007040 hub bearing, which runs 39.537 million revolutions, Re = 99.22 % by optimizing cryogenic treatment. In the same load conditions, the fatigue life of DAC 4007040 hub bearing subjected to conventional heat treatment is only 21.79 million revolutions in average, Re = 96.7 %.

Qiucheng Wang, Xiaobin Ning, Qi Chen, Bintao Mao

A Study on Analysis Method of Motion Characteristics in the Crash Test Based on Computer Vision

The actual vehicle crash test is the most basic and effective method in the development and validation of comprehensive vehicle safety performance. In the actual crash test, the optical measurement system can significantly record the motion form change through images on each target point. The image after-treatment can be performed by using the photographic measurement technology based on computer vision. The accurate motion characteristic information of the target points can be obtained through bundle adjustment of a series of frames, 3D photogrammetry and target tracking, as well as related calculation. The experimental results conducted at Zhejiang Key Laboratory of Automobile Safety Technology indicate that this method can particularly describe the motion characteristics of bodywork and dummy in the crash test with high sensitivity, quick speed and more data acquisition, thus satisfying the development requirements of vehicle safety performance.

Guohua Cao, Gang Han, Weiguo Liu, Fuquan Zhao

Study of Optimized Tuning in Full AFLS Head Lamps

Full AFLS (Adaptive Front Light System) is just on time headlamp-technology about varying driving-circumstances and vehicle speed using communication between vehicle’s ECU and Headlamps’ ECU. The objective of this study was to investigate optimized tuning method of AFLS headlamps in the real each car and matters that should be focused on.

Doohyun Kim

Improvements in Test Protocols for Electric Vehicles to Determine Range and Total Energy Consumption

As electric vehicles have entered the market fairly recently, test procedures have not yet been much adjusted to address their particular features. Mostly EVs are tested the same way as the ICE-driven cars with the exception that determining range is also part of the procedure. However, the current procedures address mainly primary energy consumption, i.e. energy needed to propel the vehicle, whereas the secondary energy, like energy used for cabin heating, cooling and ventilation, is not accounted properly. Main reason is probably the fact that a large proportion of this energy is catered by the waste or excess energy, but in an EV also this part of energy uses is drawn from the battery. Therefore, range of an EV may differ fairly strongly depending on ambient conditions, as in adverse conditions secondary energy use may rise considerably. Furthermore, unlike propulsion energy use that is mainly dependent on driving speed, secondary energy use is mostly dependent on ambient temperature and driving time, and energy is spend even when the vehicle is stopped. However, the challenge to determine a procedure that would more properly address the various parameters that affect range is quite substantial. Also any laboratory test procedure is always a compromise, because it is not possible in practice to replicate the real-life driving completely. Therefore, the authors call upon the engineering community to work on this subject. This chapter outlines our attempt to address this issue, and presents data from in-laboratory testing at normal and low ambient temperatures. It was found that cold driving at −20 °C ambient can shorten the range by about 20 %, even without cabin heating engaged, compared to normal ambient conditions. Using the electric cabin heater will shorten the range further by about 50 % in urban driving and some 20 % in road-type of driving with higher average speeds.

Juhani Laurikko, Jukka Nuottimäki, Nils-Olof Nylund

New AMFM Test Method with Android Operation System

With the rapid evolution of Android system, a portable, low cost, self developed test device become possible. The vehicle engineer will be able to use the cell phone with Android system and portable test kit to do the vehicle level test. There are many possible applications, one of them is the AMFM test application. Compared with the traditional test method, there are some advantages. First of all, the cost of the test device is considerable lowered. With the traditional test method, an electrical tune table is required to test the signal strength in 360°. The tune table, including the mechanical, electrical and fundamental part, costs twenty to thirty thousand USD. Maintain cost shall be additionally considered. Android test system will be an application installed in infortaiment head unit. The embedded compass will record the orientation and link the test result. Tune table will be replaced. Secondly, the inconvenience of the traditional test is remarkably relieved. The tune table is a huge, expensive device, so it has to be established in proving ground. Normally speaking, proving ground is several hundred miles away from technical center. In addition, engineering vehicle is strictly prohibited to access freeway. It makes the test very inconvenient. Without the tune table involved in the test, engineer may find a place much nearer to the technical center, and do the test whenever needed. Last but not least, the flexibility of the test content is tremendously improved. The traditional test device provides some interface to engineer, but there is no way for engineer to give any suggestion. Android system provides many accesses to programmer, who may be a contractor or a supplier working with engineer together, so it’s possible for engineer to design the test content, formula, and interface.

Yongqing Zhu, Kerun Xu, Lubing Zeng, Minjie Tian, Chendong Wang

Subjective and Objective Evaluation of Performances

Frontmatter

Ergonomic Evaluation System for Vehicle Package

In the early days of automotive products design stage, validation of the package program primarily through the 3D virtual environment, and the 3D virtual environment is not virtualization specific enough and overall image; At the same time in the mid-term product development stage, rapid prototype production is completed, additional pay for rapid sample fixture to complete the production, transportation and installation, re-use is very low; Based on this, in order to validating the package program environment during the early days of automotive products design stage, in order to providing a platform for rapid sample during the mid-term product development stage, we need Ergonomic evaluation system. We have an introduction about the Ergonomic valuation system’s research content, the Ergonomic valuation system should simulate the driver environment and other situation; including comfort machine, visibility, reach, entertainment establishment, including seat, paddles, steering wheel, console and so on. The Ergonomic valuation system’s characteristics include multi-joint, high precision, enough interfaces for fast sample installation and safe for using. The Ergonomic valuation system can simulate the feasibility of ergonomic solutions in the early stages of project development; a multi-frame Ergonomic valuation system can reduce the cost of product development, because we don’t need to make the base of the fast sample as before.

Shihai Li, Yongqing Liu, Zhongxian Chen, Mengdong Mi, Hao Chen, Weiwei Du, Tingchuan Song, Huang Jian

Subjective and Objective Vehicle Tests, Two Parallel Vehicle Handling Evaluations

Subjective and objective tests have long been used for estimating on road vehicle handling, in DGA Angers, in order to address safety problems which can occur in risky configurations. On one part, objective tests are used to measure vehicle dynamics characteristics, in ISO tests and in specific manoeuvres, mainly: (1) Steady state turning at constant radius; (2) Double lane change tests. On the other part, trained drivers give ratings to vehicle handling and dynamics characteristics, in a more comprehensive way. The aim of this paper is to present completeness or links which exist between subjective and objective tests which are carried out in order to have a comprehensive evaluation of all kinds of vehicles tested in DGA Angers. With instrumented tests and ratings given by trained drivers, correlations have been researched based on available tests results in DGA Angers which is in charge of vehicle tests whose results are used for giving them driving agreement. These links are presented and discussed in this paper focused on evaluation of safety performance made on a large spectrum of vehicles.

Eric Chabrier, Michel Grima

Subjective Evaluation and Modeling of Human Ride Comfort of Electric Vehicle Using Tools Based on Artificial Neural Networks

This article presents an application of the human comfort objectification tool developed based on the Artificial Neural Networks (ANNs) to support the development of drive train system. The main objective of this study is to apply the developed tool to predict the subjective comfort rating of different driver types during the start-up procedure, i.e. the process of starting to drive from standstill with releasing of the brake and reaching of constant travel speed. In this case, test drives performed by drivers representing potential customers are carried out with a commercial electric vehicle. The subjective evaluation in terms of customer satisfaction is executed based on the 5-digit scale. During the experimental investigation, the predefined objective parameters are captured. They are the resulting longitudinal acceleration measured at the different locations of the driver seat, the vehicle velocity, the vehicle acceleration as well as the standardized courses of the accelerator pedal and the brake pedal. The human sensation modeling is carried out by determination of the relationship between the objective parameters, like the power spectral density (PSD) values of the longitudinal acceleration captured at passenger seat and the subjective comfort ratings. An ANN is applied to interconnect output data (subjective rating) with input data (objective parameters) by “trained” weighted network connections. The results of the investigation have demonstrated that the objective values are efficiently correlated with the subjective sensation. Thus, the presented approach can be effectively applied to support the drive train development of electric vehicle.

Lerspalungsanti Sarawut, Albers Albert, Ott Sascha

Torque Vectoring Control Design Based on Objective Driving Dynamic Parameters

Due to the good controllability of electric motors the possibilities of driving behaviour control are increased. The amount of applicable yaw moment on the car compared to previous systems is increased; therefore it is essential to investigate the possibilities of influencing the driving experiences. Thus the subjective impression of the vehicle dynamics can be improved although the narrow roll-resistant optimized tyres on electric cars have less lateral potential than conventional ones. The objective of this study is to find the key driving dynamic parameters to evaluate the behaviour already in the simulation and to adjust the torque vectoring control unit to improve the drivability. The vehicle dynamics evaluation of the small electric car is based on characteristic values from literature research and handling tests. Further dynamic simulations and test drives with different torque vectoring target specifications generate a range for each parameter, where the driving behaviour for the driver is still on a high level. A correlation between the objective parameters gives a detailed overview of their specific importance in different driving manoeuvres. Depending on the uncontrolled vehicle behaviour a recommendation for the design criteria of the torque vectoring control unit is given. Thus in the time intensive driving tests only the control target (the yaw rate) has to be validated and adjusted.

Michael Graf, Markus Lienkamp

Integrated State Estimation with Driving Dynamic Sensors and GPS Data to Evaluate Driving Dynamics Control Functions

The aim of this research project is to investigate the use of GPS data for test drives. Based on data of a multi-antenna GPS system and vehicle dynamic sensors, an information platform is performed. This platform includes the merged sensor signals and an estimation of vehicle states that are not measurable. In a state estimator the lateral dynamic model is combined with a navigation model. The state estimation is accomplished by coupling the signals in an extended Kalman Filter (EKF) which is a variant of the Kalman Filter (KF) for nonlinear dynamic systems. The double-track approach with a linear tire force model is used to describe the lateral vehicle dynamics. Pitch and roll movements are analyzed separately from each other. The unknown or time-variant vehicle parameters are estimated online by recursive estimation methods. In addition to the presentation of the developed methods, results from test drives with the research vehicle (BMW 540i) at the testing area of the Technische Universität Darmstadt are presented.

Markus Bauer, Carlo Ackermann, Rolf Isermann

Evaluation Tool for Current and Future Powertrains

Research and/or Engineering Questions/Objective

The paper describes a simulation tool for determination of vehicle energy consumption under dynamic conditions, suitable for early stages of design. It describes vehicle dynamics in longitudinal direction and the appropriate efficiencies of engine, transmission and accumulation components (if used). The simulation tool is targeted to the optimization of vehicle powertrains with respect to reducing the vehicle fuel consumption, CO

2

production and increasing the overall efficiency of the vehicle. It is also used to evaluate the possible benefits of new powertrain concepts. The objective of this paper is to demonstrate the possibilities of the developed tool on a comparison study of several powertrain layouts.

Methodology

The simulation tool is based on ordinary differential equations and a dynamic expandable library of vehicle component features. Various powertrain components are represented by a dynamically expandable library of component modules. Each module represents a particular component of a powertrain such as gearbox, engine, wheels, vehicle body etc. Modules may be modified to more complex models at any time or even replaced by different modules to represent different powertrain layouts. Mechanical part of the powertrain is modelled with multi body simulation approach. Particular powertrain elements are represented either by mass elements or stiffness/damping elements. Electric part of vehicle powertrain such as electric engines and battery models are based on simple circuit models and/or look-up table based models. All required input data may be obtained by targeted simulations using multi-dimensional methods or by experiments.

Results

The result of this study is a comparison of various less or more common powertrain layouts. Its aim is not to present accurate results that correspond to each powertrain type, but more to point out the advantages and disadvantages of particular powertrain types. The simulation tool itself should also be considered as a result, because it provides a powerful tool for powertrain evaluation, topology layout optimization and may be adapted for various simulation tasks.

Limitations of this study

This simulation tool is designed to provide quick initial estimates with minimal input data or to serve as a part of X in the loop (XiL) tests, where X stands usually for hardware, software, man, etc. Therefore a lot of simplifications must have been applied. However, the dynamically expandable library allows the replacement of any part of the model with a more sophisticated model if needed and thus adapt the simulation tool to various computational tasks.

What does the paper offer that is new in the field in comparison to other works of the author

This paper is more focused on less common powertrains, such as pure electric vehicles or fuel cell vehicles. Presented simulation approach is far more complex than ever before. The simulation environment is completely new as well.

Conclusion

The simulation tool that calculates quick initial estimates of vehicle qualities in a transient driving cycle was created in a specialized graphical programming language. The demand on its transparency and modularity was satisfied by a dynamic expandable library of vehicle component features. The great advantage of presented simulation tool is its low computational time and easy realization of XiL approach. Comparison of various less or more common powertrain layouts was performed with this simulation tool and its results are presented within the paper.

Barak Adam

Other

Frontmatter

Wet Handling Track: Utilities, Water System, Coefficient of Adherence

Research and/or engineering questions/objective

A Wet Handling facility must assure a regular and controlled water film depth all along the track, homogeneity and an adequate coefficient of adherence of the asphaltic surface to allow maximum repeatability on tests. The study focused on defining the parts of the track and the construction procedures required to get the proper

coefficient of adherence

and to define the

basis of the design

of the watering system. The influence on the grip of the asphalt characteristics, the aging procedure of the track and the water treatment systems were tested and studied. The layout of the track, the design of the watering and the recovery elements (pianos, drainages, run-off areas) were done to get the safest conditions without affecting the tires and their behaviour.

Methodology

The Test Facilities Engineering department at IDIADA’s Technical Centre has carried out a large number of studies on the asphalt characteristics to define the bituminous mixture and the grain size distribution of the aggregates to be paved in tracks with wet surfaces. The analysis of the cleaning, filtering and treatment systems for the water used in the track was done thinking on the influence of the presence of organic and non-organic particles on the grip. Based on the water study and on standard quality control tests, comparisons were made with the results obtained from other tracks. A procedure for aging the asphalt was studied and implemented for three months by means of repeated drive-through with test vehicles. The coefficient of adherence was measured every two weeks following internal braking procedure and complemented with the one indicated in the Regulation N° 13 ECE. The design of the watering system took into account that the watering system needed to be adapted to the “pianos” and kerb stones to keep the desired water film depth and regularity without damaging the tires or affecting test vehicle trajectories.

Results

The asphalt’s coefficient of adherence data obtained during the aging period and how this affects the results will be shown together with the test procedure used for the aging of the track, the basis for the design of the watering system and the water recovery system used.

Limitations of this study

The lack of testing regulation guidelines for these facilities gives no trustful ways to correlate the data obtained between different tracks.

What does the paper offer that is new in the field

? This new watering and recovering system designed and implemented gives an optimal control on the regularity of the water film depth along the track with a high percentage of water recovered on the system.

Conclusions

The Wet handling track utility system and pavement characteristics designed and constructed fulfil the most demanding premises in terms of water film depth regularity, coefficient of adherence of the track and water reservoir savings according to environment policies.

Pinilla Marc, Carbonell Abel, Arango Luz A

The Development of an Auxiliary Unloading Device for Dump Trucks

This chapter analyzes the roll-over mechanism of dump truck in the unloading operation, and then presents an auxiliary unloading device. The device consists of boosting mechanism and linkage mechanism. The driving force of the device originated from the geometric distortion produced in the process of lifting carriage. This chapter elaborates on the principle of device and establishes virtual prototype model of the device. Based on the established model, the validity and feasibility of the design has been verified.

Guoxing Li, Tie Wang
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