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2023 | Book

Proceedings of China SAE Congress 2021: Selected Papers

Editor: China Society of Automotive Engineers

Publisher: Springer Nature Singapore

Book Series : Lecture Notes in Electrical Engineering


About this book

These proceedings gather outstanding papers presented at the China SAE Congress 2021, held on Oct. 19-21, Shanghai, China. Featuring contributions mainly from China, the biggest carmaker as well as most dynamic car market in the world, the book covers a wide range of automotive-related topics and the latest technical advances in the industry. Many of the approaches in the book will help technicians to solve practical problems that affect their daily work. In addition, the book offers valuable technical support to engineers, researchers and postgraduate students in the field of automotive engineering.

Table of Contents

Simulation and Optimization for an SUV Cooling System

In order to solve the problem that engine coolant outlet temperature of an SUV was too high in low and medium speed climbing and high speed conditions, 1D/3D co-simulation tool were used to establish a simulation model of whole vehicle cooling system. Through test and simulation, different factors that affect cooling system thermal balance performance were analyzed. The research found out that: Independent cooling loop for transmission and engine can significantly reduce engine coolant outlet temperature. Cooling system pipe arrangement has an influence on coolant flow distribution, but has little influence on coolant temperature. By optimizing radiator type and underhood arrangement, underhood flow field characteristics can be improved and inlet air flow rate of cooling system was increased. So the cooling system capacity has been improved.

Xiang Xu, Yilun Zhang, Feng Zhao, Hucheng Yi, Yuan Wang, Junfang Xu
Modeling of Fluid-Structure Interaction to Enhance Battery Thermal Management in Electric Vehicles

Lithium battery can be considered as a high-power density energy storage device in hybrid electric vehicles. The battery’s safety, driving range and functionality are sensitive to the working temperature. Therefore, electric vehicles need complicated battery thermal management components to satisfy the performance requirement of lithium battery. Furthermore, the lithium battery capacity for mild hybrid electric vehicles is much smaller than full electric vehicles, so the air-cooling system can be considered the best choice for mild hybrid electric vehicles. Among different types of cooling performance, the other strength for an air cooling system is that it also can decrease the cost of developing a heat dissipation system in hybrid electric vehicles. At the same time, thermal diffusion around the battery cell can be considered as an obstacle for improving the convective heat transfer rate. In this study, a novel and self-agitated device that takes advantage of vortex-induced vibration is developed to disrupt the thermal boundary layer around the battery cell and enhance thermal performance. An arbitrary Lagrangian-Eulerian algorithm is developed to simulate fluid-structure interaction field to calculate the heat transfer coefficient. An air-cooling system of the battery pack is developed by using Simcenter AMESim. The AMESim model aims to verify the heat transfer coefficient calculated from the fluid-structure interaction cases, and then investigate the maximum temperature distribution. Our results demonstrate that the vortex-induced vibration by the self-agitated device can increase the heat transfer coefficient up to 46.66% compared with the traditional battery pack. The fluid-structure interaction algorithm can be used to enhance battery thermal management.

Yinsheng Liao, Haolun Xu, Taishuo Huang, Xingyang Shao, Zhiming Hu
Application of “Digital Twin” Technology in Vehicle Aerodynamic Drag Optimization

Through the establishment of a “digital twin” model, the aerodynamic drag of a vehicle is studied, built CFD twin model, simulation optimization and the DOE method was conducted, wind tunnel experiments are carried out to study the drag reduction contribution changes of the aerodynamic kit, the trend is to reduce the drag coefficient of the vehicle and verify the reliability of the results of the “digital twin” model.

Mingyang Song
Optimal Design for Cooling Fan Based on Multi-objectives with Blowing Rate and Noise

Based on sliding mesh technology, a three-dimensional numerical simulation model of cooling fan is established to investigate the aerodynamic and acoustic performances. The reliability and accuracy of the simulation model are verified by the experimental results. By analysing the aerodynamic performance of the prototype cooling fan, three improvement schemes are proposed in this study, include designing the blade with unequal spacing and adding some flow deflectors on the blades. The flow field and aerodynamic noise of the cooling fan between the prototype and optimized fans are compared by using the validated CFD method. The results show that the noise of the cooling fan can be significantly reduced under the premise of sufficient air flow. Finally, an optimized scheme is proposed for the studied cooling fan.

Ye Xiao, Wu Jingqi, Zhou Tianjun, Chao Rongjun, Li Yuan, Shu Lei, Kaku Chuyo
Chassis Bolts Axial Force Attenuation Calculation and Verification

The reason for the axle force attenuation of the chassis bolts is explained, and the calculation method of the axle force attenuation of bolts is provided. Through the calculation examples of the three chassis parts and compare with the test results of the axle force attenuation, the calculation accuracy is verified. At the same time, through the structural differences and test results of these three parts, the factors affecting the attenuation of the axial force are analyzed and explained. Accounting the test of the axial force attenuation, the tightening axial force and attenuation are quantitatively managed to ensure the bolt tightening reliability, thereby enhancing the reliability of the vehicle.

Jinquan Ye, Rui Dai, Jiankun Li
Study on the Influence Mechanism of Filiform Corrosion for Aluminum Alloy Decoration in Vehicle Interior Trim

The A8014 Aluminum Alloy decoration is studied to analyze the reason of filiform corrosion, and confirm the influence rule through Libai dishwashing mixed liquid clean the surface door trim in customer daily life. The effect factors are brushing process, film thickness, the coating on cut section, matching chrome at the accelerated condition. And base on the microstructure analysis, the four factors are analyzed for the influence mechanism of filiform corrosion, which provides a reference for the development of interior Al decoration.

Zhang Mengying, Yang Bing, Xiong Huangao
The Simulation Method of Solving the Cracking Problem of Knuckle Under the Vehicle’s Misuse Test

This paper introduce a method to simulate the fracture of vehicle’s front knuckle under the vehicle misuse test. The general idea to solve this problem is to install the wheel force transducer on the vehicle to collect the load signals of the vehicle under the vehicle misuse test, and decompose the load signals of the vehicle’s wheel center to the load signals of the hard points of the front knuckle through MBS software. However, due to the large impact load of the vehicle’s wheel load under the vehicle misuse test, the accuracy of the wheel force transducer cannot meet the requirements, and the transducer may even be damaged. Therefore, in this paper, force sensors and acceleration sensors are arranged on the internal parts of the vehicle, and the simulation method of virtual iterative is adopted to solve the load signal of the hard point of the front knuckle. The load signal of the hard point of the front knuckle is input into the FEM simulation software, and the strain distribution of the front knuckle is solved and compared with the test results. The comparison results show that the max strain of the knuckle under the simulation exceeds the strain value of the material fracture, and it is consistent with the cracking part of the knuckle under the vehicle misuse test, which validates the correctness of the simulation method.

Ding Ding, Xu Zhi, Han Guangyu, Zhang Yongren, Qi Xuejun
Application of New Fatigue Damage Theory in Reliability Design of Automobile Components

A new cumulative fatigue damage theory is established in this paper. Under the premise that the known conditions and the convenience of application are the same as Miner theory, which is the most widely used at present, the new theory successfully solves two basic problems of fatigue: (Measure the load spectrum block of the component in a certain period of working time. ① Calculate the failure probability of the component when it works to the specified time. That is, the failure probability of the component subjected to the specified cycle period of the load spectrum block. ② Calculate the working time of the component under the specified failure probability. That is, the number of cycles of the load spectrum block that the component can bear under the specified failure probability). The new theory has been applied to the fatigue life prediction of various automobile load bearing components, and satisfactory results have been obtained.

Wang Wenge, Lu Yanhui
Proving Ground Correlation Method Based on Optimized Particle Swarm Optimization Algorithm

In the process of vehicle durability development, it is necessary to accelerate the durability test verification at the proving ground. It is particularly critical to optimize and formulate the proving ground durability procedure scientifically, efficiently and accurately. Based on the Miner linear cumulative damage theory and the road load spectrum data of the proving ground, in this paper, the sub-band damage equivalent proving ground correlation model is constructed, using the optimized particle swarm algorithm, to study the proving ground correlation technology based on frequency domain damage, and finally the rain flow count is adopted to evaluate the accuracy of correlated calculation, with the damage quantification method. The research shows that this method is scientific and reasonable, the correlation calculation efficiency is high, the correlation channel and the verification channel have good correlation in the frequency domain damage and rain flow count, and the frequency domain damage retention ratio is between 50% and 200%. The efficiency and accuracy of the correlated calculation can reach the expected goal of the proving ground correlation, and the solution results can be flexibly constrained by the actual driving route. It can be applied to engineering implementation directly.

Qiangqiang Dong, Pengxiang Hao, Jiansen Yang, Ran Guo, Xiao Feng
Research on Equivalent Relationship Between Constant Amplitude Bench Test and Road Test of Top Mount

The top mount is a component bonded by rubber and metal vulcanization, which is used to connect the shock absorber assembly with the body, alleviate the impact from the road to the body, attenuate the vibration caused by it, and ensure the comfort of the passengers. At present, the bench test of the rubber part is mainly based on the constant amplitude loading bench test, which is mostly used for comparative analysis. The corresponding relationship with the road test is unknown, so it is impossible to predict the life of the part on the whole vehicle. Based on the theory of linear fatigue cumulative damage, the correlation between the test of the top mount and the random test of load spectrum is obtained, and the equivalent relationship between the equal amplitude bench test and the road test is obtained.

Zhang Yong, Yue Yi, Li Lun, Zhang Yuehui, Xu Tingting
Fatigue Assessment of Advanced Coach Structures with Welding Seams Based on the Experiments and FEA

The study of coach welded structures durability based on the tests and FEM Numerical simulation was carried out. First, the tension-compression fatigue tests with welded joints were carried out. The steel S-N curves which will be used in the FEA fatigue analysis were gained; The finite element models of weld structure has been built and the fatigue analysis of welded joints were taken out, the comparison between fatigue test results and the FEA simulation results was performed, the results of both methods showed very closed and the verification of FEA weld seam model which was built in the FEA; Finally, the FEA model of coach with welded joints has been established, the number of seam welds reached at 3870, the fatigue analysis of the whole coach has been carried out. The research can be used for coach or bus fatigue analysis of high cycle in welded joints of profiles with thin wall tubes.

Nie Wenwu
Warranty Data Prediction and Research for Automobile Based on Weibull Distribution Model

According to the automobile warranty requirement, the warranty data predicting method of automobile by using warranty records was proposed. Firstly, the Weibull distribution was established based on the preprocessing of warranty data; secondly, the reliability was analyzed and predicted by using parameter characteristics and probability diagram, at last, some vehicle warranty data was taken an example to verify the practicability and effectiveness of proposed model and analysis method according to errors of forecast method, which could provide analysis and improving bases of further improvement.

Jia Liu, Gang Liu, Yuanjian Zhang
Optimization Design of Welding Seam for Axle Housing Baseed on Fatigue Life

The reasonable optimization of welding seam load is of great significance for improving the overall fatigue life of punch-welded axle housing. Taking the welding axle housing of passenger car as the research object, the stress distribution of the housing and the welding bracket was calculated by the finite element method (FEM), and the fatigue stress spectrum was obtained. On this basis, the fatigue damage of the housing, the welding bracket and the welding seam was predicted using the critical plane method and the notch stress method, and the rationality of the welding seam layout was evaluated by the fatigue damage of the welding seam. Then, the mechanical analysis was carried out for the welding seam with large fatigue damage, and the optimization measures were put forward from the weld position, length and welding bracket stiffness, so as to improve the local load state of the welding seam. Finally, the fatigue life calculation and experimental verification of the optimized scheme were carried out. The results show that compared with the original scheme, the fatigue damage of the optimized scheme is reduced by 43.0%, and the overall life of the housing is greatly improved. The optimization scheme has passed the bench durability test and vehicle road durability test, and the housing has no fracture or crack, which verifies that the optimization scheme is effective, and the weld optimization measures have certain engineering reference value. Compared with the bench fatigue durability test, the prediction accuracy of fatigue life is 82.4%, which meets the engineering needs.

Kang Yipo, Zhu Xuewu, Zhang Youlong, Yan Bo, Li Junlou, Liu Yanling
Random Vibration Fatigue Analysis and Optimization of Vehicle Wheel Speed Sensor Bracket

The wheel speed sensor bracket of an electric vehicle was fractured during the vehicle road durability test. The reasons such as material and system layout were excluded, and vibration fatigue of the bracket was focused on. Simulation analysis was carried out with the load spectrum collected in the proving ground, which further indicated that the fracture of the bracket was the result of random vibration fatigue. An optimized structure was proposed aiming at increasing the natural frequency values in magnitude. The result comparison of the accelerated vibration tests revealed that random vibration fatigue was the true cause of the fracture of the wheel speed sensor bracket. Vibration fatigue characteristic of the optimized structure was remarkably improved. The optimized structure has passed the vehicle road durability test.

Xu Wang, Chao Han, Chu Teng, Jiaxing Sun, Wenchao Zhou, Jiaming Chen
The Random Vibration Analysis and Optimization of MCU of a HEV Transmission

MCU of a HEV transmission was failed in random vibration test, the failure form is manifested in foot desoldering of chip solder and cable base on the control board. According to the structural characteristics and random vibration test conditions of the MCU, a finite element model of random vibration was established. Through random vibration analysis, the critical modal frequency that cause vibration failure was found, and the maximum RMS of the analysis result is also consistent with the test failure location. On this basis, two optimized schemes of B and C are proposed. The simulation indicates the RMS stress of the soldering foot of the cable base of scheme C reduced by 13%, the RMS stress of the chip soldering foot is reduced by 23%, therefore, the vibration stress at the failure location is significantly improved. The verification scheme made according to C successfully passed the random vibration test, the improvement reached the expected effect.

Chao Liu, Xin Li, Xiangwang Li, Xiong Wang, Fengqin Huang, Zhiming Zhang, Wenlong Zhang
Vibration Diagnosis and Control Research of a Car Luggage Door

The abnormal vibration in the vehicle driving process is an important reason of abnormal noise, parts fatigue and structural strength damage; it has important influence not only on the vehicle comfort, but also on the safety. In this paper, the diagnosis, control and structure optimization of the abnormal vibration of a car luggage door were carried out. The operational mode analysis and the operational transfer path analysis were applied to determine the abnormal vibration reason and the vibration transfer path with higher transfer rate, and the most sensitive structure to the abnormal vibration, the luggage door hinge, was determined. Then the structure of luggage door hinge was optimized to enhance the important order natural frequency of luggage door, to avoid resonance with the road excitation. Simulation calculation and vehicle test showed that the optimization results were remarkable. In order to avoid the fatigue strength problem, the fatigue strength of the optimized luggage door was calculated and tested; the results showed that the optimization hinge had no effect on the fatigue strength.

Yan Long, Lingshan Jiang, Xueqiang Liu, Zhixin Yao, Dan Song
Analysis on the Influence of Structural Adhesive Length on Torsional Stiffness of Body-in-White

The application of structural adhesive can effectively improve the structural performance of body-in-white, reasonably arrange and optimize structural adhesive, improve body-in-white performance, reduce and reduce thin steel plate, replace solder joint and so on. In this paper, taking the performance improvement and lightweight as the optimization goal, the structural adhesive layout analysis method of CAE topology optimization is used to optimize the structural adhesive design. Thus, the key area of performance is identified and the structural adhesive is arranged here, and finally the stiffness of body-in-white is improved. In this paper, combined with the performance requirements of a certain vehicle model, the structural adhesive length of the body-in-white is optimized and analyzed, and the reasonable structural adhesive length suitable for a certain vehicle model is confirmed. Finally, the torsional stiffness of body-in-white is improved by 1384 Nm/deg, fatigue problems are solved in 6 places, and the collision performance is improved; at the same time, the weight of body-in-white is reduced by about 3.95 kg.

Chao Li, Jun-ping Qiao, Long Wan, Jing-ru Bao, Jian-wei Yang, Dong-sheng Zhang
Design and Development of Automobile Hydraulic Servo Test System

The test bench driven by hydraulic servo has been widely used in the test of vehicle and parts, and plays an important role in automobile material test, new material research and development, product part structure design and quality monitoring. The mainstream suppliers in the field of automotive high-end hydraulic servo test equipment are foreign manufacturers, with serious technical blockade, difficult maintenance, long procurement cycle and high price of equipment body and accessories; in order to improve the test efficiency of automotive products and reduce the test cost, a set of high-precision automotive hydraulic servo test system is developed independently. Based on the basic principle of hydraulic servo control, the test system independently developed the test software, control accuracy reached the level of first-class hydraulic servo equipment, completed the fatigue life test of truck saddle, and provided guarantee for the performance and life test of subsequent vehicle and parts.

Mingyu Cui, Chunhui Yang, Fuqiang Liu, Yulei Wang, Hongdong Li
The Closed-Form Equations of Motion of a Snake Robot with Coulomb Friction Force

A complete formulation of the equations of motion of snake robot locomotion is presented. The equation is in closed-form (i.e., analytic form) which explicitly describes the input-output relationships in terms of independent variables. It includes the dynamics of the unconstrained motion, the constraints, and the Coulomb friction forces induced by the constraints. The salient feature of the equations of motion is that it is only based on the physical variables which configure the motion. No auxiliary variables such as Lagrange multipliers or pseudo-generalized speeds are needed. Therefore, the equations of motion are most suitable for control design and generic dynamic analysis.

Huang Qingmin, Huang Jin, Li Xingyu
Design of Intelligent Factory Line Integrated Management System

Production line management is very important for the automotive industry, excellent and healthy production line is the basis for enterprises to improve production capacity. In this paper, a digital production line production management system was built based on the workshop Internet of things platform. The network and data of field equipment in automobile welding workshop were collected, with MES (manufacturing execution) system as the core. Manage and control manufacturing resources, plans and processes such as production, equipment, quality, reports, personnel, intelligent lighting, energy, and early warning systems. Real time data exchange was carried out at all levels of the plant, so that the information flow of decision-making, execution and control can be closed-loop. Through the design of this system, the intelligent level of production line management could be improved, which provided a new idea and method to realize all-round digital and intelligent transformation of automobile production line.

Jianzhuang Du, Guangquan Kang, Shi Qiao
Design and Application of Automatic Paint Marking System Based on Big Data of General Assembly

The rapid development of industrial Internet and big data information technology has become an important force to promote the intelligent upgrading of automobile assembly. Through the integration of production equipment and IT, the establishment of the whole process data acquisition and analysis system, and the creation of digital assembly plant are the effective ways to realize the “quality and efficiency improvement” of vehicle production, and also the effective means to “ensure the competitive advantage of products”. As a general means of vehicle assembly process confirmation, paint marking shoulders the important responsibility of process control and quality confirmation. At present, major vehicle factories use manual paint marking to carry out this operation. There are often problems such as missing identification, ambiguity and breakpoint, which bring some obstacles to quality management and problem analysis. This paper describes the status quo of paint marking process under the background of intelligent transformation of general assembly, and puts forward a construction scheme of automatic paint marking system based on big data technology, which can realize the standardization of painting marks and traceability of results, and provide a force for the collection of information in the whole process of vehicle production.

Taihua Chu, Peng Lu, Lianhui Feng, Liguo Cong, Yimin Zhu
Research the Position Design of the McPherson Suspension Anti-Roll Bar’s Linkage on the Steering Performance

In the article, the interference of steering torque which produced by the McPherson suspension Anti-Roll bar’s linkage has been analyzed, the conception of equivalent steering moment arm is introduced to quantitatively analyze the influence. By setting the different position of the Anti-Roll bar’s linkage, the effects of different equivalent steering moment arm values on the suspension wheel jump steering performance and the vehicle dynamic steering characteristics are compared and analyzed. After collecting the statistical analysis of the equivalent steering moment arm value of several front McPherson Anti-Roll bar’s linkages, recommend the reasonable equivalent steering moment arm value for different vehicle types, provide an effective data for guiding the suspension Anti-Roll bar design.

Wenyuan Wang, Youbing Lin, Zuping Deng
Suspension Friction Mechanism Study and Friction Optimization

Suspension friction has a great influence on ride comfort of vehicles, especially under the excitation road condition of micro-amplitude and high frequency. In this paper, McPherson suspension is taken as the analysis object, the mechanism and composition of suspension friction are analyzed, the suspension friction prediction model is established, and the contribution ratio of each part to the suspension friction is obtained. By comparing with the experimental value, the model prediction is in good agreement with the experimental value. At the same time, shock absorber friction whose contributions is biggest to suspension friction is optimized, study result shows that by reducing air surface angle and the interference fit of the oil seal lip, can significantly reduce friction force between oil seal and the piston rod, and, by optimizing the spring load axis angle, can significantly reduce the shock absorber lateral force, so as to reduce the friction force of shock absorber of reciprocating motion. Finally, the experimental evaluation results show that the decreasing trend of suspension friction is consistent with the predicted model. At the same time, the subjective evaluation results and objective measurement data after optimization of suspension friction shows that the ride comfort in high-frequency excitation road surface (3−20 Hz) has greatly improved.

Mao Lichen, Sun Guangyong, Wang Keke, Li Jiehong, Qin Wei
An Objective Evaluation and Design Method for the Part Pedal Power Performance of Vehicles

In the process of vehicle development, the development of the Part Pedal Power Performance that can better reflect the actual driving conditions is becoming more and more important. This paper analyzes the key influencing factors of the Part Pedal Power Performance, proposes a subjective and objective evaluation project of the Part Pedal Power Performance, uses acceleration response surface to analyze the vehicle longitudinal acceleration characteristics under different pedal position and speeds. Establishing an objective evaluation method of the Part Pedal Power Performance and guiding the optimal design according to the objective evaluation results is a beneficial supplement to the subjective evaluation which pointing out problems and solving problems. It has a certain guiding significance for vehicle development.

Xiaoyan Liu, Yanding Yang, Xiaoming Ye
Research and Improvement on Protection of the Occupants of a Light Commercial Vehicle Cab

In the process of upgrading and developing the cab structure of a light vehicle, the CAE simulation shows that the initial cab structure does not meet the requirements of test B: A pillar impact test in GB 26512-2021 “The protection of the occupants of the cab of commercial vehicles”. In order to improve the crashworthiness, the load transfer paths are distinguished, and the weak links are obtained to perform the improvement plan. The maximize deformation and the final deformation during the impact simulation are used to check the survival space. These crashworthiness evaluation indexes can ensure the accuracy of the results between the CAE simulation and the test. The CAE simulation is used to testify the performance of the improvement plan, and the improved cab passes the test B: A pillar impact test at once. The test results demonstrate the rationality of the improvement plan and the accuracy of the CAE simulation. The improvement methods of the cab crashworthiness in this paper can provide a necessary reference basis.

Nan Song, Yiwen Li, Weitian Yi, Weimin Gu, Chongxiao Yang, Tiebin Bai
Experimental Research of Thermostat Diagnosis for Light Vehicle Cooling System

China’s 6th emission standard (N6) has required OBD system should monitor whether the thermostat is working properly, compared to Emission regulation N5. In this paper, a strategy of thermostat diagnosis was introduced and experimental research of thermostat diagnosis development was executed from three aspects of performance test, vehicle verification, and further development. The main contents are the development and performance calibration of thermostat diagnosis based on N6, including factors, extreme environmental road tests (high temperature, high altitude, and high cold), and diagnosis characteristic of thermostat under CLTC condition, which would be adopted in N7 in the future. The diagnosis performance developer could fully understand and coordinates the related factors of thermostat in advance. It helps to reduce repeated calibration during the development process and to improve the quality and efficiency of the development.

Hai Li, Yongjun Liu, Hualong Li
Low Temperature PEMS Emission Control Study of Commercial Vehicles

In this paper, we studied the N3 commercial vehicles meet the China VI b standard. When vehicle at −7 ℃ low-temperature and light-load PEMS test, the engine of China VI a cannot achieve the China VI b standard requirements. The N3 vehicles can meet the China VI b standard by improving engine exhaust heat management and optimizing original emission in engine. Optimal exhaust temperature management can increase the engine WHTC exhaust average temperature by 25 ℃, the NOx emission decrease by 30% in part load, by the way the N3 class vehicle can achieve China VI b standard. Engine exhaust thermal management and EGR technology will be important for future emission regulatory requirements.

Dalu Dong, Qi Yu, Yi Zhang, Hongming Tian, Zhen Wang, Yupeng Wang
Effect of Rotor Excitation on Order Noise of Permanent Magnet Synchronous Motor

Only the electromagnetic force on the stator is applied when calculating the radiated noise of permanent magnet synchronous motor (PMSM) in the industry. And the influence of rotor excitation on the noise of PMSM is not considered. This paper studies the loading method of rotor excitation firstly. The centralized force is applied to the rotor which simplified with superelement. Secondly, the modal results of the motor assembly simplified with superelement are compared with the modal results of the motor assembly without simplified. The correctness of simplifying the rotor with the superelement is verified in this paper. Finally, the motor noise under three working conditions is calculated. The comparison results show that the rotor excitation has little effect on the main order noise of the PMSM. The reason why the rotor electromagnetic excitation is not considered when calculating motor noise in the industry is answered.

Cai Hui, Niu Wenbo, Gang Longyou, Tang Lechao, Guo Shoulun
Whine Analysis and Reduction of Gearbox on EV

This article introduces gear whine at 720 Hz when motor rotates around 4880 rpm/min. Test result shows that motor control unit (MCU) shell’s vibration is the largest around 720 Hz among several points, much larger than that of source vibration (gearbox). Therefore, there is a conjecture that the whine is mainly radiated through MCU shell and a butyl rubber is added to this shell to demonstrate this conjecture. Road test result shows that the whine reduces about 10 dBA, thus that the shell has great influence on the whine is demonstrated. A shell, whose thickness is 5 mm (called ‘shell B’), is adopted to reduce the whine and road test result shows that the whine deteriorates. Shell B’s natural frequency is 678 Hz, close to the frequency of whine. Therefore, it is possible that shell A and the whine resonate when motor rotates at 4880 rpm/min. This conjecture is demonstrated by a shell whose thickness is 4 mm (called ‘shell C’). The durability test of butyl rubber is done subsequently, and the three countermeasure (C/M) are compared, and butyl rubber is chosen as the final C/M. This article could give a guidance for analyzing and reducing the whine of gearbox.

Yueyun Zuo, Feng Deng, Junqing Gu, Shangbao Fei, Jianwu Chen
Design and Verification Analysis of IGBT Bridge Arm Direct Active Discharge Circuit

This paper presents two different control circuits for active discharge by IGBT, which can control the turn-on voltage of IGBT on the upper arm to make IGBT work in desaturation region under the condition of active short circuit of IGBTs on the lower arms, and the energy stored in the capacitor can be converted into the desat energy of IGBT to deplete. The junction temperature of IGBT was measured by infrared thermometer. The results show that both of the proposed control circuits can safely and effectively control the IGBT direct active discharge, and ensure that the junction temperature of IGBT is within the safe working temperature range.

Li Zhengwen, Zhang Huizhong, Li Qiguo, Chen Yanzhi
The Study of Micro-channel Methanol Steam Reforming for On-Board Hydrogen Generation

In this paper the micro-channel methanol steam reforming reactor was studied, which one was designed to generate hydrogen, and the generated hydrogen was used in the vehicle fuel cells, especially in the high temperature proton exchange membrane (HT-PEM) fuel cells. Computational fluid dynamic simulations and experiments were carried out to investigate the performance of the micro-channel reactor under different design parameters. Through the combination of the numerical computational fluid dynamics simulations and the experiments, the performance of the micro-channel reactor was studied from the fluid flow characteristics (the fluid flow uniformity and the pressure drop) and the hydrogen production performance (the kinetics of the steam reforming reaction). The results indicated that the velocity uniformity coefficients in the inlet zones of the oxidizing side and the reforming side are high, the fluids inside the micro-channel reactor are uniformly distributed. The reaction to produce hydrogen from the methanol aqueous solution in the micro-channel reactor was simulated and tested, it indicated that the content of the reformed gas can meet the requirements. In addition, the temperature uniformity inside the micro-channel reactor was improved by adjusting the inlet temperature of the reforming side and the air volume of the oxidizing side.

Yu Jiao, Qi Zhaoyang, Shen Jianyue
Bipolar Plate Flow Channel Design, Optimization and Influence Level on Performance of PEMFC

With the intensification of environmental damage and climate change due to conventional energy and power systems, alternative clean and sustainable energy and power technologies need to be developed. There is an urgent requirement to commercialize the Proton Exchange Membrane Fuel Cell (PEMFC) with its low operating temperature, high-efficiency and near-zero pollution. The paper has established a single-channel PEMFC hydrodynamic model that includes flow and mass transfer equations, electrochemical reaction model of the catalytic layer and water transfer model. The effects of cross-sectional shape, channel depth, and width have been simulated and analysed. The most appropriate size values are selected using the Score Accumulation Method. When the trapezoidal flow channel depth equals 0.5 mm and the flow channel and ridge widths are 0.9 mm, the fuel cell achieves the best operating performance. Besides, the rounding size optimization of the trapezoidal flow channel further improves the drainage and gas diffusion capacity by three times when the radius equals 0.1 mm and 0.2 mm. Additionally, this paper has identified the influence degree of the different flow channel structural dimensions on the fuel cell performance, which can be beneficial to future advancement and commercialization.

Gongjin Chen, Kai Luo
Research of Hybrid E-drive System Efficiency Influencing

Based on the development of a certain type of hybrid e-drive system for passenger cars, this paper analyzes the factors that affect the power loss of hybrid e-drive system, and systematically studied the efficiency influence of internal gear, bearing and lubricating oil on hybrid e-drive system in theory. According to the structural characteristics of the motor oil cooling mode in the hybrid e-drive system, the efficiency influence of the design of oil catcher and oil occupying on the system is analyzed. The CAE, bench test and vehicle verification show that the hybrid e-drive system based on oil catcher as well as oil occupying design is effective and energy-saving.

Xiao Tengfei, Lei Jun, Liu Huan, Ruan Xiane
Optimization of Installation Form of Battery Pack Based on Acoustic Sensitivity Analysis

The main content of this paper is to explain that the acoustic sensitivity of the trimmed body of the vehicle can be improved by optimizing the installation form of battery pack, and then the interior noise of the whole vehicle can be reduced. Firstly, based on the acoustic sensitivity theory and simulation analysis method, the analysis model of the trimmed body with battery pack structure is established, and the acoustic sensitivity of the key connection points of the trimmed body is simulated and analyzed. Secondly, the acoustic sensitivity of the trimmed body is effectively improved by optimizing the installation form of the battery pack and the structure of the battery pack bracket. Finally, the improved scheme is verified and tested on the real vehicle road, and the expected experimental results are obtained.

Yingying An, Chenglong Yu, Jianqiang Zhong, Mingjing Li, Jian Bao
Design of Speed Regulation Module for Automobile Air-Conditioning Blower

Due to the short-lived electric sparks of the brushed DC motors used in traditional automobile air-conditioning blowers, brushless DC blowers have been widely used in recent years, and commutation control algorithms are used in most speed control modules. However, the commutation control algorithm makes the motor torque fluctuate and the speed is unstable during operation, which eventually leads to unstable air volume. This article uses MC9S12XDP100 to design the speed control module of the DC brushless blower to improve its speed control performance. The speed control module uses the vector control double closed loop algorithm, and uses the expert system fuzzy PID in the outer speed loop for parameter tuning. The speed, air volume, and current tests prove that the speed control module solves the problem of unstable speed and air volume caused by torque fluctuation of the commutation control algorithm, and improves the speed control effect.

Houzhong Zhang, Lin Xu, Zicong Jia
Study on Car Body Solder Joint Failure Based on Crash Safety

Nowadays, hot forming steel plate is widely used in the main parts of automobile with the characteristic of high strength, high hardness, light weight, strong forming ability, small rebound and so on, and meet the requirements of automobile lightweight and crash safety. But the hot forming steel plane is a whole martensite structure whose physical metallurgical behavior in the process of resistance spot welding compared with ordinary high strength steel is larger, and softening and splashing of the heart affected zone may occur during welding. Due to the high strength of ultra-high strength steel materials, the mechanical properties of spot welding structure are also different with ordinary steel, we need to study the mechanical properties such as strength analysis. In the papers, providing a certain reference value for the subsequent development of models through the hot forming solder joint failure mechanism research, solder joint failure simulation verification, older joint failure simulation test structural optimization to improve the failure of hot solder joint, and real vehicle verification of the effectiveness of the optimization scheme.

Chen Cheng, Bengang Yi, Lizhong Mao, Hongsheng Tian
Research on Air Supply System Control of PEMFC Based on LQR Control

Proton exchange membrane fuel cell (PEMFC) is composed of several coupled components with complex nonlinear characteristics. Coordinating the work of each component and effectively controlling the air supply system are key measures to improve the efficiency of the system. In order to control the air supply system of PEMFC, this paper explores the influence of different input parameters on the energy consumption efficiency of the system, quantifies the relationship between the variables, and studies the change law of power consumption efficiency and peroxide ratio of the system. After that, separate feed-forward, feed-forward + feedback and LQR control algorithms are used to control the optimal peroxide ratio respectively, and the algorithms are verified by Matlab/Simulink simulation. The results show that the LQR algorithm has the best dynamic response speed, which is shortened by 17.0% and 47.1% compared with the feed-forward + feedback control and separate feed-forward control systems. At the same time, the maximum control error of LQR algorithm is the smallest, which is 52.6% and 84.6% lower than that of feed-forward + feedback control and separate feed-forward control.

Xiaohua Zeng, Meijie Song, Dafeng Song, Chaofan Niu
Dynamic Coordination Control Strategy of Dual-Planetary Power-Split Hydraulic Hybrid Vehicle

The ride comfort of driving has higher requirements for the double planetary row hybrid hydraulic hybrid system applied in the bus. However, compared with the electric hybrid system, the vibration problem of the hydraulic hybrid system is particularly prominent due to the different dynamic characteristics of the engine and the hydraulic pump/motor, as well as the structural characteristics of the multi clutch/brake system. In the process of driving mode switching and rear planetary transmission, the timing of state transition of power and executive part has a great influence on the output of the system torque, which leads to the impact of the whole vehicle. Firstly, considering the real-time response state of the power source and the driving demand torque analyzed by the driving operation, the “dynamic transition torque coordination control” function module is added to revise the demand torque for the second time, to solve the total output torque fluctuation caused by the change of control logic and torque distribution mode before and after the driving mode switching, so as to realize the system coordination control during the mode switching. Then, through the dynamic analysis of the rear planetary system, the approximate linear relationship between the system output torque and clutch/brake friction torque, pump/motor output torque is obtained, and the torque control law of pump/motor is obtained. At the same time, the coordination control logic between the power and the actuator in each stage is determined. Finally, the joint simulation results of Simulink and AMESim show that the ride comfort of the vehicle is greatly improved during the impact prone multi-mode switching and the upshift/downshift of the rear planetary row.

Xiaohua Zeng, Meijie Song, Ziliang Zhao, Xingjun Hu, Kehua Sun
Application of Composite PSO Algorithm in Hybrid Electric Vehicle Control Optimization

The optimization of hybrid electric vehicle control strategy parameters has always been the concern subject of researchers. At present, matching and optimization methods for the control strategy parameters are still being explored. The optimization of HEV control strategy parameters is a multivariate multi-objective nonlinear programming problem. Most of the methods adopted by OEMs are still based on large numbers of calibration tests and data analysis, through a large number of repeated modification of control parameters to obtain a relatively good data as the best result. As a result, the work efficiency is low, the research and the development cycle times are long. According to the characteristics of the PSO algorithm and its composite algorithm, it is not easy to fall into the local optimal solution, and the convergence speed is fast and the work efficiency is significantly improved. This paper provides a composite PSO algorithm for multi-variable nonlinear programming problems. The algorithm is easy to obtain better global optimization results. Combined with practical application requirements, it has been used to guide the development of actual vehicle control systems.

Fei Xu, Haibo Li, Yu Xie, Caiwei Sang
Low-Load Performance Analysis and Improvement Method of Automotive PEMFC System

Centrifugal compressors are widely used in automotive proton exchange membrane fuel cell (PEMFC) systems. Increasing the rotating speed of compressor could avoid surge under low-load conditions of PEMFC at the cost of reduced system net efficiency through increasing compressor power consumption accounting for more than 50% of the whole system. This paper proposes an Air-Bypass scheme to improve the efficiency of the PEMFC system under low-load conditions and employs a system model of a 60 kW PEMFC system with the GT-SUITE software. The influences of the Air-Bypass scheme on the operating point and power consumption of compressor, the oxygen excess ratio and the system net efficiency are analyzed. The results show that under the operation of ensuring a reasonable oxygen excess ratio under low-load conditions, the Air-Bypass scheme not only avoids compressor surge, but also reduces power consumption. In addition, Air-Bypass scheme makes the highest efficiency point of the PEMFC system reduced from 150 A to 50 A and the system efficiency of 20 A increased by 25%, which effectively improves the efficiency of PEMFC system under low-load conditions.

Xuanyu Wang, Kai Han, Xiaolong Li, Chang Ke, Bao Lv, Hongxia Tan, Zhaonian Ye
Research on the Influence of Voltage Platform on the Performance of Electric Drive System

As the main power source of new energy vehicles, the performance of electric drive system directly affects the power performance and economy of new energy vehicles. Aiming at the influence of voltage on the performance of electric drive system, the output torque, power and efficiency of electric drive system at rated voltage, high voltage and low voltage are studied respectively. Based on the bench test data of the electric drive system under different voltage platforms, this paper compares and analyzes the influence of voltage on the performance of the electric drive system, in order to provide a theoretical basis for the matching and selection of the electric drive system of new energy vehicles.

Wenhui Zhang, Zhao Song, Changhe Wei, Zhidong Qin, Jihong Liu, Ruzhi Qi
Risk Prediction of Power Battery Based on Logistic Regression Algorithm

Today, when we advocate the development of new energy vehicles, the improvement of battery management system is an important factor in the development of electric vehicles. Therefore, the estimation of the state of power batteries has become the key factor to ensure the safe driving of the vehicles. Traditional research on the low residual charge of power battery mostly uses the charge and discharge data of single battery under ideal experimental conditions, which may not be able to adapt to the real complex and changeable driving conditions and separate from the real driving environment. To solve this problem, this work relies on the national big data alliance of new energy vehicles and uses the data-driven method to build a time-varying, battery voltage, battery current and other angles to reflect the current working status of the remaining power (SOC) of the power battery. The type of power battery used in this paper is lithium iron phosphate battery, and the alarm group and prediction group are designed. The data of the alarm group are the collected power battery data detected as low residual power (SOC), and the data of the prediction group are the driving data of vehicles from May 9, 2019 to November 5, 2020. The logical regression algorithm is used to extract the battery characteristic information of low residual power, establish a model, and use the model to predict the data of the prediction group.

Yao-hua Li, Chao Ren, Xiao-yu Wang, Gui-xin Chen, Zi-kun Liu, Dong-mei Liu
Research on Consistent Separation Method of Lithium Ion Battery

Lithium ion batteries are widely used in electric vehicles because of their high energy density, small self discharge, long storage time, long cycle life and no capacity memory effect. The batteries in electric vehicles are composed of single batteries in series and parallel. However, due to certain differences in the performance of single batteries, the battery pack may have capacity failure and shortened service life. Therefore, it is of practical significance to quickly select the lithium-ion battery with the best performance for racing through a simple and reliable classification method. This paper analyzes the reasons for the differentiation of lithium-ion batteries, and verifies through experiments that it is reasonable to use the internal resistance and capacity of batteries for preliminary sorting.

Li Hongze, Hong Hanchi, Kong Qianxu, Shi Xu
Research on Driving Control Strategy of Electric Racing Car Based on Pattern Recognition

Aiming at the problem that the driver of the electric racing car cannot accurately select the driving mode during the competition, a driving mode recognition controller based on fuzzy control is first proposed, and three driving modes are divided by the interval of defining the driving mode factor. Then, for the power mode and the economic mode, 181 and 139 sets of data were drawn up, and the Adaptive Neuro-Fuzzy Inference System (ANFIS) was used to inferentially calculate the accelerator pedal opening correction coefficient, so as to realize the corrective control of the accelerator pedal. Finally, the effectiveness of the drive control strategy is verified by the joint simulation of VI-grade and Matlab/Simulink.

Li Yuxing, Hong Hanchi, D’Apolito Luigi, Ye Yangqi
Design of the Power System of a Formula Race Car with Dual Motors Driven Independently

According to the competition requirements of the Formula Student Electric China (FSEC), in order to improve the dynamics and economy of the car, it is necessary to match the parameters of the appropriate power system. This article is aimed at the design of the dual-motor independently driven formula racing power system. Match its motor parameters, battery parameters and transmission ratio, and determine the matching result preliminarily. Then, build a vehicle simulation model in Cruise and establish track conditions, analyze the dynamics and economy of the car, and the results show that the design parameters can meet the expected goals.

Yuran Ren, Gang Li, Qingdong Zeng
FSAE Aerodynamic Design Based on the Rear Layout of the Radiator and Targeted Improvement of the Cooling System

Taking the Formula Student racing car as the research object, and taking Jilin University Gspeed Formula Racing Team’s racing cars as examples, while using the new powertrain layout, a series of improvements are explored towards how to maximize the use of the engine cooling system with it being rear-mounted, to change the design ideas of the vehicle’s aerodynamics accordingly, and to optimize the aerodynamics of each part of the vehicle. The results show that in the case of the rear-mounted engine cooling system, the design ideas of aerodynamic devices are quite different from the ideas before the change. The aerodynamic devices designed under the new idea have significantly improved the overall performance of the vehicle, which results in a 4% improvement on standard lap time.

Da Wang, Fuqiu Zhou, Leqi Gu, Yuanxin Huang, Yuchen Shan, Mingjia Yang, Miaoxin Wang, Yuqi Zhang
Research on Matching Method of Traction Battery for Formula Student Electric Race Car

In the Formula Student Electric China (FSEC), the matching and design of the power battery directly affects the stability of the powertrain and the range of the race car. In this paper, based on the existing powertrain design, a matching method for the power battery for an FSEC race car is proposed. The key parameters of the power battery are calculated and matched using this method. At last, a simulation model of the race car was built using Simulink and CarSim, and it was used to evaluate the performance and range of the race car. The simulation results verified the feasibility and effectiveness of the proposed method.

Wuze Wang, Di Zhao, Tianqi Huang, Dazhong Xu, Hong Li, Tianzhu Jiang
Research on Brakeforce Distribution Strategy of Regenerative Braking System for a Four-Wheel Drive FSAE Race Car

In this paper, a brakeforce distribution strategy of regenerative braking system for a four-wheel drive FSAE electric formula race car is proposed based on the electric formula car of Jilin University. By reasonably distributing the electric braking force and mechanical braking force, the energy efficiency can be improved without degrading the dynamic performance of the race car. Finally, the feasibility and effectiveness of this strategy are verified by simulations using Simulink and CarSim.

Mingyuan Zhang, Di Zhao, Tianqi Huang, Ye Li, Hao Sun, Yanheng Xu
Improved Design of Hub Structure Based on Real Load Spectrum Analysis

The hub is an important part of the suspension structure of racing car. Under the high frequency and high amplitude acceleration, it is prone to fatigue failure due to alternating load, so it is very important to analyze its fatigue life. In this study, based on the real track conditions of the FSAE cars, suspension position sensor and vehicle acceleration sensor are used as the main inputs, combined with vertical load distribution between tires, the load spectrum at the hub is extracted. On this basis, the static analysis and fatigue life prediction of the hub structure are carried out, and the failure forms in the test are reproduced, then the structure of the parts is optimized. The improved design changes the fixed form of the brake disc and optimizes the load transmission path. The finite element analysis shows that the stress at the dangerous point of the new structure is reduced by nearly 50%, and the service life of more than 50000 km can be achieved, which meets the demand of long-time running on the track.

Yungujian Bai, Tianqi Qin, Zhaoyan Huang, Da Wang, Yi Sun
Research on Laster Positioning Algorithm of Unmanned Formula Racing Car

In order to solve the positioning problem of unmanned formula racing cars, a real-time positioning algorithm based on the combination of LiDAR and Inertial Measurement Unit (Inertial Measurement Unit, IMU) is proposed. Firstly, the high-frequency IMU data were used to compensate the motion distortion of the laser point cloud. Secondly, the feature points were divided according to the smoothness features, and the target optimization function was constructed according to the corresponding registration of different feature points to solve the laser odometer. Then, the Normal Distribution Transform (Normal Distribution Transform, NDT) was used to construct the loop constraint. Finally, the graph optimization algorithm is used to solve the real-time position and pose of the racing car and construct the environment map. In this paper, the performance test is carried out based on the data collected from the self-developed unmanned formula racing platform. The test results show that the real-time positioning algorithm proposed in this paper meets the positioning accuracy requirements of college students’ formula race, and can meet the real-time requirements in the actual scene application, which has a certain theoretical reference and engineering application value.

Xiaogang Li, Gang Li, Kai Zhang
Parameter Identification of Modified Bouc-Wen Model for MRF Damper Based on Genetic Algorithm and Nonlinear Least Square Method

In order to improve the adaptability of the suspension, we introduced the electromagnetic suspension, and the magnetorheological fluid has the advantages of fast response and large adjustable range. For the control of MRF damper, there is a problem of inaccurate modeling. The commonly used modeling methods mainly include Bouc-Wen model and hyperbolic tangent model, etc. However, the applicability of different omposition of MR fluid is poor, and the modified method has many identification parameters, which is difficult to identify. In this paper, a method combining genetic algorithm and nonlinear least square method is proposed, and the data of magnetorheological fluid damper are obtained through experiments, and the identification process and identification results are given. Through verification, it is concluded that this method can effectively identify the modified Bouc-Wen model.

Haoxiang Chen, Zexin Nie, Liangyao Yu
Research on Optimized Speed Limit Model to Improve the Cornering Ability of Intelligent Driving

This article analyzes the cornering control principle of the intelligent driving system in detail, and analyzes the input factors that affect its cornering performance. The results show that the system has different requirements for the desired cornering speed limit under different curve radius. Especially in the case of small radius with medium and low speed, the vehicle’s own driving feedback parameters and the same change of road curvature have weaker speed limit ability of the system, and there is also a strong hysteresis. Therefore, it is difficult to achieve a better speed limit effect by relying on the existing curve speed limit model.Based on the above analysis, this article proposes a method of “speed-curve radius” segmentation to establish an optimized curve speed limit model. During the SACC activation process, the system can automatically calculate the lateral acceleration using the curve radius detected by the camera, and extract the minimum target speed using the speed limit model. Subsequently, the ego vehicle calculates the longitudinal deceleration in real time according to the target speed, and sends a deceleration request for automatic deceleration. When the road curve radius is small, only ACC can be activated, and the detected curve radius cannot be used for stable speed limit control. At this time, the system mainly uses the speed limit model to predict the target speed limit value to ensure the deceleration ability of the ACC function in the longitudinal control. In addition, at certain speeds and curves, when the current model speed limit fails to make the corner smoothly, a test can be used to manually calibrate the lateral acceleration in advance, and the target speed limit value can be calculated by Model 3 to enforce the speed limit to ensure smooth cornering.

Pei Tao, Maoyuan Cui, Lianming Sun, Mingwei Tan, Junfeng Meng, Bin Liu
Research on Dynamic Scenario Predictive Description Algorithm of Automatic Driving

Intelligence is an inevitable trend of automobile technology and industry development, and its development pace is also accelerating. Autonomous driving has also become one of the research hotspots in the field of intelligent vehicles. Although there are many researches on autonomous driving, most of them are based on relatively simple scenarios. However, with the gradual expansion of the application scenario of autonomous driving, many scenarios present dynamic and complex characteristics, which makes the traditional path planning algorithm difficult to adapt. Therefore, the study of autonomous driving algorithm in dynamic and complex scenarios becomes the key to improve the adaptability of autonomous driving scenarios and promote the wide application of automatic driving. This paper proposes a dynamic obstacle tracking and prediction algorithm based on extended Kalman filter to reduce dynamic obstacle tracking. The tracking error caused by lag and its influence on trajectory planning. At the same time, a predictive description method of dynamic scenario is proposed. Based on approximate grid decomposition, hierarchical cost map updating method is adopted and the prediction cost layer of dynamic obstacles is integrated to complete the predictive description of dynamic scenario.

Fei Xie, Haiyang Huang, Jian Zhang, Yu Wang, Hongwei Jiang, SuTie Zhang
AEB Target Selection Method Based on Sensor Fusion

This paper proposes an AEB target selection method based on sensor fusion which includes three modules: perception-data-fusion, trajectory-prediction and AEB-target-filtering three modules. Perception-data-fusion includes three sub modules: time-space-synchronization, data-association and target-tracking. Trajectory-prediction includes three sub modules: signal-filtering, mode-selection and trajectory-generation. AEB-target-filtering includes five sub modules: coordinate-transformation, collision-judgment, collision-time-calculation, initial-target-selection and target-filter. This paper also designs an offline testing method and tool. The result of offline test aiming at typical AEB application scenarios shows that the proposed method has high accuracy and robustness which can adapt to different driving conditions.

Yingzhou Guan, Yinan Wang, Ying Lv
Continuous-Curvature Path Planner Based on RS Algorithm

Path planning algorithms directly affect the performance of the automatic parking assist system (APA). RS algorithm is very suitable for embedded code transplantation and can quickly generate the shortest parking path due to its low computational complexity, so it is widely used in the parking path planning algorithms. However, because the RS algorithm does not consider the constraint of curvature mutation, the phenomenon of turning the wheel on the spot often occurs during the actual parking process, which will not only accelerate tire wear, but also affect the driver’s driving experience. In order to solve the curvature instantaneous problem of the RS algorithm, this paper proposes a continuous curvature parking path planning algorithm, that is, to optimize and upgrade the RS algorithm with clothoid and straight line, and change the connection of arcs and straight lines used by the RS algorithm to clothoid arcs and straight lines, and so on the basis of retaining the advantages of RS algorithm, it can effectively solve the problem of curvature mutation problem during parking process. Finally, the effectiveness of the proposed algorithm is tested and verified by simulation and real vehicle experiments in two common parking scenarios. The experimental results show that the proposed algorithm is not only simple for embedded transplantation, but also can effectively solve the curvature mutation problem during parking process.

Chao Li, Jianyu Du, Jianfeng Li, YiNan Wang, Bin Liu, Ying Lv
A Survey of Driver Behavior Perception Methods for Human-Computer Hybrid Enhancement of Intelligent Driving

The subjective uncertainty of human-in-the-loop is a core issue for hybrid enhancement of human-computer shared driving that is the research hotspot of intelligent vehicle studies. Precise perception of driver behavior is a prerequisite and a significant method to break through the problem of human-in-the-loop uncertainties. Through literature comparison and analysis, we find that the objective evaluation method based on contact and non-contact sensors has received more attention from scholars in comparison with the subjective evaluation of driver behavior. However, there is no literature that addresses the new challenges of driver behavior perception under the condition of human-computer shared driving. Therefore the methods of driver behavior perception for hybrid enhancement of human-computer shared driving are summarized in this paper and the driver behavior perception based on visual and tactile multi-sensor fusion has been pointed out as the future research direction.

Jiwei Yi, Aimin Du, Zhongpan Zhu, Hongjun Ding
Research on Human-Imitative Autonomous Lane-Changing Method on Highways

As a common driving behavior on highways, lane changing has many effects on traffic flow. How to achieve safe, reasonable, and human-imitative autonomous lane-changing is a current research hotspot in the field of autonomous driving. Based on the driver’s lane-changing behavior data, this paper extracts lane-changing characteristic parameters reflecting the driver’s behavior, studies the human-imitative lane-changing trigger mechanism, uses polynomial curves to achieve lane-changing trajectory planning, and designs feedforward-feedback tracking controller based on preview theory. The simulation results show that this method can realize human-imitative lane change triggering, trajectory planning and good tracking control.

Weiguang Zhao, Zhenhai Gao, Zhu Zhang, Naixuan Zhu
Visual-Inertial Odometry Design Based on Nonlinear Optimization and Its Online Initialization Method for the Autonomous Navigation

There is a recognized complementarity between the vision system and the inertial measurement unit (IMU) in terms of autonomous navigation. Recently, visual inertial system (VINS) has become a hotspot of current research by fusing data of low-cost inertial measurement unit and vision system. However, the lack of direct measurement information makes the estimator’s initialization more difficult. This paper presents a method for online estimator initialization by using robust visual front end. One iterative process is employed to gradually align the vision system with inertial measurement unit. The convergence criterion can be used to determine the end of initialization, which can accurately recover parameters such as speed, scale, and gravity vector. This algorithm is applied to design a tightly coupled visual inertial odometry. In addition, experiments have been performed based on public data sets and equipment. The results show that the average absolute positioning error is less than 0.08 m, the relative positioning error is less than 0.03 m and the system has stable initialization performance with high accuracy positioning performance.

Yibing Zhao, Weiqi Wang, Yu Yang, Shuyong Xing, Bin Li
Application of SecOC Based on SM4 Algorithm for Communication Security of Bus in Vehicle

In order to promote the healthy and sustainable development of China’s Internet of Vehicles industry, the symmetric encryption algorithm generated by MAC is studied in this paper, according to the principle of SECOC secure communication mechanism in AUTOSAR specification. In this paper, based on the security framework of SECOC, the SM4 algorithm of the State Security is used to generate MAC, and MAC is added to the onboard communication in CAN to ensure the information security of the onboard CAN bus communication. Considering the high real-time requirement of vehicle network communication, the application scheme was verified by experiments.

Peng He, Lei Gao, XiaoJuan Huang, Chunyi Zhou, Guangyu Tang
Research and Application of Real-Time Measurement Method of Engine Oil Consumption

This article studies and exposes the measurement accuracy and consistency problems of the traditional oil consumption weighing method, plans to conduct multi-sample, strong-constrained user tests, and determines the engine oil consumption benchmark values through the accumulated oil consumption data and multiple samples. At the same time, research and compare the accuracy and measurement influencing factors of the existing two-principle oil consumption real-time measurement device, optimize the equipment, optimize the boundary of the test system, and study the online data processing method and output form to balance the test duration and measurement accuracy. Finally obtain a combination of test equipment and methods with high engineering application value. It is also used in the monitoring of engine oil consumption and the prevention of malfunctions in the laboratory endurance test.

Zhiyong Liu, Xiao Li, Zhijun Zhao, Weijian Zhu, Zhengxin Xu, Yue Wang, Lin Zhang
Theoretical Analysis and Engineering Design of Spiral Groove Hydrodynamics Thrust Bearing for Turbocharger Application

This paper raise a spiral groove thrust bearing structure for turbocharger application. The related theoretical thermal hydrodynamic analysis process is presented, which is applicable for any complex thrust bearing geometry for turbocharger application, and important knowledge in real engineering design of such bearings is pointed out in this paper. Finite difference method is used for solution of energy equation and prediction of temperature distribution. And finite volume method is adopted to solve the Reynolds equation to find hydrodynamic pressure of the bearing. Calculated lubricant flow is assumed to carry away all the heat generated by shearing of the lubricant, and an iteration scheme is employed to converge on the mean lubricant temperature. The calculation method established in this paper is validated by experimental data, and then related structure optimization on spiral groove thrust bearing is illustrated. Finally several critical engineering design knowledge are also pointed out and their influences on bearing performance and life discussed. These include oil carry over, minimal oil supply, oil dilution, shearing shinning, and erosion by oil cavitation, bearing pad ramp or groove depth tolerance sitting and surface roughness.

Gao Lei, Niu Pengfei, Zhang Zeyu
Experimental Research of 500 bar Ultra-high-pressure Fuel Injection System for Gasoline Direct Injection Engine

The characteristics of 500 bar ultra-high-pressure fuel injection system was studied on a 1.5 L gasoline direct injection (GDI) engine, the comparison of gaseous and particulate emissions and fuel consumption under cooled and hot engine conditions was analyzed between 350 bar and 500 bar of injection pressure, including part load, full load, and mini map points that have been extracted from world light-duty test cycle (WLTC). The results show that, the benefit of particulate decease from 500 bar will be achieved at different conditions, which could reach roughly up to 50% at part load while 30% for average at full load. Moreover, both of the nucleate and accumulative particulates show obvious improvement at all the sizes range, which will provide effective solution for meeting the challenge of particulate limit with smaller size from more stringent legislations. On the other hand, the ultra-high-pressure fuel injection almost would not produce negative effect on fuel consumption and gas emission under most conditions.

Yajun Zhang, Chuanhui Cheng, Zheng Xu
Structural Optimization Design of BIW in Concept Stage

In concept development stage of traditional body development process, simulation and optimization could not be done with no geometric data. In this paper, a parameterized model was built based on the reference car parameterized model, new car style and section data. The parameterized model was used to analyze the influence of modeling on the performance of vehicle body. Multi-disciplinary and multi-object optimization was carried out based on stiffness, collision and mode. An approximate model was constructed by response surface method. Section size was optimized to improve the structure performance and thickness of the body parts was optimized to reduce weight. At the concept stage, the performance reached the standard and the weight was reduced by 16.7 kg.

Hongjun He, Baojun Yu, Liwei Sun, Ning Wang, Xuewu Zhu
Analysis of Dynamic Mechanical Behavior of Hot Formed Steel

The tensile tests of hot formed steels with strength grades of 1500, 1800 and 2000 MPa at strain rates of 0.001~500 S−1 were carried out by using electronic universal testing machine and Zwick high speed tensile testing machine respectively. The strength indexes of three experimental steels, the plastic elongation strength Rp0.2 and the tensile strength Rm are quantitatively analyzed in combination with dynamic factors. The results show that the strain rate sensitivity of the three experimental steels decreases with the increase of material strength grade. The strain rate sensitivity of RP0.2 of the three experimental steels is higher than that of Rm. Both RP0.2 and Rm of the 1500 MPa test steel show obvious strain rate sensitivity, and the strain rate sensitivity is the highest in the strain rate range from 100 to 500 s−1. Rm of the 1800 MPa test steel and RP0.2 and Rm of the 2000 MPa test steel have no obvious strain rate sensitivity, indicating that with the increase of material strength grade, the softening effect caused by the adiabatic temperature rise gradually counteracts the strain rate strengthening effect. The plasticity index of the test steel after fracture shows obvious strain rate sensitivity at strain rates from 1 to 500 s−1, mainly due to the obvious effect of adiabatic temperature rise. The phenomenon of adiabatic temperature rise cannot be ignored at high strain rates.

Guangxiang Cao, Jun Li, Qifeng Song, Xiaofei Dong, Jian Song
Design of Brake Disc Dust Cover Based on Multidisciplinary Optimization Method

Modal, stiffness, vibration durability and other multidisciplinary properties need to be considered in the structural design of brake disc dust cover. An optimization process was created, including the conceptual design and detailed design process to ensure that the multi-disciplinary objectives were achieved. In the conceptual design process, through the joint optimization of topology and topography, the objectives of modal and stiffness can be achieved, which ensures the structural reinforcement and the location of the holes were optimal. In the detailed design process, the height of the flange, the height of the convexity, the width of the holes, and the thickness of the sheet metal were parameterized, and a multidisciplinary optimization process was constructed. This is a new design idea for multi-disciplinary optimization of the brake disc dust cover.

Qiao Yan, Wu XiaoLong, Shi ChaoLiang, Shen Sheng, Wang Lou, Gong Shuai
Comparative Analysis of Estimation Methods of Control Limits for the Engine Cold Test Parameters

The design of control limits of the parameters in the engine cold test is quite important to ensure the quality of the engine manufacturing process. In the present study, characteristics of three estimation methods including the moment estimation, the median-range estimation and the Gaussian score estimation for different parameters were analyzed based on the signal value characteristics of parameters in the engine cold test. Performance of each method to estimate the control limits of parameters in the engine cold test was studied. Reliabilities of the estimation methods were verified by expanding the sample size and the signal sampling range. The result shows that a reasonable parameter estimation method can eliminate effectively sample errors and obtain more reliable control limits under the conditions that the sample size is limited or there exists extreme data in the sample. This study can provide a solid support for the engine production.

Fan Dong, Hong Zhang, Zeguo Du, Chang Han, Xiaoyu Yang
Opening Draw and Die Design of Rear Fender

After a few decades of rapid development and growth, China has become a major country in automobile manufacturing and sales. The domestic automobile market has firmly established itself as the world’s number one automobile market. Cars have gradually transitioned from incremental competition to inventory competition. With the intensified market competition, customers have increasingly higher requirements for the overall perceived quality of car seating space and appearance. In order to meet market demand and improve product competitiveness, all manufacturers are working hard to reduce manufacturing costs and improve product quality. In order to meet customers’ requirements for high cost performance of cars, and to improve the utilization rate of parts and materials, it is an effective means to reduce the cost of car manufacturing.

Li Wei, Xie Yonggang, Ye Changlin
Research and Application of Process Appraisement Method in General Assembly Field

In the process of automobile design and development and assembly production, process appraisement plays an important role. This paper studies the process appraisement method from the concept, work content, standard process and review elements of process appraisement, systematically expounds the objectives and significance of process appraisement, and proposes accurate and effective evaluation methods for the current situation of the industry in the field of general assembly, forms the General Assembly review specification, and demonstrates the role of digital technology in the process of process appraisement through application examples, open up new ideas of process appraisement, and point out the application process and effect of the evaluation method.

Jieshi Yan, Liguo Cong, Lianhui Feng, Chuanyu Zhang
Application of Virtual Process Verification in Production Preparation of Instrument Panel Assembly Line

Virtual process verification is an important part of vehicle development, which plays a connecting role between product development and actual vehicle assembly process. Standardized assembly process verification can detect and avoid defects generating fundamentally during the product design and development stage. Through improving and optimizing the design scheme to eliminate the detected defects, the manufacturing costs can be effectively reduced and also the production preparation cycle can be shortened. Taking the introduction of new instrument panel of a new platform model in an original equipment manufacturer (OEM) as an implementation case, this paper illustrates the utilization of virtual process verification in the product design stage from the aspects of assembly process, man-hour balance, logistics planning, workshop layout etc. Based on the application of virtual simulation technology, the process preparation for mixed model production of new type instrument panel is completed with the minimum cost and the shortest cycle, which significantly ensures the successful production of new vehicle project.

Ye Qin
Research on Lightweight Composite Bulletproof Technology of a Protective Vehicle

Under the influence of the new military strategy and the revolution of military technology, a large number of new technical weapons are used in the battlefield. With the sudden increase of modern war, the impact, mobility and firepower of weapons and equipment are greatly enhanced, which leads to a greatly increased war damage rate of equipment. Therefore, the protection ability of weapons and equipment has been paid more and more attention by all countries. Military vehicle equipment is the main land mobile platform in the world, and it is also one of the most numerous and widely used equipment. In this paper, a kind of bulletproof performance scheme of light tactical vehicle is put forward. The main purpose is to use the combination scheme of bulletproof steel plate and aramid fiber composite material to analyze and optimize the bulletproof performance of bulletproof plate by combining CAE simulation analysis and test verification, so as to ensure its bulletproof performance and greatly reduce its weight.

Li Yilun, Zhang Luyang, Zhu Jijin, Zhang Weichao, Hu Wenhai, Han Fei, Li Qing, Zhang Min
Effect of Graphene Content on the Mechanical Properties of PMMA Composites

The effect of graphene reinforcement on tensile strength, elastic modulus and fracture toughness of the graphene-PMMA composites was investigated. Graphene-PMMA composites were prepared with 0.5, 1, and 3 wt% graphene incorporated. It was found that the graphene flakes were self-oriented to the horizontal direction. The untreated graphene was found has little effect on the tensile strength of the composites, but the fracture toughness was improved by 40–50% with 0.5–1% graphene incorporated. Examination of the fracture surfaces of the samples after tearing tests found that the graphene made the cracks deflection and branching happen during crack propagation, which increased the energy consumed for fracture of the composites. Tensile tests with single edge notched samples were also performed, the observation at the notch tip found the plastic deformation zone formation around the notch tip on the samples with graphene incorporated, while the pure PMMA samples all had brittle fracture.

Sun Guanhong
Dedicated Hybrid Engine Main Bearing Ticking Test Study and Root Cause Analysis

Powertrain electrification brings new challenges to strange noises due to new engine operational applications [1–3].Unacceptable noises may have negative influence on the marketability [4]. Therefore, sound quality development instead of sound pressure level are the basic features of OEM products to improve [5–7].On one hybrid 3-cylinder engine, crankshaft main bearing strong ticking was detected on engine test bench as well as that on vehicle during idle charging. This error state occurs under P gear tip in and idle charging which led to big complaints from customers. By simulation and bench testing the root cause was identified as the third main bearing oil cavitation collapse. Upon this finding a new lubrication concept of the crankshaft bearing and connecting rod bearing were developed.This paper explores the causes and countermeasures.

Hao Wang, Ping Luo, Wenqiang Liu, Zhirong Geng, Junfeng Hu, Feng Guo, Sichao Zhang, Qian Wang, Guiqiang Zhang
Research and Application of Vehicle Dynamic Interference Method

Body dynamic interference is one of the common phenomena in the process of vehicle road tests. It is easy to cause sensitive and disgusting problems such as knock off paint, friction deformation, noise and so on. Based on the principle of direct method, this paper studies the theory of multi degree of freedom forced vibration, the algorithm and process of time-domain transient response analysis, and puts forward a dynamic interference method for vehicle body, which adopts the self-developed DIA (dynamic interference) method. The load input, modeling analysis, diagnosis and optimization of the system are carried out, and the system is applied to the trunk lid system to identify and optimize the problem more accurately. This method can be extended to the prediction of dynamic interference among vehicle, subsystem and parts.

Junjie Duan, Jieliang Zhou, Wei Chen, Xiaohuan Wu, Chengzhi Sun, Guangyao Wang, Zhenliang Lou
Gear Whine Optimization of Hybrid Transmission Based on Dynamic Excitation

This paper takes gear order whine in electric drive mode of hybrid transmission as research object. Based on gear static transmission error, considering the influence of speed excitation, shafting frequency and housing flexibility, the paper analyzes bearing dynamic reaction and vibration velocity of transmission. By optimizing shafting and housing layout to decrease bearing dynamic supporting force, the gear whine noise can be reduced obviously, this research has good guiding significance for development of gearbox.

Pin Lv, Meng Zhang, Tianbao Tang, Xiaolong Deng, Junfeng Hu, Jun Lan
Influence of Foaming Process on Acoustic Performance of a Vehicle with a Typical Lightweight Floor Carpet

This article focuses on the effect of different foaming process on acoustic performance of a vehicle with a typical vehicle lightweight floor carpet. The carpet structure difference between 2 different foaming processes was discussed firstly. A statistical energy analysis (SEA) based transmission loss model was developed to predict the sound transmission loss (STL) under different boundary conditions. It was found that the STL of the carpet with direct foaming process is much worse than the separate foaming process carpet when the boundary condition was Bonded-Bonded. Then a full vehicle SEA model was developed to predict the sound pressure level (SPL) at the front-left (FL) driver’s headspace. In parallel, a test was conducted to measure the SPL response at the same space after the floor was assembled on the vehicle. The test results showed the good agreement with the simulation results.

Yi Huang, Yuqing Ge, Weiqiang Liang, Lin Liu, Ding Li
Diagnostic Analysis and Improvement of a Chinese VI Engine with Abnormal Noise in EGR System

The abnormal noise on the exhaust side of a Chinese VI engine under low load condition was diagnosed by the engine acoustic testing technology in the paper. Based on the theoretical analysis that the non-uniformity of air flow field could produce high-frequency vortex noise, the structural optimization design and computational fluid dynamics simulation of EGR system were carried out to improve the flow field uniformity in EGR bellows. The retest results showed that the abnormal noise at the exhaust side was eliminated, which provided a reference for the diagnosis and improvement of engine components with abnormal noise.

Chenghui Xu, Zhengyu Tan, Leilei Chen, Fengxia Ou Yang
Study on Optimization of Heaviness of Door Closing Sound

The optimization was taken on front assembly door to improve the heaviness of closing sound quality. First, by using the single variable control method, we found out the contribution of main seal, second seal and door lock on the heavienss. Then by measuring the sound pressure level and striker reaction force of lock during door closing on test simulate bench, we found out the peak value of SPL and reaction force happened when latch respectively impact with stop block and pawl. Finally, we designed an orthogonality test to optimize the stop block and pawl by adding buffer structure. Test result showed that door closing sound quality solid feeling was improved 11% with the most optimal parameter.

Jianhua Zhu, Liwen Lv, Yuande Liu, Hao Hu
Study on Accelerating Boom Control of a Certain SUV

This paper mainly discusses the control method of accelerating roar of a certain SUV. Aiming at the problem of roar during vehicle acceleration in actual vehicle development, the mechanism of roar is analysed. Through the test, it is confirmed that the front subframe is the part which contribute a lot to acceleration roar, after optimizing the sheep horn of front subframe, the dynamic stiffness of the attachment point of rear engine mount can be improved. Finally, the test results show that the optimization scheme has obvious effect and effectively solves the problem of accelerating roar of the vehicle when the engine is 3750 rpm.

Gong Yipeng, Su Ruiqiang, Shi Jiaohua, Zou Yan
Simulation and Optimization of Vehicle Booming Noise Based on DFSS Method

In the past, the problem of vehicle booming noise is exposed in the real vehicle stage, when most of the related parts are locked, so it is difficult to change any design. Only by adding damper and other patching measures can be taken to solve the problem. In this paper, the optimization research of booming noise is introduced, by means of CAE and DFSS tools in the early design stage of the vehicle. Through the analysis of transfer path, it is found that the path that contributes the most noise comes from the path “power train-tie bar mount-sub frame-vehicle body”. The CAE model is established to predict the vehicle interior noise. The sensitivity of parameters of the tie bar path is studied in detail and optimized design is carried out by using DFSS tool. The simulation results show that the maximum second order booming noise of the vehicle is reduced by 3 dB after optimization. The analysis method and results are validated by test.

Lu Bocong, Xu Zheng, Chen Ming, Wang Yanjun, Zhang Xiaohu, Shi Zhinan, Liu Xuelai
Research and Analysis on Knocking Noise of Mechanical Vacuum Pump of Turbocharged Direct Injection Engine

In the present paper, the knocking noise of a mechanical vacuum pump of turbocharged direct injection engine is researched. By noise, vibration, phase and air pressure signal during operation of engine, wavelet transform and angle domain analysis method are applied to identify the source of the knocking noise, determine the contribution of exhaust valve plate material, shape and stroke, etc. to the knocking noise. And the intensity of the knocking noise at idle speed is lowered by the methods of replacing material, changing shape and lowering stroke, etc. Based on this, the scheme of adding pressure stabilizing cavity on the back of the exhaust valve plate is finally determined by combining with reliability and cost to effective control the knocking noise of the mechanical vacuum pump. The present paper provides design suggestions and references for during design of engine mechanical vacuum pump, and it has certain guiding significance for avoiding knocking noise caused by design defects of mechanical vacuum pump.

Gu Qingwei, Yang Jincai, Zhang Yao, Li Xiang, Hu Gang, Wei Zehong, Luo Le
Multi-disciplinary Design Optimization of Vehicle Performance Based on Design of Experimental and Approximate Model

In order to solve the conflict problem between front suspensions flutter and idle vibration which caused by mount parameters. Parameter graph analysis and simulation integration were conducted, an approximate model was built using DOE method, on which a simulation was conducted to fulfill the optimization design of multiple performances, finally, front suspensions flutter and idle vibration were balanced by considering coupling relation.

Su Yonglei, Zhang Weineng, Li XueLiang
Design Modification of Vehicle Body Structure for Wiper System Waterproof Performance

Taking the wiper system of a vehicle as the research object, the overall waterproof performance of the wiper system is evaluated. Using the CFD simulation software PreonLab to simulate the water flow under the condition of car washing, and the waterproof failure state of the wiper system is reproduced. Combined with the simulation analysis and vehicle experiment, the drainage effect of the vehicle air box is improved, the depth of the water in the air box is reduced, and the waterproof performance of the wiper system is guaranteed. The water flow simulation analysis of PreonLab can well support the waterproof performance design of wiper system.

Jianrong Yan, Kongying Zhu, Xiaolong Huang, Kaihang Chen
Optimization of the Matching Performance of an Electric Vehicle’s Vacuum Source

Taking the change of vehicle’s vacuum pressure and brake pedal force under certain test conditions as the research object, a test and evaluation method for the matching performance of the vehicle vacuum source is established. For the poor matching performance of an electric vehicle’s vacuum source, the optimization scheme is proposed. According to the theory of fluid mechanics and vacuum design, the dynamic vacuum pressure’s simulation model is established. The simulation results show that the optimization scheme is feasible. Finally, the experimental results show that the matching performance of the electric vehicle’s vacuum source is obviously improved after adopting the optimization scheme.

Sijie Niu, Gang Peng, Peng Zhang, Yandan Zheng, Yi Li
Analysis of the Influence of Hinge Inclination on the Self Closing Force of the Door

The door closing force is one of the important factors affecting the quality of the door switch. The appropriate door closing force can help the passenger close the door easily and get a good driving experience. By combining theoretical derivation with real vehicle data, this paper summarizes the influence trend of hinge inclination layout range and heavy torque on door closing force, and then a software is developed to quickly calculate the door’s heavy moment curve, which provides a convenient optimization method for the layout of automobile hinge inclination.

Jing Chen, Yonghui Meng, Xiaoqiang Tong, Feng Xue, Jingru Bao, Junping Qiao
The Research on the Subjective and Objective Drivability Evaluation and Analysis of PHEV Passenger Car

In view of the influence of PHEV’s complicated control strategy and operation mode on driving performance, the subjective and objective evaluation testing are conducted on a PHEV passenger vehicle with a DCT powertrain combination of three-cylinder machine and built-in motor. The results show that in the operation of switching between hybrid and pure electric modes there are much more disadvantages to the drivability evaluation, including engine start and stop, automatic transmission shift, as well as engine and motor speed torque variation. The longitudinal acceleration of the studied vehicle does not fluctuate greatly during the mode switching process, which indicates that the drivability calibration was being performed to get the optimized data in the development. The transmission of the studied vehicle has obvious shift shock, but the shift response, engine start-stop performance and vehicle comfort score are higher. In the starting condition and acceleration process, the motor has fast response, small vibration and good subjective feeling, which reflects the unique configuration advantages of PHEV in driving performance.

Jianjun Yang, Wencui Guo, Xianfeng Zhang
Research on Crash Simulation Technology of Carbon Fibre Reinforced Plastic Vehicle Body

Carbon Fiber Reinforced Plastics (CFRP) have the advantages of low density, high strength, corrosion resistance, etc. With the improvement of CFRP manufacturing and processing technology, CFRP have been increasingly used in the automotive industry. In this paper, based on a vehicle model with CFRP body structure, the research of multi condition vehicle crash safety simulation technology is carried out. First, study the CFRP vehicle modelling method. Then, calibrate the constitutive of CFRP and structural glue, obtained characteristics parameter through a series of sample-level and component-level tests and simulation. Finally, the CFRP vehicle body crash simulation method was calibrated and revised based on static pressure of roof, frontal impact test and rear impact test. On this basis, a systematic crash simulation method of carbon fiber vehicle is established, which ensures the high consistency between simulation results and vehicle level test, and has guiding significance for carbon fiber vehicle body design.

Xuewu Zhu, Zhou Yao, Shibin Wang, Longbo Ji, Fangming Lou
Investigation on Energy Transmission of the MPDB

Reasonable structure design is the fundamental way to reduce the compatibility penalty points in the MPDB occasion and the energy absorption of the vehicle is the first condition to be satisfied for the structure design. In this paper, the structure feature of the barrier in MPDB and the crash strength versus deformation curve of energy absorbing material (honeycomb aluminum) are investigated. A calculation method of the energy absorption of the barrier is proposed combining the deformation of the barrier after collision. Then, the energy absorption target of the vehicle is determined and the transfer process of the energy between the vehicle and the MPDB is clarified. Further more, based on experimental data, the residual kinetic energy of MPDB, the residual kinetic energy of vehicle, the energy absorption of the barrier and the energy absorption of the vehicle in the process of the collision are estimated. Meanwhile, the comparisons of the differences of the above mentioned energies which are caused by the differences of the vehicle weight are done. The theoretic and data supports are afforded for the designing and optimizing of the vehicle structure by the energy transmission analysis of the MPDB occasion.

Xiaojie Chen, Dong Zeng, Yani Cai, Kecheng Huang, Jiabin Zhong
Parametric Study on SUV-e-Bike Collision for Safety Test & Evaluation Regulations

To explore the kinematics and injury response of the rider’s head after the collision with the vehicle, and to determine the test and evaluation boundary for its protection. An accident involving an e-bike was reconstructed based on an automatic operation framework, then the reliability of the reconstruction model was verified from comparisons of rider’s kinematics, the rest position of three participants, and injury with accident information. Furthermore, a total of 1296 parametric cases were performed by the automatic operation framework, which was based on the validated model with a full factorial experimental design according to the collision boundary such as velocity, position, and angle from accidents. Finally, a data set with 1005 valid cases were used to discuss the distribution patterns of the head’s kinematics and injury response when colliding with the vehicle such as initial impacting time, linear and angular velocity, WAD, and also for head injury criteria (HIC15). The results show that WAD is positively correlated with the size of the rider and vehicle speed. All head contact points on the vehicle are located before WAD2100, and WAD1100–1600 should be considered significant for riders’ protection. 92% of the head impacting linear velocity are lower than 50 km/ h,78% is less than 40 km/h. Head collision angle of 50–70° accounts for 62%, and the average angle of 5th,50th,95th are 57°, 61°, 62° respectively. Head subsystem impactor, within test area of WAD1000–2100 and with impacting velocity of 40 km/h and angle of 65° in current pedestrian protection regulation, seems to be applicable to the boundary of test and evaluation for SUV to e-bike riders. 82% of cases with head initial collision time are less than 140ms, and head injuries of e-bike riders mainly come from ground collisions. As a preliminary exploration, distribution patterns of rider’s kinematics and injury response in this article will provide data and theoretical support for formulation and revision of evaluation regulations and also for the development of safety performance when considering e-bike rider’s protection.

Yu Liu, Xinming Wan, Wei Xu, Liangliang Shi, Zhonghao Bai
Study of the Response of the Front-Row Far Side Dummy Under Vehicle Side Impact Condition

The text is based on the AE-MDB side impact condition of a certain SUV model. Aiming at two 50th male dummies, ES-II and WorldSID50, the CAE simulation analysis method is used to study the difference in the motion posture and injury value of this two dummy. The research results show that due to the difference in the quality and size of the dummy, the motion posture of the head and pelvis of the far side dummy is different. Among them, the head and upper torso of the ES-II dummy move faster. Comparing the performance of the damage value, the head and pelvis damage value of the two types of dummy are higher. The above conclusions provide references for the far side occupant protection of the vehicle side impact.

Zixiao Chen, Yanhao Wang, Wanli Li, Gaojun Chen, Chengjing Zhou
China’s Automobile Recall System and Recall Implementation Status

The recall of defective automobile products is an important part of the recall of defective products in China. The “Provisions on the Administration of Recall of Defective Auto Products”, which established and implemented in 2004, officially opening the prelude of China’s defective product recall. From the implementation of the automobile recall system in 2004 to December 31, 2019, China has implemented 1,992 defective car recalls in 15 years, with a total of 75,780,128 vehicles recalled. Based on the public information, this paper expounds the development of China’s defective automobile recall system, makes accurate statistical analysis on the long-term data from 2004 to 2019 and the short-term data from 2015 to 2019, so as to put forward suggestions for the quality management of the automobile industry and the improvement of the recall system.

Yiming Bai
Research on the Establishment and Application of Demand Value Analysis Model for Automobile Products

An innovative method of value analysis of automobile product demand is proposed which includes two sub models: creative demand value and commercial value analysis. The creative demand analysis model can be employed to analyze the various demands in the early stage that the customers have no experiences. After the prototype samples or advanced technologies are developed according to screening high value demand, the customer can be organized to experience this, and then commercial value analysis model is used to make commercial investment decisions. This method improves the limitation of Kano model analysis, which can be used and popularized as a demand decision analysis tool in the product development of enterprises. The demand analysis method is carried out with practical cases, which can improve the decision efficiency and quality in the early stage of automobile product development, shorten the development cycle and reduce the development cost.

Yu Xiong, Heng Yuan, Wensheng Zeng, Junwu Zhou
User Behavior Optimization Strategy for Electric Vehicle Based on Improving Battery SOH

Rapid decline of the battery SOH is one of key bottlenecks hindering further promotion and application of new energy vehicles (NEVs) in China. In order to improve battery SOH, this study focuses on electric passenger vehicle as the research object and proposes optimization strategies on the vehicle user behaviors. First, we calculate and compare the monthly average SOH decline level of on-board power batteries made of lithium nickel cobalt manganese oxide (NCM) and lithium iron phosphate (LFP) cathode materials based on the big data of 525 electric passenger vehicles that operated for one year from the platform of Shanghai EVData. Second, we analyse the main factors affecting SOH. Combined with the investigations, 14 indicators of vehicle use behaviors, such as the average vehicle speed and charging depth, which affect the SOH of power battery, are determined as input variables, and the prediction model of battery SOH is established based on Back propagation (BP) neural network. Third, we use the two-step clustering method to divide user behaviors into two categories, namely the private car mode and the online car-hailing mode. Finally, we propose optimization strategies on user behaviors for different battery types of vehicles respectively, followed by confirming the results via deploying the SOH prediction model. The results show that the proposed strategy is efficient on improving the SOH of the two cathode materials-based batteries under three scenarios, while their degree of improvement is different.

Xiaoyuan Wu, Zhelun Zuo, Pengyu Liu
Research on Software Project Configuration Management Based on Iterative Development

Standing at the forefront of the “software-defined car” era, intelligent network connection has become the focus of automotive software development. In the process of research and development of automotive software, we are faced with the dilemma of frequent changes in requirements and rapid update of design and testing methods. In order to improve the quality of research and development of automotive software, embedded software generally adopts an iterative development model. How to solve the problems of frequent update of requirements and frequent design changes requires a powerful software project configuration management method. This article proposes a software project configuration management method based on iterative development; combining the requirements of Automobile SPICE, the configuration management layout and construction work of software projects are carried out from five aspects: project status, configuration management strategy, project baseline, configuration audit and research results.Through one-year project practice, this method not only significantly improves the research and development efficiency of software projects, but also provides more efficient research ideas for the quality of automotive software, and achieves the research goals.

Yun-lin Ma, Yi Gang, Dong-ping He, Xiu-quan Tan
The Construction and Applications of Visual Management Model for Automobile Body Project Management URD

Facing the rapid development of the market, the project management of automobile products must adapt to the changes of the external environment, adjust the internal project management mode, change the management concept to meet the needs of the market development. In addition, a new management mode is needed to reduce the management cost and improve the management quality. Automobile body project management is an important link in automobile project development. This paper introduces the concept of URD (Unit Of Research & Development), which is a visualizing project management model, according to the six dimensions of mission and process, target results and performance, standards, capabilities, problems and risk handling, and work promotion, using visual management checklists and symbols, colors and other media for management promotion. The purpose of the construction of this model is to improve the quality and efficiency of body project management through the key control of the six elements of project quality, cost, time, risk, goal and communication.

Yan Wan, Jianyang Lin, Chi Dai, Rui Li, Jianzhu Yang, Xueyuan Yang, Hui Wang
Development Status and Proposals for Insurance Industry of Intelligent Connected Vehicles

This article conducts research on insurance industry of ICV (Intelligent Connected Vehicles), analyzes present issues including liability division, insurance clauses, insurance products based on current domestic and overseas development status of ICV insurance industry. Provide development proposals relating to laws and regulations, compulsory traffic insurance, protection principles and industry cooperation.

Xiao-long Li, Ming-lang Li, Ze-zhong Zhang, Gui-hua Chen, Ning Sun
Analysis and Research on Pitting Failure of a Passenger Car’s Hybrid Transmission Gear

Aiming at the problem of pitting on the tooth surface during the development of a hybrid transmission for a passenger car, this paper analyzes and studies the failure causes of pitting on the tooth surface through the theoretical analysis of gear strength, gear misalignment analysis, and tooth surface contact stress analysis. Then, based on the parametric analysis method, the gear micro-modification parameters are further optimized, and the new micro-modification parameters can satisfy the balance between gear durability and NVH performance. Finally, the gear micro-modification parameters design was verified through the endurance bench test and NVH bench test. The gear tooth surface pitting analysis method and gear micro-modification design method described in this article provide a guidance for gear design.

Huan Liu, Jun Lei, Long Xue, Xian’e Ruan, Tengfei Xiao
EMC Analysis of High and Low Voltage Wiring Spacing for New Energy Vehicles

With the gradual improvement of vehicle electrification level, the layout and wiring of electrical parts are facing unprecedented challenges. EMC performance becomes a key performance indicator after the continuous compression of the spacing between electrical parts. Especially for new energy vehicles, there are both high and low voltage systems. If the high and low voltage coupling is not handled well, EMC problems will occur frequently. This paper focuses on the EMC analysis of the high and low voltage wiring spacing of new energy vehicles, and makes a comprehensive analysis from the aspects of theory, standard, simulation and test, and gives relevant wiring spacing suggestions.

Hongwu Wang
The Study of Re-construction to Implement SOA on T-Box Based on SOME/IP

By giving perspective of current Telematics Box (T-Box) software architecture, stating traditional vehicle Electronic Control Unit (ECU) with closed system faces be given up immediately this embarrassed situation, study gives re-construction T-Box solution. This new solution will integrate vsomeipd & CommonAPI components, deploys the Service Oriented Architecture (SOA) vehicle application on T-Box, opening T-Box vehicle Application Program Interface (API) and so on. Examination verifies the implementation of new solution that is based on Scalable service Oriented MiddlewarE over IP (SOME/IP) protocol truly, and makes consuming time statistic analysis of invoking method fun0 (test sample) on 4 kinds of network medias, table data also shows this T-Box application has high performance and perfect user experience. The re-construction solution achieves the paper study goal.

Baohua Xia, Guoping Qian, Xibin Wu, Zhenghua Lu, Mengyong Hu, Fusheng Tan, Jia Li
Research on Boost Control Method for Turbocharged Gasoline Engine

Due to the nonlinear characteristic of turbocharger and engine operation conditions changing rapidly, the overall theory of boost control is put forward, low speed acceleration capability based on torque request and current engine combustion torque possibility is improved, the algorithm of ‘feed forward + PID + I item self-adapting’ is decided. Eventually, boost control response accuracy and torque control precision. The result shows that the behaviors of boost pressure control and torque response can meet engine dynamic performance.

Long Qin, Kai Wang, Fengmin Tian, Xue Lei, Liuchun Yang, Tianfang Zhao, Yanyan Lei, Zhongtian Chen, Fanwu Zhang, Yongzhao Yue
Research on Electromagnetic Immunity Test Method for Vehicle Auto Pilot

In this paper, an electromagnetic immunity test method for vehicle auto pilot in EMC chamber is introduced. The problems such as poor stability of working conditions and field uniformity are analyzed and solved. The feasibility and stability of the test method are verified by the actual test and data analysis. The research shows that millimeter wave radar target simulator and special site processing mode can achieve stable driving condition in EMC lab, and achieve the test condition of electromagnetic immunity test method for vehicle auto pilot.

Ye Tian, Hao Zhang, Baochang Tan, Zhi Jiang, Xianlin Shu
EMC Design for Automobile Rear Windscreen Heater

The noise coupling between the rear windscreen heater and the FM antenna is analyzed with a capacitive coupling model and simulated by using a commercial package in the present paper. The S-parameters between the heater and the FM antenna are calculated. For reducing the coupling, both a physically separating proposal and a filtering proposal are then presented and simulated. The S21 parameter is shown to be effectively minimized in both optimizing proposals. Moreover, as far as a noise coupling issue occurred in the real vehicle is concerned, a 10 dB noise improvement in the FM radio by adopting a filter is successfully achieved and illustrated.

Zhong Yilin, Dang Guangsheng, Chen Xiaohong, Xu Lian, Yang Chao
The Task Distribution Problem Analysis of Vehicle ECU Upgrade via OTA

This paper studies the problem that the vehicle ECU fails to upgrade due to the Firmware Data Package deployed to the vehicle by the OTA Cloud does not match with the vehicle ECU during the process of OTA upgrade. This paper analyses the causes of the problem through bench simulation test and real vehicle test, and research the solutions to improve the reliability and stability of the vehicle ECU via OTA.

Zhining Li, Boxiang Ma, Zeyu Nie, Chonglei Duan, Di An, Baiqi Wang
Proceedings of China SAE Congress 2021: Selected Papers
China Society of Automotive Engineers
Copyright Year
Springer Nature Singapore
Electronic ISBN
Print ISBN

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