Proceedings of China SAE Congress 2022: Selected Papers

Aiming at the electronic and electrical architecture with both OSEK and AUTOSAR network management, we propose a design method for the partial network management. This paper introduces the design principles of network management in the hybrid network, and the cooperative sleep-wake-up strategy of OSEK and AUTOSAR for each node. After verification, the design method proposed in this paper can be applied to the electrical and electronic architecture of the hybrid network, and plays the role of partial network management.

In the electromagnetic compatibility test, the result of RE (radiation emission) is uncertain. When the result is close to the threshold, it is difficult to make an accurate judgment. CNAS-GL07 considers the influence of uncertainty on the decision and prescribes a decision method based on a single test. In this paper, Bayes rule is used to analyze the results of single RE test, which proves that there is a high possibility of misjudgment, and suggests that the number of tests should be increased to improve the reliability of the final decision. The method is improved and perfected on the basis of CNAS-GL07, and the result is good through experiment. It can provide some guidance for the determination of RE test results.

This paper studies the shifting strategy based on an electric bus. According to the development performance requirements of the bus, a dynamic shifting strategy and an economical shifting strategy are formulated respectively. Among them, the dynamic shifting strategy is mainly based on the principle of maximum acceleration to formulate corresponding shifting strategy, and the economical shifting strategy is mainly formulated based on the test data of the motor bench and the characteristics of the vehicle speed and efficiency curve under different accelerator pedal depths. Finally, build an AVL CRUISE vehicle simulation model to simulate and analyze the shifting strategy of the electric bus and a test platform for testing. Simulation and test results show that the proposed shifting strategy is feasible.

By reviewing the automotive key development history, to implement precise location is an essential way of automotive digital key system. This study decides to implement precise location method based on Ultra Wide Band(UWB) technology, following the guide line of briefly stating the ranging principle of UWB, designing three points location model, constructing UWB location deployment model of automotive cockpit, describing location algorithm and work flow of implementation of UWB location method in detail. This paper analyzes UWB location error which is within the theoretical precision accuracy range proved by test data. The advanced design idea tutors optimizing the algorithm, and the implementation of distributed computing of this location algorithm makes the study achieve the best system resources balance and power management goals. The study also implements precise location of automotive digital key based on UWB. Meanwhile the paper shows that automotive digital key fusing UWB location technology matches the direction of automobile intelligence developing.

Hybrid electric drive assembly is currently a relatively new configuration in China, there are a variety of working modes such as driving, power generation and energy recovery, and there are also different working strategy in each mode. Various modes involve more factors, and the calibration of the real vehicle has a great impact on the load distribution, resulting in complex prediction of the load spectrum of each mode. Based on the basic theory of hybrid electric drive, combined with the actual vehicle projects and the distribution characteristics of measured data, the load generation mechanism and distribution of each mode were analyzed, and the load spectrum of each mode was quantified and compared. Based on the distribution strategy of each mode, and platform stratagem was considered, and the special load spectrum envelope design method was constructed for each mode, and the hybrid load spectrum construction method covering multiple vehicle platforms was generated.

Aiming at achieving the national vision of “carbon peak, carbon neutral”, the new energy vehicles have developed dramatically in recent years in China. The growing supply and demand gap of Li2CO3, which is the main raw material for lithium batteries of new energy vehicles, is attracting increasing attentions. In this paper, A predictive Gray prediction model is proposed to estimate the supply of Li2CO3 in the next few years, and to analyze the supply-demand gap and its impact in view of the increase of Li2CO3 price and the great demand of Li2CO3. Then, based on the gray correlation analysis method, a simple game theory model is established, in which the independent variable is built to analyze the game among Li2CO3 suppliers, car manufacturers and battery factories. Results show that the Li2CO3 price has the greatest impact on low-end new energy vehicles, and some suggestions are given to enhance the sustainable development of new energy vehicle industry.

As a new form of intelligent and connected vehicles, autonomous delivery vehicles are a massive increase in the era of autonomous driving. Autonomous delivery vehicles, as a new type of convenient and safe “contactless delivery” tool, have attracted widespread attention from all walks of life amid the fickleness of the new crown epidemic. The large-scale application of autonomous delivery vehicles requires corresponding supporting laws, regulations, and standards. With the release of the innovative autonomous distribution management policies in several pilot areas of intelligent and connected vehicles, such as the Beijing High-level Autonomous Driving Demonstration Area, and the continuous investment of many companies in product technology and applications, China’s autonomous distribution industry may welcome the rapid landing, and a new logistics ecology based on autonomous driving technology will become possible. This technology-driven industrial transformation will eventually bring users a unique distribution experience. Through analyzing the management system and policies of autonomous delivery vehicles at home and abroad, this article aims to provide a reference for promoting the landing of autonomous delivery vehicles in China.

The automotive industry is facing enormous pressure to reduce carbon emissions. Due to its complex industrial chain and close relationship with energy transition, the research on its emissions mitigation strategy is of great significance and urgency. This paper studies the key aspects of the auto and related industries to achieve coordinated emission mitigation. As a vital component of emission mitigation, a carbon accounting framework considering emissions from both product and company’s value chain is established. Carbon emissions of vehicles with different powertrains are compared and automotive company’s life-cycle carbon emissions are studied. Besides, the potential of vehicle to grid and vehicle to everything in emission mitigation is analysed. Practical development countermeasures for automotive industry’s carbon neutrality are put forward.

The demand for computational capacity in intelligent vehicles is increasing rapidly, which drives the automotive industry to accelerate the integration with the information and communication technology industry. This study evaluates the demand for computational capacity from three levels: vehicle, driving environment and industrial chain. Based on deductive reasoning method, it is revealed that to realize the increase of computational capacity, the technical architecture of vehicles needs to be reshaped, the driving environment needs intelligent upgrade, and the industrial chain needs ecological development. Then, according to the development needs of relevant technologies and industries, brand-new market competition strategies, business relationships and ecological evolution paths are identified. Finally, some suggestions are put forward to original equipment manufacturers, chip enterprises and information and communication technology enterprises, which are related to computational capacity of intelligent vehicles.

The development of shared mobility is short and unbalanced. To promote a healthy development of shared mobility enterprises, in this study, the development trend of shared mobility from the perspective of market pattern, market capacity, and market ecology based on relevant data is analyzed. The business models of three typical enterprises, Didi, CaoCao, and Uber, are then analyzed from the perspective of value proposition, profit model, promotion model, and operation model, and then from the perspective of integration of resources, mode guidance, and technology driven to build the China’s shared mobility enterprise development hierarchy. Finally, from the perspective of new models, advanced technology, and industrial integration, development strategies and suggestions for future shared mobility enterprises are presented.

In the in-depth investigation of road traffic accidents, it is significant to ensure the reliability of the data source and the representativeness of samples in the database. A sampling investigation model is proposed based on regional traffic conditions and traffic accident data, and a regional transportation and accident characteristics evaluation system is established. Several regional transportation indicators are defined to divide relatively balanced regional sampling units(RSU) based on adjacent administrative divisions. The regional accident indicators are divided into two categories: accident scene classified index and accident damage evaluated index. Analytic Hierarchy Process(AHP) is adopted to calculate the weights of each type of scene according to the accident damage. The group of weights is applied to stratify the accidents in each RSU. It is also necessary to take into account the cost of sampling in practical investigation work. A two-stage sampling investigation model is established, which integrates regional indicators and investigation costs. The total number of accident samples is determined according to the given budget. In the first stage, the regional units are randomly selected. In the second stage, the accident cases are stratified and sampled in the selected units. The entire framework is experimentally implemented with data from Guangdong province, China.

Based on the requirement of improving the simulation accuracy of pedestrian protection of automobile windshield glass, the influencing factors of the simulation accuracy of the front windshield are studied from three aspects: impact position, material parameters, and modeling methods. The following conclusions are drawn: (1) The closer the distance between the impact point and the interior instrument panel and the black belt boundary, the greater the head damage value; (2) The greater the glass yield stress, the larger the initial peak value of the damage curve. The reduction of the glass plastic hardening modulus, glass failure plastic strain, interlayer Young’s modulus, interlayer yield stress, interlayer plastic hardening modulus will reduce the valley value after the first peak to a certain degree; (3) The rigid connection method of the fixed point of the instrument panel will lead to a larger secondary peak of the damage curve, and the head damage is too large; At the same time, it is recommended to use the method of taking the impact point as the center and radiating to the surrounding for glass meshing, which can effectively simulate the cobweb-like breaking form in the glass impact test and improve the simulation accuracy.

In order to increase the C-NCAP rating score of a certain developing vehicle under 50FFB and 64OBD crash conditions, the weights of Injury Criteria are calculated, and a DWIC (Dynamic Weighted Injury Criteria) optimization objective is proposed under these two impact conditions. The sensitivity analysis method is used to determine the main factors of occupant injury, then the optimal Latin superelevation method is utilized to design the test matrix, acquiring 64 groups of calculation results. Based on this, the surrogate model of restraint system with DWIC formula is established. Finally, multi-objective optimization is achieved with NSGA-II algorithm to obtain the optimal parameters of the constrained system. The results show that the head and neck injury criteria of driver are reduced by 19.2% and 25.9% respectively, improving 50FFB score by 1.31 points. Rating score under 64OBD condition is improved by 0.94 points. Compared with the original weight, the score improvement is increased by more than 30%. Thus, optimization process based on DWIC is proven to be effective in achieving better rating score for specified vehicle model and evaluation procedures, which would be further used in MPDB tests.

A distributed modular flexible man-machine verification model control system has fast response, flexible adjustment and expansibility through Internet of things technology and modular circuit design. It can meet the immediate needs of the verification and layout scheme of man-machine experiment in the early development of passenger cars, reduce the development risk and provide a good user experience.

Twist beam axle (TBA) is a common type of rear suspension for passenger cars. In this paper, the historical development of TBAs has been systematically reviewed at first. Their structural and kinematic characteristics, advantages and disadvantages have been summarized. Subsequently, more than ten new technologies with aspect to structure, manufacturing process, material, design software, etc., for further development of TBAs in recent years have been introduced and discussed. At last, future prospectives of TBAs under the trend of vehicle lightweight and electrification, chassis platform design and active control have been outlined.

Aiming at the problem of big resistance of the high speed amphibious vehicle sailing in water, the model test method is adopted to study the influence of different bow and stern flaps on the resistance characteristics of an amphibious vehicle. The results show that the resistance of the amphibious vehicle studied in this paper reduced effectively with the installation of bow and stern flaps. The installation angle of bow and stern flaps has great influence on the ship resistance, and the resistance is the smallest when the installation angle of the bow flap approaches 10°, moreover, the resistance decreases with the increasing of the installation angle of stern flap. The effect of bow and stern flap on the trim angle of amphibious vehicle is closely related to Fr▽. The trim angle increases with the installation of bow and stern flaps when Fr▽ < 1.075, but it decreases when Fr▽ > 1.075, and more benefits are obtained with higher speed.

This paper proposes a motion control strategy for the wheel-legged compound unmanned vehicle, including attitude control and driving control. Firstly, based on tire mechanics, Lagrangian method and D’Alembert’s principle, the dynamic modeling of the driving system, wheel-legged system and vehicle body is carried out respectively. On this basis, a layered parallel control architecture is proposed. The upper-level controller consists of a driving system controller and a wheel-legged system controller. The former is used to control the longitudinal, lateral and yaw motions of the vehicle based on the model predictive control method, and the latter is used to adjust the longitudinal, pitch and roll motions of the vehicle based on PD control. The lower-level controller is used to control the output torque of the vehicle motor based on the PI control method. Finally, three typical working conditions are designed to verify the attitude control and driving control of the vehicle. The simulation results show the accuracy and stability of the designed controller to track the target command.

Ducted fan is a potential propulsion unit for flying cars in the future, and it has a wide range of application prospects. In ground effect, due to the aerodynamic interference with the ground, the ducted fan easily enters an unstable state caused by rotating stall. In this paper, a simulation platform is built based on a modified MG model, and the simulation of the ducted fan in ground effect is carried out for hovering and landing conditions. The static and dynamic effects of the ground effect are discussed in detail and the sensitivity analysis of parameters is carried out. The results showed that the instability of the ducted fan increases with the decrease in altitude or the increase in speed under hovering conditions, while it doesn’t occur under landing conditions. In addition, the study pointed out that the pressure rise characteristics and flow characteristics of the ducted fan have a significant impact on its instability. The combination of high peak pressure rise coefficient and low corresponding flow coefficient can effectively improve the stability.

Aiming at the low frequency abnormal vehicle vibration caused by engine sources, the process, key points and difficulties of synchronous combustion analysis are introduced in detail, especially the idea source of cylinder pressure external envelope post-processing method is emphasized. Firstly, the combustion and vibration data of four cylinders was collected and analyzed by synchronous combustion analysis method, and the external envelope post-processing method of cylinder pressure data was proposed for the first time. Secondly, by analyzing the cylinder pressure after envelope post-processing method, it was found that the root of abnormal order problem was the periodic lag caused by the pressure of each cylinder of the engine. In the detailed analysis of the cylinder pressure, the hysteresis law was determined as “2–4-3–1”. Finally, by optimizing the calibration data, the abnormal order vibration peak of the driver’s seat was reduced from 0.25g to 0.01g, which effectively controlled the low-frequency vibration of the vehicle.

This paper takes the electric drive system used in the electric vehicle as the research object, in which the objective sound quality of noise samples is extracted and evaluated based on the kernel principal component (KPCA) analysis method. Seven different power-level prototypes and their related parameters are firstly presented, while the sample library under different operational conditions has been established. Secondly, the KPCA method is employed to extract the contributions of eight objective psychological features. The results show that the KPCA method can effectively achieve multi-dimensional feature extraction. The cumulative contribution of sharpness and tonality is meeting 98.18%, which can fully represent the objective sound quality. Moreover, the sharpness and tonality are more sensitive to the speeds under different load conditions. Especially, tonality obtains a different pattern with SPL-A above 10000 r/min. This work can provide a theoretical and practical basis for predicting and optimizing the objective and subjective sound quality in electric vehicle applications.

A SUV vehicle equipped with 1.4T engine and 6AT automatic transmission has an impact abnormal noise in the engine cabin during the low speed launching condition, which seriously affects the driving comfort performance. Based on the results of vehicle vibration and noise test and analysis, combined with the transmission power flow analysis of the D gear and R gear, as well as the theoretical assumptions of transmission clearance and rattle phenomenon, it is identified that the abnormal noise key element is the spline clearance of the intermediate output shaft driven gear. In addition, adopting the optimization of spline matching design parameters, the effectiveness of this counter-measures is verified by the vehicle driving subjective evaluation and objective test. This has important engineering guidance value for solving the driveline NVH problems under transient conditions.

In order to analyze the influence factors of vehicle interior gear whining order noise from the mechanism, a time-domain hybrid analysis model of gear whining is built in this paper. The acceleration of the mount’s active side and near-field noise result is acquired mainly based on the time-domain dynamic multibody model. Then the result data is used as input and loaded into the vehicle time-domain transmission path mathematical model, so as to calculate the vehicle interior gear whining order noise through virtual analysis. Compared with the real vehicle test results, the frequency error of the vehicle interior gear whining order noise calculated by this method does not exceed 6%, and the amplitude error does not exceeded 12%. On this basis, the method is applied to analyze the sensitivity of the factors affecting the gear whining on a certain vehicle type. It is found that the tooth shape modification and high-frequency vibration isolation of the mount etc. are the main causes of the vehicle interior gear whining. After the verification of the real vehicle test, the good accuracy of this modeling method is furtherly proved, which provides a powerful technical reference for the industry to solve this problem.

The angles between the drive shafts and the power output shaft (hereinafter called the angles of the drive shafts) will generate the axial force. Excessive axial force will cause the vehicle to swing laterally. A vehicle, which appears lateral swing when accelerating at wide open throttle in third gear, is found that the frequency of the third-order vibration of the drive shafts is in good agreement with the frequency of lateral swing. The test result of the coordinate measuring machine (CMM) shows that the value of the angles of the drive shafts is larger than the design value. After reducing the angles of the drive shafts by adding weight, the lateral swing of the vehicle (hereinafter called lateral swing) is significantly weakened. In order to exclude the influence of the weight on the test results and considering the space constraints of engine room, the length of suspension spring is changed to reduce the angles of the drive shafts, and both subjective evaluation and test results show that the lateral swing is significantly weakened. Therefore, that the lateral swing is strongly related to the angles of the drive shafts is verified. This article could provide reference for the analysis of the lateral swing.

Fine simulation and bench tests were carried out based on the longitudinal and variable thickness composite leaf spring. The test results show that the deviation between the stiffness simulation and the bench test is less than 1.5%, and 500000 times of single composite leaf spring bench test, the vehicle four-channel bench test, and the vehicle load-bearing system endurance test have been passed. The simulation and bench test specifications are established to provide technical support for similar products to pass the tests at one time and shorten the product development cycle.

Through the analytic hierarchy process, this paper finds out that the pressure distribution on the hip area, leg area and waist area of the seat has a great influence on the subjective evaluation. The effectiveness of subjective evaluation method is verified through the correlation analysis between pressure distribution and subjective evaluation with the adoption of binary linear regression and curvature regression methods, which offers the theoretical basis for seat comfort design.

Welding is a key process in automobile body manufacturing, and its quality has an important impact on the connection strength and paint quality of vehicle body. It is worth noting that long-distance spark splashing during welding will not only damage the body paint, but also pose a threat to the personal safety. It is found that welding parameters are the direct factors affecting spark posture and splash distance. Therefore, the selection and optimization of welding parameters is very important. Aiming at the control of spark splashing distance during welding, this paper selects the welding process parameters that have the greatest impact on spark posture and splash distance: welding current and welding time, and uses fully connected neural network, Bayesian regression and Gaussian mixture model to mine the implicit relationship between spark splashing distance and the selected welding process parameters, the optimal welding process parameters can be deduced through the hidden relationship, so as to improve the quality, efficiency and safety factor of body welding.

This paper aims to study questions about the thread cone angle of the cone lock-pin synchronizer used in the gearbox of a vehicle model, such as unstable measurement accuracy and single quality control method. This thesis introduced the basic working method of the equipment for testing the thread cone angle developed according to the tangent trigonometric function. The experimental data reported that the limitation and unreasonableness in the design of its original measuring mechanism were the main reasons that the measurement accuracy was unstable. Therefore, we selected another angle measuring scheme, that is, to develop new test equipment using the method of calculating the radian and then rotating the angle, and optimize the structure of mechanical measuring head to improve the measurement accuracy and reliability of the synchronizer’s thread cone angle, finally realizing that the processing quality of synchronizer parts was under control.

Involute spline broach is one of the main tools for processing internal splines in our company, which has the characteristics of complex structure and high cost. This paper focuses on the analysis of the reasons for broach wear, introducing the control method of the wear loss, and giving a detailed discussion of how to sharpen the broach correctly. Finally, a “Five-Step Operation Method” for cleaning and finishing the blade is proposed, which greatly improves the defects of the broach after sharpening as well as the processing quality of the workpiece, so as to prolongs the service life of the broach.

The tolerance analysis by linearized method could be used to confirm the tolerances of the different parts of body assembly, and to ensure the accuracy of the gap and flush of body-in-white assembly. Key parts and dimensions could be found by this way. The process capacity target, PPK, and I-MR control charts are considered as the way to control the quality of parts. The forward direction quality control model for body assembly is constructed by those two methods above, and that means the targets of the dimensions of body assembly could be reflected on dimensions of parts, and should be quantifyed. Based on the forward direction model, precision of parts is supervised, and this means it provides a fact to rectify parts. And this is reverse direction quality control model. Considering Time series of the parts and assembly, Bayesian theory was used to modify the datas, and also Correlation Coefficient could be calculated, in order to know the exact Contributions parts was made to the quality of body assembly.

By studying the Aluminum alloy high vacuum die-casting shock tower, the problems of casting deformation and high energy consumption of the traditional shock tower are solved through the research of heat treatment-free materials. In the casting rod statement, the developed Al-Mg series Aluminum alloy has a property of YS ≥ 160 MPa and A% ≥ 13%. The integrated structure design of the shock tower is carried out to achieve a weight reduction of 29%; the developed materials are used for trial production, the YS ≥ 170 MPa, and A% ≥ 8.5%, the gas content is 1.76–2.03 ml/100g Al, which meets the performance requirements of the shock tower.

In the last years, press-hardened steel (PHS) plates have been used to manufacture lightweight car body parts widely to meet the increasingly stringent regulations for reducing fuel consumption and greenhouse gas emissions while promoting passenger safety. Using electronic universal testing machines, metallographic microscope, scanning electron microscope (SEM) and corrosion test chamber, the mechanical and corrosion performances were investigated between AlSi75 and AlSi30 samples. Results show that the coating transforms from a two-layer structure into a five-layer structure, and the microstructure transforms from ferrite, carbides and pearlite into martensite and retained austenite after hot press forming; the tensile properties, hardness and bending angle for both PHS samples are basically the same, but the maximum bending force of the AlSi30 samples are 16% larger than that of AlSi75; After neutral salt spray (NSS) tests, the AlSi75 samples exhibit more excellent corrosion resistance than AlSi30 samples. And the corrosion depth of AlSi75 and AlSi30 samples exceeds 38 μm and 159 μm, respectively; the α-Fe layer for both PHS samples is left to protect the substrate from further corrosion after vehicle cyclic corrosion (VCC) tests. But the AlSi75 samples also show better corrosion resistance. The corrosion widths of AlSi75 and AlSi30 samples are 2.51 mm and 3.83 mm, respectively.

To resolve the issues of poor load-carrying performance, high-speed instability and complex structure for airless tires, the re-entrant hexagonal airless tire with negative Poisson’s ratio is proposed. To start with, thickness coefficient $$\alpha$$ α , length coefficient $$\beta$$ β , angle between side unit beam and unit axis, and re-entrant angle of the two sides are regarded as design variables, the calculation model of relative density is derived. Meanwhile, response surface models of specific energy absorption and peak collision force of unit cell are established by constructing finite element models. On this basis, optimal structural parameters can be achieved by adopting genetic algorithm with the objectives of maximum specific energy absorption, minimum peak collision force, and minimum relative density, and with the constraints that length coefficient and thickness coefficient are less than 1 and unit cell is possessed with the characteristic of negative Poisson’s ratio. Subsequently, the effects of various support structural parameters on mechanical properties of airless tires are analyzed and compared with conventional hexagonal honeycomb tire of the same specifications. The results indicate that the energy absorption and 1st modal vibration frequency of proposed airless tire increase by 10.76% and 27.84%, separately. Meanwhile, peak stress and mass decrease by 38.69% and 13.52%, respectively.

In this paper, a 1.5L turbocharged DI gasoline Hybrid-engine is taken as the research object, and the effects of LP-EGR system on fuel consumption and combustion are analyzed through experiments. The LP-EGR system taking the air behind the catalytic converter can achieve an EGR rate of 28% in the low fuel consumption area. Combustion stability is the reason that restricts the further increase of EGR rate. With the increase of load, the maximum EGR rate decreased gradually and the effect of EGR on fuel consumption reduction is more obvious. In addition, the advance amount of AI50 basically remained unchanged, while the extension amount of combustion duration gradually decreased, and EGR rate had little influence on combustion duration at high load.

Vehicle supercharged engine is more likely to induce knock due to its working characteristics. Super knock can reduce the performance of engine and damage the engine for a short period of time, but the power and fuel economy will improve when the engine working at the slight knock state. In this paper, a systematic study is carried out to identify knock based on the knock sensor signal, which is designed to improve the accuracy of knock recognition and knock intensity determination, ensuring that the program can adjust the control parameters according to the strategy, so as to effectively suppress the continuous knock. The results show that the method studied in this paper can accurately identify the knock phenomenon and evaluate the knock intensity based on the sensor signal.

In the present study, the structure of by-pass valve and the key influencing factors of bypass valve control were introduced in details; the STAR-CCM+ software and finite volume method were applied for numerical simulation research, so as to obtain the exhaust gas flow through turbine and exhaust gas by-pass valve; the coupling effect mechanism of the actuator voltage range and the by-pass valve pipe diameter on the by-pass gradient was further explored through analysis. The numerical simulation results show that the reduction of the actuator voltage range and the by-pass valve pipe diameter can both effectively lower the by-pass gradient, with the shortening of the actuator voltage range much more effective; the reduction of bypass ratio gradient is beneficial to the turbocharger actuator; the goodness of fit between the CFD simulation result and the test result was high, indicating that the simulation method can effectively address the difficulty in the control of engine supercharger.

In this paper, we propose a method to make intelligent vehicles complete lateral lane change control, longitudinal overtaking control, and path planning of cloud computing network-connected road sections with the support of roadside-end fusion detection equipment. Also, we simulated the actual scenario of intelligent vehicles and vehicle detection equipment between the data communication and complete the communication test in the simulation scene of the sand table model. As for roadside detection equipment, different detection equipment is customized according to the traffic flow and traffic scenarios of real urban roads, sensors such as lidar and cameras are fused, and roadside information monitoring and vehicle scheduling are completed in combination with roadside units and computing platforms. As for the intelligent vehicle navigation module, lidar and binocular cameras are used for SLAM mapping, and the vehicle is accurately positioned with the help of the camera and Tag code. The simulation-to-real environment will improve the vehicle positioning accuracy through the WIFI module. For the intelligent vehicle control module, it provides real-time roadside information to the vehicle, which completes the tests of vehicle road driving, marker recognition, and traffic light detection in Gazebo by cameras and lidars.

Obstacle detection and tracking is an integral part of the autonomous vehicle perception algorithm. Because most of the existing tracking algorithms have the problems of insufficient accuracy and poor real-time performance, an obstacle detection and tracking method based on LiDAR is proposed in this paper. Firstly, for the scene with the undulating ground in the environment, a twice-ground segmentation method based on plane fitting and scan line geometric features is proposed to accurately and robustly extract the high obstacle point cloud. Secondly, the density clustering algorithm is optimized, and a convex hull rectangular 3D bounding box fitting algorithm is proposed to detect obstacles. Finally, the Mahalanobis distance measurement feature is used to realize the data association between the previous and the current frame. And the interacting multiple model filter algorithm embedded in the unscented Kalman filter is used to estimate the state of the object optimally. Based on the public data set, the proposed algorithm improves the accuracy of tracking detection. After verification on the self-developed real vehicle experimental platform, the results show that the algorithm has good object tracking and correlation performance.

In order to solve the visual SLAM technology when applied to autonomous driving position facing the accumulation of drift problem such as larger and tracking lost, based on the closed zone autopilot visual inertial positioning system as the research object, based on the characteristics of optical flow tracking and adaptive depth estimation of visual front-end, accord with the actual motion constraints of the vehicle kinematic model was constructed. Based on the tight coupling optimization method of sliding Windows, visual inertial joint pose optimization under vehicle model constraints was realized, and a loopback detection algorithm was designed considering geometric constraints of image feature space. Finally, KITTI data set and real vehicle verification are carried out, and the results show that the proposed method can effectively improve the accuracy and robustness of the visual inertial positioning system for autonomous driving in the enclosed park, and has significant engineering application value.

The automatic emergency braking system (AEB) of intelligent automobile is prone to false triggering or failure in curve environment. This paper presents a hierarchical AEB objective detection and predictive control methods under two typical curve conditions: curving road, turning into straight road. In the upper layer, a geometric curving compensation method is developed to detect the potential collision target in curving condition. Then, the inversed of Time To Collision (iTTC) and risk effective factor ( $$\gamma$$ γ ) calculated based on the relative states of self-vehicle and potential target are used to determine the expected. A hybrid predictive control-based speed tracking algorithm is designed in the lower control layer, where the tire braking force characteristics are systematically analysed and the braking force model are converted into a mix logical force model to accommodate the tire force saturation situation. Finally, the co-simulation and car-like robot test are carried out to verify the feasibility and effectiveness of proposed strategy.

In the present research on automatic parking, there are few automatic parking on multi-vehicle scheduling, and the simulation of the scene is relatively simple. In this paper, a multi-vehicle scheduling parking management method is proposed, and the scene of a double-deck parking lot is used in the simulation experiment. In the experiment. We preset a parking time for each vehicle so that the algorithm can classify the vehicles based on their parking time. Vehicles with shorter parking times will be arranged in the parking lot on the first floor which is closer; vehicles with longer parking times will be arranged in the parking lot on the second floor which is farther away. First, we studied the motion action and parking process of the vehicle, and a kinematics model is built. Secondly, we built the model of vehicles and a double-deck parking lot with SolidWorks. At the same time, the sensors are configured for the vehicles, and the models are imported into Gazebo. Then, we use line patrol navigation to allow the vehicle to move to the parking lot on different floors according to the patrol lines of different colors, completing the path planning of a single vehicle from the starting point to the parking space through ROS communication. Finally, utilize the parking management node to divide all vehicles into various units, and then schedule parking management for each unit separately, completing the automatic parking of the total vehicles. The results demonstrated that scheduling with 2 vehicles as the minimum unit is about 30% faster than scheduling with 1 vehicle as to the minimum unit.

Interactive scenarios are of great significance for the testing of high-level automated vehicles. Based on the structure of Generative Adversarial Network (GAN), the Interactive Trajectories GAN model (ITGAN) is proposed in this paper. This research comprehensively considers both of the dynamic interactions between agents and the responses of agents to the static road environment. ITGAN consists of a specially designed pair of generator and discriminator, which are trained iteratively in an adversarial manner. As a data-driven agent model, ITGAN has the ability to generate agent interactive trajectories just like those from the real world. In order to verify the utility of ITGAN, experiments are conducted with the co-simulation framework of CARLA and SUMO, where ITGAN is implemented as the external agent control model to help generate interactive driving scenarios on various types of urban roads. By the qualitative and quantitative analysis of the experiment results, it shows that ITGAN can produce more effective interactive scenarios compared with the traditional agent model and has great potential to supplement the deficiencies of existing testing methods for high-level automated vehicles.

Accurate estimation on the perception performance is an essential prerequisite for autonomous driving safety. State-of-the-art perception models get excellent performance on existing well-labelled dataset, while suffering the lack of reliable confidence in varying scenarios. This paper is dedicated to investigate an online perception performance estimation, in particular, to calculate the precision rate of each detected object adaptively without manually labelled annotations. A parameterized relationship is constructed between the confidence output by perception models and the precision performance. And then the relationship can be online updated according to a robust multiple hypothesis tracking (MHT) system iteratively. The proposed method is applied on widely studied Mask-RCNN on the KITTI dataset, to get precision estimations accordant to the ground-truth in different scenarios, respectively.

With the increasing connectivity of the modern automotive, cybersecurity is becoming increasingly essential for an auto. Security by design is a recommended way to protect automotive systems rather than after-sale solutions. However, other than cybersecurity, an auto should also be safe and comfortable to transport people and cargo. How to achieve a trade-off design considering various system requirements is a challenge. In this paper, a trade-off design approach for integrating various aspects, like cybersecurity, safety, and user experience, is proposed. The affecting map and the affecting score are proposed as tools to help the designer to select proper security countermeasures qualitatively or quantitatively. The proposed methods are compatible with the international standard ISO/SAE 21434. A case study of a Diagnostic on Internet Protocol (DoIP) system is demonstrated with details to show how to use the proposed methods, and also verify the feasibility and effectiveness of the approach.

This paper studies the correlation between driver fatigue state detection and dangerous driving behavior. The fatigue measurement method adopts the gold standard of the industry, namely EEG fatigue detection method. The driver's original EEG signal was preprocessed, the EEG signal artifacts were removed, four typical EEG rhythm waves were constructed by wavelet packet decomposition and reconstruction algorithm, and the frequency band energy ratio was calculated to judge the fatigue degree. Aiming at the dangerous driving behavior induced by fatigue, the data of steering wheel Angle, vehicle acceleration and speed collected synchronously were processed and analyzed by sample entropy algorithm. Based on Pearson correlation coefficient, the co3rrelation between EEG frequency band energy ratio and dangerous driving behavior index was analyzed. It is found that the steering wheel Angle control is most susceptible to the influence of fatigue and fluctuates dangerous driving behavior, and the correlation between the sample entropy of steering wheel Angle of dangerous driving behavior and driver fatigue state is the strongest.

ISO 26262 is a functional safety standard for Automotive Electrical and Electronic systems. Hazard Analysis and Risk Assessment (HARA) is an important sub-phase in the ISO 26262 safety lifecycle. For HARA of Electric Power Steering (EPS), it is difficult to classify S(severity) and C(controllability). In most cases, S and C are classified through brainstorms. This is subjective and not instructive for HARA of EPS. This paper proposes a quantitative analysis method to classify S and C in HARA of EPS. This paper is divided into two parts: the first part will introduce the processes in the concept phase, for item definition and HARA. In the item definition process, the functions, boundaries, and external interfaces for the product are defined. In the HARA process, situation analysis, hazard identification, and classification of hazardous events are performed. The second part will present the quantitative method to evaluate S and C based on “No steering assistant torque” in EPS. The quantitative analysis includes simulation method and experimental method which provide guidance for the classification of S and C for HARA of EPS.

According to the technical rules of Formula Student China (FSC), a set of small displacement mechanical supercharging system with speed regulation by electric assistant function, is based on a technical route which called “response enhancement technology”, invented by Gspeed Formula Student racing team. The process of theoretical calculation, the supercharger selection, motor selection, and design of the differential gear system to achieve speed regulation are also proposed following. The Variable Speed Mechanism consists of a battery-powered brushless DC motor controlled by electronic governor as the auxiliary drive source. A differential gear train is used to coupling the power input from motor and engine. The final transmission realized by 5PK belt drive. To avoid the failure of the system by motor broken, a one-way clutch is used to limit the reverse rotation of the motor. For speed regulation, three sets of schemes were developed according to different target focuses. 1-D CFD simulations software GT-Power was used to build up the supercharged engine model. The multi-body dynamics simulation analysis software VI-CarRealTime was used to simulate the laps. The results show that this system matches well, achieves the expected performance target, and has great potential in practical development and application.

Upright is an important part of the suspension structure of the racing car. It is an essential part of the wheel assembly to connect with the whole body of the vehicle. Under the high frequency and high amplitude acceleration, it is prone to cause fatigue failure due to alternating load. So, it is of great importance to analyze the fatigue life and strengthen the low fatigue life for the structure. This thesis focuses 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, and the load spectrum at the upright is extracted. Considering the fatigue analysis results and the fatigue failure example of the previous racing car’s upright, the structure of the part is further optimized. The optimized left rear upright reduces maximum stress by nearly 45%, increases mileage by nearly 5.33 times, and reduces mass by nearly 15%. While optimizing the structure strength of the upright, the fatigue life of the upright is extended and the lightweight design is further realized.

Structural crash optimization can find the best balance between the crashworthiness and lightweight performance of the structure. However, structural crash topology optimization is a typical optimization problem of structural nonlinear dynamic response, and it is the most complex optimization problem at present. In this paper, the novel crash optimization is proposed by combining the Equivalent Static Loads Method (ESLM) and Energy Principle (EP). The ESLM is used to transform the complex crash optimization problem into the static optimization problem. The EP is used to calculate the dynamic load factors that can scale the Equivalent static loads (ESLs) and ensure the static optimization problem under ESLs in linear range. Furthermore, the proposed method is used to optimize the frame structure of Formula SAE (Society of Automotive Engineers) under the crash load. Finally, by comparing the structural performance before and after optimization, it is shown that the method can realize the lightweight design of the racing car structure under the premise of ensuring the crashworthiness of the structure, so as to provide an effective method for the structural optimization design of Formula SAE.

After the University formula auto race was introduced into China in 2009, it quickly became an innovative practice activity for college students that many college students are willing to participate in. Due to the restrictions of the competition rules, FSC racing cars use engines with a displacement of less than 710 cc and need to pass through a 20 mm flow limiting valve (1). Firstly, this paper uses MOTEC M800 to calibrate and match various sensors. Secondly, on the bench test, the engine ignition, fuel injection map and the auxiliary correction of environmental parameters to the ignition advance angle and fuel injection pulse width are carried out, so as to achieve the maximum power of the engine under the rule limit. Finally, in order to improve the driver's operability and combine the characteristics of the track, the traction control and launching control functions are introduced. The launching control and traction control are determined through the running state of the whole vehicle, the driver's feedback and I2 data. Make the power system of the whole vehicle have strong competition.

The research content of this paper is based on a small three-cylinder FSAE racing engine, designed and manufactured a kind of continuous variable intake system, including a new variable intake manifold length control mechanism and its control program. At the same time, lightweight is used throughout the race car design, which is also one of the important design concepts of this research. Through a variety of simulation methods, the geometric parameters and structural performance of the intake system are optimized to achieve a wide range of torque enhancement and lightweight design of the entire system.

By comparing with the traditional wet sump lubrication system, the advantages of the dry sump lubrication system in terms of overall vehicle operational stability and engine stability are highlighted. The dry lubrication system and the use of dry lubrication system significance, detailed introduction of the dry lubrication system oil pump selection, dry sump design, oil tank design and oil filter mounting base design. Based on the performance requirements of FSCC engine conditions for lubrication, the requirements for each component are presented, along with competitive design requirements, and finally the design is carried out to determine the optimum solution based on the requirements. The completed dry lubrication system is systematically tested to check the feasibility and reliability of the design solution and to verify whether the lubrication system is competitive enough in the competition.

The reduction of driving range of electric vehicles in winter is a key issue that affects the promotion of new energy vehicles and the implementation of “Carbon peak and carbon neutral” strategic goals. In this study, typical battery electric vehicles in Changchun were selected to obtain the actual road driving data, to analyze the travel and charging temperature, travel characteristics in winter. Two typical temperatures are recommended for the test: take −10℃ as the general and −20℃ as the limit environmental temperature. Finally, based on the driving characteristics, it proposed a low-temperature energy consumption test can better reflect the actual road energy consumption level of BEV in low-temperature.

Efficient and uniform battery preheating is vitally important to improve the poor performance and safety hazards of lithium-ion batteries (LIB) at low temperatures. All-climate battery (ACB) is a novel battery structure that enables rapid self-heating of LIB without requiring additional power sources, but it also leads to an extremely non-uniform distribution of internal temperature and thus capacity degradation. In this study, a variable duty cycle control strategy for heating of ACBs at low temperatures is proposed to make an optimal trade-off among heating time, capacity consumption and temperature gradient during heating based on a nondominated sorting-based multi-objective evolutionary algorithm, called nondominated sorting genetic algorithm II (NSGA-II). Results show that this heating strategy can heat LIB from −20 ℃ to 25 ℃ within 424.93 s and with small temperature gradient. Under the same maximum temperature gradient limit, the proposed method shortens the heating time by 14.20% compared with the traditional constant duty cycle heating strategy, and by 8.65% compared with the constant duty cycle optimal heating control strategy optimized by the NSGA-II algorithm.

The fire problem of new energy vehicles caused by the thermal runaway of lithium-ion batteries has been the pain point of the development of the industry. Thermal runaway has become a bottleneck problem restricting the development of new energy vehicles. In this paper, a thermoelectric coupling abuse model of NCM lithium-ion battery is established, taking into account the internal heat generation and external heat transfer. Using temperature as a coupling factor, a thermal runaway model of thermal abuse of lithium-ion batteries is established. The effects of different parameters on the thermal characteristics of lithium-ion batteries are analyzed, and the thermal runaway characteristics and development rules of lithium-ion batteries under different abuse conditions are revealed.

Ultra-high-speed permanent magnet synchronous motor (PMSM) is widely used to drive fuel cell air compressors and electric turbochargers, and its high efficiency and stable control is an effective way to improve the power density of automotive power systems. Considering the installation space and detection reliability, the automotive ultra-high-speed PMSM is generally not equipped with a rotor position sensor, and the required high-precision rotor position information is obtained by a position sensorless control algorithm. The traditional position sensorless control method based on the extended back electromotive force (EEMF) uses the PI observation error compensator to estimate the EEMF for position estimation. The PI parameter tuning is complicated, and the position estimation error becomes larger with the motor parameters change, which is easy to cause control failure. Therefore, a novel EEMF-based position sensorless control method based on the extended state observer (ESO) is proposed in this paper. Using the ultra-local model of the EEMF, the disturbance term is observed by designing the ESO. The estimated EEMF used for position estimation is calculated by a tracking differentiator. This method is simple to be tuned and can not only obtain more accurate rotor position information but also suppress the disturbance of motor parameters to a certain extent. Finally, the effectiveness of the proposed position sensorless scheme is verified on a 15 kW ultra-high-speed PMSM by simulation tests.

In the process of gear shift and speed regulation of electric vehicles, in order to solve the contradiction between short speed regulation time and small gear shift impact in permanent magnet synchronous motor speed regulation system, a modified tracking differentiator-decoupled active disturbance rejection controller (MTD-DADRC) was proposed. It was applied to the speed loop control of permanent magnet synchronous motor vector control system. The decoupled active disturbance rejection controller was designed through the frequency domain analysis of the ADRC system. The decoupled active disturbance rejection controller improves the stability and anti-noise ability of the system and expands the parameter selection range of the tracking differentiator. On this basis, the tracking differentiator was improved by introducing nonlinear function and terminal attractor function to improve the speed tracking performance of the motor. Compared with the traditional PI controller, the MTD-DADRC proposed in this paper has the advantages of high control accuracy and good tracking performance. Thus, it can effectively shorten the gear shift and speed regulation time while reducing the gear shift impact.

Electrochemical impedance spectroscopy (EIS) establishes the relationship with the internal electrode processes of the battery through the impedance of different frequencies. EIS can be used to estimate and diagnose the internal state of the battery, which has attracted more and more attention. For an on-board application or offline maintenance application, on the one hand, it is necessary to quickly grasp the EIS in the process of battery state change, on the other hand, it is necessary to shorten the maintenance time as much as possible. Therefore, improving the EIS measurement speed has become a key issue. The EIS measurement of general impedance measurement equipment often used in the laboratory takes a long time and cannot meet the needs of practical application. The difficulty of improving EIS measurement speed lies in finding an appropriate disturbing signal and efficient impedance calculation algorithm. Therefore, this paper compares and analyzes the performance of the different EIS fast calculation methods in dealing with different harmonic signals, and makes a comparative study on the aspects of error distribution and calculation speed. The results show that S-transform and sum-of-sines signals have more advantages in the fast and accurate calculation of EIS, which guides engineering applications.

To reduce energy consumption of electric vehicles (EVs), based on the mechanism analysis of deceleration condition energy consumption, an adaptive energy recovery control strategy is designed, which takes the traffic condition, driver’s decelerating driving habits and road slope into consideration. Real-world tests are carried out under three typical working scenarios. The results demonstrate that compared with rule-based energy recovery strategy, the proposed adaptive energy recovery control strategy can reduce the energy consumption by 4.36%, 3.55% and 0.85% under mountainous, suburban and high-way scenarios, which proves the effectiveness of the proposed control strategy.

In this paper, six light-duty gasoline vehicles meeting China VI emission standard were selected for cold start Worldwide Light-duty Test Cycle (WLTC) tests, including two vehicles with Port Fuel Injection (PFI), two vehicles with Gasoline Direct Injection (GDI) and two vehicles with Mixed Fuel Injection(MFI). A new condensing particle counter which can measure fine exhaust Solid Particulate Number in the particle size range of 10 nm–2500 nm (SPN10) was used in conjunction with the condensing particle counter which can measure exhaust Solid Particulate Number in the particle size range of 23 nm–2500 nm (SPN23) recommended by the China VI emission standard to simultaneously measure the Solid Particulate Number (SPN) of the test vehicles. And the total amount of particulate matter emissions (#/km) and transient emission (#/cm3) of light duty gasoline vehicles were obtained. The results indicate that the amount of particulate matters emitted by gasoline direct injection vehicles is higher than that of mixed fuel injection vehicles, and much higher than that of port fuel injection vehicles. However, the number of fine particles emitted by vehicles with particle size above 10 nm using port fuel injection technology is about 1.5 times that of particles emitted by vehicles with particle size above 23 nm. The reason for this phenomenon is that the port fuel injection technology will generate more sulfate, small particles of unburned hydrocarbon and other fine particle size. The total amount of particulate matter emitted by sub-vehicles with particle size above 10 nm cannot meet the recommended value of 1 × 1011 #/km proposed by the European Commission League for Low Vehicles Emission (CLOVE). Therefore, it will be a trend for light-duty gasoline vehicles to be equipped with efficient GPF after the next stage of regulation is determined.

SCR is one of the best after treatment technology for de-NOx in automotive diesel engines. However, due to the sea water scrubbing desulfurization in marine diesel engines, the exhaust gas leads to a significant decrease in exhaust gas temperature, so SCR technology for vehicles cannot be directly transferred to marine diesel engines. This work conducted a bench test to test the exhaust emissions of a diesel engine by adding ozone to the exhaust gas under conditions of both low load and idling. The results showed that when the exhaust gas temperature was above180 ℃, NOx increased with a maximum increase of 93.14% due to the ozone decomposition. When the gas temperature was below 100 ℃, ozone oxidized part of NO to NO2. The O3/NO molar ratio had a greater effect on the NOx emissions of diesel engines. As the O3/NO molar ratio was close to 1, the NO oxidation effect was the best and the de-NOx efficiency reached 79.31%. Under low temperature operating conditions, O3 is effective in reducing NOx emissions from the exhaust of marine diesel engines.

Ammonia (NH3), as one of the main components of light-duty vehicle emissions, its emission requirements are most likely to be considered in the next stage of emission regulations, with the increase in vehicle ownership and the tightening of emissions regulations worldwide. Therefore, it is necessary to investigate the characteristics of NH3 emission in automobile exhaust in advance, which is also beneficial to reducing the secondary particulate matter in the atmosphere. In this paper, the emission experiment of a light-duty gasoline vehicle was carried out under different test cycles and ambient temperatures. The emission characteristics of NH3 were analyzed. The representative conditions of NH3 formation and its associated relationship with other emission components are emphasized. The data indicated that the cold starting phase and long-term continuous acceleration are the key representative conditions. The significantly positive correlation between the emissions of NH3 and CO is shown. Here, the emergence of NH3 is accompanied by the large production of CO. But the correlation of NH3 with NOx or THC emissions is not obvious.

Taking the swing arm of the stabilizer bar of the commercial vehicle cab mount as the research direction, the new structure of the body mount is explored and improved by using the topological optimization design method, and the performance of the body mount is compared with that of the original mount. The CAE analysis of the improved rear suspension assembly shows that the fatigue life meets the strength requirements, the mass is reduced by 0.42 kg, and the performance is improved. The results show that the performance of the swing arm of the improved suspension stabilizer has been greatly improved and meets the design requirements.

Commercial vehicles take an important role in transportation system. However, they also produce much pollutant emission and carbon dioxide(CO2) emission. To meet the green transportation target, the commercial vehicle technology roadmap needs to be formulated. For the ICE (Inner Combustion Engine), several new technologies are summarized to meet stricter fuel consumption standards and emission standards, and the energy consumption distribution of traditional fuel vehicles is calculated. For NEV (New Energy Vehicle), a P2 architecture HEV (Hybrid Electric Vehicle) control strategy that can reduce fuel consumption is explained, and the advantages and disadvantages of BEV (Battery Electric Vehicle) and FEV (Fuel Cell Electric Vehicle) are summarized. For ICV (Intelligent and Connected Vehicle), how the technologies of V2X (Vehicle to Everything) and V2V (Vehicle to Vehicle) can effectively reduce emissions is outlined. Finally, the development prospect of commercial vehicles is summarized, and the objectives of carbon emission reduction in the automotive industry are proposed.

This paper proposes a control strategy aiming at the lateral and longitudinal motion performance for the skid steering distributed drive unmanned platform. Firstly, through the mechanic's theory, a seven-degree-of-freedom model of the skid steering vehicle is established, including the body dynamics model, the wheel dynamics model, and the tire model. Secondly, a hierarchical control strategy is designed. The upper layer calculates the expected path as the expected value of wheel speed and yaw rate based on pre-targeting theory and vehicle kinematics reference model; the lower layer control structure is based on model predictive control, the control problem under the platform's lateral and longitudinal composite motion conditions is transformed into the tracking problem of the target wheel speed and the target yaw rate. The torque of the wheel is the output, which realizes the lateral and longitudinal synthetic control of the unmanned platform, and takes into account the optimal control of the wheel slip rate. A simulation model is built in Simulink software, and the corresponding simulation conditions are verified. The results show that the proposed lateral and longitudinal motion control strategy for skid steering unmanned platform is stable and accurate.

In the automatic driving system, the motion control system is an important part, which directly determines whether the vehicle can accurately follow the trajectory. Under conventional working conditions, the existing motion control algorithms can complete the task well, but when the vehicle is driving in complex working conditions, the control accuracy will decrease. This is because the vehicle and road parameters vary greatly in these scenarios, and treating them as constants will cause the calculated values to deviate too much from the demand values. Only by introducing real-time dynamic characteristics of the vehicle can precise control of the vehicle be carried out. In this paper, we propose a vehicle motion control service (VMCS) system based on dynamic states estimation, which takes the MPC algorithm as the core, and uses the real-time estimated vehicle and road state and parameters as the input for the lateral and longitudinal motion control of the vehicle, and carries out simulation experiments and real vehicle experiments. Experimental results show that the proposed VMCS system based on dynamic state estimation can achieve good control accuracy under extreme conditions.

With the fierce competition in the automobile market and the improvement of customers’ personalized needs, especially the changes in appearance, the types of closures have increased and the update cycle has been accelerated. As the meanwhile, due to the shortage of the land resource, the production of automatic flexible welding closures has become the mainstream trend of the current automobile industry. One of the most significant advantages of the closures line is that it allows a variety of models with high flexibility, which would significantly improve the welding line's production efficiency and reduce the investment in labor costs. Welding line solutions with high automation, high flexibility, high standardization, high modularity, and high production capacity can significantly reduce investment and post-maintenance costs, and improve the technical strength and competitive edge of Original Equipment Manufacturer (OEMs). The automatic flexible welding production line for closures welding is studied in this paper and analyzed through the process requirements and product characteristics of the automatic flexible production line, from the planning method of the production line, to automation flexibility, and standardization. It provides a theoretical reference for the practical application of modularized and standardized flexible welding lines for multi-model collinear construction in the later stage.

Taking the rain-detection line in an automobile assembly workshop as an example, this paper briefly introduces the composition, working principle, and design principle of the rain-detection line. Chamber, water treatment system, spray pipeline, water blowing system, exhaust system, conveying system and electric control system are included in the composition. The paper also discusses in detail the calculation method of the key parameters of the rain-detection line which including the calculation of the length of the chamber, the rain intensity and rainfall, the calculation of water treatment system and the calculation of exhaust volume. It has a strong reference significance for the design of the rain test line, and also provides a basis for the further improvement of the vehicle rain detection mode.

Automobile body is a complete body which is processed by welding, riveting or mechanical connection of hundreds of sheet metal stamping parts in the body shop. Due to the large variety of parts and different sizes, pallet with different shapes and specifications usually carry parts of different sizes to the production line. In this paper, a size-adjustable stamping parts transfer pallet is designed. Through the deformation of the pallet, it can meet the transfer of stamping parts of different sizes and ensure a good space utilization rate, thereby saving logistics area and reducing transportation costs.

The whole vehicle drum test-bed is a very important indoor bench test equipment in the process of automobile product development, which provides a solid test basis for the study of automobile performance such as power, economy, comfort and handling stability. The mainstream suppliers in the field of drum control system are all European and American countries, with serious technical blockade; In recent years, the components of its control system are aging seriously, and the failure rate is high, while the research and development cycle of automotive products is shortened, and the requirements for reliable operation of equipment are higher; A large number of electrical components of the existing equipment have been shut down for many years, and the upgrading period is long and the price is expensive; With the continuous development of new technologies of automobile products, the test methods are also constantly adjusted, and it is impossible to cope with simply relying on the transformation and upgrading cycle of the manufacturer. In order to break the technical barrier and master the core technology of key automobile test equipment, it is urgent to develop a set of control system for automobile drum test.

Numerical study on impact damage characteristics of automotive coatings is significant for the material development and structural design of the coatings. A finite element model is proposed for the single-impact damage of automotive coatings, and an in-house explicit finite element program is used to solve the impact problem. The predicted polymer-ply failure patterns and coating delamination area radius are in good agreement with the experimental outcomes, which verifies the capacity of the proposed method in the impact damage analysis of automotive coatings.

A mathematical model of a vehicle climate system can facilitate the development of a vehicle climate control module and reduce costs. In this paper, we present a data-driven method to model the vehicle climate dynamics. The data used for model identification is collected from actual road tests, and a long-short term memory (LSTM) network is applied to sequence modeling. An output projector is added to the LSTM model to isolate the LSTM state and system output. Since the data collected has inconsistent initial working conditions, we design an initial value mapping method to endow the LSTM model with different initial states for different data sequences. Training sequence segmentation and loss weight assignment are introduced to further enhance the training process and improve performance. On the validation set, the mean absolute error (MAE) of predicted temperature from the proposed LSTM model is only 0.4 ℃, while the fit value reaches 97%. Extreme values at the beginning of sequences are suppressed. When the initial value mapping and weight assignment are used, the maximum temperature error is only 3.0 ℃, which is substantially smaller than the errors in other methods. The results indicate the feasibility of using this model to develop and calibrate the vehicle climate control model at low costs.

For the design requirements of air suspension, the failure mode analysis and optimization through suspension system level simulation is necessary. Taking the air suspension equipped with membrane air spring as an example, a 3D air spring FEM model is generated based on the simplified axisymmetric model, finally the air suspension system model is established, reproduce the failure phenomenon based on the suspension model, and thus provides a complete set of simulation analysis method with high precision. On this basis, the relationship between design parameters and structural stability is analyzed, and a structural stability verification method based on bench test is proposed.

The close-coupled selective catalytic reduction (SCR) system integrated with particulate filters (SCRF) has been widely adopted for light/heavy-duty vehicles due to its compactness and faster warm-up performance. However, the performances of the SCRF system are negatively affected by the unwanted growth of deposits formed from the injected urea water solution (UWS), especially under low load engine conditions. This paper has developed a full 3D Computational Fluid Dynamics (CFD) model for a commercial close-coupled SCRF system based on the fluid-solid coupling method. The CFD model was successfully validated by comparing it with experimental results conducted under three diesel engine operating conditions. Our simulation results show that the area and thickness of wall film accumulated in the system are higher under a low exhaust mass flow rate. Under high wall temperature, the deposition rate of UWS is lower than the case under lower wall temperature. Nevertheless, the temperature of wall film is increasingly higher under high wall temperature which leads to the formation of more thermally stable compounds such as CYA and ammelide. Under low wall temperature, urea solid is found to be the main composition generated from the wall film comparing with other chemical compounds. The simulation results could be useful in providing some guidance for the design of SCRF system in terms of deposit reduction.

This paper takes the order noise problem of permanent magnet synchronous motor as the research object, the motor torque ripple and vibration response are evaluated, and whine is confirmed that caused by the excessive harmonic tangential Electromagnetic force. Taking the design parameters such as magnet arrangement and rotor auxiliary slot as the independent variables, reducing the motor torque ripple as goal, by setting up the motor optimization simulation process, establishing high-precision mathematical response surface to simulate motor physical model, finally obtaining the optimal parameter values under the premise of ensuring that the output characteristics are not reduced. The simulation verifies the structural design with excellent NVH performance, this optimization study can effectively improve NVH performance, which is guiding significance for the forward development of the motor.

At present, owing to the different size between the SAE manikins used in seat comfort evaluation and the Chinese anthropometry, and the poor representation and coverage percentile manikin had to actual manikin, it is necessary to establish a new seat comfort manikin model based on the Chinese anthropometry characteristics. In this paper, the principal component analysis was used to reduce the multidimensional data set of the Chinese anthropometry by using eigenvectors and eigenvalues. The goal was to establish a three-dimensional confidence ellipse with 95% confidence, and then select the anthropometry data corresponded to the 26 feature points on the ellipse as boundary manikins. Then established the vehicle seat and boundary manikin by CATIA, carried out the sitting posture simulation analysis, and compared with the verification results of the SAE manikins and the Chinese percentile manikins. The results show that the sitting posture results of the three models are quite different. The established model can more accurately reflect the results of the sitting posture distribution of the Chinese anthropometry data, and can provide a reference for seat design and seat comfort evaluation.

In this paper, an acceleration method based on load-equivalent correlation of body-in-white endurance test is proposed. Taking the BIW durable load target decomposition as the research object, the damage quantity and weight value under various characteristic road conditions are calculated by using the pseudo-damage equivalence theory method. Combined with frequency domain power spectrum density (PSD) analysis, the key characteristic conditions were identified, and an acceleration scheme for BIW endurance test was proposed. Through simulation calculation and road test, the effective correlation of durability failure under this scheme is obtained, and the simulation and test cycles are shortened 6 times and 13.8 times respectively, greatly reducing the development cycle of BIW. This method provides an important engineering reference for the development of durability performance of vehicle and parts.

Because of its remarkable characteristics of vibration reduction and noise reduction, the hydraulic bushing has been more and more used in all kinds of medium and high-end vehicles to improve the ride comfort of the whole vehicle. In this paper, a bench load spectrum acceleration method based on pseudo damage retention is adopted. The vehicle road spectrum test data and the vehicle dynamics model are used for vehicle iteration, so as to obtain the time-domain load spectrum data at the hydraulic bushing, which is used for the bench rapid verification test of the hydraulic bushing.

Aiming at the seam weld fatigue cracking problem of a commercial vehicle suspension, the actual road load data are tested and extracted, and the rigid flexible hybrid multi-body dynamic model of the cab and suspension system is established. The drives of the suspension subsystem are obtained through virtual load iteration, and the mode participation factor and the full field time-domain stress amplitude are obtained. A weld fatigue analysis method based on improved notch stress method is established, and the calculation results of various modeling methods are compared. It is proved that this weld fatigue analysis method has high calculation accuracy and mesh insensitivity which improves the engineering application of notch stress method, and provides a new guiding direction for life prediction and forward design of automobile weld structure.

The performance target setting of passenger car engine cooling system is mainly based on the vehicle thermal balance test condition, at present, the formulation of vehicle thermal balance test conditions is based on the environmental conditions and actual road information of vehicle sales area, engine cooling system developed according to heat balance test conditions, only to ensure that the vehicle in the actual use of the process will not appear engine overheating. Modern vehicle in power, economy, emission, air conditioning comfor, off-road and reliability and other aspects put forward higher requirements, these performances are closely related to the working temperature of the engine and the working state of the accessories of the cooling system, therefore, the engine cooling system performance target setting needs to consider more dimensions. In this paper, the performance data of engine cooling system of more than 60 vehicles in recent 10 years are analyzed, show the development trend of cooling system performance, obtain engine cooling system temperature test data in vehicle performance development test, through the analysis of the test data, the real demand of engine cooling system performance under the condition of the vehicle is judged comprehensively, combined with the big data from the test, some suggestions are put forward from the maximum capacity of engine cooling system, temperature rise rate and temperature control.