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Table of Content

    25 July 2023, Volume 45 Issue 7 Previous Issue    Next Issue
    Research on Motion Planning and Cooperative Control for Autonomous Vehicles with Lane Change Gaming Maneuvers Under the Curved Road
    Cheng Lin, Bowen Wang, Lü Peiyuan, Xinle Gong, Xiao Yu
    2023, 45 (7):  1099-1111.  doi: 10.19562/j.chinasae.qcgc.2023.07.001
    Abstract ( 270 )   HTML ( 20 )   PDF (8385KB) ( 293 )   Save

    When multiple autonomous vehicles perform lane change and merging tasks on structured road, steering and merging actions need to be comprehensively considered to avoid potential accidents. Meanwhile, the changing road curvature and surrounding vehicle speed also increase the difficulty of cooperative control. Focusing on the above issues, this paper proposes a multi-vehicle lane change gaming motion planning and cooperative control method facing variable curvature road. Firstly, a multi-vehicle model in curvature coordinate system is developed to determine the inter-vehicle safety distance and dynamics state. Then, by systematically considering the road curvature variation and surrounding vehicle information, a game-based multi-vehicle lane change motion planning algorithm is proposed, which uses a distributed framework to quickly solve the optimal speed trajectory and lane change timing considering personalized driving. Finally, the road curvature and planning trajectory are identified effectively based on B-sample curve, and an adaptive time-varying model predictive control algorithm is constructed to achieve trajectory tracking. Specifically, the control parameters are updated in real time under the single-step prediction domain to eliminate the control deviations caused by frequently various vehicle speed and curvature. The co-simulation results show that the proposed method can reduce the tracking error by 58% compared to the Stanley method, with reduction of the merging time by 74% compared to the cooperative adaptive cruise control method. Moreover, the computational solution efficiency is only 10% of the centralized method.

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    Autonomous Driving 3D Object Detection Based on Cascade YOLOv7
    Dongyu Zhao, Shuen Zhao
    2023, 45 (7):  1112-1122.  doi: 10.19562/j.chinasae.qcgc.2023.07.002
    Abstract ( 245 )   HTML ( 19 )   PDF (4587KB) ( 391 )   Save

    For the problems of incomplete feature information and excessive point cloud search volume in 3D object detection methods based on image and original point cloud, based on Frustum PointNet structure, a 3D object detection algorithm based on cascade YOLOv7 is proposed by fusing RGB image and point cloud data of autonomous driving surrounding scenes. Firstly, a frustum estimation model based on YOLOv7 is constructed to longitudinally expand the RGB image RoI into 3D space. Then the object point cloud and background point cloud in the frustum are segmented by PointNet ++. Finally, the natural position relationship between objects is explained by using the non-modal 3D box estimation network to output the length, width, height, heading et al. of objects. The test results and ablation experiments on the KITTI public dataset show that compared with the benchmark network, the inference time of cascade YOLOv7 model is shortened by 40 ms?frame-1, with the mean average precision of detection at the moderate, difficulty level increased by 8.77%, 9.81%, respectively.

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    Spatio-temporal Joint Planning Method of Intelligent Vehicles Based on Improved Hybrid A
    Jie Hu, Zhihao Zhang, Ruinan Chen, Ruipeng Chen, Haoyan Liu, Qi Zhu, Hui Chen
    2023, 45 (7):  1123-1133.  doi: 10.19562/j.chinasae.qcgc.2023.07.003
    Abstract ( 289 )   HTML ( 19 )   PDF (4436KB) ( 356 )   Save

    Motion planning is the critical module of trajectory generation in autopilot system. The existing motion planning mostly adopts path-velocity decomposition method, which is easy to fall into trajectory suboptimal in complex dynamic scenarios. In this paper, a spatio-temporal joint motion planning method based on the combination of search and numerical optimization is proposed to solve the drivable trajectory directly. Firstly, the improved hybrid A* is used to search for the initial rough trajectory in the spatio-temporal range. Secondly, a drivable spatio-temporal corridor is constructed based on the initial trajectory, and considering vehicle dynamics and trajectory continuity constraints, the numerical optimization method is used to further smooth the initial trajectory. Finally, two typical complex dynamic scenarios of lane change overtaking and side-vehicle cut-in are selected for simulation test. The results show that the proposed planning method is more flexible and more reasonable than the traditional spatio-temporal decoupling planning method, and has better real-time computing performance.

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    Path Following Method of Intelligent Vehicles Based on Feedback Pure Tracking Method
    Shiju Pan, Jianshi Li, Hua Li, Jingtao Lou, Youchun Xu
    2023, 45 (7):  1134-1144.  doi: 10.19562/j.chinasae.qcgc.2023.07.004
    Abstract ( 120 )   HTML ( 15 )   PDF (3257KB) ( 220 )   Save

    In order to improve the path following accuracy and stability of intelligent vehicles under different speeds and loads, a path following method of intelligent vehicles based on feedback pure tracking is proposed. Firstly, the factors affecting the control effect are analyzed based on the vehicle kinematic model and pure tracking model. Secondly, the forward-looking distance is adjusted dynamically according to the vehicle speed and path curvature, and the lateral error is used as feedback variable to compensate the traditional pure tracking control method. Then, the control parameters are determined through simulation tests, and the influence of the parameters on accuracy and vehicle stability of the path following is analyzed. Finally, a real vehicle test is conducted to verify the control performance of the method in real vehicle environment. The results show that the method has higher path-following accuracy and maintains good adaptability and stability under different speeds and loads.

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    The Method of Probabilistic Multi-modal Expected Trajectory Prediction Based on LSTM
    Zhenhai Gao, Mingxi Bao, Fei Gao, Minghong Tang
    2023, 45 (7):  1145-1152.  doi: 10.19562/j.chinasae.qcgc.2023.07.005
    Abstract ( 164 )   HTML ( 10 )   PDF (2157KB) ( 240 )   Save

    To address the problem that unimodal trajectory prediction cannot adequately represent the future prediction space and solve the inherent uncertainty of trajectory prediction, this paper constructs a driving behavior intention recognition and traffic vehicle expectation trajectory prediction model. The driving behavior intention recognition module identifies the probability of lane keeping, left lane change, right lane change, left acceleration lane change and right acceleration lane change of the predicted vehicle; the traffic vehicle expected trajectory prediction module uses an encoder-decoder architecture to output multiple behaviors and trajectories of the predicted vehicle that may occur within the next 6 seconds. The model is trained, validated and tested with the HighD dataset. The test results show that the multi-modal probability distribution generated by the intention recognition-based expected trajectory prediction model can improve the driving safety of the vehicle, significantly improve the trajectory prediction accuracy compared with other methods, and have obvious advantages in predicting long time domain trajectories.

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    Study on Density Peaks Clustering Algorithm of Vehicle Trajectory Data
    Haobin Jiang, Baosong Lu, Aoxue Li
    2023, 45 (7):  1153-1162.  doi: 10.19562/j.chinasae.qcgc.2023.07.006
    Abstract ( 117 )   HTML ( 1 )   PDF (6577KB) ( 197 )   Save

    With the widespread use of technologies such as the Internet of Things, V2X and smart cities, a large amount of vehicle trajectory data is recorded and retained. The trajectory data can be used to extract relevant information, such as calculating the optimal path, detecting abnormal driving behavior, monitoring urban traffic flow and predicting the next location of vehicles, etc. for which trajectory clustering is one of the key technologies. Density Peaks Clustering (DPC) is a simple and effective density-based clustering algorithm, but the definition of local density in the algorithm does not fully consider the influence of density difference when the density of data samples is unevenly distributed, nor does it have a similarity measure suitable for vehicle driving track. In addition, the algorithm is not effective when encountering relatively high dimensional data. By introducing in k-Nearest Neighbor (KNN) and Principal Component Analysis (PCA) and improving similarity measurement, this paper proposes a density peak clustering algorithm suitable for vehicle running trajectory. Firstly, PCA is used to preprocess high-dimensional data. Then the local density is redefined using the K-nearest neighbor idea. Finally, the influence of Euclidean distance on the allocation strategy is abandoned by redefining the distance function between tracks. The feasibility of the algorithm is proved by experiments on synthetic data sets. At the same time, the effectiveness of the algorithm is also verified by the actual vehicle trajectory data.

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    Gauss Allocation Points Parameterization Parallel Automatic Parking Trajectory Planning for Vehicle Under Multi-Stage Constraints
    Ping Liu, Zhuo Chen, Mingjie Liu, Changhao Piao, Soohyun Jang, Kailin Wan
    2023, 45 (7):  1163-1173.  doi: 10.19562/j.chinasae.qcgc.2023.07.007
    Abstract ( 105 )   HTML ( 6 )   PDF (3903KB) ( 189 )   Save

    A trajectory optimization algorithm combining multi-stage division with non-uniform Gauss collocation parameterization is proposed for vehicle high-precision trajectory planning of parallel parking space. Firstly, a mathematical model of parallel automatic parking is established based on the dynamic equation of vehicle parking and constraint conditions. Then, according to the parking process, it is proposed to divide the parking process into five parking stages including parking start, parking space approaching, parking space entering, parking position adjustment and parking landing and corresponding inequality constraints are established for each stage. Furthermore, multiple stage local Gauss discrete strategy is proposed under pseudo-spectral approach frame to achieve independent allocation in each stage so as to improve the precision and adaptivity of trajectory planning. Finally, simulation tests are carried out on a general car model for long and short parking space to verify the performance of the proposed method in accuracy and adaptivity. The test results show that the proposed method can efficiently obtain smooth parking trajectory and averagely decrease parking time by 2.976 s when compared with the piecewise Gaussian pseudo-spectral method, with 21.7% improvement of parking time performance, which indicates the effectiveness of the proposed algorithm.

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    Lane Change and Obstacle Avoidance Trajectory Planning of Intelligent Vehicle Based on Adaptive Fitting
    Jun Li, Wei Zhou, Shuang Tang
    2023, 45 (7):  1174-1183.  doi: 10.19562/j.chinasae.qcgc.2023.07.008
    Abstract ( 135 )   HTML ( 8 )   PDF (2681KB) ( 181 )   Save

    In this paper, the predictive trajectory planning of intelligent vehicles of lanes changing and obstacle avoidance in dynamic environment is studied. Firstly, the coordinate system and dynamic lane change and obstacle avoidance scenarios are defined, to determine the driving constraints of vehicle lane change and obstacle avoidance trajectory planning, and the controlled vehicle and obstacle vehicle models are built. Then, an adaptive piecewise Bezier curve-fitting algorithm is designed to fit the discrete point sequence of the lane change and obstacle avoidance trajectory planning. Further, the model predictive control algorithm is used to design the trajectory planning method for intelligent vehicles for lane changing and obstacles avoidance. Finally, the prediction trajectory planning method of the intelligent vehicle lane change and obstacle avoidance model in a dynamic environment is simulated and analyzed. The results show that the trajectory planning scheme of lane change and obstacle avoidance in this paper can enable the controlled vehicle to complete obstacle avoidance and maintain a stable state in dynamic environment. The adaptive piecewise Bezier curve fitting algorithm designed in this paper has a continuous and smooth fitting trajectory, and the fitting residual between the discrete point sequence provided by the lane change and obstacle avoidance trajectory planning and the corresponding point of the Bezier curve is kept within the set threshold.

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    An Intrusion Detection System for In-vehicle CAN Network Based on Sample Entropy
    Yingxiang Cui, Youtong Zhang, Hongqian Wei
    2023, 45 (7):  1184-1191.  doi: 10.19562/j.chinasae.qcgc.2023.07.009
    Abstract ( 106 )   HTML ( 8 )   PDF (3185KB) ( 132 )   Save

    The intelligent and unmanned development of automobiles has increased the dependence on the automobile bus network, such as the real-time power control of the automobile, the automobile steering control, etc., which require the automobile CAN network as the carrier of information transmission. However, unlike the industrial Internet, which has sound mechanism of information identification and identity authentication, the on-board CAN network lacks sufficient security protection measures and is easy to be invaded by criminals. Therefore, in order to enhance the secure communication capability of the vehicle CAN network, an intrusion detection system based on sample entropy is proposed in this paper. Specifically, the sample entropy test set is constructed by sampling the bus data of the car in real time, and the sample entropy value is counted by using the sample entropy calculation method, the sudden change of which is observed to determine whether there is an attack at this moment. In addition, this paper uses the actual automotive ECU to conduct a hardware-in-the-loop test to verify the detection capabilities of the proposed method for DOS attacks, fuzzy attacks, and bus-off attacks. The test results show that DOS attack, fuzzy attack, and bus-off attack will make the stable sample entropy value appear non-conductive point, which can be used as an abnormal sign of communication data to determine the intrusion behavior of CAN network. In addition, the online detection of embedded devices also verifies the real-time execution ability of this method on actual ECUs.

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    Performance Study of Diesel Natural Gas Hydrogen Three Fuel Engine Based on RCCI
    Wenjin Qin, Jingjing Shi, Lihui Xu, Zhendong Zhang, Yuedong Sun
    2023, 45 (7):  1192-1199.  doi: 10.19562/j.chinasae.qcgc.2023.07.010
    Abstract ( 82 )   HTML ( 3 )   PDF (2190KB) ( 228 )   Save

    With the increasingly serious problems of environmental pollution and energy consumption, the search for clean alternative fuels and new combustion technologies has gradually become the focus of engine research. In this paper, a diesel natural gas hydrogen three fuel RCCI internal combustion engine is numerically simulated, and the effect of different hydrogen ratios on the engine performance is discussed. The results show that with the increase of hydrogen addition ratio, the combustion rate of the in cylinder mixture is significantly increased, the peak pressure in the cylinder gradually increases, and the phase of the peak value is advanced, with the average temperature in the cylinder increased. Meanwhile, the indicated thermal efficiency of the engine increases, and the equivalent indicated fuel consumption rate decreases, which improves the fuel economy of the engine. Because the pressure rise rate and the sound intensity are within the allowable range, the engine operates well. In addition, the exhaust gas temperature decreases with the increase of hydrogen addition ratio, and the exhaust gas energy shows a downward trend. In general, appropriate increase of the hydrogen addition proportion is beneficial to improve the overall performance of the engine.

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    Active Suspension Control Based on Interacting Multiple Model Kalman Filter
    Xiao Wu, Wenku Shi, Zhiyong Chen
    2023, 45 (7):  1200-1211.  doi: 10.19562/j.chinasae.qcgc.2023.07.011
    Abstract ( 140 )   HTML ( 4 )   PDF (4692KB) ( 238 )   Save

    For the problem that it is difficult for fixed state observer to ensure the accuracy of road adaptive suspension state observation, the suspension state observer and controller is established on the basis of interactive multi-model Kalman filter (IMMKF). Firstly, the road adaptive active suspension system is established based on the LQG algorithm and fuzzy control algorithm. Combined with harmonic superposition method, the A-B-D-C grade spatial domain road roughness model is generated as the input of the simulation system. Secondly, three kinds of IMMKF suspension state observer and controller are established taking the optimal LQG model of all grades of road as the sub-models. The simulation comparison shows that the observation accuracy of the 14-model IMMKF suspension state observer can be improved by 98.17% maximumly compared with the ordinary Kalman filter, and can be used to identify road grade, and the body acceleration of the adaptive active suspension controller based on the 14-model IMMKF is reduced by 75.99% compared with the passive suspension and 47.16% compared with the ordinary LQG active suspension, which verifies the superiority of the model.

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    Research on Estimation Strategy of Vehicle Driving State Based on Tire Piecewise Affine Identification Model
    Xiaoqiang Sun, Yulin Wang, Weiwei Hu, Yingfeng Cai, Long Chen, Wong Pak Kin
    2023, 45 (7):  1212-1221.  doi: 10.19562/j.chinasae.qcgc.2023.07.012
    Abstract ( 70 )   HTML ( 2 )   PDF (4543KB) ( 183 )   Save

    For accurate state estimation in the process of vehicle lateral motion, an estimation algorithm considering the tire nonlinear cornering mechanical characteristics is proposed. In order to accurately reflect the evolution law of vehicle lateral dynamics under special driving conditions, a vehicle dynamics model considering the tire nonlinear cornering mechanical characteristics is established by using the piecewise affine identification method, and then the piecewise affine model of vehicle lateral dynamics is constructed. On this basis, a "multi-mode switching" state estimation strategy for the piecewise affine model of the system is designed based on the strong tracking square root cubature Kalman filter algorithm to maintain good state estimation accuracy when the system state changes suddenly. Based on CarSim and MATLAB/Simulink, a Co-Simulation platform for vehicle driving state estimation performance is established. By setting up two typical working conditions, the state estimation effect of vehicle yaw rate and sideslip angle is verified. The results show that the proposed estimation algorithm can achieve high-precision estimation of vehicle driving state under special driving conditions.

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    Tire-Road Friction Estimation Method Based on Image Recognition and Dynamics Fusion
    Lei Zhang, Keren Guan, Xiaolin Ding, Pengyu Guo, Zhenpo Wang, Fengchun Sun
    2023, 45 (7):  1222-1234.  doi: 10.19562/j.chinasae.qcgc.2023.07.013
    Abstract ( 171 )   HTML ( 10 )   PDF (6317KB) ( 255 )   Save

    Accurate estimation of tire-road friction is a prerequisite for vehicle active safety control. Firstly, a single-wheel dynamics model is established, and precise estimation of the longitudinal tire force is realized using the Kalman filter. Then a particle filter (PF)-based tire-road friction estimator is developed based on the Magic Formula tire model. Secondly, a forward road adhesion coefficient prediction method based on image recognition is proposed. The DeeplabV3+, semantic segmentation network and the MobilNetV2 lightweight convolutional neural network are used for road segmentation and classification, based on which the tire-road friction is obtained through table look-up. Finally, the spatiotemporal synchronization method and fusion mechanism of dynamics and image recognition are established to realize effective correlation and reliable fusion of the two estimation methods. The Carsim-Simulink co-simulation shows that the proposed estimation method based on image recognition and dynamics fusion can efficiently improve the tire-road friction estimation accuracy.

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    Research on the Estimation of Vehicle Speed Under Low-Speed Conditions Based on Multi-sensor Information
    Zhenfeng Pu, Liang Tang, Wenbin Shangguan, Weiwei Wang, Kaihong Jiang
    2023, 45 (7):  1235-1243.  doi: 10.19562/j.chinasae.qcgc.2023.07.014
    Abstract ( 141 )   HTML ( 10 )   PDF (1896KB) ( 236 )   Save

    To solve the problem of low measurement accuracy and long update period of wheel speed sensor under low-speed conditions, a method for estimating low-speed of an electric vehicle is proposed based on multiple sensor signals by using the existing sensors located at chassis. The speed estimation models based on multi-wheel speed pulse signal (model I) and motor speed signal (model II) is established respectively to accurately estimate the vehicle speed. When estimating the wheel speed, model I can effectively avoid noise interference, but its update period is longer at very low speed. In contrast model II estimates the wheel speed information with a short update period and high accuracy, but it can’t overcome the impact interference caused by backlash in the drive train. To take into full play of the advantages of the two estimation models, an interactive multi-model fusion algorithm is used in this paper to fuse the output of the two models. The accuracy and reliability of the proposed low-speed estimation algorithm under different roads are validated by actual vehicle comparison experiments. The results show that compared with the traditional algorithm, the proposed method in this paper has higher accuracy and better real-time performance at low-speed conditions.

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    An Experimental Study on the Effect of Varnish on the Thermal Conductivity of Armature
    Zhaozong Li, Chengning Zhang, Hengliang Zhang, Shuo Zhang
    2023, 45 (7):  1244-1253.  doi: 10.19562/j.chinasae.qcgc.2023.07.015
    Abstract ( 60 )   HTML ( 1 )   PDF (4467KB) ( 93 )   Save

    In order to meet the demand of various driving structures, electric motors for EVs usually have to make a choice between high speed and high torque. To optimize the high efficiency area of EV motors, multiple armature structures are applied to the motors. Compared with armatures used in static electric facilities, the most notable feature of EV motor armature is that they generally need to be varnished with non-metallic materials. However, few models can reasonably predict the axial thermal conductivity of armatures with the casting process. In this paper, 9 common armature structures of motor are studied, including hairpin winding, enameled wire, transposition wire, circular litz wire and rectangular litz wire. A test bench for measuring the axial thermal conductivity is established at first, and a mathematical method for compensating the tolerance of the experimental bench is proposed. Then, the axial thermal conductivity differences of 9 armatures before and after varnishing are tested and compared. Finally, based on the machining methods and experimental results of various kinds of armatures, the mathematical model and empirical formula of axial thermal conductivity for "Parallel Winding " and "Twisted Winding" armatures are presented respectively, considering the influence of varnish process.

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    High-Temperature Transient Thermal Damage Simulation and Optimization Research of a Four Wheel Drive SUV Vehicle
    Xiayi Yuan, Lu Xiao
    2023, 45 (7):  1254-1262.  doi: 10.19562/j.chinasae.qcgc.2023.07.016
    Abstract ( 73 )   HTML ( 4 )   PDF (5603KB) ( 95 )   Save

    When the vehicle idles or stalls after continuous driving under high load conditions in a high temperature environment, the temperature of some components located in the engine compartment and the underbody may rise instantaneously, resulting in thermal damage to the components. Due to the 4WD drive system and exhaust system are arranged in parallel in the middle channel of the underbody, which further compresses the distance between the exhaust pipe and the surrounding components that need temperature protection, increasing the risk of thermal damage to the components. In this paper, the transient CFD simulation method is used to simulate the development process of thermal damage of components under idling condition after the vehicle running under high load in high temperature environment. The environmental wind tunnel test results of the vehicle show that the CFD simulation error of high temperature transient thermal damage is basically within 10%. Separating the convection heat transfer power and radiation heat transfer power that cause the temperature of the component to change can accurately determine the cause of the high temperature of the component, which is beneficial to quickly find out the optimization schemes.

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    Fatigue Simulation and Experimental Study of Super-size Integral Die Casting Aluminum Alloy Rear End Body
    Weihe Zeng, Ligang Gou, Yu Luo, Jun Zhang, Huihong Liao
    2023, 45 (7):  1263-1275.  doi: 10.19562/j.chinasae.qcgc.2023.07.017
    Abstract ( 120 )   HTML ( 8 )   PDF (7302KB) ( 346 )   Save

    For the durability development problem of an vehicle with super-size integral die casing aluminum alloy rear end body, the E-N data of the cast aluminum alloy for the die casting body is tested and the key parameters of die-casting alloy E-N curve are obtained by fitting the experimental measured data of fatigue samples. Finite element model of Trim body is built and the dynamic stress response of the die casting body is calculated based on the modal transient method. Rain flow statistics is carried out to the stress time history response signal. Combined with the measured material E-N curve and Miner’s damage accumulation principle., the body fatigue damage of initial design and optimized design are analyzed and compared. Finally, the optimized integral die casting part is loaded into the vehicle for the four-column strengthening durability test. The investigation results show that the E-N relation curve of die casting aluminum alloy can be described by Manson-Coffin-Basquin equation. Compared with the original design, the maximum damage of the improved integrated die casting aluminum alloy body is reduced from 2.67 to 0.32, and the risk of fatigue cracking is eliminated. No cracks are found in the body after the reinforced four-column endurance experiment verification. The research results can provide a reference for the development of integral die-cast aluminum alloy body to achieve the goal of vehicle durability properties.

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    Dynamic Response of Occupant's Neck During Rolling of a Vehicle
    Yaoyu Fu, Erzhen Zhou, Ruiyang Ding, Yunbo Zhou, Tiaoqi Fu, Ming Zhang
    2023, 45 (7):  1276-1285.  doi: 10.19562/j.chinasae.qcgc.2023.07.018
    Abstract ( 92 )   HTML ( 3 )   PDF (4349KB) ( 113 )   Save

    In order to study the type of neck sports injury of the passenger in the front passenger seat of a vehicle during the rollover process, LS-Dyna software is used to simulate the slope rollover, platform vehicle rollover and spiral rollover process, analyze the neck force and moment response of the passenger during the rollover process, and judge the neck injury state of the passenger. Based on the neck force and moment, a hypothesis is established to judge the neck posture of the occupant at a certain moment, which can reproduce the motion posture of the dummy without recording the dummy’s motion in the test. The slope rollover test of a vehicle is carried out to verify the accuracy of the slope rollover simulation results. The analysis results show that the neck movement state of the passenger in the process of rollover can be accurately judged by combining the response of neck force and neck moment, and it is concluded that the contact collision between the head of the passenger and the vehicle body has an important impact on the neck injury of the passenger in the process of rollover.

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    Multi-objective Optimization Design of Induction Groove for Aluminum/CFRP Hybrid Tube Under Multi-angle Compression Condition
    Dengfeng Wang, Chunda Lu, Hongyu Liang
    2023, 45 (7):  1286-1298.  doi: 10.19562/j.chinasae.qcgc.2023.07.019
    Abstract ( 75 )   HTML ( 1 )   PDF (4690KB) ( 141 )   Save

    Oblique impact is common in vehicle accidents, and a reasonable inductive structure of energy absorbing components is crucial for comprehensive crashworthiness. In this paper, the design method of inductive structure based on aluminum/CFRP hybrid tube is studied. Firstly, a high-precision finite element model of aluminum/CFRP hybrid tube is established, which is verified by experiments. Then, based on the multi-angle compression conditions, the effect of the location parameter, number parameter, shape parameter and size parameter of the induction groove on the crashworthiness of aluminum/CFRP hybrid tube is studied respectively. The results show that the location parameter has the greatest influence on the comprehensive crashworthiness. Setting a rectangular induction groove in the upper part of the hybrid tube can largely reduce the peak force and enhance the energy absorption stability. Finally, based on the NSGA-II algorithm, the multi-objective optimization design of the induction groove is carried out. The optimization results show that the peak force of the hybrid tude is reduced by 35.5% on the premise of ensuring the comprehensive energy absorption under different weight schemes, effectively solving the problem of balancing high energy absorption and low peak crushing force. The research results provide important guidance in the design and application of energy absorbing components.

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