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Table of Content

    25 October 2021, Volume 43 Issue 10 Previous Issue    Next Issue
    A Fast Multiple Maneuvering Vehicle Tracking Algorithm Based on Half Suppressed Fuzzy C⁃means Clustering
    Junhui Zhang,Zongjie Fu,Xiaoman Guo,Qing Li,Dapeng Chen,Ye Zhao
    2021, 43 (10):  1419-1426.  doi: 10.19562/j.chinasae.qcgc.2021.10.001
    Abstract ( 540 )   HTML ( 39 )   PDF (2152KB) ( 524 )   Save

    In order to improve the real-time performance and reliability of multi-target data association in complex traffic scenarios, a fast multi-target vehicle tracking algorithm based on half suppressed fuzzy c-means clustering (HS-FCM) is thus proposed in this article. Firstly, the multi-target vehicle-tracking problem is described mathematically, and the spatial mapping relationship between the camera pixel coordinate system and the world coordinate system is established. Secondly, the fuzzy clustering approach based on fuzzy theory is employed to solve the plot-track association problem. The probability of a feasible joint event in the joint probability data association (JPDA) algorithm is indirectly calculated by solving the fuzzy membership function defined by the distance between a sample and its cluster center. The multi-objective state is filtered and estimated by the probability weighted fusion method. Thirdly, in the dense vehicle environment the measurement update is suppressed by adjusting Kalman gain reasonably to solve the problem of short-term target losing. The real vehicle test and simulation results validate the feasibility and effectiveness of the proposed fast multi-vehicle tracking algorithm.

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    Fine⁃grained Vehicle Detection and Classification Model for Video Structuring Description
    Jian Shi,Qian Cheng,Lisheng Jin,Yaoguang Hu,Xiaobei Jiang,Baicang Guo,Wuhong Wang
    2021, 43 (10):  1427-1434.  doi: 10.19562/j.chinasae.qcgc.2021.10.002
    Abstract ( 333 )   HTML ( 16 )   PDF (2611KB) ( 301 )   Save

    In order to solve the problem of limited understanding of complex traffic scenes in driverless environment perception technology, this paper proposes a roadside-oriented video structured description framework, which can enrich the fine-grained information of different targets in traffic scenes and improve the understanding ability of complex traffic scenes. For the proposed framework, this paper provides an engineering fine-grained vehicle detection and classification model. The YOLOv4 algorithm is optimized by channel pruning strategy, and the volume of the compressed model, YOLOv4-Pruned, is reduced by about 60% compared with the original model under the condition that mAP is almost unchanged. A vehicle classification method with 16 types and 12 colors is designed, which can effectively cover all vehicles in the current traffic scene. And the classification accuracy of the test set can reach 93%. The fine-grained vehicle detection and classification model designed in this paper is stable at 23FPS under 1920 × 1080 pixel input, NVIDIA Geforce RTX 2080ti, and the unquantified model is stable at 13FPS under Hisilicon-Hi3516DV300.

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    Vehicle Target Oriented Bidirectional Matching Handover Method for Multi Camera on Roadside
    Ming Chen,Yimin Wu,Bolin Gao,Kaiyuan Zheng
    2021, 43 (10):  1435-1441.  doi: 10.19562/j.chinasae.qcgc.2021.10.003
    Abstract ( 609 )   HTML ( 12 )   PDF (1490KB) ( 324 )   Save

    Because of the high field of view angle and wide detection range, roadside sensor is conducive to observe the spatial?temporal relationship and movement trend of targets, and becomes an important sensing means to support the vehicle road cloud integration system. However, the current roadside sensor faces the challenge that it is difficult to continuously track the target motion across the sensing domain. In order to solve the problem of target handover between cross view cameras, a bi?directional matching target handover method is proposed for roadside sensing overlapped field of vision. The transformation relationship between cameras is established to project the vehicle target in the overlapped domain, and the matching constraint mechanism is designed to solve the problem of matching conflict. The bidirectional matching strategy is designed based on the bidirectional projection of the target, and the handover result is output according to the matching matrix identifier and color similarity. The roadside experimental data show that the proposed method can be effectively applied to typical urban road traffic scenes. Compared with the one?way matching method, it reduces the missing matching by 22.22% and the false matching by 28.57% for road scenes; The missing matching and false matching of intersection scenes are reduced by 28.89% and 44.00%, respectively, which has good accuracy and reliability.

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    Fast Energy⁃saving Speed Planning Through Multi Signal Intersections of Intelligent Vehicles
    Jianghao Leng,Chao Sun,Bing Lu
    2021, 43 (10):  1442-1447.  doi: 10.19562/j.chinasae.qcgc.2021.10.004
    Abstract ( 431 )   HTML ( 22 )   PDF (1666KB) ( 399 )   Save

    The existing energy?saving speed planning method of intelligent vehicles for complex scenes at multi signal intersections is usually with big computational burden that cannot be implemented in real-time. This paper proposes an optimized intelligent vehicle energy?saving speed planning method combining dynamic programming and the interior point method, which can rapidly calculate the road energy?saving reference speed based on the vehicle fuel consumption model and the traffic light information, and realize real?time application. Firstly, in this paper, the vehicle fuel consumption model and the signal phase and time mathematical model are established. A weighted orientation graph based on energy consumption per unit distance at cruise speed is constructed by sampling the arrival time at each intersection. The weighted orientation graph is solved via dynamic programming to obtain the optimal period of green light passing phase. Then, taking the optimal green light passing phase as the constraint, the optimal control problem is formulated and transformed into a nonlinear optimization problem, which is solved via the interior point method. To accelerate convergence speed, the initial guess of the interior point method is set to the solution of the weighted orientation graph solved by dynamic programming. Finally, simulation is carried out for evaluation. The results show that: (1) the proposed method can reduce energy consumption by over 30% compared with the improved intelligent driver model; (2) the initial guess close to optimal solution calculated by dynamic programming improves computational efficiency by more than 40%, compared with the rule?based iterative initial guess generation method.

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    Experimental Study on the Effects of Thermal Insulation Layers on the Propagation Characteristics of Thermal Runaway in Lithium⁃ion Battery Module
    Runze Chang,Bin Zheng,Xuning Feng,Chengshan Xu,Huaibin Wang,Liduo Chen,Youtang Wang
    2021, 43 (10):  1448-1456.  doi: 10.19562/j.chinasae.qcgc.2021.10.005
    Abstract ( 261 )   HTML ( 13 )   PDF (6637KB) ( 455 )   Save

    In this paper, an experimental study on the effects of different types of heat insulation layer on the propagation characteristics of thermal runaway in battery modules is conducted. The results show that heat insulation layer can extend the heat spread time of battery module, prevent the fire caused by valve eruption in battery and lower the peak temperature in the thermal runaway of battery module. Among them, the thermal runaway propagation effect of the insulation layer of preoxidized fibers aerogel has the best effect in suppressing the propagation of thermal runaway. Its total propagation time of thermal runaway is 138% longer than that of ceramic aerogel, and 279% longer than that of nano-glass fiber.

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    Multi⁃objective Optimization of Traction Battery Pack Based on EGO Strategy with Additive Sample Points
    Puyi Wang,Yingchun Bai,Cheng Lin,Zhenjiang Wu,Baohua Wang
    2021, 43 (10):  1457-1465.  doi: 10.19562/j.chinasae.qcgc.2021.10.006
    Abstract ( 235 )   HTML ( 8 )   PDF (1791KB) ( 189 )   Save

    For the lightweighting of battery pack and increasing its modal frequency, a multi-objective optimization scheme based on efficient global optimization (EGO) strategy with additive sample points is proposed. Firstly, by using the design of experiment and Pareto rule, the effects of design variables on the optimization objectives are analyzed, and the variables having more significant influences on the mass and 1st-order modal frequency of battery pack are chosen to be optimized so as to reduce the problem-solving difficulty. Then, multi-objective particle swarm optimization (MOPSO) algorithm is adopted assisted with Kriging surrogate model to solve the optimization problem, and the EGO strategy with additive sample points is employed to get the new design points and samples respectively, with the surrogate model updated until the optimization procedure converges. Finally, the test functions are utilized to verify the effectiveness of the scheme proposed, which is then applied to the multi-objective optimization of battery pack. The results show the scheme is efficient and feasible, with which the mass of battery pack reduces by 4.89 kg while maintaining a higher 1st order modal frequency.

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    Study on Control Strategy for Anode and Cathode Pressures in Proton Exchange Membrane Fuel Cell
    Jiujian Chang,Xiaolin Wang,Jianping Fang,Dilin Xie,Chen Wang
    2021, 43 (10):  1466-1471.  doi: 10.19562/j.chinasae.qcgc.2021.10.007
    Abstract ( 244 )   HTML ( 14 )   PDF (1552KB) ( 260 )   Save

    In order to extend the service life of the proton exchange membrane fuel cell (PEMFC), a model for PEMFC including its cathode and anode supply system is established in this paper based on an analysis on the principle of the pressure regulation of PEMFC. A control strategy for both cathode and anode pressures is designed and the flow control components covering air compressor, throttle valve and hydrogen injection valve are jointly controlled according to the pressure difference between cathode and anode. The results of hardware-in-the-loop simulation show that with the joint control strategy for cathode and anode pressures, the cathode oxygen supply can stably respond to a large sudden change in load. The anode realizes the decoupling of pressure regulation and fuel supply, and the anode pressure can quickly change to follow the cathode pressure. The pressure difference between cathode and anode can be maintained at a very low value even under complex working conditions, significantly extending the service life of proton exchange membrane.

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    Estimation of Battery State⁃of⁃Health Using Particle Swarm Optimization with Gauss Process Regression
    Lin Chen,Bohao Liu,Yunhui Ding,Shuxiao Wu,Zhe Feng,Haihong Pan
    2021, 43 (10):  1472-1478.  doi: 10.19562/j.chinasae.qcgc.2021.10.008
    Abstract ( 240 )   HTML ( 16 )   PDF (1129KB) ( 331 )   Save

    In order to accurately estimate the state of health (SOH) of lithium?ion battery in the process of nonlinear degradation, an AMPSO?GPR algorithm is proposed by the fusion of adaptive mutation particle swarm optimizer (AMPSO) with gaussian process regression (GPR). Firstly, the increment of ohmic internal resistance and the sample entropy of voltage are extracted as degradation characterization indicators. Then AMPSO is introduced to optimize the hyperparameters of GPR kernel function, an SOH estimation framework based on AMPSO?GPR is constructed, and the degradation characterization indicators are extracted to perform SOH estimation. Finally, by comparing the results of SOH estimation using AMPSO?GPR with different kernel functions, the optimal kernel function is obtained. The results of experiment indicate that the AMPSO?GPR algorithm can effectively estimate the SOH of battery with a maximum absolute estimation error not more than 2.08%.

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    Experimental Research on Key Influencing Factors of Regenerative Characteristics of Silicon Carbide CDPF
    Qing Li,Guisheng Chen,Ying Luo,Ru He,Han Zhang,Weijie Shi
    2021, 43 (10):  1479-1487.  doi: 10.19562/j.chinasae.qcgc.2021.10.009
    Abstract ( 152 )   HTML ( 7 )   PDF (5872KB) ( 192 )   Save

    Based on the D30 TCI diesel engine, a test bench for the National 6 after-treatment system is built to carry out the CDPF passive regeneration equilibrium point temperature test under different soot loads so as to study the influence of the inlet temperature on the passive regeneration of the CDPF. The active regeneration characteristics of the CDPF under the engine DTI condition are explored and its influence on the capture characteristics of the carrier is evaluated. The results show that the carbon loading has no significant effect on the temperature at the equilibrium point of CDPF passive regeneration and the increase of carbon loading can improve the uniformity of the internal temperature of the carrier and accelerate the reaction rate of CDPF passive regeneration. The inlet temperature has significant effect on the passive regeneration of CDPF. When the temperature is increased from 325 to 360 ℃, the regeneration efficiency reaches 94%, and the regeneration rate is 56 g/h, which is increased by 1 and 18 times respectively. Under DTI conditions, during CDPF active regeneration, the internal temperature of the carrier will appear "peak". The internal temperature and temperature rise rate reach the peak at the center of the rear section. There is no obvious impact on the PM capture efficiency of CDPF after multiple DTI active regeneration, but the PN capture efficiency will decrease; and the four exhaust pollutants (HC, CO, PM, PN) in WHTC test cycle all meet the National 6 emission regulations and limits.

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    Improvement of One⁃step Rollover Collision Algorithm by Optimizations of Integration and Iteration Modes
    Yisong Chen,Zitong Chen,Tong Wang,Yongtao Liu,Geng Luo
    2021, 43 (10):  1488-1496.  doi: 10.19562/j.chinasae.qcgc.2021.10.010
    Abstract ( 127 )   HTML ( 2 )   PDF (2340KB) ( 158 )   Save

    In view of the poor calculation accuracy and low efficiency of the initial algorithm of one-step rollover collision due to the tremendous computing efforts in in-plane four-point integration of Mindlin shell element, the irrational iteration mode of generalized unbalanced force and being prone to shear lock, the initial algorithm is optimized from two aspects in this paper. For the optimization of element integration point mode, both in-plane reduced integration and partial reduced integration are introduced, and three integration schemes, i.e. five point-, seven point- and nine point integrations are adopted along the direction of element thickness, which is then matched with in-plane integration. For the iteration mode optimization of generalized unbalanced forces, the separate weighting factor is defined for force and moment, respectively, to calculate the “2” norm of unbalanced force, and by means of calculation time-weighting factor ratio curve, the reasonable weighting factors for both force and moment are determined. Finally, the typical segment of a coach body is chosen as real calculation example, the results of improved algorithm, initial algorithm, LS-DYNA analysis and rollover test are compared, verifying the effectiveness of the improved scheme proposed.

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    Research on Identification and Evaluation Methods of Vehicle Crash Aggressiveness Based on MPDB Test
    Haitao Zhu,Zhendong Sun,Jialin Yang,Zhigang Huang
    2021, 43 (10):  1497-1503.  doi: 10.19562/j.chinasae.qcgc.2021.10.011
    Abstract ( 194 )   HTML ( 5 )   PDF (4115KB) ( 165 )   Save

    In view of that in Euro NCAP 2020, ODB test is replaced by MPDB test, and in the evaluation method of vehicle crash compatibility newly introduced, the transmission path and acting height of crash force cannot be monitored and identified, and the overall stiffness of vehicle frontend cannot be quantitatively evaluated, an evaluation strategy for the aggressiveness of vehicle frontend structure is proposed with consideration of the influencing factors of crash compatibility reflected by traffic accidents. Through the analysis on the energy absorbing theory of MPDB barrier, the evaluation regions of aluminum honeycomb are redivided, and so the corresponding evaluation indicator is put forward for each evaluation region, the monitoring and identifying method for the transmission path of crash force are obtained and the evaluation indicator and its implementation method of barrier energy absorption ratio correlated to the overall stiffness of vehicle are given.

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    Vehicle Safety Performance Improvement Based on Coupling Between Crash Waveform and Restraint System
    Hongbin Tang,Ledan Liu,Junyuan Zhang
    2021, 43 (10):  1504-1512.  doi: 10.19562/j.chinasae.qcgc.2021.10.012
    Abstract ( 129 )   HTML ( 4 )   PDF (2665KB) ( 170 )   Save

    In the process of vehicle frontal crash, the coupling effect between body structures and restraint system directly affects occupant injuries. By combining theory and experience and using the evaluation method of the coupling relationship between crash waveform and restraint system, an analysis on the coupling relationship between the body structure and restraint system of a B-class passenger car is conducted, with body energy-absorbing structure and occupant restraint system modified. Final results indicate that the frontal crash star rating of that car is raised from three stars to five stars, effectively enhancing the safety performance of the vehicle.

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    Forming Technologies and Crashworthiness Analysis of Automotive Tailor Welded B-pillar
    Binbing Huang,Shaopeng Li,Shucai Xu
    2021, 43 (10):  1513-1518.  doi: 10.19562/j.chinasae.qcgc.2021.10.013
    Abstract ( 238 )   HTML ( 3 )   PDF (2657KB) ( 202 )   Save

    In order to enhance the crashworthiness of the B-pillar of a new energy vehicle, a tailor welded B-pillar structure is adopted, and starting with forming process and structural crashworthiness, the structure of tailor welded B-pillar is modified based on Dynaform forming simulation and LS-dyna collision simulation. In stamping forming numerical simulation, the influences of forming limit, thickness change and strain state of tailor welded B-pillar on wrinkling and cracking in forming process are studied. By controlling process parameters and modifying die structure, the occurrences of such defects are avoided. As a result of modification, on the premise of meeting the side impact regulations, the mass of B-pillar reduces by 17.5%, its maximum intrusion and maximum acceleration in side impact reduce by 14.38% and 19.3% respectively.

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    Research on the Construction Method of Urban Compound Driving Cycle with Curved Road Information
    Wen Sun,Juncai Rong,Junnian Wang,Jia Xu,Lü Siwen,Lili Liu
    2021, 43 (10):  1519-1527.  doi: 10.19562/j.chinasae.qcgc.2021.10.014
    Abstract ( 142 )   HTML ( 12 )   PDF (1938KB) ( 236 )   Save

    In view of the lack of the condition of driving on curve in urban driving cycle for the evaluation of vehicle energy consumption, a construction method of driving on curve condition in cities is formulated based on short trip analysis. The processing method of optimized data is used to obtain accurate curved road condition data with curved road divided into segments. Principal component analysis is used to compress the experimental data with its dimension lowered. K?means clustering algorithm is utilized to classify all the curved road segments for obtaining the representative driving on curve conditions and the representative curved road segments are added into the traditional typical urban comprehensive driving cycle based on the degree of similarity, so as to obtain an urban compound driving cycle covering curved road information. The results indicate that the urban compound driving cycle with the information of driving on curve condition can better embody the real driving characteristics of vehicles in cities than traditional vehicle driving cycle.

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    Research on Strong Coupling Wireless Charging System Based on LCC/N Magnetic Integrated Compensation Network
    Zhimeng Liu,Chengxuan Tao,Lifang Wang,Yuwang Zhang,Shufan Li
    2021, 43 (10):  1528-1535.  doi: 10.19562/j.chinasae.qcgc.2021.10.015
    Abstract ( 134 )   HTML ( 3 )   PDF (3253KB) ( 281 )   Save

    In view of the complex circuit on the receiving side and the large volume of compensation inductance on the transmitting side of wireless charging system (WCS), a strong coupling WCS using LCC/N magnetic integrated compensation network and for being used in short distance condition is proposed in this paper. The LCC/N magnetic integrated topology combines both the advantages of no compensation circuit at receiving side and compensation inductor magnetic integration at transmitting side to make the WCS more compact and improve its coil offset performance. Firstly, the model for WCS is established with consideration of the cross-coupling relationship between the LCC/N magnetic integrated topology and the receiver coil. Then, the output power, transmission efficiency and zero-voltage-switch characteristics of the WCS with LCC/N magnetic integrated topology are analyzed under the condition of different loads and offsets. Finally, a 500 W experimental platform is built to verify the results of above analysis. The results show that when the coil offset is along y direction, the output power of system with LCC/N magnetic integration topology is higher than that of system with traditional non-magnetic integrated topology, thus its offset performance is improved. In addition, the adoption of LCC / N magnetic integrated topology can also achieve the adjustment of output power by changing the non-resonant compensation capacitor in primary side, with its highest efficiency reaching 95.8% and 94.5% respectively under the condition of with and without offset.

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    Influence of Groove Area on the Clutch Friction⁃Wear Characteristics at Different Lubricating Oil Temperatures
    Liang Yu,Biao Ma,Changsong Zheng,Yujian Liu,Fuhua Wei,Renqi Yang
    2021, 43 (10):  1536-1542.  doi: 10.19562/j.chinasae.qcgc.2021.10.016
    Abstract ( 136 )   HTML ( 1 )   PDF (2994KB) ( 187 )   Save

    The changes of groove area of friction disc and the lubricating oil temperature can affect the contact status of friction pair, which has a significant impact on the friction?wear properties of the clutch. A micro-contact numerical model of asperity summits is proposed to investigate the influence of lubricating oil temperature on the local contact pressure and contact area of the friction pair. Meanwhile, the clutch bench test is conducted to reveal the influence of the groove area of the friction disc on the clutch friction?wear properties under different lubricating oil temperatures. The results show that the increase of lubricating oil temperature leads to the rise of the local contact area and the maximum contact pressure. With the increase of the lubricating oil temperature, the differences of the friction torque and friction coefficient are more and more significant under different groove area conditions. With the increase of the groove area, the wear of friction disc becomes more serious and the carbon black absorbed is reduced.

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    Research on Anomaly Detection of In⁃Vehicle CAN Bus Based on Entropy
    Haichun Zhang,Rongshuai Jiang,Jie Wang,Zhaojun Lu,Zhenglin Liu
    2021, 43 (10):  1543-1548.  doi: 10.19562/j.chinasae.qcgc.2021.10.017
    Abstract ( 175 )   HTML ( 9 )   PDF (1907KB) ( 205 )   Save

    Due to lack of encryption, integrity verification, and identity authentication mechanism, the vehicle Controller Area Network (CAN) bus is prone to attacks that cause abnormal bus data frame flow. In order to detect the abnormal data frame traffic injected by the attacker into the vehicle CAN bus, this paper analyzes the vehicle CAN bus anomaly detection mechanism based on information entropy, and proposes a vehicle CAN bus anomaly detection mechanism based on relative entropy, which makes up for the former's defect of inability to detect abnormal details of the defect. The experimental results on a certain Ford vehicle show that the CAN bus anomaly detection mechanism based on relative entropy can not only detect the abnormal flow of bus data frames caused by DoS attacks and replay attacks, but also detect specific attack types and abnormal CAN ID of the frame, with high detection efficiency.

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    Study on Vehicle Sound Synthesis Algorithm Based on Cylinder Pressure Signal
    Liping Xie,Chihua Lu,Zhien Liu,Yawei Zhu,Kai Liu,Wei Sun,Lü Zhipin
    2021, 43 (10):  1549-1554.  doi: 10.19562/j.chinasae.qcgc.2021.10.018
    Abstract ( 148 )   HTML ( 4 )   PDF (1965KB) ( 192 )   Save

    In order to simulate the vehicle sound with good sound quality, a novel sound synthesis algorithm based on engine cylinder pressure signal (SS?BCPS) is proposed in this paper. Firstly, a sound particle index matrix is constructed according to the periodic characteristics of the engine cylinder pressure curve, and by setting the time?step of index rotational speed and matching the corresponding rotational speed interval range of index matrix, the duration of the sound signal in the interval range is calculated. Then based on the algorithm of variable speed with constant pitch, the sound particle segments in the interval range are deleted according to the raising multiplier, and the remaining sound particles are sequentially spliced to achieve the simulation of vehicle sound. Finally, MATLAB software is used to compile the visualized GUI program for SS?BCPS algorithm with a subjective evaluation conducted. The results show that the SS?BCPS algorithm proposed can not only simulate the vehicle sound matching the driver’s behavior, but also the sound is coherent and natural, usable for the development of real?time engineering.

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    The Fatigue Test of Rear Sub⁃frame Based on Stress Tensor Analysis
    Wenzheng Cheng,Xiaoqiao Yu,Xia Xiao,Yuanming Dong,Jie Hou
    2021, 43 (10):  1555-1564.  doi: 10.19562/j.chinasae.qcgc.2021.10.019
    Abstract ( 172 )   HTML ( 11 )   PDF (3213KB) ( 269 )   Save

    In view of that the component level fatigue bench test of rear sub-frame for five links rear suspension can't be conducted due to the interference between hydraulic actuators and hard to arrange, a fatigue test method based on stress tensor analysis is proposed. According to the stress state of potential dangerous points, the key load channels are identified, and the simple and implementable block spectra loads are defined respectively for two potential dangerous points. In the test scheme devised, the principal stress directions of dangerous points remain basically unchanged, their damage is close to that with original road spectra, and the conclusion of the test is consistent with that of suspension system test, with the cost of test and development risk reduced.

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