Table of Content

25 June 2024, Volume 35 Issue 06

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Research on Road Uneven Obstacle Recognition Method for Intelligent Vehicles

ZOU Junyi, LIU Chang, GUO Wenbin, YAN Yunbing, RAN Maoping

2024, 35(06):  951-961.  DOI: 10.3969/j.issn.1004-132X.2024.06.001

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For intelligent vehicles, if the sensing device might accurately and quickly detect the concave and convex obstacles on the roads ahead of the vehicles, the important preview information might be provided for the control of the chassis system such as the suspension of the vehicles, and finally realized the improvement of the comprehensive performance of the vehicles. Therefore, based on improved YOLOv7-tiny algorithm a recognition method was proposed for typical positive and negative obstacles such as bumps(speed bumps) and pits on the road surfaces. Firstly, the SimAM module was introduced in the three feature extraction layers of the original YOLOv7-tiny algorithm to enhance the networks ability to perceive the feature map; secondly, a smoother Mish activation function was used in the Neck part to add more nonlinear expressions; again, replacing the nearest proximal upsamping operator with the up-sampling operator to enable the network to aggregate contextual information more efficiently; and lastly, the WIoU was used as the localization loss function to improve the convergence speed as well as the robustness of the network. The offline simulation experimental results show that compared with the original model, the improved model improves the average accuracy by 2.5% for almost the same number of parameters with an intersection ratio of 0.5 between the predicted and real frames. The improved model is deployed to a real vehicle, and the real-vehicle experiments verify that the model may effectively detect the obstacles appearing on the road in front of the vehicles, indicating that the proposed algorithmic model may accurately provide the pre-precedent information for obstacle detections.

A Lateral Slope Curve Tracking Control for Autonomous Vehicles Considering Dynamic Adaptive Sideslip Angles

ZHANG Wei1, GAO Aiyun1, FU Zhumu2, ZHAO Enhui1, CHEN Qianan1

2024, 35(06):  962-972.  DOI: 10.3969/j.issn.1004-132X.2024.06.002

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To address the problems that the autonomous vehicle deviated from the expected trajectory at the lateral slope curve, and even losed stability owing to severe sideslipping, a dynamic adaptive control strategy for sideslip angle was proposed. To overcome the change of tire cornering stiffness caused by the changes of vertical loads of the vehicles, the load matching diagram was obtained by fitting multiple sets of data. Then, a lateral trajectory tracking controller was designed based on the model prediction control algorithm. In line with the entry speed of the vehicles into the turn, the prediction horizon was selected. Meanwhile, the transient-state and steady-state sideslip angle were selected in line with the road curve. Through online optimization, the optimal front wheel steering angle was generated. Finally, the CarSim/Simulink joint online simulation system and the real vehicles system were established for verification. The results demonstrate that the proposed control strategy may ensure that the vehicles will not have serious sideslip under the lateral slope inclination angle of around 7% and the curved road. In addition, the proposed control strategy improves the tracking accuracy of the autonomous vehicles in the lateral slope curve tracking task and makes the vehicles have good lateral stability.

Vehicle Motion State Estimation Based on WOA-SVR

YOU Yong1, 2, MENG Yunlong1, 2, WU Jingtao1, 2, WANG Changqing3

2024, 35(06):  973-981，992.  DOI: 10.3969/j.issn.1004-132X.2024.06.003

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In order to accurately obtain vehicle motion state information without relying on the accuracy of the dynamics model, a vehicle state estimation algorithm was proposed based on WOA-SVR. Firstly, by analyzing the basic characteristics of vehicle dynamics, a SVR architecture was designed for estimating the separation of lateral velocity, yaw rate, and vehicle speed. Then, the SVR model was trained on a dataset composed of multiple driving conditions, and the WOA was used to optimize the penalty factor c and kernel function parameter g in the relaxation variables during the training processes. Finally, the estimation algorithm was validated through virtual simulation of single line shift and frequency sweep tests, as well as ABS braking and double line shift actual vehicle tests. The results show that this algorithm effectively improves estimation accuracy and is robust to changes in speed, enabling accurate estimation of vehicle motion states without relying on dynamics models.

RBF Neural Network Adaptive Control for Autonomous Electric Vehicles Based on Parameter Prediction

CHEN Zhiyong, LI Pan, YE Mingxu, LIN Xinyou

2024, 35(06):  982-992.  DOI: 10.3969/j.issn.1004-132X.2024.06.004

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Based on parameter prediction， a RBF neural network adaptive control scheme was proposed for the motion control problems of autonomous electric vehicles with uncertainties. Firstly, the influences of system parameter uncertainties and external interferences were considered, and a dynamic model which might reflect the tracking and following behaviors of vehicles was established by the preview method. Secondly, RBF neural network compensator was adopted to compensate system uncertainties adaptively, and a generalized coordinated control law was designed for the lateral and longitudinal motions of vehicles. Thirdly, the impacts from the front vehicle speeds and road curvatures were taken into account, and the minimization of the energy consumption and the average jerks in the tracking and following control processes were regarded as the optimization objects. Afterwards, PSO algorithm was utilized to rolling optimize the gain parameter K in the coordinated control law, and then a series of optimized sample data were obtained. Then, to ensure the economy and ride comfort of vehicles, a BP neural network was designed and trained to realize the real-time prediction of gain parameter K in the generalized coordinated control law. Simulation results validate the effectiveness of the proposed control scheme.

Cooperative Optimization of Intelligent Vehicle Path Planning Based on PSO-SSA and RRT

ZHANG Zhiwen1, 2, LIU Bowei3, ZHANG Jiyuan1, TANG Jie1, ZHANG Tianci1, 2

2024, 35(06):  993-999，1009.  DOI: 10.3969/j.issn.1004-132X.2024.06.005

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Regarding the issues of long response time and low planning efficiency in the path planning algorithms for smart vehicles facing diverse working scenarios, a multi-element collaborative optimization strategy was proposed. Firstly, the vigilance mechanism of SSA was integrated with the population optimization characteristics of PSO, optimizing the inertia weight factor and learning factor in the PSO algorithm. Secondly, a “triangular wiring” search rule was introduced to perform bidirectional optimization(RRT-Connect) on the RRT algorithm. Subsequently, a complex environmental road simulation model was established using MATLAB software, and simulation tests were conducted on the proposed optimization solutions. The results demonstrate that, compared to single optimization approaches, the collaborative optimization algorithm exhibits significant advantages in terms of path length and planning time. Finally, real-vehicle tests are conducted on the application scenarios of the two collaborative optimization solutions, showing that in local path planning, the SSA-PSO algorithm has a shorter response time and higher planning efficiency, while in global path planning, the “triangular wiring” RRT-Connect algorithm exhibits greater advantages.

Research on Path Tracking Control Based on Optimized Dynamics Model

HE Zhicheng1, WANG Yufan1, WEI Baolv1, 2, LI Zhi1, BU Tengchen1

2024, 35(06):  1000-1009.  DOI: 10.3969/j.issn.1004-132X.2024.06.006

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In response to the poor adaptability of conventional path tracking model predictive controllers under high-speed and large-curvature conditions, an adaptive prediction horizon control strategy was proposed based on optimized dynamic models. Firstly, to address the issues of insufficient accuracy of classical dynamics models under high lateral acceleration conditions, an optimized model including roll steer and compliance steer was established, achieving higher precision prediction of vehicle states. Secondly, to address the issues of fixed prediction horizon control under high-speed and large-curvature conditions, an adaptive prediction horizon strategy was proposed based on two-dimensional Gaussian function, achieving real-time adjustment of preview distances with low algorithm complexity. Finally, the effectiveness of the controller on double-lane-change roads was verified throught CarSim/Simulink joint simulation. Results show that a reduction of 45.1% in lateral position peak errors and 72.4% in yaw angle peak errors indicate better adaptability of the designed controller to extreme conditions.

Impact Analysis of Helical Gear Mesh Bending Moment on Planetary Gear Journal Bearings Transient Lubrication Performance in Wind Turbine Gearboxes

LI Hao1, TAN Jianjun1, ZHU Caichao1, SUN Yizhong2, SUN Zhangdong3, WANG Hongxia3

2024, 35(06):  1010-1022.  DOI: 10.3969/j.issn.1004-132X.2024.06.007

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The journal bearings of planetary gears in wind turbine gearboxes were often designed with the inner holes of the planetary gears and the pin shaft as the shaft sleeve and journal, respectively. However, the meshing bending moment of the helical gears might easily cause misalignment between the planetary gears and the pin shaft, resulting in high risk of edge contact and affecting the operating life. Taking the planetary gear journal bearing of a 6 MW drive chain gearbox as the research object, considering the dynamic effects of radial load, bending moment, and speed of the journal bearing, a transient tribo-dynamic coupling model of the planetary gear journal bearing was established. The dynamic meshing force and time-varying speed of the planetary gear extracted from the SIMPACK dynamic model of the wind turbine drive chains were used as the load and motion boundary inputs for the planetary gear journal bearings. The influences of the helical gear meshing bending moment, input torque, and journal bearing radius clearance on the lubrication performances of the planetary gear journal bearing were analyzed, and experimental verification was conducted. The results indicate that the dynamic meshing force and generated meshing moment  of the planetary gear will cause dynamic cyclic changes in the axial positions and deflection angle of the planetary gear, and as the load increases, the oil film/solid contact pressure and misalignment moment of the planetary gear journal bearings will gradually increase. Reducing the radial clearances of planetary gear journal bearings may effectively improve their transient lubrication performance.

Identification of Rotary Axes PIGEs of Five-axis CNC Machines with Double Rotary Tables

ZHANG Wenbin, LIU Huanlao, WANG Yulin, ZHOU Hengyu

2024, 35(06):  1023-1033.  DOI: 10.3969/j.issn.1004-132X.2024.06.008

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Aiming at the problems of the accuracy in identifying geometric errors of rotation axis of five-axis CNC machines with double rotary tables, an identification model of PIGEs of rotation axis on absolute coordinate system was proposed. The actual initial coordinates of the tool ball and the workpiece ball in the machine coordinate system were established, and the actual initial position of the workpiece ball in the measured axis was obtained by the inverse matrix. The mathematical model of the double ball bar length changing included installation errors and the PIGEs of the rotation axis was established based on the four measurement patterns. The effects of PIGEs on the measurement pattern were analyzed by simulation. The results show that the parallelism error may not affect double ball bar length changing when the tool ball is at the intersection of the two rotation axis. Finally, 8 PIGEs of the rotary axis were identified through experiments, and 4 positional deviations of the rotary axis PIGEs were compensated. The experimental results show that the maximum absolute value of the compensated positional error is reduced from 203.5 μm to 5.1 μm, and the proposed identification model may effectively improve the accuracy of five-axis CNC machines. 

Adaptive Variable Impedance Control for Force Sensor-less Joysticks

NI Tao1, 2, ZHANG Panhong1, 2 , ZHAO Zeren1, 2

2024, 35(06):  1034-1043，1051.  DOI: 10.3969/j.issn.1004-132X.2024.06.009

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A lightweight and compact two-degree-of-freedom joystick was designed herein, and an adaptive variable impedance control strategy of sensor-less was proposed based on the joysticks. Firstly, the impedance parameters were adjusted according to the control forces of the operators to adapt to the different control habits of the operators. Secondly, in addition to ensuring accurate position control, the velocity control at the end-effector of the joystick was also added to improve the operator's control experience. Then, based on the variable impedance compliance control, the teleoperation force estimation control strategies were added to avoid the increase in system complexity caused by the extra wiring of the force sensor and the corresponding measurement noises. The stability of the above control strategies was proved in the Lyapunov sense, which shows that the control errors are convergent and the responses of the whole closed-loop system are uniform ultimate boundedness(UUB). Finally, the validity and stability of the above strategies were verified by simulation experiments and actual bench experiments.

Digital Flexible Detection Method for Rotor Blade Twist Angles

TANG Yuyang, CHEN Long, XIAO Qingdong

2024, 35(06):  1044-1051.  DOI: 10.3969/j.issn.1004-132X.2024.06.010

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The twist angles of helicopter rotor blades had a direct impact on the performance and service life of the blades. However, the traditional methods of detecting twist angles relied heavily on specialized fixtures and measuring tools, which were inflexible, inefficient and inaccurate. To address this issue, a digital flexible detection method for rotor blade twist angles was proposed, and a detection system for rotor blade twist angles was designed and constructed. This system enabled automatic detection of rotor blade twist angles and might greatly improve detection efficiency and accuracy to meet the detection requirements of different types of rotor blades. A twist angle calculation method was proposed based on key section local contour registration. The point clouds on the surfaces of rotor blades were collected by laser scanning sensor, a point cloud registration method was employed by combining coarse registration based on principal component analysis(PCA) algorithm and fine registration based on improved iterative closest point using K-dimension tree(KD-ICP) algorithm to accurately and efficiently calculate the twist angle values, which provided a general and effective calculation method for rotor blade twist angle calculation. Finally, experiments were conducted on a certain type of rotor blade as the detection object. The results show that the maximum error of twist angle detection is as 54″, and the repeatability accuracy is as 18″, which proves the effectiveness and accuracy of the systems.

Research on CNC Milling Machine Cutting Power Prediction Model Considering Tool Wear Based on VMD-SSA-LSTM

WANG Qiulian1, OU Guixiong1, XU Xuejiao1, LIU Jinrong1, MA Guohong2, DENG Hongbiao2

2024, 35(06):  1052-1063.  DOI: 10.3969/j.issn.1004-132X.2024.06.011

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Traditional researches of cutting process powers required complex cutting power models and often neglected the influences of tool wear, so a CNC milling machine cutting power prediction model considering tool wear was designed based on VMD, SSA, and LSTM neural network. This model did not require the deconstruction of the energy consumption mechanism during the operation of CNC milling machines, and achieved high-precision prediction of cutting process powers based on historical experimental data. Firstly, artificial intelligence machine vision technology was used to analyze and process images of the tool wear, obtaining digital features of the worn tools and determining the maximum wear. Then, the VMD-SSA-LSTM model was established, which considered tool wear in the prediction of CNC milling machine cutting powers. VMD was used to decompose the operational data of CNC milling machines, and then the SSA algorithm optimized the hyperparameters of the LSTM neural network. The decomposed milling machine data components were input into the LSTM neural network, and the predicted values of each component were summed to obtain the cutting power prediction value. Taking face milling as an example, the proposed prediction model was compared and analyzed against BP neural networks, LSTM neural networks, and traditional models, which validated the effectiveness and superiority of the proposed model.

Robot Vision Closed-loop Pose Autonomous Coordination Method with Second-order Cone Constrained Programming

ZHONG Xungao1, 4, LUO Jiaguo1, TIAN Jun2, ZHONG Xunyu2, PENG Xiafu2, LIU Qiang3

2024, 35(06):  1064-1073.  DOI: 10.3969/j.issn.1004-132X.2024.06.012

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A robot “hand-eye” pose autonomous coordination was regarded as a uncalibration constrained programming  problem, and a visual closed-loop control method was proposed based on second-order cone constrained programming. Firstly, the visual servoing control algorithms were constructed in the image planes and Cartesian space, respectively based on images and positions. After that, by established the path constraint and the local minimal constraint rules, and a second-order cone convex optimization model was constructed to realize the compromise optimal control of image feature trajectory and robot motion path. Moreover, the proposed second-order cone constrained programming model was embedded with an adaptive state estimator, to realize robotic Jacobian matrix online mapping learning, and to solve the unknown problems of “hand-eye” calibration parameters and visual depth information. Finally, the uncalibrated robot visual positioning experiments prove the effectiveness of the convex optimization planning model, and the real grasping tasks illustrate the feasibility of the robot pose autonomous coordination.

Robust Registration Method for Vehicle Body Components under Abnormal Point Cloud Interference

DING Tao1, 2, WU Hao1, 2, ZHU Dahu1, 2

2024, 35(06):  1074-1085.  DOI: 10.3969/j.issn.1004-132X.2024.06.013

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Point cloud registration was a key method for pose parameter measurement of large vehicle body components, but the existing algorithms were difficult to register to effective pose under a large number of abnormal point cloud interference, thereby resulting in matching distortion and inability to ensure the quality of subsequent robotic operations. To address the issue, a robust registration algorithm for vehicle body components, robust function weighted variance minimization(RFWVM) algorithm was proposed that might effectively suppress the interference of abnormal point cloud. A robust function weighted objective function was established, and the influences of abnormal point cloud in the registration processes were suppressed by applying dynamic weights that varied with the number of iterations. The rigid transformation matrix was solved iteratively by the Gauss-Newton method. The experimental results on the side walls of high-speed rail body and car door frames demonstrate that the proposed RFWVM algorithm has higher registration accuracy compared to classic algorithms, such as interactive closure point(ICP), variance minimization(VMM), weighted plus and minimum allowance variance minimization(WPMAVM), de-pseudo-weighted variance minimization(DPWVM), may effectively suppress the influences of various abnormal point clouds on registration results, and also behaves better stability and robustness. The method may effectively achieve the accurate registration of various vehicle body components.

Optimization Decision Method for Cartridge Case Indenting-heading Process Parameters Driven by Small Sample Data

2024, 35(06):  1086-1096.  DOI: 10.3969/j.issn.1004-132X.2024.06.014

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Aiming at the problems of low quality and short die life during the production commissioning, an optimization decision method for cartridge case indenting-heading process parameters driven by small sample was proposed. Firstly, the central composite experimental method was used to design experiments, and each experimental scheme was incorporated into the finite element model for numerical simulation. Taking the maximum effective stress of indenting ejector, the maximum effective stress of heading punch and inner fillet at the bottom of the cartridge case as the optimization goals, random forest algorithm was combined to construct the multi-objective optimization model of processing parameters in indenting-heading processes of cartridge cases based on the simulation results. Secondly, the improved multi-objective grey wolf algorithm was applied to optimize the multi-objective optimization model and obtain a pareto solution. The optimal process parameter combination was evaluated and determined using the comprehensive entropy weight-TOPSIS method. Finally, the numerical simulation and processing experiments were carried out with the combination of optimal process parameters. The results show that the simulation results are consistent with the processing experiments, and the inner fillets at the bottom of the cartridge cases are filled fully, and the service life of the die is improved.

Study on Influence Rules of Residual Stress on Thermal Fatigue Life of GH3230 Laminate Welds

DONG Zhibo1, LI Chengkun1, WANG Chengcheng1, HAN Fang1, ZHANG Zhihang1, TENG Junfei2, LYU Yanlong2

2024, 35(06):  1097-1102.  DOI: 10.3969/j.issn.1004-132X.2024.06.015

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In order to investigate the influences of residual stress on the service life of weld seams of laminate cooling structures, first of all, finite element simulation and experimental verification were carried out on the laser welding processes of GH3230 laminate under conventional conditions. Then corresponding regulated approaches including pre-stretching and thermotensile et al. were simulated and analyzed. Afterwards, the evolutions of temperature and equivalent stress during service periods with and without residual stress were studied respectively. The service life was later evaluated using Coffin-Manson model modified by Morrow. The results demonstrate the thermal fatigue life caused by residual stress is significantly decreased. Furthermore, the stress amplitude and the mean stress while servicing, which decreasing 70% and 25% respectively, are effectively improved using regulating approaches mentioned above. Regulating welding residual stress is of vital importance for improving the thermal fatigue life of laminate structures.

Research on Difference of Fracture Splitting Performance and Quality Defect Analysis for 36MnVS4 and 46MnVS5 Connecting Rods

KONG Yankun1, DENG Wei1, JIN Guozhong2, LEI Jilin1, CHEN Liqiong3, JIA Dewen1

2024, 35(06):  1103-1111，1119.  DOI: 10.3969/j.issn.1004-132X.2024.06.016

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 A comparative analysis was conducted on the fracture splitting processing performance of two types of high-strength connecting rods, 36MnVS4 and 46MnVS5, which were made from non-quenched and tempered materials. The reasons that affected the quality of connecting rod cracking were explored, and the boundaries for connecting rods cracking processing were optimized. The impacts of the connecting rod structures on the fracture-splitting processing performance were analyzed as well. The distribution characteristics of principal stresses and plastic strains at the roots of the cracking grooves were analyzed, and the crack initiation positions for connecting rods made of different materials were determined. The crack propagation processes of the connecting rods were simulated using the finite element software ABAQUS and FRANC3D, and a comparative analysis was conducted. The loading speed for the cracking processing of the 36MnVS4 materials was optimized. The impacts of the connecting rod structures on the cracking performance were analyzed.The results indicate that under the same boundary conditions, the cracking performance of 46MnVS5 material is better, with the tendency to have a unique crack initiation position, low notch sensitivity, good fracture brittleness, faster crack propagation speed, and higher required crack load. At a loading speed of 25 mm/s, the cracking performance of 36MnVS4 material improves. Connecting rod structures with smaller theoretical fracture surface area exhibit relatively better cracking performance.

Research on Design and Applications of Grinding Profiles of P75 Rail on Sharp Curve

LIU Yongqian1, 2, REN Zunsong1, HOU Yinqing2, WU Xiao2, WANG Junping2

2024, 35(06):  1112-1119.  DOI: 10.3969/j.issn.1004-132X.2024.06.017

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Taking the P75 rail on R400 m curve of a heavy-haul railway as the research object, the description model of wheel-rail contacts and wheel diameter difference curve was established, and the representative measured wheel treads and rail profiles were selected. The rail profiles in the wheel-rail contact areas were optimized by the reverse solution method of the wheel diameter difference curves, and the grinding profile of the curves was designed according to the principle of minimizing the amounts of grinding. A simulation model of vehicle-track multi-body dynamics with real parameters was established in the multi-body dynamics software, and the dynamic indexes matching with measured and designed profiles were compared and analyzed. The R400 m curve was ground with designed profiles, and the wheel-rail dynamics tests were carried out. The results show that, after optimization, the curves of wheel diameter difference tend to be smoother, the curve passing ability of vehicle is improveds, and the anti-derailment ability is maintained. The wheel-rail relationship is significantly improved matching with the designed profiles, and the cross-jumping and concentration problems at the wheel-rail contact points are alleviated. The lateral wheel-rail force was reduced by more than 20%, the derailment coefficient was reduced by more than 16%, the normal contact stress of the rail is reduced by more than 32%, and the wheel-rail creep force was reduced by more than 26%. After grinding with the designed profile, the lateral wheel-rail force is reduced by more than 34%, the derailment coefficient is reduced by more than 34%, the vibration acceleration of the rail is reduced by more than 35%, the fatigue damage of the rail surface doesnt develop significantly in 3 months, and the service life of the rail is extended from 8 months to 13 months. The application effectiveness of rail profile design method on sharp curve in heavy-haul railway is verified through simulation analysis and field tests.

Adaptability Analysis of Composite Radial Mechanisms in Metro Vehicles

ZHENG Yang, DAI Liangcheng, CHI Maoru, GUO Zhaotuan, ZENG Pengcheng

2024, 35(06):  1120-1128.  DOI: 10.3969/j.issn.1004-132X.2024.06.018

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Setting up radial mechanisms was the main measure to solve the contradiction between serpentine stability and curve passing performance of railway vehicles. However, the conventional lever-type forced-guided steering rack operated in a low-equivalent taper state, where the presence of the linkage exacerbated the vehicles primary-hunting, which in turn led to a decrease in vehicle stability. Aiming at the above-mentioned defects of the traditional lever-type forced-guided bogie, a composite radial mechanism was proposed. This radial mechanism enabled the vehicle to operate in small radius curves with the function of forced guidance, and the vehicle operated in large radius curves or straight lines so that the function of forced guidance was invalidated, thus the shortcomings of the traditional forced-guided bogies were overcome. Based on the working principle of the composite radial mechanisms, the numerical simulation model and control module of the mechanisms were established. Then MATLAB/Simulink was used to jointly simulate the numerical models of the composite radial mechanisms and the dynamics models of the subway vehicles to study the effects on the dynamics performance of the vehicle systems. Then the results were verified by bench testing. The results show that the composite hydraulic radial mechanisms ensure the vehicle has good curve passing performance, and greatly improves the stability of the vehicles.

Fatigue Analysis and Experimental Study of Aluminum Alloy No-rivet Clinch Connections Based on Equivalent Structural Stress Method

ZENG Weihe, GOU Ligang, WANG Mingqing, WANG Lei, YU Ronggui

2024, 35(06):  1129-1139.  DOI: 10.3969/j.issn.1004-132X.2024.06.019

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The aluminum alloy no-rivet clinch connection was used as research object. By testing tensile strength and fatigue mechanical properties of three group lapped specimens with unequal thickness, the fatigue fracture behavior of aluminum alloy no-rivet clinch connection were studied and the load force-life(F-N) distribution of specimens was obtained. According to specimen fatigue test conditions, the equivalent FEA model was established to calculate equivalent structural stress amplitudes(ΔSs), Weibull analysis was carried out on the measured fatigue life scatter data and key parameters of master ΔSs-N(S-N) curve for no-rivet clinch connections were obtained by fitting with the least square method. The fitted master S-N fatigue life curve was applied to predict fatigue damage of no-rivet clinch connections when the all-aluminum hood of pure electric vehicle experiencing dynamic closing load case. Research results suggeste that: the fatigue cracking of no-rivet clinch connections occur at necking position and ΔSs-N curve satisfy power function relation. By optimizing the point number and positon of no-rivet clinch connections, the maximum damage of no-rivet clinch connections in the key area of all-aluminum alloy hoods was reduced from 1.08 to 0.78, which satisfice hood dynamic closing durability performance design requirements of pure electric vehicles. The developed calculation method and master S-N curve parameters may provide a theoretical basis for the fatigue simulation and optimization of no-rivet clinch connections on vehicle bodies.