Archive

27 March 2024, Volume 49 Issue 6 Previous Issue   
---
New Energy Vehicle
Intelligent Connected Vehicle
Design and Research
Testing and Experiment
Process·Materials
Automobile Education


For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

New Energy Vehicle

Select

Research on Compensation Strategy for EPS System of High Torque Commercial Vehicle CAI Xuechang 2024, 49(6): 1-7.  DOI: 10.16638/j.cnki.1671-7988.2024.006.001 Abstract ( )   PDF (1492KB) ( )   Vehicle return to center control is an important factor that determines the quality of the steering system. Aiming at the problems of under-alignment or overshoot in new-energy high-torque commercial vehicles, a fuzzy proportional-integral-differential (PID) control algorithm based on multi-population genetic algorithm (MPGA), optimization is proposed. The electric power steering (EPS) system dynamic model, steering wheel angle estimation model and back-to-center compensation control strategy are established. Then determine the armature voltage of the motor according to the expected output torque, so as to realize the return compensation. The parameters of fuzzy PID controller are optimized by using MPGA. The Simulink simulation test proves that the proposed fuzzy PID control algorithm based on MPGA optimization, compared with the PID control algorithm and fuzzy PID control algorithm, has improved return performance. References | Related Articles | Metrics

Select

Research on the Competitiveness Measurement of China's Self-owned Brand New Energy Automobile Enterprises－From the Perspective of Sustainable Balanced Scorecard TAN Dexiang 2024, 49(6): 8-14.  DOI: 10.16638/j.cnki.1671-7988.2024.006.002 Abstract ( )   PDF (849KB) ( )   In order to accurately grasp the basic pattern of China's own brand new energy automobile enterprises, cultivate the competitive position of enterprises, and promote the sustainable development of enterprises. Based on the sustainable theory and corporate social responsibility, this paper improves the balanced scorecard, establishes the competitiveness evaluation index system of China's self-owned brand new energy enterprises from the three dimensions of finance, management and society, and analyzes the development status of China's self-owned brand new energy automobile enterprises. It is found that there are some problems in domestic new energy automobile enterprises, such as large gap in comprehensive competitiveness, insufficient survival ability of enterprise main body, and unreasonable structure of enterprise resources. Finally, it puts forward countermeasures and suggestions such as reforming the top-level design of new energy automobile enterprises and improving the independent ability of new energy automobile brands. References | Related Articles | Metrics

Select

Failure Analysis of Electric Vehicle Pre-charging Relay DONG Yujun 2024, 49(6): 15-20.  DOI: 10.16638/j.cnki.1671-7988.2024.006.003 Abstract ( )   PDF (5244KB) ( )   The pre-charging system of new energy electric vehicles is crucial to vehicle safety. In order to furtherly improve the reliability of the pre-charging system and to propose practical and reliable control measures, this paper analyzes in depth the reasons for the functional failure of the pre-charging system. Through the systematic troubleshooting method, it is found that the abnormally high surface resistance of the contacts of the pre-charging relay is the direct cause of the pre-charging failure. Suction test, computed tomography (CT), microscope inspection, and scanning electron microscope analysis are conducted. The results show that some parts in the battery management system (BMS) have free monomeric phosphorus and volatile silicone, and material migration occurs during high-voltage operation, and the elements of silicon and phosphorus migrate to the surface of the relay contacts, resulting in an abnormally high contact resistance, which ultimately triggers the pre-charging functional failure. The application of this paper concludes that the red phosphorus and siloxane content of BMS system parts needs to be controlled during the design and mass production stage to ensure the reliability of the pre-charging system. The research has strong practical application and reference value. References | Related Articles | Metrics

Select

Study of Electric Vehicle Air Conditioner Recirculation Flap Fuzzy Control YU Shuliang 2024, 49(6): 21-27.  DOI: 10.16638/j.cnki.1671-7988.2024.006.004 Abstract ( )   PDF (1631KB) ( )   Electric vehicle air conditioner recirculation control is important to cabin anti-fog, air fresh, energy consumption and so on, but it is difficult to establish exact mathematical model for the control of the recirculation flap. In this paper, the fuzzy control method is used, and fog risk, CO2 concentration, and air conditioner load are used as input, and recirculation flap opening is used as output. Using Gaussian function, the fuzzy controller is established by MATLAB Simulink, and vehicle air conditioner model is established by Simscape. Through simulation verification, the fuzzy control method of internal and external circulation damper can have good control effect on the anti-fog of passenger cabin, air freshness, air conditioning energy consumption and other aspects. Compared with the fixed proportion external circulation control, the fuzzy control has the highest comprehensive score and the best comprehensive performance. References | Related Articles | Metrics

Select

Research on a New Connection Support Structure for Battery Electric Vehicle Chassis Sxhibition Equipment ZENG Zhaoguo 2024, 49(6): 28-33.  DOI: 10.16638/j.cnki.1671-7988.2024.006.005 Abstract ( )   PDF (2317KB) ( )   This paper aims to introduce an innovative connection support structure for battery electric vehicle chassis exhibition equipment, in order to solve the problems faced by traditional manufacturing methods and improve the display effect and cost-effectiveness of chassis exhibition equipment. The method of connecting the complete lower body assembly of a commercial vehicle has the problems of long production cycle, high cost, and poor display effect. In order to overcome these problems, this paper propose a new design scheme based on steel pipe connection support structure. By selecting appropriate strength steel pipe materials, designing steel pipe lengths and bending angles, the support connection between the front and rear axles of the chassis and the lower part is achieved to meet the production and display requirements of the chassis exhibition equipment. References | Related Articles | Metrics

Select

Life Cycle Environmental Benefit Assessment of Plug-in Hybrid Electric Vehicles ZHANG Chunmei 2024, 49(6): 34-37.  DOI: 10.16638/j.cnki.1671-7988.2024.006.006 Abstract ( )   PDF (791KB) ( )   Plug in hybrid electric vehicle (PHEV) is one of the popular models in the field of new energy vehicles. To evaluate the environmental benefits of plug-in hybrid dectric vehicles, this article adopts the theory of full life cycle assessment and selects Toyota Lexus plug-in hybrid electric vehicles as the research object. The material flow and energy flow inventory data are sorted out, and a life cycle assessment model is built based on GaBi software to evaluate their full life cycle material resource consumption and fossil energy consumption. The evaluation results indicate that plug-in hybrid electric vehicles have the highest proportion of material resource consumption in the raw material acquisition stage, with lithium batteries and main reducers consuming the largest amount of material resources. The main reason is that lithium batteries use more metal resources such as lithium and copper than other body components; Plug in hybrid electric vehicles have the highest proportion of fossil energy consumption during operation and use. After comparing nominal fuel with measured fuel, it can be concluded that the significant consumption of fuel and electricity during operation and use is the main reason for the highest proportion of fossil energy consumption during operation and use. References | Related Articles | Metrics

Select

Development Status and Trends of Humidifiers for Automotive Fuel Cell Engines ZHANG Shenglei 2024, 49(6): 38-42.  DOI: 10.16638/j.cnki.1671-7988.2024.006.007 Abstract ( )   PDF (1291KB) ( )   The humidifier, as the core component of the air supply system in the fuel cell balance of plant (BOP), delivers air with stable flow and humidity to the fuel cell engine. It plays a crucial role in maintaining humidity balance, protecting membrane electrode components, and improving fuel cell performance. It is crucial for the stable operation and performance improvement of the fuel cell system. This article reviews and analyzes the current development status of humidifiers, compares the performance and parameters of mainstream humidifiers in the current market, and looks forward to the technological development trend of humidifiers based on the industry development status. References | Related Articles | Metrics

Intelligent Connected Vehicle

Select

Research on Control Strategy Test Method of Automatic Parking System Based on Different Driving Habits ZHANG Shengqiang 2024, 49(6): 43-48.  DOI: 10.16638/j.cnki.1671-7988.2024.006.008 Abstract ( )   PDF (1368KB) ( )   The improvement of the accuracy and effectiveness of automatic parking system will promote the development of automatic parking technology. The paper designs the test scheme, selects the key test scenes and analyzes the driving habits of the automatic parking system, and analyzes the performance of the automatic parking system in different scenarios and working conditions. Through function analysis, scene test, signal acquisition and data analysis, a scheme is proposed for the development and design of automatic parking function. The test results show that no matter for parallel or vertical parking spaces, the automatic parking based on the passenger side is more effective than the automatic parking based on the main driver side, but it needs to be further improved in terms of time and efficiency, and the performance parameters need to be further optimized. References | Related Articles | Metrics

Select

Vehicle Obstacle Avoidance Path Planning and Tracking Based on Model Predictive Control LI Gefeng 2024, 49(6): 49-54.  DOI: 10.16638/j.cnki.1671-7988.2024.006.009 Abstract ( )   PDF (1291KB) ( )   Aiming at the problem of obstacle avoidance path planning for intelligent vehicle, an obstacle avoidance path planning and design method based on improved artificial potential field method is proposed. Firstly, the vehicle speed information is introduced into the traditional repulsive potential field function, the lane center line and road boundary potential field are designed, and the path obstacle avoidance planning controller is designed; Then, aiming at the problem of intelligent vehicle path tracking control, a three-degree-of-freedom vehicle dynamics model is established, and the horizontal and longitudinal tracking controllers are designed by using linear time-varying model predictive control and back propagation-proportional-integral-differential (BP-PID) control algorithm, respectively, to track the lateral position and longitudinal velocity of the vehicle; Finally, based on the CarSim/Simulink co-simulation platform, the validity of the design method is verified in the double line shifting condition and the straight line condition. The simulation results show that the safe and reliable obstacle avoidance path can be obtained by using the improved artificial potential field method, and the designed horizontal and longitudinal tracking controller has good tracking performance. References | Related Articles | Metrics

Select

Design of Emission Warning and Monitoring System for Heavy Duty Diesel Vehicles Based on Stream Processing SUN Tao 2024, 49(6): 55-60.  DOI: 10.16638/j.cnki.1671-7988.2024.006.010 Abstract ( )   PDF (945KB) ( )   In order to monitor the pollutant emission indicators of heavy-duty diesel vehicles in real time and quickly screen vehicles with excessive emissions, the Apache open-source big data framework with Flink as the core computing engine is used to achieve real-time processing of the data sent back by the heavy-duty vehicle emission on-board terminal and calculate the vehicle pollutant emission level. Based on the calculation results, the information of vehicles with excessive emissions will be pushed to vehicle users, after-sales departments, and research and development departments. At the same time, according to the requirements of the demand department, the operating conditions, configuration information, fault code information of the vehicles exceeding the standard are collected and analyzed to quickly locate the causes of excessive emissions. This will effectively improve social and economic benefits. References | Related Articles | Metrics

Select

Research on Lane Keeping Control Method of Sliding Mode Driver Based on Angle Compensation LI Xiao 2024, 49(6): 61-66.  DOI: 10.16638/j.cnki.1671-7988.2024.006.011 Abstract ( )   PDF (1239KB) ( )   Aiming at the situation that the intelligent vehicle cannot effectively track the target trajectory due to insufficient steering or excessive steering during the lane keeping process, this paper designs the vehicle lateral preview driver model based on the sliding mode variable structure control, and introduces the front wheel angle compensation control to establish the lane keeping model. The model can correct and optimize the corner in time to ensure that the vehicle maintains stability during the turning process. The simulation results show that the proposed lane keeping control method can realize the lane keeping function under the condition of high speed, and can correct and compensate the front wheel angle in real time under the condition of continuous curve. At high speed, the preview lateral deviation and heading deviation are reduced by 38.4 % and 37.6 % respectively, which has good path tracking performance. References | Related Articles | Metrics

Design and Research

Select

Modeling and Optimization of Headlamp Area Assembly Deviation Based on 3DCS LU Yuwei 2024, 49(6): 67-71.  DOI: 10.16638/j.cnki.1671-7988.2024.006.012 Abstract ( )   PDF (1465KB) ( )   The headlamp area of the car is an important part of the overall shape of the car, and the assembly quality of the headlamp assembly directly affects the overall performance and appearance quality. However, the design and adjustment of the headlamp area presents a number of challenges, especially in terms of matching with the surrounding parts, which directly affects the sensory quality of the vehicle. In order to solve this problem, the tolerance analysis software 3DCS is used to simulate the three-dimensional tolerance of the headlamp assembly in this paper. By comparing the results of the analysis, it is possible to identify the key elements of the assembly, which in turn optimizes the product structure and tolerances, and improves the assembly process. The practice shows that the assembly quality is significantly improved after the tolerance and positioning mode of parts with large out-of-tolerance rate are modified. Therefore, this method can be used to guide the preliminary design development work, improve the design stability, and have guiding significance in the early stage of assembly scheme design. References | Related Articles | Metrics

Select

Research on Performance of Interconnected Air Suspension Based on Mode Switching WANG Ying 2024, 49(6): 72-77.  DOI: 10.16638/j.cnki.1671-7988.2024.006.013 Abstract ( )   PDF (1463KB) ( )   To further improve the performance of interconnected air suspension, an interconnected mode switching strategy has been designed. This strategy first establishes an interconnected air suspension vehicle dynamics model. Then, based on the performance index functions of smoothness and handling stability, a comprehensive evaluation index is designed. By utilizing the changes in the comprehensive index under different connectivity modes, a control strategy for switching interconnection modes is designed. Finally, numerical simulation is conducted, and the simulation results show that the control strategy can significantly improve the performance of interconnected air suspension and enhance ride comfort. References | Related Articles | Metrics

Select

Optimization of Vehicle Tire Fastener Detection Method Based on Improved YOLO_v3 Algorithm ZHANG Baoyu 2024, 49(6): 78-83.  DOI: 10.16638/j.cnki.1671-7988.2024.006.014 Abstract ( )   PDF (1627KB) ( )   Tire disassembly is one of the necessary steps for repairing tires in the auto repair industry. Due to the excessive heavy truck tires, the lumbar spine is damaged by the lumbar spine. The EfficientNet-B4 lightweight network structure algorithm is now replaced with the main part of the YOLO_v3 algorithm (DarkNet-53) to realize the identification of tire fasteners in various models. The replaced network parameters are largely reduced, and the fastener sample training speed is accelerated. YOLO_v3 uses a duplex cross-entropy loss function to classify and calculate the loss of positive and negative samples. The Focal loss classification loss function is now replaced by the binary cross-entropy loss function, so as to propose a new neural network model (YOLO_v3-Nut). The experimental results show that the YOLO_v3-Nut model is better than the YOLO_v3 model in terms of training and recognition speed characteristics, and the model structure of this article is reduced by 43.01% compared with the YOLO_v3 model storage space. The speed is 36 fps, which is enough to complete the identification of tire fasteners in various models. References | Related Articles | Metrics

Select

Diagnosis and Optimization of Air Conditioning "Buzzing" of a Vehicle DENG Xin 2024, 49(6): 84-87.  DOI: 10.16638/j.cnki.1671-7988.2024.006.015 Abstract ( )   PDF (2099KB) ( )   With the continuous improvement of powertrain noise, vibration, harshness (NVH), road noise and wind noise of the vehicle, the NVH problem of the air conditioning system has become more and more prominent, and has been concerned and studied by the industry. This paper mainly diagnoses and analyzes the obvious "buzzing" sound in a vehicle under the creep condition of air conditioning, clarifies the generation and transmission mechanism of the "buzzing" sound of the air conditioning system, and puts forward optimization schemes such as engineering pipeline vibration isolation pad and pipeline extension according to the analysis results, which can effectively reduce the "buzzing" sound of air conditioning. References | Related Articles | Metrics

Select

Design of Lane Keeping Assist System LI Yihong 2024, 49(6): 88-93.  DOI: 10.16638/j.cnki.1671-7988.2024.006.016 Abstract ( )   PDF (1859KB) ( )   The lane keeping assist system (LKAS) has important safety functions and research significance, which can issue early warning and correct the deviation when the vehicle unintentionally deviates. A lane keeping assistance system is designed, which mainly includes lane departure warning module and lane centering control module. The data is collected by camera and image processing is done to determine whether the vehicle deviates from the lane according to the left and right lane lines and vehicle position status. If the vehicle deviates and the driver doesn’t actively control the vehicle, the departure warning sends out an audible and visual alarm and the control module adjusts the speed and direction of the vehicle. The vehicle approaches the center of the lane and drives along the center of the lane. The experimental vehicle is used to verify the lane keeping assist system. The results show that the system can realize lane departure warning and lane centering control, and has high stability and reliability. References | Related Articles | Metrics

Select

Simulation Analysis and Optimization of Sealing Surface of a Hybrid Electric Transmission Case GUO Shilu 2024, 49(6): 94-97.  DOI: 10.16638/j.cnki.1671-7988.2024.006.017 Abstract ( )   PDF (4046KB) ( )   View of the oil leakage phenomenon near the bolt sealing surface in two places of the durability feedback of a hybrid gearbox bench test, the nonlinear contact finite element simulation analysis of the bolt joint surface here is carried out under two harsh conditions. According to the surface pressure and opening of the simulation joint surface, the rationality of the theoretical sealing surface design is determined, and the sealing performance is improved by changing the processing technology and gluing technology of the joint surface of the box body, the oil leakage test is verified by special loading test, and the oil leakage disappeared. The solution of this problem proves the feasibility of the oil leakage simulation and optimization method of the gearbox sealing surface, and provides a basis for the design and solution of the shell seal. References | Related Articles | Metrics

Select

A Fatigue Simulation Analysis of Vehicle Differential Housing Based on Cumulative Damage Theory GUO Shun 2024, 49(6): 98-101.  DOI: 10.16638/j.cnki.1671-7988.2024.006.018 Abstract ( )   PDF (1847KB) ( )   This study establishes an analysis model of the entire vehicle transmission system through MASTA, and uses the loading torque from the bench test as the input load to obtain the transient stress situation of the differential housing under working conditions. Afterwards, a static analysis is conducted on the finite element model of the differential housing to obtain the stress history during one revolution. Finally, transient fatigue life analysis is conducted in FEMFAT to obtain the cumulative damage and fatigue life of the differential housing. The accuracy and reliability of this simulation method are verified through differential fatigue life bench tests, which can be applied in the design and development of differential housings. References | Related Articles | Metrics

Select

Random Vibration Strength Analysis and Improvement of Automobile Air Conditioning Pipeline YANG Siyuan 2024, 49(6): 102-106.  DOI: 10.16638/j.cnki.1671-7988.2024.006.019 Abstract ( )   PDF (3537KB) ( )   Aiming at the problem of cracking near the weld of air conditioning pipeline of a certain passenger car during the road test, random vibration finite element analysis is carried out on the basis of prestressed modal analysis, and it is found that the weak part of the pipeline is consistent with the road test fracture part. The weld size of the pipeline and joint is optimized by increasing the fillet size of the weld, and random vibration finite element analysis is carried out again. The results show that the maximum stress in the three vibration directions of the fracture weld is reduced by 9.8%, 29.5% and 45.2% respectively, and the maximum stress is reduced from 112.1 MPa to 86.1 MPa, which is lower than the yield limit of the material and meets the strength requirements. The study provides a reference for finite element analysis of random vibration of automotive air conditioning pipelines and strength optimization of welded structures. References | Related Articles | Metrics

Select

Matching Design of Braking Systems for Hybrid Commercial Vehicles ZHANG Jing 2024, 49(6): 107-111.  DOI: 10.16638/j.cnki.1671-7988.2024.006.020 Abstract ( )   PDF (1403KB) ( )   The hybrid commercial vehicle braking system is the process of transforming the fuel braking system into the fuel and power shortage hybrid braking system based on the traditional fuel vehicle. The paper describes in detail the hybrid braking system of compressed air pipeline, electronically controlled air compressor, electronically controlled air dryer, electronically controlled brake valve and pipeline matching design. Through matching design, carrying on the whole vehicle test verification process and application. References | Related Articles | Metrics

Select

Optimization Design of Defrosting Performance of Automobile Air Conditioner Based on Three and One Dimensional Coupling Model CFD Simulation DING Haoqing 2024, 49(6): 112-118.  DOI: 10.16638/j.cnki.1671-7988.2024.006.021 Abstract ( )   PDF (2475KB) ( )   In this paper, the computational fluid dynamics (CFD) analysis method is used to analyze the defrosting performance of a mini-car air conditioner in the design and development stage. The structure of the defrosting duct of the air conditioner is optimized through the steady-state CFD analysis results, and the three-dimensional/one-dimensional coupling simulation is used to conduct the transient analysis of the defrosting of the windshield glass surface under different air conditioner positive temperature coefficient (PTC) configurations, which provides an effective reference for the flow field performance optimization and PTC parameter selection of the air conditioner in the design stage. The results show that the optimized air duct combined with 2.5 kW PTC can meet the requirements of defrosting performance. The defrosting simulation design method provided in this article has certain engineering guidance significance for optimizing the defrosting performance design of air conditioning systems in automotive research and development. References | Related Articles | Metrics

Select

Lightweight Suspension Limit Bracket Design Based on HyperWorks Applied Composite Materials ZHAO Renjie 2024, 49(6): 119-123.  DOI: 10.16638/j.cnki.1671-7988.2024.006.022 Abstract ( )   PDF (2223KB) ( )   The rear suspension of a light truck uses steel plate welded parts and rubber buffer blocks as suspension limiting devices, but the metal parts support is bulky and the height and size are fixed, and the same height support can not be fully adapted to different suspension systems, which is not beneficial to the parts status simplification and vehicle lightweight requirements. In this paper, composite materials are used to optimize the design of suspension bracket through structural improvement. The reliability of the optimized bracket is demonstrated based on HyperWorks finite element analysis and experimental verification, and the cost and weight of the bracket are reduced while the strength performance is satisfied. References | Related Articles | Metrics

Select

Automatic Drawing Design of Automobile Bus Topology Diagram Based on A* Algorithm ZHENG Shengwen 2024, 49(6): 124-130.  DOI: 10.16638/j.cnki.1671-7988.2024.006.023 Abstract ( )   PDF (2160KB) ( )   To adapt to the increasingly complex requirements of modern automobile communication systems, eliminate the hidden dangers of errors caused by manual drawing of automobile bus topology diagram, and improve research and development efficiency, this paper proposes an automatic drawing design scheme of automobile bus topology diagram based on A*algorithm. Firstly, this paper extracts the elements needed for topological graph drawing in actual engineering projects, then combs the automatic drawing process of topological graph, and finally uses A* algorithm to optimize the connection process between nodes and network segments. Based on the actual communication system of a car, compared with the traditional manual drawing, it is verified that this design can significantly improve the drawing efficiency of the automobile bus topology while ensuring clear, beautiful and accurate. References | Related Articles | Metrics

Testing and Experiment

Select

Research on Subjective Evaluation Method of Passenger Car ESC Performance GUO Yinliang 2024, 49(6): 131-136.  DOI: 10.16638/j.cnki.1671-7988.2024.006.024 Abstract ( )   PDF (2085KB) ( )   As active safety technology in vehicles advances swiftly, the implementation of the electronic stability control system (ESC) is becoming increasingly prevalent, significantly contributing to the prevention of vehicular loss of control and enhancing overall automotive safety. This research report introduces the functional of electronic stability systems and compares the test data of different vehicles according to Performance Requirements and Test Methods for Electronic Stability Control Systems (ESC) of Light Vehicles (GB/T 30677－2014). By comparing the experimental results, this article preliminarily establishes a subjective and objective fusion system to evaluate and score the ESC performance of vehicles. The objective is to provide businesses and system manufacturer with a stronger structure to assess these systems. References | Related Articles | Metrics

Select

Comparative Analysis of Three Methods for Testing the Inertia of Car Drive Wheels NI Hao 2024, 49(6): 137-141.  DOI: 10.16638/j.cnki.1671-7988.2024.006.025 Abstract ( )   PDF (1256KB) ( )   This article presents three testing methods for measuring the inertia of car drive wheels based on chassis dynamometer design. The article considers the rotational inertia of the drive wheels as equivalent to translational inertia and treats the inertia system formed by the chassis dynamometer and the drive wheels as a whole. These methods involve simulating inertia and loading resistance using the chassis dynamometer to test the inertia of the drive wheels. The first method is the force difference method, which is derived based on the principle of conservation of momentum. It utilizes the relationship between deceleration time under different loading forces to derive the total inertia of the system and, based on the known loading inertia of the chassis dynamometer, calculates the inertia of the drive wheels. The second method is the multiple mass fitting method, which derives the mechanical relationship during deceleration. It involves conducting deceleration time tests with different simulated inertias of the hub under the same loading resistance. A mathematical model is established to relate the simulated inertia of the hub, deceleration time, and inertia of the drive wheels. The intercept of the model represents the inertia of the drive wheels. The third method is the equivalent mass method, which solves the inertia of the drive wheels based on the mechanical balance equation during vehicle deceleration. These three testing methods enrich the drive wheel testing system and are suitable for testing the inertia of drive wheels in various scenarios. The research results based on the chassis dynamometer experiment indicate that the equivalent mass method has the advantage of higher accuracy in determining the inertia of the drive wheels. The development of these testing methods further enhances the accuracy of chassis dynamometer experiments. References | Related Articles | Metrics

Select

Analysis of the Influence of Fuel Oil Sulfur Content on the Physicochemical Characteristics of Exhaust Particulates LI Tengteng 2024, 49(6): 142-148.  DOI: 10.16638/j.cnki.1671-7988.2024.006.026 Abstract ( )   PDF (1913KB) ( )   The effect of sulfur content in diesel fuel on the morphology, nanostructure, particle size, graphitization degree, surface functional groups and composition of exhaust particles is investigated on a 4.5 L marine auxiliary diesel engine by using three kinds of diesel fuels, which have different sulfur contents. The morphology and nanostructure of exhaust particles are analyzed using transmission electron microscopy (TEM). The graphitization degree of exhaust particles is analyzed by Raman spectrometer. The surface functional groups of exhaust particles are analyzed employing Fourier transform infrared spectrometer. The composition and elemental composition of exhaust particles are analyzed by thermal gravimetric analyzer and plasma emission spectrometer, respectively. Based on the low-powered electron microscopy images, it is found that the exhaust particles is an irregular aggregate structure, which is composed of dozens or even hundreds of spherical or nearly spherical primary particles, and with the increase of fuel sulfur content, the stacking of primary particles becomes more obvious, and the microscopic morphology of exhaust particles changes from chain structure to a more complex agglomerate. Based on high-powered electron microscopy images, it is found that the primary particles perform a typical core-shell structure, and with the increase of fuel sulfur content, the thickness of the amorphous substance at the outer edge of the primary particles and the particle size of the primary particles also increase. Furthermore, with the increase in fuel sulfur content, the research reveals the following findings: in terms of morphology, the average curvature of primary particle crystals increases while the average length decreases; in terms of graphitization, the degree of particle graphitization declines; in terms of composition, the proportion of organic components and S sulfur elements increases. References | Related Articles | Metrics

Process·Materials

Select

Fracture Analysis and Improvement of Servo Motor Shaft in Automotive Industry JIAO Guangsheng 2024, 49(6): 149-154.  DOI: 10.16638/j.cnki.1671-7988.2024.006.027 Abstract ( )   PDF (6710KB) ( )   When the servo motor is in service for three months, the motor shaft suddenly breaks. Through the appearance inspection, low power observation, fracture analysis, metallographic analysis, chemical analysis and mechanical property analysis of the motor shaft, the fracture cause is explored. The results show that the fracture mode of the motor shaft is fatigue fracture. The main causes of fatigue fracture are low hardness of the shaft center leading to insufficient strength, surface mesh ferrite structure defect, and too small chamfer of the cutting groove aggravating stress concentration, and poor heat treatment process is the root cause of insufficient strength. At the same time, the corresponding improvement measures are put forward to prevent such incidents from happening again. References | Related Articles | Metrics

Select

Development and Enhancement of Automotive Dimensional Refinement Technology MAO Jingsong 2024, 49(6): 155-158.  DOI: 10.16638/j.cnki.1671-7988.2024.006.028 Abstract ( )   PDF (2430KB) ( )   With the increasing competition in the automotive industry, the development of new models focusing on quality improvement, cost reduction and delivery acceleration is being optimized. To further enhance the visual perception quality, this paper conducts research on the automotive dimensional refinement technology, establishes relevant processes, and clarifies the focal points of each stage for sub-models. The primary focus is on explaining the evaluation methods for refinement technology during the design stage. These methods involve standardizing evaluation perspectives and dimensions, leveraging software tools like CATIA and VRED for digital modeling and rendering analysis, and utilizing wearable devices for virtual reality simulations. Furthermore, the article summarizes seam division strategies and details specific methods for enhancing delicacy from three dimensions: visual gap, visual surface difference, and appearance R angle. References | Related Articles | Metrics

Select

Optimization of a Processing Process Method of Wheel Hub Ring Hole KANG Haijun 2024, 49(6): 159-162.  DOI: 10.16638/j.cnki.1671-7988.2024.006.029 Abstract ( )   PDF (1525KB) ( )   Wheel hub is an essential key part of the automobile, wheel hub tire bolt ring hole not only high precision requirements, and has a large number, so the processing method and tool selection is directly related to the processing accuracy and efficiency of the wheel hub ring hole. This paper analyzes and optimizes the machining technology of a wheel ring hole by using the method of work step combination, and designs and produces the composite boring cutter independently. On the basis of ensuring the precision of the wheel hub ring hole, the machining efficiency of the wheel hub is effectively improved and the cost is reduced. References | Related Articles | Metrics

Select

Research on the Deformation of Gradient High Scroll Wrap under Thermosolid Coupling LI Annan 2024, 49(6): 163-168.  DOI: 10.16638/j.cnki.1671-7988.2024.006.030 Abstract ( )   PDF (2888KB) ( )   In order to solve a series of problems caused by the deformation of the scroll teeth, a new tooth design scheme－the graduated tooth height scroll tooth is proposed. The tooth head sticking problem is minimized by increasing the tooth height outward annularly, and the effects of gas pressure and temperature fields on the graduated tooth height scroll teeth are simulated by using ABAQUS to establish a finite element model. The results of the study show that the maximum deformation of the center of the scroll tooth is 13 μm under the thermosolid coupling. As the volume of the central compression chamber decreases, the maximum deformation of the scroll teeth increases, which provides a certain theoretical basis for the design of compressor structure and performance optimization. References | Related Articles | Metrics

Select

Transformation of the Main Drive System of CNC Gantry Machining Center DENG Chengfeng 2024, 49(6): 169-172.  DOI: 10.16638/j.cnki.1671-7988.2024.006.031 Abstract ( )   PDF (4713KB) ( )   In this paper, the loss of heavy-duty cutting function and finishing ability before the transformation of the main drive system of the TH42250 CNC gantry machining center is analyzed, and the overall transformation design scheme of the box structure, shaft, gear and assembly is proposed in terms of improving accuracy, strength and materials. Through the processing, assembly and operation of new spare parts, good results are achieved, and success are achieved in terms of operation stability, temperature rise control, processing accuracy, cost control, and maintenance cost savings. The heavy-duty cutting function and machining accuracy of the equipment returned to the factory design level, which could be used for reference in the fault repair of other main transmission systems and the design and development of gearboxes. References | Related Articles | Metrics

Automobile Education

Select

Research on the Teaching Mode of Automobile Structural Performance and Use Based on OBE Concept YUE Hongwei 2024, 49(6): 173-177.  DOI: 10.16638/j.cnki.1671-7988.2024.006.032 Abstract ( )   PDF (1277KB) ( )   The implementation of the results-oriented curriculum teaching mode reform is intended to mobilize students' initiative, enthusiasm and creativity, improve the comprehensive effect of classroom teaching, and further play the role of classroom teaching as the main channel in the professional talent training. Based on the outcome based education (OBE) concept, combined with talent demand, this paper analyzes the current teaching situation of the course Automobile Structure Performance and Use. Centering on the course objectives and graduation requirements, the teaching design is carried out from the aspects of adjusting the teaching content and integrating the course resources, incorporating the course ideology and politics into the teaching content, and increasing the weight of peacetime assessment, so as to provide ideas for the teaching reform of transportation courses. References | Related Articles | Metrics

Select

Discussion on Teaching Reform of 3D interactive Virtual Simulation Experiment of Automobile Construction MA Xipei 2024, 49(6): 178-182.  DOI: 10.16638/j.cnki.1671-7988.2024.006.033 Abstract ( )   PDF (1602KB) ( )   The 3D interactive virtual simulation experiment course of automobile construction is a teaching method that simulates the experimental operation of automobile construction with computer technology. It has the advantages of high efficiency, safety and economy, which is an indispensable part of automobile engineering education. It changes many problems existing in traditional experimental teaching, such as high cost of experimental equipment, difficulty of experimental operation and high safety risk. In order to further improve the teaching effect of automobile construction 3D interactive virtual simulation experiment course, this paper carries out reform and construction in the overall planning of automobile construction 3D virtual simulation experiment course, the combination of teaching content and practical cases, teaching methods and so on, so as to improving students practical skills, application ability and innovation ability. Through continuous improvement and perfection, the virtual simulation course of automobile construction will play an increasingly important role in the education of automobile engineering. References | Related Articles | Metrics

Select

Classroom Teaching Reform and Practice of "Student-centered" Automobile Construction WANG Yanjie 2024, 49(6): 183-187.  DOI: 10.16638/j.cnki.1671-7988.2024.006.034 Abstract ( )   PDF (1555KB) ( )   Based on the concept of China's engineering education certification and the requirements of the ministry of education for "new engineering", with the automobile industry's requirements for talent training quality as the guidance, and in view of the current situation of curriculum construction and problems existing in talent training for transportation majors, the student-centered classroom teaching reform of Automobile Construction is carried out under the guidance of the outcome based education (OBE) concept, exploring and sorting out ideological and political elements, and enriching Based on the concept of China's engineering education certification and the requirements of the ministry of education for "new engineering", with the automobile industry's requirements for talent training quality as the guidance, and in view of the current situation of curriculum construction and problems existing in talent training for transportation majors, the student-centered classroom teaching reform of Automobile Construction is carried out under the guidance of the outcome based education (OBE) concept, exploring and sorting out ideological and political elements, and enriching References | Related Articles | Metrics

Select

Research and Reform of the Deep Integratio Talent Training Mode in IndustryEducation Science and Technology City Based on the "124" Concept WANG Zhongwen 2024, 49(6): 188-193.  DOI: 10.16638/j.cnki.1671-7988.2024.006.035 Abstract ( )   PDF (1299KB) ( )   The adjustment of national economic structure and the rapid development of urban cluster economy have more and more stringent requirements for all-round industrial talents, so it is urgent to deeply promote the integration of production and education. With the continuous release of policy dividends in industry-education integration, exploring the deep integration teaching model of the 124 ("One Center, Two Entities, Four Integrations") industry-education science and technology city is of great significance. The article takes students as the center, with schools and enterprises as the implementing entities, and integrates the four dimensions of "industry+education+technology+ urban cluster" to create an innovative talent development model for the smart automotive industryeducation integration. The research focuses on the innovative mechanisms of industry-education integration, the implementation plans for science and education integration, the cooperation modes for urban clusters, and the operational models of school-enterprise collaboration. With the assistance of artificial intelligence (AI) and digital empowerment, the efficiency and quality of vocational education talent development have been comprehensively improved. References | Related Articles | Metrics

Select

Reform and Practice of Power Battery Control Test Technology Course Ideological and Political Teaching YAN Yalin 2024, 49(6): 194-198.  DOI: 10.16638/j.cnki.1671-7988.2024.006.036 Abstract ( )   PDF (1699KB) ( )   In order to better train students to have the vocational ability required to match the positions of enterprises, the teaching reform and practice are carried out by taking Power Battery Control Test Technology which a professional core course of new energy vehicle technology. The course teaching reform focuses on the classified training, accurate teaching talent training mode, guided by "skilled, standardized and accurate completion of power battery control testing and maintenance work", reconstructs the course content of Power Battery Control Test Technology according to the real project tasks of enterprises, and uses teaching means such as practical training bases inside and outside the school and experiential scenes of "testing workshops". Find out the convergence of ideological and political elements and professional knowledge, internalize safety responsibility in the heart, externalize professional norms in the line, integrate ideological and political elements into the whole teaching process in combination with actual positions of enterprises, so as to truly achieve realize all-round education. Through carrying out the ideological and political teaching reform and practice of this course, it provides certain guiding significance for the teaching reform of other related courses. References | Related Articles | Metrics