Design And Experimental Research Of All-terrain Electric Vehicle

All-Terrain Vehicle are widely used in agriculture,forestry and military fields because of their good traffic and transportation capacity.Due to the harsh driving environment,the vehicle's flexibility and handling stability have become the main factors affecting its performance.A new all-terrain electric vehicle is designed to improve the stability and mobility of all-terrain vehicles at low speed on low-adhesion road surfaces.Compared with traditional internal combustion engine,four-wheel hub-driven all-terrain vehicle has obvious advantages in vehicle motion control and optimization of driving force distribution,and is an important development direction of future atv technology.Based on the self-made four-wheel hub-driven all-terrain electric vehicle as the research object,the research contents are mainly as follows:(1)Aiming at the design target of the all-terrain electric vehicle,the parametric design of the vehicle is carried out.Three-dimensional software Catia was used to conduct three-dimensional modeling for all-terrain electric vehicle,determine the main parameters of the whole vehicle and the selection of the whole vehicle subsystem,and then purchase and process the parts of each subsystem.(2)Considering the influence of the structure characteristics of the frame on the stability of the vehicle,the finite element modeling and modal analysis of the frame are carried out.The three-dimensional model of the frame was imported into the finite element software ANASYS to'build the finite element frame structure model.The modal analysis was carried out according to the design requirements,and the first six orders of elastic modal shape and its natural frequency characteristics of the frame were obtained.Through modal analysis,it can be seen that the structure design of the frame in this paper is reasonable,which provides a theoretical basis for the subsequent structural design and the manufacture of the prototype car.At the same time,the strength of the frame is checked.After the load is applied,the stress and strain cloud diagram of the frame is analyzed,which shows that the all-terrain trolley frame designed in this paper meets the strength requirements.(3)Simulation test was carried out based on the control strategy of steering stability of all-terrain electric vehicle driven by four-wheel hub.The vehicle dynamics model is established,and the steering stability control strategy is designed on this basis,Control strategy adopts hierarchical design,The upper middle yaw torque output is controlled by SMC algorithm,and the lower control is controlled by the torque optimal allocation algorithm which minimizes the tire utilization rate into the optimization objective.(4)The simulation analysis of steering stability of butt pavement and split pavement under double shifting conditions was carried out.In order to verify the correctness of the steering stability control strategy designed in this paper,the joint simulation was conducted by simulink-carsim.The simulation results show that the yaw velocity and the centroid Angle of the vehicle can follow the reference model well on the low-adhesion road surface.(5)By using DSP chip to control the prototype vehicle,the vehicle four-wheel independent drive experiment and the real vehicle experiment of yaw torque control method were carried out.The experimental results show that the steering stability control strategy designed in this paper can be applied to the actual prototype vehicles and can improve the steering stability.