Study On Handling Stability Control For 12 In-wheel Motor Driving Vehicle

The multi-axes heavy-duty guided missile transport vehicles have complex driving conditions and require high off-road performance and maneuverability.Using in-wheel motor to drive the vehicle has carried on a massive innovation for the traditional vehicle driving technology.While changing the traditional structural parameters of the vehicle,it has introduced more degrees of freedom in driving,so that the vehicle can better respond to various complex road conditions.In this paper,the vehicle steering stability problem of the six-axis in-wheel motor which drives the vehicle independently was studied.Firstly,the dynamics model of a vehicle driven independently by the 12?12 in-wheel motor was established,including a driver model,a steering model,a wheel model,a tire model,a suspension model,and a hub motor model.A six-axis vehicle dynamics model with thirty degrees of freedom was constructed,which can fully and accurately reflect the dynamic characteristics of the vehicle in all degrees of freedom,and demonstrate the coupling characteristics of the movement and force in each direction.The platform is established for the study of the control stability.Secondly,a six-axis vehicle monorail model was established to verify the steady-state and transient stability of the monorail model,and verified the reference yaw velocity and the side-slip angle of the vehicle control model;the yaw velocity and the side-slip angle calculated by the monorail model,as well as the lateral speed calculated by the pedal integral are used as the reference variables to establish the joint control model.Then,a target-control function was established to optimally distribute the target control force and moment which calculated by the upper control model.The yaw moment control model and the torque average distribution model are constructed as a comparative model for stability analysis.Thirdly,the completed vehicle dynamics model was used to analyze the stability of various operating conditions,including the stability of the vehicle in a straight line,the driver’s in-ring steering and the driver’s open-loop steering.The special condition,that the part of the in-wheel motors are damaged was established to verify the anti-interference capability of the control model for stability control.The simulation results showed that the joint control strategy of this paper can effectively follow the path,and the convergence of the phase plan is small.The joint control strategy can control the straight line and steering movement of the vehicle steadily.In the case of partial motor damage,one-axis or one and two-axis motors fail,the vehicle can still follow the target path,but the yaw moment of the vehicle cannot fully follow the target path,the stability of the vehicle is reduced,and there is a possibility of side slippage.When the first,third and fifth axle motors which are all on the left side break down,the vehicle cannot effectively follow the target path.The yaw moment of the vehicle cannot fully follow the target path.During actual driving,the fault of same side motors should be avoided.Finally,based on the V development process of the controller,real-time simulation platform was used.Under the input of the driver,the stability of the control system under different working conditions was verified,and the reliability of the system was verified.