Slip reduction method dedicated for autonomous wheeled platforms

Abstract

The strategy for controlling the wheel devices including a slip phenomenon is presented. Using the proposed model of wheel-ground interaction, the method for longitudinal slip reduction requiring oscillating speed and acceleration of the wheel is designed. The partitioned controller is derived considering the forces acting on a wheel. Referring to the available in literature experimental data, the model of permissible tractive force is proposed as a part of solution. The nominal trajectory of slip reduction is defined as the reference signal. The motion controller takes into account the difference between the actual torque and the torque required for slip reduction considering such trajectory. Selecting the control signal for stable slip reduction the final value theorem is applied. The values of controller parameters must be properly chosen. The method was tested using simulations and experiments. For completeness of considerations the lateral slip is shortly discussed. The simplified formula for lateral slip angle is delivered and general equations describing the controller are given.