A Parallel Control of Four Independently Driven Wheels to Maintain UGV Inverse Dynamics

Abstract

An All-Wheel Drive Unmanned Ground Vehicle (UGV) equipped with individual electric motors for each wheel offers tremendous potential to control the angular velocity for each individual wheel and thus control UGV energy efficiency. The objective of this study is to develop an analytical method for a UGV angular velocity control that is based on inverse longitudinal dynamics in straight line motion to indirectly provide the required torque for each wheel to overcome wheel load torque produced from the stochastic terrain. A stochastic terrain mathematical model was developed and used as a disturbance load in the control algorithm to introduce the on-line (real time) influence different terrain conditions on each wheel of UGV. The control algorithm is based on a developed strategy that utilizes the inverse dynamics approach and provides a wheel with both the specified/required angular velocity and rolling radius. At the same time, the required functional of quality is provided during the control process. Such an approach provides a new way to control unmanned ground vehicle dynamics and vehicle performance by concentrating on the individual power distribution to the drive wheels.