Accurate Synchronised Position Cross-Coupling Motion Controller for Two-Wheel Mobile Robot

The position accuracy of current mobile robots that are driven by independent motors has not been yet achieved to full satisfaction due to the difference in the angular positions of motor rotors that is caused by external and internal disturbances. Thus, an Accurate Synchronised Position Cross-Coupling Motion Controller (ASPC-CMC) for a Two-Wheel Mobile Robot that guarantees zero steady state and zero transient response errors is proposed in this paper to achieve higher accuracy in the robot desired position. Previous CrossCoupling controllers are based on the consideration of only internal disturbances by using only feed-back signals to correct the system speed errors. The technique presented in this paper is based on the consideration of both internal and external disturbances by employing feed-back and feed-forward signals at the same time to generate an error position corrective signal to improve the accuracy in mobile robot desired position. The proposed technique has been mathematically modelled, analysed and simulated by using Digital Signal Processing (DSP) and MATLAB-SIMULINK tools. Simulation results verify the theoretical analysis and show that the suggested technique is robust and yields zero transient response and zero steady state errors. Hence, the proposed technique has improved the accuracy of the mobile robot desired position, for straight or curve of motion, even with the existence of continuous internal and external disturbances that affect both motor control loops. Key-Words: Position Cross-Coupling motion control, Mobile robot, DSP, BLDC Motor.