Experimental Studies of the Q Filter Design for a Disturbance Observer for the Balancing Control of a One-Wheel Robot

Abstract

This paper presents the design of Q filters for the disturbance observer(DOB) to balance a one-wheel robot. The one-wheel robot is an under-actuated system so that its control is not easy. To improve the balancing control performance in the DOB configuration, different Q filters are designed and tested. Three different Q filters are tested:QSUB20/SUB, QSUB31/SUB, and QSUB42/SUB and their performances are compared in terms of the disturbance rejection ability and sensor noise immunity to find the best Q-filter. The analysis shows that Q31 can be realized in the DOB structure. Experimental studies were conducted to verify the performance of QSUB20/SUB and QSUB31/SUB filters in the DOB structure and the one-wheel robot was successfully controlled to maintain the balance.