A Study on General State Model of Differential Drive Wheeled Mobile Robots

This study introduces a novel approach by representing a multi-input-multi-output (MIMO) differential drive wheel mobile robot (DDWMR) using the standard state space representation for the first time. This representation facilitates the application of analysis and control system design techniques to MIMO systems. Specifically, the investigation delves into stability, controllability, observability, input-output interaction, and the relative gain array of the DDWMR model. To demonstrate the concept, the established methodology employs the conventional pole placement controller design technique to formulate a state feedback control law for trajectory tracking in the DDWMR system, utilizing both a nominal and a generalized model. The generalized model incorporates distinct parameters for the left and right motor-wheel systems, unlike the nominal model where they are assumed to be identical. Simulation results highlight that accounting for the asymmetric characteristics through the controller derived from the generalized model yields superior performance compared to the nominal model-based controller. Furthermore, the proposed model can be served as an illustrative platform for evaluating innovative MIMO control methodologies in prospective studies.