Simulation and Control of Nonholonomic Differential Drive Mobile Platforms

Abstract

Abstract This thesis explores the application of non-linear control techniques to an inexpensive robot with limited computing ability. A basis for the kinematic description of the Differential Drive Mobile Robot (DDMR) is presented. The dynamics of wheeled robots are developed. The state space of DDMR platforms is found to be non-linear. A control law, based on a paper by Kanayama, is developed and determined to be bounded by a Lyapunov function and asymptotically stable. Using MATLAB, the entire closed-loop system is modeled with difference equations. Methods for tuning the control gains are explored. A modest prototype robot is constructed using a modest 8-bit processor. Reasonable correlation between the physical robot and the simulated robot is observed. Constraints do not hinder the robot’s ability to successfully implement a non-linear control scheme. The MATLAB simulation and physical robot correlate well. The control law is shown to be practical for inexpensive robotic platforms.