A Control Strategy for an Autonomous Differential Drive Mobile Robot

The purpose of this research is to develop a control strategy for a differential drive autonomous mobile robot. The robotic task is to move in a straight trajectory in the workspace despite powered by two non-identical electric motors. A developed controller was designed to control the rotational speed of the motors independently in order to achieve a straight trajectory of the motion despite the motor differences. In order to fulfil control limitations, a trajectory control strategy with an inertial measurement unit (IMU) is proposed. This leads to the creation of a Matlab/Simulink model of the robot drive system and IMU, which takes into consideration the mechanical constraints of the robot. In this study, simulations were utilized to evaluate performance of the developed controller in the time domain. The usefulness and effectiveness of the developed control strategy is confirmed by simulation. Simulation results demonstrated that the speeds of the motors can be matched quite well, and difference between the achieved and a straight-line trajectory was within a few centimeters. Furthermore, expected challenges are discussed for the future development.