Trajectory Tracking Control of a Differential Wheeled Mobile Robot: a Polar Coordinates Control and LQR Comparison

Wheeled mobile robots (WMR) must be designed in order to achieve good performance in activities such as exploration, navigation, mapping, etc. For the development of the WMR, the type of locomotion and its holonomic and non-holonomic constraints should be considered. Some alternatives of the operational configuration of the robot are differential drive, Ackerman steering, or Omni-directional. In that context, this work uses the differential drive configuration due to its simple mathematical model and low computational cost which allows for easy implementation of several specific tasks. The focus of this work is the implementation of a trajectory tracking control for a differential mobile robot based on polar coordinates where it will be compared to an LQR controller. The controllers based on polar coordinates and LQR were implemented in an experimental prototype of a differential mobile robot where the NI MyRIO embedded hardware and the Labview Software were used. The obtained results of the performance of the differential wheeled mobile robot for the designed controllers are shown and discussed in this paper.