Facta Univ. Ser.: Elec. Energ., vol. 16, No. 1, April 2003, pp. 55-65

Optimal Control of a Two-Wheeled Mobile Robot: Simulation for Selecting of the Motors

Milovan Radulović, Dejan Popović, and Novak Jauković

Abstract: This paper presents how a novel simulation package for optimal control based on dynamic programming can be used for selecting the drives once the constraints are known: range of speeds, trajectory (minimum radius for turns), load that will be carried by the mobile robot and its position on the platform (inertial properties of the mobile robot with the load). We calculate the necessary driving torques at the wheels of the mobile robot for various trajectories having a shape of the figure eight within a given time. The simulation uses fully customized dynamic model of the mobile robot that is propelled by two independent wheels and has third non-powered wheel that freely rotates around the vertical shaft to ensure three degrees of freedom. Dynamic programming and the discrete mathematic model allow simulation of the nonholonomic system. We presented in this paper only one possible application, that is, the analysis of three different loads carried along the same trajectory. The simulation clearly shows the relation between the tracking error and required diving torque; thereby, allow selection of the adequate driving motors for a given load and vice versa.

Keywords: Mobile robot, dynamic programing, optimal tracking, driving motors.

4mr.pdf