Minimum-energy cornering trajectory planning with self-rotation for three-wheeled omni-directional mobile robots

Abstract

A minimum-energy cornering trajectory planning with self-rotation algorithm is investigated for three-wheeled omni-directional mobile robots (TOMRs). First, an generalized minimum-energy point-to-point trajectory planning algorithm is studied, which is obtained using Pontryagin’s minimum principle, a practical cost function as the energy drawn from the batteries to motors, and the accurate TOMR dynamic model including actuator dynamics and the Coriolis force. By analyzing the co-state equation, the minimum-energy rotational velocity trajectory is presented in analytic form. Also a novel algorithm for the minimum-energy translational velocity trajectory is investigated. Second, the minimum-energy cornering trajectory planning algorithm with self-rotation is developed. Simulation results show that the minimum-energy cornering trajectory can save energy up to 15.20%compared with the conventional control using trapezoidal velocity profiles, and up to 3.96 % compared with the loss-minimization control using the armature loss as the cost function. Also a resolved-acceleration controller is implemented to show an actual performance.