The design of time-optimal control for two-wheel driven carts catching a target trajectory

This paper addresses the problem of time-optimal control for mobile robots that have two nonsteerable, independent driven wheels. The overall mission of such a control problem is to drive the mobile robots to reach a target l ocation that is a fixed point or a specified trajectory in a minimal time i nterval. Differing from D. B. Reister, and F. G. Pin, the final speed and a ngular velocity of the mobile robots are not restricted. By using the Pontr yagin maximum principle, it is verified that the time-optimal motions of th e mobile robots are all bang-bang controls with bounded control torque on t he two driven wheels. We illustrate that all optimal controls have at most four switch times. The approaches of solving concrete optimal control laws are provided in this paper. These results are applied to the tracking probl em. (C) 1998 Elsevier Science Ltd. All rights reserved.