Tracking control of a free-ranging automatic guided vehicle

Abstract

A motion control system for a free-ranging AGV (Automatic Guided Vehicle) is developed. The emphasis is on the design and implementation of accurate tracking control. A vehicle of two independent driving wheels is used in this work. There are two DC motors driving the front wheels and a free castor in the rear for balance. A kinematic model based on the errors of motion is established and analyzed. The path tracking controller derived from this model can be used to eliminate the tracking errors. The multivariable control problem is solved by the method of linear quadratic regulator (LQR) of optimal control theory. Results from both the computer simulation and practical experiments are presented, which show the tracking controller has acceptable performance.