A controller-observer combination for a unicycle mobile robot.

We consider the problem of output feedback trajectory tracking with a unicycle mobile robot system. A state-feedback controller for the non-linear error dynamics of the robot is combined with an observer that estimates the ori-entation error based on available trajectory information and measurement of the position coordinates. The derivation and implementation of the resulting controller is given and tested on an experimental mobile robot. Global exponential tracking results [3] of a unicyle mobile robot with coordinates, reference coordinates and error co-ordinates as in figure 1, are obtained by ω = ωr + c1 sinΘe, c1> 0 v = vr + c2xe − c3ωrye, c2> 0, c3> −1 In [1] this output-feedback trajectory tracking controller was extended with an observer under the assumption that one o