Abstract: In this paper, control algorithms for kinematically redundant 3-wheeled mobile robots are proposed. One of popular mobile robots in this type is the poly-articulated expandable 3-wheeled planetary rover "Tri-Star3", which was developed by Tokyo Institute of Technology in Japan. Because each wheel of the robot has one kinematic redundancy, the robot is able to make diverse configurations. However, this robot cannot fully utilize the kinematic redundancy because it employs only three actuators and there are some singularities inside the workspace. Thus, it uses discrete control algorithms to control its motion. To enhance the motion capability, a modified wheel mechanism, which has no singularity and is able to utilize the redundancy, is proposed. The performance of this device is compared to that of Tri-Star3.