This paper presents solutions to reduce the effects of wheel slippage and kinematic model uncertainty on low- level control and odometry of over-actuated wheeled mobile robots. Odometry aims at numerical integration of the robot direct kinematic model, whose errors are in part dues to model uncertainties. A parameter iden- tification can significantly improve the odometry accu- racy. Wheel slippage introduces large positioning er- rors. Therefore, robot control must be as smooth as possible, which is achieved by an approach to build a continuous motion. The last contribution is specific to omnidirectional robots with offset steered wheels. The redundancy property is used to reduce wheel slippage.