Special issue  

The subject of this work is modeling of single-bodied wheeled mobile robots. In the past, it was shown that the kinematics of each such robot can be modeled by one out of only five different generic models. However, the precise conditions under which a model is the proper description of the kinematic capabilities of a robot were not clear. These shortcomings are eliminated in this work, leading to a simple procedure for model selection and a classification of singularities.

The time optimal path following problem for industrial robots regards the problem of generating trajectories that follow predefined end-effector paths in shortest time possible, taking into account kinematic and dynamic constraints. This paper proposes an approach to deal with arbitrary long geometric paths. Further a method is presented to achieve suitable smooth trajectories for an implementation on a real robot, in an easy way.

In this research the motion planning problem for systems that admit a polynomial description of the system dynamics through differential flatness is tackled by parameterizing the system's so-called flat output as a piecewise polynomial. Sufficient conditions on the spline coefficients are derived ensuring satisfaction of the operating constraints over the entire time horizon and an intuitive relaxation is proposed to tackle conservatism.