Analytical framework for the smooth manoeuvre of wheeled mobile robots traversing obstacles

The aims of this paper are twofold. The first aim is to employ a vectorial approach to model the dynamics of wheeled mobile robots (WMRs), which need to travel over localized surface irregularities. This approach results in compact vectorial equations which are more easily programmable using a symbolic programming software tool. The second aim is to apply the model in conjunction with temporal trajectory functions to compute the traction-force requirements of WMRs traversing obstacles of specified profiles. This model-based approach provides a more robust framework for the development of active control of the motion of WMRs traversing obstacles. It is demonstrated that, during obstacle traversing, a compromise can be achieved between the minimal times of manoeuvre on the one hand and traction force, inertia load and geometrical properties of WMRs and obstacles on the other. The traction force needed to complete the manoeuvre may change sign, necessitating a switch to a braking action. This shift between the traction mode and braking mode of the actuators can be avoided by an appropriate choice of a minimum time of manoeuvre. This study also provides a basis for the selection of an appropriate manoeuvre time based on prior knowledge of the friction characteristics of a traction surface. © 2004 The Royal Society.