Dynamics modeling of a mobile manipulator for wheel slip avoidance

For a mobile manipulator consisting of a 4-wheel skid-steering mobile robot with a 7-DOF manipulator, in order to avoid wheel slip caused by unstructured road conditions, the concept of active control is introduced in this paper. By properly changing the configuration of the 7-DOF arm, the vertical forces of the wheels on the road are adjusted. The wheels which are close to slipping should have a larger force applied so as to be able to avoid the slip. In this paper, an estimate model is built to monitor the slipping condition of the wheels. Additionally, the relationship between the arm´s configuration and the vertical force applied on the wheels is also modeled. Finally, those models are verified by experiments on a mobile manipulator.