Ease of dynamic modelling of wheeled mobile robots (WMRs) using Kane's approach

This article illustrates the ease of modelling the dynamics of wheeled mobile robots (WMRs) using Kane's approach for nonholonomic systems. For a control engineer, Kane's method offers several unique advantages over Newton-Euler and Lagrangian approaches used in available literature. Kane's method provides a physical insight into the nature of nonholonomic systems by incorporating the motion constraints as part of the derivation. The presented approach focuses on the degrees of freedom and not on the configuration, and this eliminates redundancy. Explicit expressions to compute the dynamic wheel loads needed by tyre friction models are derived. This paper describes a procedure developed to deduce the dynamics of a differentially driven WMR with suspended loads and operating on various terrains. Since Kane's approach provides a systematic modelling scheme, the method proposed in this paper can be easily generalized to model WMRs with various wheel types and configurations and for various loading conditions. The dynamic model is mathematically simple and is suited for real time control applications.