Modular formulation for dynamics of multi-legged robots

Dynamic modelling plays a significant role in the design and control of fast-moving multi-legged machines. In this paper, a modular method for formulating the dynamics of multi-legged robots with general leg structures is proposed. Each leg is considered as an individual module, and the whole multi-legged system is treated as a free-floating system with the individual leg module being coupled to a main body. The inertia matrix of the system can then be formulated through combining the inertia sub-matrix of each leg module. It is seen that system dynamic equations having a modular characteristics can be derived using the Lagrange's equations. An algorithm for the inverse dynamic analysis is also included.