Force interaction and allocation for the legs of a walking vehicle

Force is often used in the control of the legs of a walking machine to allow a vehicle to adapt to terrain irregularity. However, interactions in force among the legs have the capability of causing control system instabilities if not properly treated. Different criteria for allocating forces to the legs of a walking machine are considered, properties of force-induced instability modes are studied, and the plan of hybrid control allocated by legs as a means of avoiding these force interaction modes without requiring an excessively high control frequency is introduced.