There is a need to develop a methodology to model physically cooperating mobile robots so as to systematically design and analyze such systems. Our approach is to treat the linked mobile robots as a multiple degree-of-freedom object, comprising an articulated open kinematic chain, which is being manipulated by pseudo robots (p-robots) at the ground interaction points. Dynamics of the open chain are computed independently of the constraints, thus allowing the same set of equations to be used as the constraint conditions change, and simplifying
the addition of multiple robots to the chain. The decoupling achieved through constraining the p-robots facilitates the analysis of kinematic as well as force constraints, not possible with direct analysis. We introduce the idea of a ‘tipping cone’, similar to a standard friction cone, to test whether forces on the robots cause undesired tipping. We have carried out static as well as dynamic analysis for a 2-robot cooperation case.
Also, we have demonstrated that introduction of redundant actuation, by an additional third robot, can help in improving the friction requirements. We also present our preliminary ideas for employing this newly designed framework to analyze other interesting multi-body robotic systems.