Multiple Mobile Robotic Formation Control Based on Differential Flatness

There are numerous applications whereby multi-robot cooperative systems are more useful than using a single robot. However, for a cooperative system to implement tasks accurately, an effective formation controller is essential. This paper presents a formation control method that is based on Differential Flatness theory to improve coordination control of a model-based cooperative multiple mobile robotic system. The Differential Flatness characterisation of the team robots allows for the linearization of the system to a stable linear equivalent. Also, the Flatness theory has the advantage of simplifying the trajectory planning task because nonlinear differential equations can be converted to algebraic equation, hence there is no need to integrate robot model differential equations. Each robot is represented by a reduced number of variables which greatly reduces the computational cost especially when dealing with multiple robots that can otherwise entail solving large robotic model differential equations. Simulations using a formation of three differentially driven mobile robots in a leader-follower formation, is used to validate the cooperative formation controller proposed in this paper.