Backstepping sliding-mode leader-follower consensus formation control of uncertain networked heterogeneous nonholonomic wheeled mobile multirobots

This paper presents a leader-follower consensus formation control method using backstepping sliding-mode control for a group of uncertain, networked heterogeneous nonholonomic wheeled mobile robots (NWMRs), in order to achieve formation keeping and trajectory tracking, respectively. The NWMRs are composed of two kind of wheeled mobile robots, including nonholonomic self-balancing two-wheeled mobile robots (NSBTWMRs) and nonholonomic wheeled differential-driving mobile Robots (NWDDMRs). The dynamic behavior of each NWMR is governed by its second-order dynamic model, and the networked multi-NWMR system is modeled by a directed graph. By using the Lyapunov stability and sliding-mode control theories, one intelligent adaptive, distributed consensus control approach is respectively presented to carry out formation keeping and trajectory tracking in the presence of uncertainties, in order to not only keep all the robots in formation, but also let them track their desired trajectories and maintain them in formation, respectively. Simulations are conducted to show the effectiveness and merits of the proposed methods.