Design and Implementation of Nonuniform Sampling Cooperative Control on A Group of Two-Wheeled Mobile Robots

This paper investigates the consensus problem for a group of two-wheeled mobile robots (2WMRs) using nonuniform sampling. The directed and switching communication topologies are considered. The control protocols for the first-order/second-order system dynamics are designed with bounded control gains. The Rotate&Run scheme is proposed to update the vehicles' states: 1) the vehicle calculates its goal orientation and the input of each wheel at the sampling time instants by using the states of itself and the neighbors; 2) the vehicle rotates in place until it aims at the calculated direction; and 3) the vehicle moves forward/backward with the calculated wheel velocities until the next sampling time instant. It is shown that consensus in a group of 2WMRs can be achieved when the switching directed graphs satisfy certain conditions. The convergence analysis of consensus is conducted based on the algebraic graph theory and stochastic matrix analysis. Experiments demonstrate the effectiveness of the proposed methods.