Consensus of multiple mobile robot systems with directed topologies and nonuniform time delays

This paper proposes a simple method to solve consensus problems of multi-robot systems with directed topologies and nonuniform time delays. The frequency domain method is applied to a second-order system in which the robots are expected to achieve rectilinear consensus motions. Sufficient conditions are provided for the system: if all the time delays are bounded by a derived value, the nonuniform delays won´t affect the consensus achievement of the system. Simulation examples are provided to illustrate the results.