Consensus of Second-Order Multi-Agent Systems with Uncertainties Using Only Position Measurements under a Directed Graph

This paper focuses on the consensus problem for second-order multi-agent systems with parametric uncertainties using only the position measurements under a general directed graph. In order to remove the necessity of velocity measurements, we propose a consensus algorithm for the system without relative velocity measurements, in which the velocity feedback is replaced by a filter based on a passivity approach. Based on an auxiliary variable, the consensus problem of original system is converted into the consensus problem for a double integrator multi-agent system with a vanishing term. The consensus convergence is then analyzed via the Lyapunov stability and input-to-state stability theory.