Xi Yang’s research while affiliated with Peking University and other places

This paper studies consensus problems for multi-agent systems modeled by linear time-invariant systems with external disturbances under a fixed directed communication topology. It is shown that consensus can be achieved if each agent with the same disturbance signals. But the result is different for each agent with different disturbances. In this case, the finite-gain L p consensus is introduced to describe the effects of the external disturbance on the consensus performance. A necessary and sufficient condition for reaching finite-gain L p consensus is presented, and analytic estimation of the L p gain is given. A distributed algorithm is proposed to ensure that the finite-gain L 2 consensus can be reached with a desired L 2 gain. Numerical examples are given to illustrate the given results.

This paper studies robust consensus problem for multiagent systems modeled by an identical linear time-invariant system under a fixed communication topology. Communication errors in the transferred data are considered, and only the relative output information between each agent and its neighbors is available. A distributed dynamic output feedback protocol is proposed, and sufficient conditions for reaching consensus with a prescribed performance are presented. Numerical examples are given to illustrate the theoretical results.

This paper explores robustness properties of second-order leader–follower consensus in which each agent is characterized by a double-integrator. Communication errors in the transferred data and measurement errors are considered and two robust measures are introduced, respectively, to evaluate the effects of two errors on consensus. The robustness properties of leader–follower for each agent with the same in-degree are investigated and some interesting results on robustness analysis of consensus are obtained for cases of each follower with in-degree 1 and in-degree N−1N−1 where NN is the number of agents. Simulations also support the obtained results.