Exosystem‐observer approach to H ² control with output regulation constraint

Observer-Based Distributed Fault Detection for Heterogeneous Multi-Agent Systems

“…Running the observers and control law simultaneously, the observers could detect the faulty agent if there occurs a fault, and the distributed control law could also realise COR if no fault occurs. It is worth indicating that if the solution pair (X i , U i ) is not unique, we just need to select one of them to design the control law (7), and design FD observers (15) and (29), where the parameters of FD observers contain the selected solution pairs (X i , U i ). What is more, the designed control law (7) with any chosen solution pair (X i , U i ) will realise consensus control when there exists no faulty agent, and existence of the designed FD observers will also hold under any chosen solution pair (X i , U i ).…”

“…Define y i as the observer feedback information that agent i's observers for FD could utilise, which is designed to contain state x i and compensator state η i of agent i, as well as agent i's neighbours', where agent i's neighbours' compensator state η i are also utilised in control law (7).…”

“…Existence of FD observers just requires c > 0, which is the same as realisation conditions of COR, i.e., control law (7) and observers (15) are able to run simultaneously. What is more, if the remaining follower agents still have paths to the leader after removing the faulty agent, the remaining follower agents could still realise COR.…”

“…For the condition that state information is measurable, run control law (7) and observers (15) for FD.…”

“…Besides homogeneous MAS, research on heterogeneous MAS is also significant. As an effective method to realise cooperative control of heterogeneous MAS, for instance, a network of unmanned aerial vehicles (UAVs) with different dynamics, cooperative output regulation (COR) has attracted intensive research attention during the past decade [3][4][5][6], which was based on output regulation theory, where the influence of mismatched disturbance generated by an exosystem could be completely rejected via converting mismatched forms into matched forms [7]. Specifically, H. Basu and S. Y. Yoon considered the condition that only partial information of an exosystem matrix was accessible to each agent, where a distinct estimator network was proposed to cooperatively estimate the value of the exosystem state [8].…”