Multi-agent autonomous target tracking using distance-based formations

Sammanfattning: In this thesis, the problem of cooperative control of a system of autonomous agents for targettracking is studied, with special focus on autonomous surface vehicles and minimizing theenergy usage in the system. By separating the control problem into two different parts, weindependently calculate the coordination scheme of the system using virtual agents withsingle integrator dynamics and design the control of the actual agents to follow the virtual.Two different control strategies are introduced for the coordination scheme with thegoal of making the agents form a regular polygon formation around the target. The firststrategy is based on gradient descent for three agents. A proof of almost global stabilityfor the system is provided, both with and without the target included. As long as theinitial positions of the agents and target are not collinear, the system will asymptoticallyconverge to the desired formation. The second strategy uses a rigid body formation forthe virtual agents, where the most cost efficient pose is found using assignment and leastsquares minimization.The viability of the control strategies are shown through simulation and with implementationin a real system of small autonomous surface vehicles. Successful experimentsare presented from a setting where the target can be both stationary and moving. Theresults from the thesis will be used and further developed in a project centered aroundautonomous tracking of underwater targets, carried out in collaboration between KTH,NTNU Trondheim and LSTS Porto.