This paper presents a coordinating and stabilizing control law for a group of underwater vehicles with unstable dynamics. The coordinating law is derived from a potential that only depends on the relative configuration of the underwater vehicles. Being coordinated,the group behaves like one mechanical system with symmetry,and we focus on stabilizing a family of coordinated motions,called relative equilibria. The stabilizing law is derived using energy shaping to stabilize the relative equilibria which involve each vehicle translating along its longest(unstable) axis without spinning,while maintaining a relative configuration within the group. The proposed control law is physically motivated and avoids the linearization or cancellation of nonlinearities.
This paper considers the stable coordination problem of two vehicles equipping with internal moving mass actuators.The coordinating and stabilizing control are derived by energy shaping. The proposed method is physically motivated and avoids cancelation or domination of nonlinearities.
Fan Wu~(a) and Zhiyong Geng~(b) The State Key Laboratory for Turbulence and Complex Systems,Peking University,Beijing 100871,China
This paper studies the problem of coordinated motion generation for a group of rigid bodies.Two classes of coordinated motion primitives,relative equilibria and maneuvers,are given as building blocks for generating coordinated motions.In a motion-primitive based planning framework,a control method is proposed for the robust execution of a coordinated motion plan in the presence of perturbations.The control method combines the relative equilibria stabilization with maneuver design,and results in a closeloop motion planning framework.The performance of the control method has been illustrated through a numerical simulation.
