FEEDBACK-CONTROL OF A NONHOLONOMIC UNDERWATER VEHICLE WITH A CONSTANTDESIRED CONFIGURATION

In this article we present a feedback control law that gives exponenti al convergence of a nonholonomic underwater vehicle to a constant desi red configuration. This is achieved using a piecewise smooth feedback control law that is based on previous work on the control of nonholono mic mobile robots in the plane. The kinematic model of the underwater vehicle is given in SE(3) by homogeneous transformation matrices, and attitude deviations are given by Euler parameters. This gives a global description without singularities. It is also shown how controllabili ty of the nonholonomic underwater vehicle can be analyzed in SE(3) wit hout the use of local charts. The inputs of the system are the three a ngular velocity components and the forward velocity.