Tracking control of an articulated intervention AUV in 6DOF using the generalized super-twisting algorithm

Abstract

The articulated intervention AUV (AIAUV) is an underwater swimming manipulator (USM) with intervention capabilities. Station-keeping and trajectory tracking are essential for the AIAUV to be able to move in confined spaces and to perform intervention tasks. In this paper we propose using the generalized super twisting algorithm, which is an extension of the regular super-twisting algorithm, for the trajectory tracking of the joint angles, position and orientation of the base of the AIAUV in 6DOF. Furthermore, we show the ultimate boundedness of the tracking errors. We also demonstrate the applicability of the proposed control law and compare the performance with the regular super-twisting algorithm with adaptive gains.

Tracking Control of an Articulated Intervention Autonomous Underwater Vehicle in 6DOF Using Generalized Super-twisting: Theory and Experiments

“…In [21], the position, orientation and joint angles were considered for the tracking problem, and equally good results were obtained in theory and in simulations. In [20] and [21], a HOSMO had to be used because velocity measurements were unavailable. When using a HOSMO, quaternions cannot be used to represent the system since the HOSMO does not work with a different number of states in position versus velocity.…”

“…It was proven that the tracking errors were ultimately bounded, and the simulation results demonstrated that the proposed control method provided excellent tracking capabilities. The results obtained in [20] were therefore extended to 6DOF in [21]. In [21], the position, orientation and joint angles were considered for the tracking problem, and equally good results were obtained in theory and in simulations.…”

“…The results obtained in [20] were therefore extended to 6DOF in [21]. In [21], the position, orientation and joint angles were considered for the tracking problem, and equally good results were obtained in theory and in simulations. In [20] and [21], a HOSMO had to be used because velocity measurements were unavailable.…”

“…In recent years, SMC has been developed into higher-order SMC schemes that remove the chattering problem. The supertwisting algorithm (STA) with adaptive gains [19] has been tested for the AIAUV in 2DOF and 6DOF in [20] and [21], respectively, because this algorithm has been considered to be the most powerful second-order continuous SMC algorithm. The STA attenuates chattering, and no conservative upper bound on the disturbance gradient has to be considered to maintain sliding because of the adaptive gains.…”

“…GSTA is an extension of STA that provides finite-time convergence in the presence of time-and state-dependent perturbations, which is essential for robust control of the AIAUV. Preliminary results were presented in [24], where we considered the position, orientation and joint angles for trajectory tracking, but we assumed that velocity measurements were available. We thus avoided using a HOSMO, which means that we could use quaternions to represent the system.…”