IJCAS

In this paper, the author proposes a noble robust control scheme for an underwater-launched high-speed autonomous underwater vehicle (AUV). The proposed controller can rapidly stabilize the AUV during the initial stage of instability after launch. AUVs are typically not stable after launch due to large acceleration, deceleration, and roll torque. By adding a suitable over-define control constraint to the control command, we can obtain simple yet robust control performance using a conventional controller that is designed for normal conditions. Preventing the control effort from being monopolized by a single axis is possible by distributing it along the axes in a predetermined ratio. In addition, by over-defining the total control capacity, it was able to achieve the effect of applying the maximum possible control effort when necessary. Simulation and sea test results show that the proposed control scheme is suitable for controlling an AUV after an underwater launch.

Keywords: Autonomous underwater vehicle, AUV transient control, control allocation, total control capacity.