Pitch Channel Control of a REMUS AUV with Input Saturation and Coupling Disturbances

Abstract

Abstract:The motion of an underwater vehicle is prone to be affected by time-varying model parameters and the actuator limitation in control practice. Adaptive control is an effective method to deal with the general system dynamic uncertainties and disturbances. However, the effect of disturbances control on transient dynamics is not prominent. In this paper, we redesign the L 1 adaptive control architecture (L1AC) with anti-windup (AW) compensator to guarantee robust and fast adaption of the underwater vehicle with input saturation and coupling disturbances. To reduce the fluctuation of vehicle states, the Riccati-based AW compensator is utilized to compensate the output signal from L1AC controller via taking proper modification. The proposed method is applied to the pitch channel of REMUS vehicle's six Degrees Of Freedom (DOF) model with strong nonlinearities and compared with L1AC baseline controller. Simulations show the effectiveness of the proposed control strategy compared to the original L1AC. Besides, the fluctuation in roll channel coupled with pitch channel is suppressed according to the performances of control tests.

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“…The simulation shows the critical parameters for the hydrodynamic behaviour of the model: the results are given in Table 2 below [73,74,75,76,77,78].…”

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“…Recent innovations [6][7][8][9][10] have extended and improved the nominal system identification resulting in high-confidence mathematically modeling in computer simulations. Such simulations permitted Wu et al [11] to redesign the L1 adaptive control architecture for pitch-control with anti-windup compensation based on solutions to the Riccati equation to guarantee robust and fast adaption of the underwater vehicle with input saturation and coupling disturbances and the approach was applied to the pitch channel alone. Stability was emphasized in the single-channel approach to emphasize dynamic nonlinearities and measurement errors.…”

Autonomous Underwater Vehicle Guidance, Navigation, and Control

“…Recent innovations [6][7][8][9][10] have extended and improved the nominal system identification resulting in highconfidence mathematically modeling in computer simulations. Such simulations permitted Wu et al [11] to redesign the L1 adaptive control architecture for pitch-control with antiwindup compensation based on solutions to the Riccati equation to guarantee robust and fast adaption of the underwater vehicle with input saturation and coupling disturbances and the approach was applied to the pitch channel alone. Stability was emphasized in the singlechannel approach to emphasize dynamic nonlinearities and measurement errors.…”