Control of Autonomous Underwater Vehicle using Reduced Order Model Predictive Control in Three Dimensional Space

Abstract

The paper investigates the motion control problem of Autonomous Underwater Vehicle (AUV) in three-dimensional space. Here, we consider a non-linear, nonholonomic and highly under-actuated dynamical model of AUV with six degrees of freedom. Because of its higher-dimensional complex model, the traditional model predictive control technique leads to computational complexity and loss of controllability. The paper proposes a novel MPC scheme using reduced dynamical model. In which, the MPC problem to control AUV in vertical and horizontal planes is formulated as independent optimization problems. The proposed scheme reduces higher-dimensional model to two independent time-varying linearized models for controlling motion in vertical and horizontal planes by neglecting weakly coupled dynamics. Further the reduced optimization problem is solved using quadratic programming to achieve trade-off between computational complexity and control effort optimization. The simulation results show the effectiveness of the proposed control scheme which is employed on non-linear model.