Nonlinear Guidance Law Design of Autonomous Underwater Vehicles

自主式水下載具非線性導引律設計

陳永裕(Yung-Yue Chen) ； 陸清達(Ching-Ta Lu)

《中國機械工程學刊》 39卷3期 (2018/06) Pp. 319-328

摘要

One novel nonlinear guidance law forguiding autonomous underwater vehicles (AUVs) to track desired waypointsin three-dimensional (3D) space with a nonlinear proportional derivative (PD) control structure is developed in this investigation. This approach can be applied to generate optimal control commands for AUVs operating in ocean environment. The design objective of this investigation is to develop a nonlinear guidance law, which guarantees the stability and convergence of tracking errors in positions and attitudes with respect to the highly coupled AUV's dynamics and kinematics. In general, it is really a difficult mission to treat this nonlinear waypoint-tracking problem of AUVs due to the high nonlinearity and the time-varying property of the controlled AUV'sdynamics. Fortunately, because of the coordinate transformation and selection of the control gain, the mentioned nonlinear waypoint-tracking problem of AUVs can be effectively solved, and apromising waypoint tracking capability can be obtained for AUVs.

關鍵字

Autonomous underwater vehicle (AUV) ； nonlinear guidance law ； waypoint-tracking design ； 3D space ； six degrees of freedom (6 DOF).

並列摘要

此研究針對無人水下載具提出一3D非線性導航設計。此導航設計的特色在於一具全域穩定性質的非線性最佳PD型式導引律於此研究中可被推導出來。針對水下載具導航問題，要求得一具三度空間全域穩定的非線性最佳化導引律相當不容易。因為一高度非線性之偏微分方程的解需先被求出。藉此求出解才有機會進一步建構非線性最佳化導引律。此設計出之非線性最佳化導引律可讓水下載具採最省能量及最短航程的方式航行至任一事先安排之導航點且可保證軌跡誤差為最小。同時水下載具於受控期間之系統的全域穩定性質也可以被保證。