Offshore installations e.g.marine transportation, oil platforms, etc., are strongly dependent on sea conditions. To increase the workable time of carrying out these operations, a Stewart platform is installed on a ship to serve as a motion compensation base, and equipment on the base can have the same precision with those on the land-fixed base. Herein, movements of the Stewart platform are influenced by ship motions. Consequently, they present more complicated dynamical characteristics. Besides, uncertainties coming from the load and the hydraulic system may deteriorate system performance. To deal with the aforementioned problems, this paper proposes an adaptive robust dual-loop control scheme. Specifically, a multiple-degree-of-freedom velocity feedforward compensator is proposed to decouple motion disturbance from the base platform. Furthermore, the original dynamics model is transformed into a linearly parameterized form, and adaptive laws are utilized to estimate essential parameters. Then, a command-filtered based adaptive robust controller is developed. Finally, it is rigorously proven that control errors are bounded employing Lyapunov-based analysis, and simulations are included to illustrate the effectiveness of the proposed control scheme.

海上设施，例如海上运输、石油平台等，强烈依赖于海况。为了增加执行这些操作的可工作时间，在船上安装了 Stewart 平台作为运动补偿基地，基地上的设备可以与陆地固定基地上的设备具有相同的精度。在此，Stewart 平台的运动受船舶运动的影响。因此，它们呈现出更复杂的动态特性。此外，来自负载和液压系统的不确定性可能会降低系统性能。针对上述问题，本文提出了一种自适应鲁棒双环控制方案。具体而言，提出了一种多自由度速度前馈补偿器，以从基础平台上解耦运动扰动。此外，将原始动力学模型转化为线性参数化形式，并利用自适应律来估计基本参数。然后，开发了基于命令过滤的自适应鲁棒控制器。最后，使用基于李雅普诺夫的分析严格证明了控制误差是有界的，并包括仿真来说明所提出的控制方案的有效性。