基于混联机构的舰船载液压伺服稳定输送平台关键技术研究

The activities, such as the exploitation of ocean resources, the sea rescues and the navigation of freighters, are conducted by the transportation of the employees of construction maintenance, rescue and navigation from a vessel to the target platform or another vessel. The traditional transportation of employees was conducted by the accommodation ladder or the basket when the vessel arrived and anchored near the target. However, limited by the natural environment of the sea, the transportation is inefficient and even risky. To solve this problem, combining the characteristics of parallel mechanisms and hydraulic servo control technology, a steady shipborne transport platform based on the serial-parallel hybrid mechanisms and controlled by the hydraulic servo technology is proposed. The platform provides the real-time compensation for the vessel motion caused by the stormy waves in the sea. Due to the stable environment relative to the gravitational field, the secure channel is built between the platform and target platform or the vessel. Important investigations are conducted as follows： (1) Aiming at the compensation of the adaptive poses of the vessel carrier as well as the platform with lightweight and mini-type, the optimal design of the mechanisms equipped by the platform is investigated. (2) Based on the sea conditions, the wave spectrum and the structure of the vessel, the predict algorithm of the follow-up poses of the carriers aboard the anchored vessel is investigated. (3) Driven by the multi cylinders of the electrohydraulic servo system, the control algorithm of the motion compensation of the transport platform is investigated. The results are of great significance for the security of the operating employees who are exploring in the ocean.

海洋资源开发、海上救援、货轮导航等活动，需要将施工维护、救生、引航等人员从一艘舰船输送到海上目标浮台或另一艘舰船上。传统人员输送采用乘舰船抵近目标，停泊后攀爬舷梯或吊篮登上目标，受海上自然条件限制，输送过程效率低下且充满风险。为了有效解决这一问题，结合并联机构及液压伺服控制技术特点，本课题提出一种基于串并混联机构的舰船载液压伺服控制稳定输送平台。该输送平台实时补偿海上风浪所致的船体运动，建立相对大地重力场的稳定环境，在输送平台与目标浮台或舰船间搭建人员安全输送通道，并开展以下关键技术研究：（1）以满足舰船载体自适应位姿补偿需求和输送平台小型轻质化为目标，研究输送平台机构的数字化最优设计问题；（2）基于海况海浪谱和舰船载体结构特点，研究停泊舰船载体位姿随动预报算法；（3）基于电液伺服多缸协调驱动，研究输送平台运动补偿控制算法。研究成果将对海洋开发中作业人员安全保障具有重要意义。

本项目以串并混联机构的舰船液压伺服控制稳定输送平台为研究对象，对舰船运动及稳定平台的运动学、动力学及控制系统进行了分析、研究。分析了海浪运动规律，利用海浪谱及船体的幅值响应算子，获得了不同海况下的船体运动。对四级海况下的船体运动，采用AR模型和RBF神经网络模型进行了极短期预报，采用EMD+AR组合模型进行了安稳期预报。在机构运动学方面，对稳定平台进行正运动学求解，提出基于调整步长牛顿法的Stewart并联机构位置正解方法，提高了计算效率、扩大了求解范围。采用多目标优化算法对稳定平台进行机构优化，获得满足给定工作空间且运动学、动力学性能较优的平台机构参数。在机构动力学方面，基于虚功原理建立非惯性系下平台的动力学模型，采用拉格朗日插值法推导了高精度微分公式。针对补偿平台具有一定的时间滞后，容易出现误差波动或操作性能不稳定的情况，研究了基于舰船运动预测的稳定平台模型预测控制方法，提高了平台的快速性与稳定补偿精度。针对平台舷梯靠岸问题，提出了基于双目视觉的舰船输送平台运动控制方法，提高了靠岸效率。完成混联舰船稳定输送平台的加工制作，并完成稳定平台样机的标定。结合商用软件和平台功能需求，构建了系统框架，建立了功能、业务与数据模型，基于C++语言完成了并联机构的数字化设计平台。