监控式水下机械手及相关技术的研究

水下机械手作为水下机器人通用作业工具得到广泛地应用，目前水下机械手的主要操作方式为主从方式。虽然主从方式具有操作直观，灵活的特点，但难于完成需要精确定位，轨迹控制的水下作用，如海洋石油钻井平台导管架的检查作用。为了扩展水下机器人的作业能力，提高水下作业智能化程度，沈阳自动化所承担国家863课题“水下虚拟遥操作与监控机械手系统”关键技术的研究工作。作者参加了此课题的研究工作，以Schilling水下机械手为研究对象，深入研究机械手的作用功能，对机械手的逆运动学，焊缝空间轨迹规划作了深入的研究，形成本文阐述的主要内容。由于Schilling水下机械手各关节之间的连接参数中存在多个偏距，其运动学逆解不能简单由解析方式给出。机械手进行控制与轨迹规划等操作必须找到一种快速求解的方法。本篇文章得出一种基于信赖域法的机械手运动学逆解算法。由于该算法具有收敛速度快的特点，故可以被应用于在线求解机械手运动学逆解；由于没有直接求解二阶导数，故不存在奇异解的问题。经理论分析和实验证明该方法在解决水下监控机械手在线跟踪水下结构物空间轨迹的技术问题具有较好的效果。作为课题的实际应用背景的导管架焊缝曲面为一复杂的空间曲面。为了实现课题的研究目标，本课题不仅要求解焊缝的轨迹，而且要给出其法线方向。对于这样一个问题，用空间解析几何和微分几何方法是很难求解的，本文给出了一种基于B样条参数曲面及曲面求交的方法，具有速度快，通用性强的优点。

The underwater manipulators manipulators are widely used as the general tools of underwater robotics in underwater tasks. The operational type of underwater manipulators is usually master/slave. It is intuitionistic and simple to operate, but it can't finish the underwater tasks of accurate position locating and tracks controlling. In order to extend the working ability of the underwater manipulators and improve the intelligent level of underwater tasks, the SIA took on the project of "863" whose title is "The Research of Underwater Virtual Remote operation and the Mechanical Manipulator in Supervising Operational Type" The author part in this research of "863" project, and deeply research the function of underwater manipulator' s operational type, the inverse kinematics of mechanical manipulator and the layout of the welding line among ducts. This paper mainly expatiates these topics. Because of the existence of offsets in the Schilling manipulator, the inverse kinematics can't be derived by analytic type. But it is badly needed to solve the inverse kinematics of mechanical manipulator rapidly in this project. The new optimization method brought forward in this paper by the author can be used to solve the inverse kinematics of mechanical manipulator of any number of DOF. This optimization method is based on trust region which convergences to the optimal solution globally. This method is super-linear convergent. It is very efficient which only taskes no more than ten milliseconds in PII 400 computer for general resolution. Because it do not solve the twice-differential coefficient, so the solution is stable. This algorithm was used in this "863" project to solve the inverse kinematics of manipulator, and it performed well. The underwater task in this project is to track welding curves on the pipe of the sea drilling platform. The welding curves are sets of complex surface. Not only the track of welding curve, but also the normal direction of the welding curve needs to be solved. It is very difficult to solve such problem by analytic geometry and differential geometry. A method based on B-Spline parameter surface and surfaces' intersect was given by the author. This method is fast and can be used for similar question.