Development of underwater electric manipulator based on interventional autonomous underwater vehicle (AUV)

Abstract

In applications such as marine rescue, marine science, archaeology, and offshore industries, autonomous underwater vehicles (AUVs) are frequently used for survey missions and monitoring tasks, with most operations being performed by manned submersibles or remotely operated vehicles (ROVs) equipped with robotic arms, as they can be operated remotely for days without problems. However, they require expensive marine vessels and specialist pilots to operate them. Scientists exploring oceans are no longer satisfied with the use of manned submersibles and ROVs. There is a growing desire for seabed exploration to be performed using smarter, more flexible, and automated equipment. By improving the field operation and intervention capability of AUVs, large-scale and long-range seafloor exploration and sampling can be performed without the support of a mother ship, making it a more effective, economical, convenient, and rapid means of seafloor exploration and sampling operations, and playing a critical role in marine resource exploration. In this study, we explored the integration technology of underwater electric robotic arms and AUVs and designed a new set of electric manipulators suitable for water depths greater than 500 m. The reliability of the key components was analyzed by finite element analysis and, based on the theory of robot kinematics and dynamics, simulations were performed to verify the reliability of the key components. Experiments were conducted on land and underwater, trajectory tracking experiments were completed, and the experimental data in air and water were compared and analyzed. Finally, the objectives for further research on the autonomous control of the manipulator underwater were proposed.

摘要

目的

1. 以水下轻量化水下电动机械臂为研究对象,探索水下电动机械臂和自主水下航行器(AUV)的集成技术,设计一套全新的适用于500 m以上水深的水下机械臂。2. 提高AUV的现场操作干预能力和自主作业能力,为海底探测取样作业提供更加有效、经济、方便、快速的手段,在海洋资源探测中发挥更大的作用。

创新点

1. 以水下轻量化水下电动机械臂为研究对象,探索水下电动机械臂和AUV的集成技术,设计了一款全新的适应AUV搭载的水下电动机械手。2. 该水下电动机械手的密封方式借鉴了深海液压系统的工作原理,采用压力补偿的方式提升电动机械手本身的耐压性和防水性,提升了电动机械手的适用水深和水下工作的可靠性。

方法

1. 基于机器人运动学与动力学理论,进行仿真验证,并搭建水下电动机械手实验平台。2. 进行陆上和水下的实验,完成轨迹的跟踪实验,并对水上水下和仿真实验的数据进行对比分析,得到水下电动机械手的轨迹跟踪精度,以验证该机械手的运行精度。

结论

1. 在匀加速/减速过程中,机械手关节的运行更加稳定;在从匀减速到停止的过渡阶段有微量的过冲;在匀速运动过程中,关节角度跟踪不稳定,从波动幅度来看,误差范围约为0.01 rad。2. 通过进一步分析机械手致动器的运动轨迹误差可以得出,机械手在空气中的绝对跟踪误差峰值约为18 mm,而在水下约为14 mm;机械手在水下的末端运动精度比在水中高,匀速时产生的振动幅度也比在空气中小得多。3. 要提高机械臂系统的性能,需要设计更精确的控制系统;进行流体力学分析,还需要搭载配备视觉系统的AUV,以便在水下环境和实际海洋环境中进行下一步的自主操作实验。