Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Waterproof Joint Motors and Overall Structural Design for Deep-Sea Electric Manipulators
Xiaohui Hu a,b, Jiawang Chen a,b,*, Hang Zhou a,b , Ziqiang Ren a,b , Peng Zhou a,ba

Hainan Institute, Zhejiang University, Sanya, China
Ocean College, Zhejiang University, Zhoushan, China*Corresponding author: Jiawang ChenbHowever, few underwater manipulators currently have thecapability to perform fine work while the Autonomous
Underwater Vehicle (AUV) is hovering. (Feng, 2019; Zhang, 2009)
Based on the above analysis, the invention of an operational
marine pipeline inspection fine work robot with functions such as
visual guidance is very important to improve the technology levelof marine resources development and utilization and marine
engineering infrastructure.

ABSTRACT.
A deep sea electro-mechanic mounted on an underwater pipeline
monitoring robot is presented and a suitable docking method isdesigned for the carrier underwater robot. Improvements are
made to the motor of the waterproof joint of the robot. The size
and weight of the motor of the waterproof joint were reduced,reducing the water adhesion of the robot when working on theseabed and thus improving the accuracy of the operation.
Underwater simulation experiments were carried out to simulate
the working environment of the robot underwater. By analysing
the effect of water viscous drag on the robotic arm.

MECHANICAL STRUCTURAL
This paper presents a deep-sea electro-mechanic mounted on anunderwater pipeline monitoring robot and designs a suitable
docking method for the structural characteristics of the carrier
robot. This 5-function underwater electric drive manipulator
meets the following technical specifications:
1) Working water depth: ≥400 m
2) Number of functions: 4 (joint) + 1 (hand)3) Elongation: ≥0.65 m
4) The gripper can hold 5 kg heavy objects
The manipulator is mounted on a small AUV for autonomous
underwater operations and adopts the method of electric motordriven drive to meet the requirements of stable operation, fast
response, flexible movement, high precision and low powerconsumption.
Depending on the actual application, a 5-function electricmanipulator is designed for depths of 500 m and has a maximum
load of 10 kg. As shown in Figure 1, such manipulator mainly
consists of large arm, small arm, shoulder, wrist and other devices.

KEY WORDS: Underwater Manipulator, Waterproof ArticulatedMotors.
INTRODUCTION
Deep-sea submersibles are important equipment for exploring theseabed, which can dive to the deep sea and even the deepest partsof the ocean and carry out the corresponding operations with theequipment installed on it. Underwater manipulators are the mostimportant equipment for submersible vehicles to complete
underwater operations and play a vital role in the exploitation ofdeep-sea resources.
Submarine oil and gas transmission pipelines, submarine powertransmission cables and submarine communication cables can becalled submarine pipelines. Depth fixing, breakpoint location,
fault detection and repair of submarine pipelines is anindispensable key link in the field of oil, electricity,communications and other industries. (Xu, 2016) The subsea
pipeline inspection method is divided into three main steps:Determining the type of fault occurring in a pipeline by fault typeanalysis.
Selection of different fault detection methods according to thetype of fault and rough testing of the fault point.
Precise location of pipeline defects or submarine cable faults
using close-range pinpointing methods. (Dong, 2020; Zhang, 2015;Tao, 2009)

Figure 1. Structure of 5-function electric manipulator

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