Development of dam inspection robot with negative pressure effect plate

Abstract

This paper describes the development of an underwater robot that performs visual inspection while making mechanical contact with a dam surface by a pulling force generated from thrusters with negative pressure effect plates. In general, small and lightweight remotely operated vehicles (ROVs) have low‐power thrusters. Their positioning performance is inferior with respect to external disturbances. Moreover, it is difficult for untrained operators to control the ROV position to check and inspect dams visually. A negative pressure effect plate attached to a thruster produces negative pressure that maintains mechanical contact between the robot and a dam wall surface and ensures stable robot motion on a dam surface to acquire clear continuous images. As described herein, we theoretically investigate the negative pressure effect plate characteristics and experimentally measure the force generated by the pressure difference. Results show that the force of a thruster with the effect plate is five times greater than the nominal thrust force provided by the thruster alone. Based on those results, we designed and developed the underwater robot with the negative pressure effect plates for dam inspection. Moreover, we conducted an experiment in a water tank and a field test at Shorenji Dam, Mie‐prefecture, Japan. The experimentally obtained results indicated that the negative pressure effective plate is effective at generating sufficient force and at realizing stable robot motion on the dam surface. Results demonstrate that the developed robot acquired clear images of the dam surface continuously with no sophisticated operator or controller.

Study on the Optimal Design for Cavitation Reduction in the Vortex Suction Cup for Underwater Climbing Robot

“…In recent years, underwater climbing robots have been extensively developed so as to replace humans to complete some dangerous and hazardous underwater operations, which include cleaning, maintenance, and inspection of bridges [1,2], dams [3][4][5], ship hulls [6][7][8] and so on. During the research of underwater climbing robots, choosing which kind of suction method is one of the main points that researchers should consider [9,10].…”

Integrated Inspection Robotic System for Spherical Tanks: Design, Analysis and Application

“…To ensure the safety and stability of wall-climbing robots at work, sufficient adsorption capacity is essential. In different working environments, different adsorption methods will be selected, such as negative pressure  *Correspondence: xswang@seu.edu.cn 1 College of Mechanical Engineering, Southeast University, Nanjing, 211189, China 2 Special Equipment Safety Supervision Inspection Institute of Jiangsu Province, Nanjing, 210036, China adsorption [1][2][3], bionic adsorption [4][5][6], thrust adsorption [7,8] and magnetic adsorption [9][10][11][12]. Permanent magnet adsorption is used for metal walls, which can provide a large adsorption force and does not require external energy consumption.…”

Support and Positioning Mechanism of a Detection Robot inside a Spherical Tank

“…The adsorption capacity is the basic ability of wallclimbing robots. At present, a variety of adsorption methods have been applied to wall-climbing robots, mainly including negative pressure adsorption [1][2][3][4][5][6], permanent magnet adsorption [7][8][9][10][11][12][13][14][15], thrust adsorption [16,17], and bionic adsorption [18,19].…”