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.

中文翻译：

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具有负压作用板的大坝检查机器人的研制

本文介绍了一种水下机器人的开发，该机器人在通过负压作用板的推进器产生的拉力与大坝表面机械接触的同时进行外观检查。通常，小型轻量的遥控车辆（ROV）具有低功率推进器。就外部干扰而言，它们的定位性能较差。此外，未经训练的操作员很难控制ROV位置以目视检查和检查大坝。安装在推进器上的负压作用板会产生负压，该负压可保持机器人与大坝壁表面之间的机械接触，并确保机器人在大坝表面上稳定运动，以获取清晰的连续图像。如此处所述，我们从理论上研究了负压效应板的特性，并通过实验测量了由压差产生的力。结果表明，带有效应板的推进器的力比仅由推进器提供的额定推力大五倍。基于这些结果，我们设计并开发了带有负压效果板的水下机器人，用于大坝检查。此外，我们在日本三重县Shorenji大坝的水箱中进行了一项试验，并进行了现场测试。实验获得的结果表明，负压有效板可有效地产生足够的力，并能在坝面实现稳定的机器人运动。