We proposed and developed a small bionic amphibious spherical robot system for tasks such as coastal environment monitoring and offshore autonomous search and rescue. Our third-generation bionic small amphibious spherical robots have many disadvantages, such as the lack of maneuverability and a small operating range. It is difficult to accomplish underwater autonomous motion control with these robots. Therefore, we proposed a fourth-generation amphibious spherical robot. However, the amphibious spherical robot developed in this project has a small and compact design, with limited sensors and external sensing options. This means that the robot has weak external information collection capabilities. We need to make the real time operation of the robot’s underwater motion control system more reliable. In this paper, we mainly used a fuzzy Proportional-Integral-Derivative (PID) control algorithm to design an underwater motion control system for a novel robot. Moreover, we compared PID with fuzzy PID control methods by carrying out experiments on heading and turning bow motions to verify that the fuzzy PID is more robust and exhibits good dynamic performance. We also carried out experiments on the three-dimensional (3D) motion control to validate the design of the underwater motion control system.

中文翻译：

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新型水下水下机器人三维运动控制的模糊PID算法

我们提出并开发了一种小型仿生水陆两栖球形机器人系统，用于沿海环境监测和近海自主搜索和救援等任务。我们的第三代仿生小型两栖球形机器人具有许多缺点，例如缺乏可操作性和较小的工作范围。这些机器人很难完成水下自主运动控制。因此，我们提出了第四代两栖球形机器人。但是，此项目中开发的两栖球形机器人具有紧凑的设计，传感器和外部传感选项有限。这意味着机器人的外部信息收集功能较弱。我们需要使机器人水下运动控制系统的实时操作更加可靠。在本文中，我们主要使用模糊比例积分微分（PID）控制算法来设计新型机器人的水下运动控制系统。此外，通过对航向和转弯弓箭运动进行实验，我们将PID与模糊PID控制方法进行了比较，以验证模糊PID具有更强的鲁棒性并表现出良好的动态性能。我们还对三维（3D）运动控制进行了实验，以验证水下运动控制系统的设计。