隨著機器人在水下複雜且高難度作業環境中的應用增強，優於派遣人員執行水下作業，透過日漸進步的遠端操作技術（teleoperation）及自動化（automation），水下機器人具備長時間作業能力、也沒有人類在水下的生理限制，是提高水下作業效率的關鍵利器。水下作業任務的完成則需要精密靈活的機械手臂來執行，因此致動器（actuator）及編碼器（encoder）作為手臂運動感測器，是確保運動的準確度和機械訊息反饋的核心。
本研究提出並驗證了一種新型可拆卸旋轉式磁編碼器，展示了其卓越的精度和在水下應用中的潛力。該編碼器採用霍爾感測器作為感測元件，搭配磁性增量式碼盤旋轉產生訊號，並通過濾波器來增強信噪比。實驗驗證結果表明，該系統具有高定位精度和重複性，能夠精確響應水下旋轉0.1度的波動。考慮到該測量系統的特性，預見其在水下機械臂關節中的應用前景，從而推動水下精密控制技術的進步。

As underwater robots outperform human divers in complex and challenging underwater environments, the advancements in teleoperation and automation technologies allow these robots to maintain extended working hours without the physiological limitations faced by humans underwater. This makes them a crucial tool for enhancing the efficiency of underwater operations. The completion of underwater tasks requires precise and flexible robotic arms, making actuators and encoders, which serve as motion sensors for the arms, essential for ensuring motion accuracy and mechanical feedback.
This study proposes, develops, and validates a novel detachable rotary magnetic encoder, demonstrating its exceptional precision and potential for underwater applications, whether in underwater or aerial environments. The encoder uses Hall sensors as sensing elements to generate signals orthogonal to the incremental disc rotation and employs filters to enhance the signal-to-noise ratio. Experimental validation results indicate that the system has high positioning accuracy and repeatability, capable of precisely responding to fluctuations of 0.1 degrees underwater. Considering the characteristics of this measurement system, its application prospects in underwater robotic arm joints are anticipated, thus promoting advancements in underwater precision control technology.

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