遠端抓取任務中，操作者主要依賴視覺資訊判斷夾爪與物體之互動狀態，難以即時感知接觸事件、夾持力大小與釋放狀態，容易造成滑落或過度施力。因此，本研究提出一套基於鐵磁流體音圈致動器之整合式指尖觸覺回饋方法，以單一致動器分時提供準靜態力回饋與事件型振動線索，並應用於機械手臂遠端抓取任務中驗證其可行性。
實驗結果顯示，閉迴路恆流驅動電路於 1 V 至 5 V 步階命令下之穩態相對誤差介於 0.71% 至 1.64%。準靜態力輸出與命令電壓呈線性關係，且各電壓等級之標準差皆小於 0.04 N。感知前測中，8 名參與者對三個力等級之整體辨識率為 84.2%，且誤判主要集中於相鄰力級；接觸線索與釋放線索之整體辨識率為 91.2%，顯示所設計之力回饋與振動線索具有可辨識性。
遠端抓取任務比較僅視覺回饋（V）、視覺加準靜態力回饋（HVf），以及視覺加整合式觸覺回饋（HVi）三種條件。結果顯示，V 條件成功率約為 55.0%，破壞率約為 32.5%；HVf 條件破壞率下降至約 5.0%，但滑落率上升至約 32.5%；HVi 條件成功率約為 80.0%，破壞率約為 5.0%，滑落率約為 15.0%，且施力分布較集中。惟三種條件之成功率差異尚未達統計顯著，(p = 0.18)。整體而言，本研究驗證單一鐵磁流體音圈致動器整合準靜態力與事件型振動線索之可行性，並顯示其具有改善遠端抓取施力控制之潛力。

In remote grasping tasks, operators mainly rely on visual information to judge the interaction between the gripper and the object. However, visual feedback alone cannot directly convey contact events, grasping force, or release status, which may lead to object slip or excessive force. Therefore, this study proposes an integrated fingertip haptic feedback method based on a ferrofluid voice-coil actuator. A single actuator is used to provide quasi-static force feedback and event-based vibrotactile cues, and the proposed method is validated in a robotic remote grasping task.
Experimental results show that the closed-loop constant-current driver achieved a steady-state relative error between 0.71% and 1.64% under 1 V to 5 V step commands. The quasi-static force output showed a linear relationship with the command voltage. In the perceptual pretest, eight participants identified three force levels with an overall accuracy of 84.2%, while the overall identification accuracy of the contact and release vibrotactile cues was 91.2%. These results indicate that the designed force feedback and vibration cues were distinguishable to users.
The remote grasping task compared three feedback conditions: visual feedback only (V), visual feedback with quasi-static force feedback (HVf), and visual feedback with integrated haptic feedback (HVi). The results show that the V condition achieved a success rate of approximately 55.0% and a breakage rate of 32.5%. Under the HVf condition, the breakage rate decreased to 5.0%, but the slip rate increased to 32.5%. Under the HVi condition, the success rate reached approximately 80.0%, with a breakage rate of 5.0% and a slip rate of 15.0%. However, the difference in success rate among the three conditions was not statistically significant according to the Friedman test ((p = 0.18)). Overall, this study demonstrates the feasibility of integrating quasi-static force feedback and event-based vibrotactile cues using a single ferrofluid voice-coil actuator, and suggests its potential for improving grasping force control in remote grasping tasks.

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