形狀記憶合金驅動機械手夾之力回授控制

Force Control of a Robot Gripper Featuring Shape Memory Alloy Actuators

李錦龍(Jin-Long Lee)

指導教授 ： 蕭俊祥

國立臺北科技大學/機電學院/機電整合研究所/碩士(2014年)

https://doi.org/10.6841/NTUT.2014.00546

摘要

本研究提出一種新型的機械夾爪機構，我們使用形狀記憶合金作為機械夾爪的致動器，取代一般常用的伺服馬達為致動器的場合。本機械夾爪搭配有壓力感測器，可以回授夾爪力量值，透過模糊滑動控制(Fuzzy Sliding-mode control)，讓夾爪做出適當大小的夾取力量。此外，內部有使用反滑動偵測(anti-slip control)，此控制法則將用來針對不同物重的未知物件，讓夾爪可以自行判斷出力大小而不是預先設定的力量值。全部演算法均內建在Microchip DSP 單晶片控制器中，該晶片可以對浮點數作快速運算，並對模糊滑動控制(Fuzzy Sliding-mode control)演算法提供即時(real-time)的處理。最後，我們將夾取五種不同物重的物件以及易碎易脆物來驗證本演算法的正確性。

關鍵字

模糊滑動控制(Fuzzy Sliding-mode control) ； 形狀記憶合金 ； 力回授控制

並列摘要

In this paper, we present a design of a gripper for a robot arm. Our research brings out a new driven mechanism with shape memory alloy instead of servo motor as our actuator, and also the gripper is equipped with a force sensor inside. The fuzzy sliding-mode method is our control rule, and furthermore there is an anti-slipping control rule to avoid grabbing unknown object with insufficient force. The whole control strategies are integrated into a Microchip dsPIC MCU with DSP core inside which is good at dealing with complicated float-point calculation. Gripper can change grabbing force in real-time based on fuzzy sliding-mode control due to different weight objects. Finally, we grab five different weight objects and some fragile objects with our gripper to verify our control strategy in the experiment.

並列關鍵字

fuzzy sliding-mode control ； shape memory alloy ； force control

參考文獻

[21] 洪邦祥，以肌電訊號辨識之電子手研發， 國立台北科技大學機電整合研究所碩士論文，2012

[22] 林均祺，形狀記憶合金驅動之電子手研發， 國立台北科技大學機電整合研究所碩士論文，2010

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