本研究利用拓樸最佳化方法來設計機械利益最大化之自適性撓性夾爪。自適性撓性夾爪為撓性機構的一種，可以適應不同外形、尺寸甚至是不規則形狀之物體，且不會對脆弱與易碎的被夾取物造成損傷。機械利益則是輸出力量與輸入力量的比值，機械利益值越大表示在相同的輸入力量下具有較大的輸出力量，可以承受較大的負載。在拓樸最佳化設計的部分，本研究使用參數化水平集拓樸最佳化方法，此方法以參數化的方式改進了傳統水平集拓樸最佳化方法運算量大的問題，且具有結構邊界較平滑與無灰階元素等優點。本研究以反向機構與夾合機構為例，並分別以機械利益、幾何利益與複合應變能作為撓性機構的目標函數，進行此方法之驗證、比較與討論。本研究並使用了Hinge free方法來避免拓樸最佳化結果產生過細的連接結構，可使結果更為勻稱，並避免應力集中與疲勞破壞。為了加速最佳化流程的收斂速度，本研究提出了一個材料移除方法，在疊代的過程中將靈敏度較低的結構加以移除。在自適性撓性夾爪的設計上，本研究由不同的設計參數與設計方法歸納出五種設計案例，並擬定挑選準則篩選出最合適之自適性撓性夾爪設計後，以3D列印軟性材料的方式進行製作。本研究同時也開發了一個包含了撓性夾爪本體與夾爪致動器之自適性撓性夾爪模組，並將其整合至國產六軸機械手臂，進行不同目標物的夾取實驗。實驗結果顯示本研究所設計的自適性撓性夾爪模組的最大負載為2.5 kg，並可夾取尺寸小於141 mm的未知目標物。此電動撓性夾爪可應用於機器人與自動化產業，並可解決傳統剛性夾取系統無法處理形狀尺寸不固定，且柔軟並容易損傷的目標物之自動化取放問題，有效降低自動化成本並增進生產效能。

This study presents a level set based topology optimization method to design an adaptive compliant gripper with maximum mechanical advantage. The adaptive compliant gripper is a compliant mechanism which can be used in handling of fragile objects with size and shape variations. The mechanical advantage is defined as the ratio of output force to input force. For a same input force condition, a higher mechanical advantage implies a larger output force, which leads to a higher payload for the compliant gripper. A parameterized level set method is used to perform topology optimization, which is with the advantages such as having smoother structural boundaries and a black and white design without gray elements. A hinge free method is used to minimize the de facto hinge problem, and a material removal scheme is proposed to speed up the numerical computation process. The classical benchmark problems in topology optimization literature including inverter mechanism and crunching mechanism are used as the verification examples to demonstrate the effectiveness of the proposed numerical method. The objective functions including mechanical advantage, geometric advantage, and a strain energy based function are used in this study. The proposed method is used to design the compliant gripper. Five analysis cases are performed, and an optimal design is identified according to the design rules and the results from finite element simulation. A compliant gripper module including actuator and 3D printed compliant fingers is prototyped then mounted on a six-axis industrial robot for grasping test. The test results show the developed compliant gripper can grip unknown objects with the size up to 141mm, and the maximum payload is 2.5 kg. The proposed motor-driven compliant gripper can be used to resolve the challenging issue for robotic automation of irregular and fragile objects, as well as to increase the productivity and reduce the cost for industrial automation.

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