本論文介紹能以恆定接觸力處理不同尺寸與勁度物體之夾持器的設計、模擬與實驗過程。當使用夾持器操作不確定尺寸與勁度的物體時，保持適當夾持力是一項具有挑戰性的任務。為了避免夾持行為傷害物體，通常利用力量感測方式直接或間接取得接觸力資訊，回授控制夾持器輸入。定力夾持器的概念在於保持夾持端與物體之間的接觸力為指定的恆定力量，而不必使用感測器與控制方法。以此概念設計出兩種不論物體尺寸與勁度均能產生恆定接觸力的夾持器，第一種夾持器可在一定範圍的輸入旋轉下，透過對稱的彈性機構產生恆定扭力，經過可調整的槓桿臂後形成定力，再傳輸成為恆定夾持力。另一種夾持器則是以定力機構產生恆定力量，再透過靜平衡機構傳輸成為恆定接觸力到夾持端。兩種夾持器均透過公式化的數值計算找到最佳的機構形狀，再與商業軟體模擬相互驗證，並製造定力夾持器原型進行測試實驗。最後期望定力夾持器能可靠有效地應用自動化工廠與手術器械領域，提供安全穩定的夾持操作。

This research presents the design, simulation, and experiment of compliant grippers that can provide a constant gripping force to handle objects of various stiffness and size. Maintaining a proper gripping force is a challenging task of grippers used for manipulating delicate objects with uncertain sizes and stiffnesses. To avoid damage and provide a stable grip of an object, force feedback is often required so that the gripping force can be directly or indirectly regulated. Without using additional sensors and control, the proposed grippers passively maintain a constant contact force between fingertip and an object given a pre-specified force magnitude. Two types of grippers are designed to generate a nearly constant contact force regardless of object stiffness and size. The first gripper consists of a symmetric flexible mechanism that can generate a constant torque regardless of input rotation. The constant torque is converted to a constant force through an adjustable lever arm and then transmitted to fingertips. The other is designed to have a constant input force generated by a constant-force mechanism. Transmitted through a statically balanced mechanism, a constant gripping force is obtained at the fingertip. After a formulation to find the optimal gripper shape, both designs are verified by comparing with simulation results. Prototypes are illustrated with experimental demonstrations. These novel grippers are expected to serve as a reliable alternative for object manipulation.

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