順應性機械手指設計

Compliant Robot Finger Design

李政諺(Cheng-Yen Li)

指導教授 ： 陳傳生

元智大學/工程學院/機械工程學系/碩士(2012年)

https://doi.org/10.6838/YZU.2012.00231

摘要

現今機器人與人們的互動將越來越頻繁，機器人與人的安全性考量需要包含在設計概念中。
本論文主旨在以安全性為設計概念出發，使用順應性致動器概念設計一隻三關節兩自由度的被動式順應性機械手指；被動式順應性致動器使用彈簧或其他彈性體做為機構中緩衝吸收衝擊及外力的材料，使機構具有順應外力抵抗衝擊的特點並且有可變剛性的功能。以順應性致動器做為手指的設計概念符合設計上的安全需求。
本文所用的順應性致動器概念為將馬達連接在支點可移動的槓桿的一端，另一端連接在彈簧上。在平衡狀態下，彈簧作用力乘以力臂(R2)等於致動器端所承受的外力乘上力臂(R1)，兩者將會成為一個力矩平衡的狀態。當改變支點位置時兩者力臂(R1，R2)大小也跟著改變，所對應所需要達成平衡狀態的外力大小也會改變，因此達成可變剛性的目的。
最終對設計完的機械手指進行力量及剛性分析，並使用solidworks simulation模擬驗證本手指在不同的剛性設定時受不同外力有不同的偏移量確定有剛性可調之特性，並進一步模擬手指在受到一個具有1470mm/s速度的剛體衝擊後，顯示裝置被動順應性機構之MP joint具有抗衝擊的能力。
本論文設計之機械手指未來可做為人形機械手掌，義肢或是機械夾爪的基礎。

關鍵字

機械手指 ； 順應性 ； 可變剛性

並列摘要

Recently, applications with human-robot interactions increase rapidly. For human-robot interaction, safety becomes an important issue for robotic design.
A passive compliant actuator has a variable stiffness characteristic and it uses a spring or an elastic element to absorb external impact forces. This thesis aims to take safety into account to design a 2 degree of freedom compliant robot finger with three joints by implementing the compliant actuator concept.
The concept of compliant actuator in this article is “pivot movable lever mechanism.” A linear actuator is attached to one side of the lever, and the other side of lever attached to a spring. Changing pivot position means changing the length of lever arm of each side, and it must not be the same for external force exerted on actuator under torque balance condition, so that causes stiffness adjustable characteristic.
The compliant robot finger concept is analyzed and verified by Solidworks simulation. The result shows the compliant finger is able to change the apparent stiffness of a finger joint and to absorb impacts from interactions.
This compliant robot finger design could be extended to build a humanoid robotic hand, prosthetic and robotic gripper.

並列關鍵字

robot finger ； passive compliant ； variable stiffness

參考文獻

[13] 鄭剴元, ”多手指機械手掌設計與控制,” 元智大學,碩士論文,(2008).

[14] 王至丞, ”連桿驅動式機械人手設計,” 元智大學,碩士論文,(2009).

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