本文針對一新型手腕機構設計控制器。腕機構具有傾俯(Pitch)及偏擺(Yaw)兩個自由度，有別於傳統機器人使用旋轉馬達及體積大之傳動機構，腕機構使用線性步進馬達及導螺桿，配合曲柄滑塊及5R旋轉機構，實現與人類手腕相近之活動範圍，且無論尺寸及重量皆與人類手腕相當。腕機構中使用撓性耦桿實現共置且互相垂直之雙軸撓性致動。相較於剛性致動，撓性致動具有低機械阻抗、安全性，以及能達成高品質力量控制等優點，被應用於仿生機構、復健機構，以及服務機器人等領域。本文首先討論步進馬達特性，探討步進馬達建模及參數鑑別，說明步進馬達驅動方式，接著討論腕機構運動分析及動力分析，以作為設計控制器時之基礎。控制器設計分成兩部分，分別為力量控制及位置控制，兩種控制器皆透過模擬及實驗進行驗證。本文透過力量控制及位置控制，期許腕機構能應用於服務機器人領域，除了實現定位、移動負載外，同時能與人類及外在環境親和互動。

This research presents the controller design of a novel compliant robotic wrist. Unlike traditional wrist mechanisms that consist of series of rotary motors with bulky gear trains, the proposed design consists of two linear step motors with lead crew to amplify the output force. The linear motions are transmitted to the output pitch and yaw rotations through slider crank and spherical mechanisms. The proposed design simultaneously achieves dexterity and high torque density. The size, range of motion, and weight of the proposed wrist are comparable to those of a human wrist. Inspired by human wrists, the proposed wrist employs two linear compliant couplers to achieve two collocated and perpendicular axes of compliant actuation. Compared with traditional stiff actuation, compliant actuation has lower mechanical impedance, higher safety and can easier achieve high-quality force control. Compliant actuation is commonly used in biomimetic mechanisms, exoskeletons, and service robots. This research first presents the mathematical model and parameter identification of step motors. Next, the static and dynamic models of the proposed wrist are developed. The models serve as the basis of controller design. The presented controller design includes force and position control. The controller performance is verified by comparing experiment and simulation results. Through a prototype demonstration, the wrist is expected to serve as an alternative for applications involving human-robot interaction.

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