欲補償一機器手臂的負荷要求，靜平衡機構需提供一非線性扭矩以補償荷重。現有的靜平衡機構中，依靠線性彈簧使用多種原理分析，以產生靜平衡所需之扭矩曲線；靜平衡機構可作為支撐手臂、腿部肌肉強度不足的患者的外骨骼裝置，其需求是體積小且緻密化的設計，與具備良好的活動性能。本文設計一新型靜平衡機構，使其集中於一接頭，體積小適合外骨骼裝置的應用，設計概念是採用兩個線性彈簧，以合成初靜平衡所需的非線性扭矩曲線。建立其最佳化模型，以最大化其所能平衡的荷重，並探討不同參數對其平衡荷重的影響。此外，本研究特別設計一體積小的線性彈簧，能在有限的尺寸內提供大勁度，並探討不同參數對其尺寸的影響；並透過預壓彈簧的方式，可容易地調整靜平衡機構的輸出扭矩大小，以平衡不同荷重。並建立一原型實驗，以證實所提出的靜平衡機構之貢獻。

Compensating the payload weight of a robotic manipulator requires a mechanism that can generate a nonlinear torque curve. Existing gravity-balancing mechanisms (GBMs) rely on linear springs with various principles to generate the required torque profile. To be used as an exoskeleton for supporting a human limb with strength deficiency, a GBM needs to be compact and provide friendly motion. This paper presents the design of a novel GBM that is suitable for shoulder exoskeleton. The idea is to employ two linear springs to synthesize the required nonlinear torque curve. The springs are concentrated on the base joint to avoid possible interference with human motion. An optimization formulation is given to maximize the weight compensation capability. The effects of various parameters on the achievable weight are discussed. The linear springs are specifically designed to generate large stiffness in a limited space. The effects of various parameters on the achievable size are discussed. Low-volume compliant springs are specifically designed to serve as the linear springs so that large stiffness can be generated in a limited space. Through preloading the springs, the GBM can easily adjust its torque curve to match different weights. An illustrative prototype is given with experiment verifications to demonstrate the claimed merits of the proposed GBM.

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[62] Commercial Products, "EquiPois®: DEFY GRAVITY," http://www.equipoisinc.com/
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