在外科手術中，內視鏡需要精準定位在醫療器材或者在外科儀器上。通常需要將它們保持在某個位置並手動對其進行準確操作。為此目的，有幾種專用於醫學應用的手臂可以商購，但是，它們依靠會導致殘餘運動和不精確度的關節鎖定功能。已經提出使用靜態平衡機制作為改進。
在目前的工作中，提出了具有五個自由度的機構的靜態平衡。此特定功能允許機制將其固定在某個位置，而不需任何鎖定系統和電動系統。所提出的機構由線性平行四邊形連桿機構和角球解耦連桿機構組成。研究它的運動學，以分析其重力位能。並且設計實施了一些基於拉伸彈簧的特定概念，以產生可精確補償重力位能的彈性位能。此種方法可以節省機械總位能，這是靜態平衡所需要的方式。
在實際上的CAD模型用於對合適的機械參數(例如質量和彈簧附接位置)進行數值識別。製造了靜態平衡機構的原型並且可以成功的展示出來。

In some surgical tasks, such as endoscopy, the accurate positioning of medical tools or surgical instruments is required. It is often required to maintain them in certain position and punctually manipulated them manually. Several passive arms dedicated to medical application are commercially available for this purpose. However, they rely on joint locking features that cause residual motion and inaccuracy. The use of statically balanced mechanism has been proposed as an improvement.
In the present works, the static balancing of a mechanism with five degree of freedom is proposed. This specific feature allows a mechanism to hold it in a certain position without the need for any lock system or motorized system. The proposed mechanism is made of linear parallelogram linkages and angular spherical decoupled linkages. Its kinematics is studied to permit the analysis of its gravitational potential energy. Several specific mechanical concepts based on tension springs are designed and implemented to generate an elastic potential energy that accurately compensate the gravitational potential energy. This method allows the conservation of the mechanism total potential energy, which is required for the static balancing.
A realistic CAD model is used for the numerical identification of the appropriated mechanical parameters, such as the masses and the spring attachment positions. A prototype of the statically balanced mechanism is manufactured. Its static balancing testing is successfully provided.

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