A Geometrically Exact Model for Externally Loaded Concentric-Tube Continuum Robots.
A Geometrically Exact Model for Externally Loaded Concentric-Tube Continuum Robots.
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DOI：
10.1109/tro.2010.2062570
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Webster RJ 3rd
中科院分区：
文献类型：
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作者：
Rucker DC;Jones BA;Webster RJ 3rd
连续体机器人由多个同心的、预弯曲的弹性管组成，可以在与标准手术针相当的直径上提供灵活性。最近基于力学的模型能够准确地描述机器人在自由空间中的曲线，给出预制的管子曲线以及管子底座的线性和角度位置。然而，在实际应用中，当主动套管必须与其环境相互作用或施加可控力时，需要一个考虑外部载荷下变形的模型。在本文中，我们应用几何精确杆理论建立了一个正向运动学模型，该模型精确地描述了由于外部点和/或分布扳手载荷的一般集合而引起的大挠度。该模型可以容纳任意多个管子，每个管子都有一条常规的预成型曲线。它还描述了单个管子的独立扭转变形。给出了点荷载和分布荷载下的试验结果。负载下的平均末端误差为2.91 mm(占机器人总长度的1.5%~3%)，与现有自由空间模型的精度相近。
Continuum robots, which are composed of multiple concentric, precurved elastic tubes, can provide dexterity at diameters equivalent to standard surgical needles. Recent mechanics-based models of these “active cannulas” are able to accurately describe the curve of the robot in free space, given the preformed tube curves and the linear and angular positions of the tube bases. However, in practical applications, where the active cannula must interact with its environment or apply controlled forces, a model that accounts for deformation under external loading is required. In this paper, we apply geometrically exact rod theory to produce a forward kinematic model that accurately describes large deflections due to a general collection of externally applied point and/or distributed wrench loads. This model accommodates arbitrarily many tubes, with each having a general preshaped curve. It also describes the independent torsional deformation of the individual tubes. Experimental results are provided for both point and distributed loads. Average tip error under load was 2.91 mm (1.5%–3% of total robot length), which is similar to the accuracy of existing free-space models.