Gollob Samuel Dutra, Park Clara, Koo Bon Ho Brandon, Roche Ellen T
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States.
Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, United States.
Front Robot AI. 2021 Mar 3;8:606938. doi: 10.3389/frobt.2021.606938. eCollection 2021.
In this paper, we present a generalized modeling tool for predicting the output force profile of vacuum-powered soft actuators using a simplified geometrical approach and the principle of virtual work. Previous work has derived analytical formulas to model the force-contraction profile of specific actuators. To enhance the versatility and the efficiency of the modelling process we propose a generalized numerical algorithm based purely on geometrical inputs, which can be tailored to the desired actuator, to estimate its force-contraction profile quickly and for any combination of varying geometrical parameters. We identify a class of linearly contracting vacuum actuators that consists of a polymeric skin guided by a rigid skeleton and apply our model to two such actuators-vacuum bellows and Fluid-driven Origami-inspired Artificial Muscles-to demonstrate the versatility of our model. We perform experiments to validate that our model can predict the force profile of the actuators using its geometric principles, modularly combined with design-specific external adjustment factors. Our framework can be used as a versatile design tool that allows users to perform parametric studies and rapidly and efficiently tune actuator dimensions to produce a force-contraction profile to meet their needs, and as a pre-screening tool to obviate the need for multiple rounds of time-intensive actuator fabrication and testing.
在本文中，我们提出了一种通用建模工具，用于使用简化的几何方法和虚功原理预测真空驱动软致动器的输出力曲线。先前的工作已经推导了用于对特定致动器的力-收缩曲线进行建模的解析公式。为了提高建模过程的通用性和效率，我们提出了一种完全基于几何输入的通用数值算法，该算法可以针对所需的致动器进行定制，以快速估计其力-收缩曲线以及各种几何参数组合的情况。我们确定了一类线性收缩真空致动器，其由刚性骨架引导的聚合物外皮组成，并将我们的模型应用于两个这样的致动器——真空波纹管和流体驱动折纸启发式人工肌肉——以展示我们模型的通用性。我们进行实验以验证我们的模型可以利用其几何原理预测致动器的力曲线，并与特定设计的外部调整因素进行模块化组合。我们的框架可以用作通用设计工具，允许用户进行参数研究，并快速有效地调整致动器尺寸以产生满足其需求的力-收缩曲线，还可以用作预筛选工具，从而无需进行多轮耗时的致动器制造和测试。
