Vision-Based Sensing of External Forces Acting on Soft Robots Using Finite Element Method
Vision-Based Sensing of External Forces Acting on Soft Robots Using Finite Element Method
复制标题
使用有限元方法基于视觉感知作用于软体机器人的外力
DOI：
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复制
发表时间：
2018
影响因子：
5.2
通讯作者：
Christian Duriez
中科院分区：
文献类型：
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作者：
Zhongkai Zhang;Jérémie Dequidt;Christian Duriez
在本文中，我们提出了一种基于视觉测量和有限元模型技术融合的软机器人外力传感框架。采用实时有限元方法建立了机器人的精确力学模型，描述了机器人所受外力与预定义特征点位移之间的关系。利用视觉系统测量了这些特征点在真实机器人上的位置，并与有限元模型中的等效特征点进行了比较。利用比较的位移，通过求解反问题来计算外力的强度。基于建立的有限元方程，我们不仅可以估计外力的强度，而且可以估计外力的位置。提出了一种策略，在几种可能的外力中找到正确的外力位置。在柔性板材和并联柔性机器人上进行了仿真和实验，验证了该方法的有效性。实验研究取得了良好的效果，证明了该方法的有效性。
In this letter, we propose a new framework of external force sensing for soft robots based on the fusion of vision-based measurements and finite element model (FEM) techniques. A precise mechanical model of the robot is built using real-time FEM to describe the relationship between the external forces acting on the robot and the displacement of the predefined feature points. The position of these feature points on the real robot is measured using a vision system and is compared with the equivalent feature points in the finite element model. Using the compared displacement, the intensities of the external forces are computed by solving an inverse problem. Based on the developed FEM equations, we show that not only the intensities but also the locations of the external forces can be estimated. A strategy is proposed to find the correct locations of external forces among several possible ones. The method is verified and validated using both simulation and experiments on a soft sheet and a parallel soft robot (both of them have nontrivial shapes). The good results obtained from the experimental study demonstrate the capability of our approach.