Smart Braid Feedback for the Closed-Loop Control of Soft Robotic Systems
Smart Braid Feedback for the Closed-Loop Control of Soft Robotic Systems
复制标题
柔性机器人系统的智能辫反馈闭环控制
DOI：
10.1089/soro.2016.0056
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发表时间：
2017-09-01
期刊：
影响因子：
7.9
通讯作者：
Remy, C. David
中科院分区：
文献类型：
--
作者：
Felt, Wyatt;Chin, Khai Yi;Remy, C. David
本文通过实验研究了柔性电感收缩传感器在软机器人闭环运动控制中的应用潜力。精确的运动控制对于软机器人系统来说仍然是一项极具挑战性的任务。驱动动力学和环境相互作用的精确模型往往是不可用的。这使得开环控制是不可能的，而闭环控制则缺乏适当的反馈。传统的运动传感器，如线性或旋转编码器，难以适应缺乏离散机械关节的机器人。这些传感器的刚性本质与软系统的理想优势背道而驰。由于真正的软传感器解决方案仍处于起步阶段，迄今为止，软机器人的运动控制一直依赖于基于实验室的传感系统，如运动捕捉、电磁（EM）跟踪或光纤布拉格光栅。在本文中，我们使用了被称为智能辫子的嵌入式柔性传感器，通过电感的变化来感知McKibben肌肉的收缩。我们评估了两个系统的闭环控制：一个旋转关节和一个平面，一个自由度的连续机械手。在旋转关节中，我们提出的控制器补偿了致动器连接中的弹性。Smart Braid反馈允许运动控制，稳态均方根（RMS）误差为[1.5]度。在连续体操纵器中，智能编织反馈能够跟踪所需的尖端角度，稳态RMS误差为[1.25]度。这项工作表明，智能编织传感器可以提供准确的位置反馈，闭环运动控制，适合软机器人系统的现场应用。
This article experimentally investigates the potential of using flexible, inductance-based contraction sensors in the closed-loop motion control of soft robots. Accurate motion control remains a highly challenging task for soft robotic systems. Precise models of the actuation dynamics and environmental interactions are often unavailable. This renders open-loop control impossible, while closed-loop control suffers from a lack of suitable feedback. Conventional motion sensors, such as linear or rotary encoders, are difficult to adapt to robots that lack discrete mechanical joints. The rigid nature of these sensors runs contrary to the aspirational benefits of soft systems. As truly soft sensor solutions are still in their infancy, motion control of soft robots has so far relied on laboratory-based sensing systems such as motion capture, electromagnetic (EM) tracking, or Fiber Bragg Gratings. In this article, we used embedded flexible sensors known as Smart Braids to sense the contraction of McKibben muscles through changes in inductance. We evaluated closed-loop control on two systems: a revolute joint and a planar, one degree of freedom continuum manipulator. In the revolute joint, our proposed controller compensated for elasticity in the actuator connections. The Smart Braid feedback allowed motion control with a steady-state root-mean-square (RMS) error of [1.5]degrees. In the continuum manipulator, Smart Braid feedback enabled tracking of the desired tip angle with a steady-state RMS error of [1.25]degrees. This work demonstrates that Smart Braid sensors can provide accurate position feedback in closed-loop motion control suitable for field applications of soft robotic systems.