Positive–Negative Stiffness Actuators
Positive–Negative Stiffness Actuators
复制标题
正负刚度执行器
DOI：
--
复制
发表时间：
2019
影响因子：
7.8
通讯作者：
Abhinav Dahiya
中科院分区：
文献类型：
--
作者：
D. Braun;V. Chalvet;Abhinav Dahiya
顺应性致动器通常被设计成具有可调的正刚度特性，以便在位移时产生恢复力。这些致动器需要两个独立的电机单元或闭环控制来改变其平衡位置和输出刚度。引入负刚度与可调正刚度相结合，可以以意想不到的方式降低复杂性并扩展这些致动器的能力。在本文中，我们提出了一个顺应性的致动器，采用了被动负刚度机制结合一个有效的可调正刚度机制。我们表明，这样的致动器，使开环刚度调制和平衡位置控制，使用一个单一的电机单元，而不是更传统的可变刚度和系列弹性致动器。本文介绍了正负刚度致动器的理论基础，并演示了使用原型正负刚度致动器可实现的低功耗刚度调制和平衡位置控制。
Compliant actuators are typically designed to possess a tunable positive stiffness characteristic in order to generate restoring force upon displacement. These actuators either require two independent motor units or closed-loop control to change both their equilibrium position and output stiffness. The introduction of negative stiffness, in combination with tunable positive stiffness, may reduce the complexity and extend the capability of these actuators in unexpected ways. In this paper, we present a compliant actuator that employs a passive negative stiffness mechanism in conjunction with an effectively tunable positive stiffness mechanism. We show that such actuator enables open-loop stiffness modulation and equilibrium position control using a single motor unit, as opposed to more conventional variable stiffness and series elastic actuators. The paper presents the theoretical foundation of positive-negative stiffness actuators and demonstrates low-power stiffness modulation and equilibrium position control achievable with a prototype positive-negative stiffness actuator.