Novel Variable Stiffness Spring Mechanism: Modulating Stiffness Independent of the Energy Stored by the Spring
Novel Variable Stiffness Spring Mechanism: Modulating Stiffness Independent of the Energy Stored by the Spring
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新颖的可变刚度弹簧机构：独立于弹簧存储的能量调节刚度
DOI：
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
D. Braun
中科院分区：
文献类型：
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作者：
Sung Y. Kim;D. Braun
理论表明，在恒定变形下，线性螺旋弹簧的刚度和储存的能量之间存在线性关系。这种关系意味着在变形时增加螺旋弹簧的刚度在较大变形时需要更多的能量。用于驱动机器人和人类辅助和增强设备的最先进的可变刚度弹簧致动器的特征在于类似的关系：随着弹簧变形而增加刚度会消耗更多的能量，因为弹簧存储了更多的能量。该特征在要求高的任务中对可变刚度弹簧致动施加了明显的基本限制，例如提升更多、跳得更高或跑得更快，因为在所有这些任务中，可变刚度弹簧应该存储相当大量的能量并提供不同的刚度以适应提升中的不同重量、跳跃中的高度和跑步中的速度。在这里，我们提出了一种创新的可变刚度弹簧设计，其中改变刚度的能量成本与弹簧存储的能量无关。新设计的关键元素是一种新型的浮动弹簧，它可以在不改变弹簧储存能量的情况下改变刚度。具有上述特征的弹簧可以为使用更小的电机和更小的电池组的可变刚度机器人驱动和人类增强铺平道路。
Theory suggests a linear relation between stiffness and the energy stored by a linear helical spring at constant deformation. This relation implies that increasing the stiffness of a helical spring upon deformation requires more energy at larger deformations. State-of-the-art variable stiffness spring actuators, used to drive robots and human assistive and augmentation devices, are characterized by a similar relation: increasing stiffness as the spring is deformed costs more energy as more energy is stored by the spring. This feature imposes an apparently fundamental limitation on variable stiffness spring actuation in demanding tasks, such as lifting more, jumping higher, or running faster, because, in all these tasks, the variable stiffness spring should store a considerable amount of energy and provide different stiffness to accommodate different weights in lifting, heights in jumping, and speeds in running. Here, we present an innovative variable stiffness spring design, where the energy cost of changing stiffness is independent of the energy stored by the spring. The key element of the new design is a novel floating spring which changes stiffness without changing the energy stored by the spring. Springs possessing the aforementioned feature could pave the way towards variable stiffness robot actuation and human augmentation using smaller motors and smaller battery packs.
影响因子：
7.8
作者：
Braun, David J.;Chalvet, Vincent;Hogan, Neville
通讯作者：
Hogan, Neville