Yang Humphrey, Patel Dinesh K, Johnson Tate, Zhong Ke, Olson Gina, Majidi Carmel, Islam Mohammad F, Zhang Teng, Yao Lining
Morphing Matter Lab, Human-Computer Interaction Institute, Carnegie Mellon University, Pittsburgh, PA, USA.
Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.
Nat Commun. 2025 Jan 16;16(1):719. doi: 10.1038/s41467-024-55591-2.
Compliant mechanisms with reconfigurable degrees of freedom are gaining attention in the development of kinesthetic haptic devices, robotic systems, and mechanical metamaterials. However, available devices exhibit limited programmability and form-customizability, restricting their versatility. To address this gap, we propose a metastructure concept featuring reconfigurable motional freedom and tunable stiffness, adaptable to various form factors and applications. These devices incorporate passive flexures and actively stiffness-changing rods to modify kinematic freedom. A rational design pipeline informs the flexures' topological arrangements, geometric parameters, and control signals based on targeted mobilities, enabling the creation of unitary joints with up to six degrees of freedom. Our demonstrative application examples include a wrist device that has an effective stiffness of 0.370 Nm/deg (unlocked state, 5% displacement) to 2.278 Nm/deg (locked state, 1% displacement) to enable dynamic joint mobility control, a haptic thimble device (2.27-52.815 Nmm at 1% displacement) that mimics the sensation of touching physical materials ranging from soft gel to metal surfaces, and a wearable device composed of multiple joints tailored for the arm and hand to augment haptic experiences or facilitate muscle training. We believe the presented method can help democratize compliant metastructures development and expand their versatility for broader contexts.
具有可重构自由度的柔顺机构在动觉触觉设备、机器人系统和机械超材料的开发中越来越受到关注。然而，现有的设备表现出有限的可编程性和形状可定制性，限制了它们的通用性。为了弥补这一差距，我们提出了一种超结构概念，其具有可重构的运动自由度和可调刚度，适用于各种外形尺寸和应用。这些设备结合了被动挠曲和主动变刚度杆来改变运动自由度。一个合理的设计流程根据目标移动性来确定挠曲的拓扑排列、几何参数和控制信号，从而能够创建具有多达六个自由度的单一关节。我们的演示应用示例包括一个腕部设备，其有效刚度在0.370 Nm/deg（解锁状态，5%位移）到2.278 Nm/deg（锁定状态，1%位移）之间，以实现动态关节移动性控制；一个触觉顶针设备（1%位移时为2.27 - 52.815 Nmm），它模拟从软凝胶到金属表面等各种物理材料的触摸感觉；以及一个由为手臂和手部量身定制的多个关节组成的可穿戴设备，用于增强触觉体验或促进肌肉训练。我们相信所提出的方法有助于使柔顺超结构的开发更加普及，并在更广泛的背景下扩展其通用性。
