Parallel robots based on Handed Shearing Auxetics (HSAs) can implement complex motions using standard electric motors while maintaining the complete softness of the structure, thanks to specifically designed architected metamaterials. However, their control is especially challenging due to varying and coupled stiffness, shearing, non-affine terms in the actuation model, and underactuation. In this paper, we present a model-based control strategy for planar HSA robots enabling regulation in task space. We formulate equations of motion, show that they admit a collocated form, and design a P-satI-D feedback controller with compensation for elastic and gravitational forces. We experimentally identify and verify the proposed control strategy in closed loop.

翻译：基于手性剪切拉胀材料（HSAs）的并联机器人能够利用标准电机实现复杂运动，同时凭借特殊设计的架构超材料保持结构的完全柔顺性。然而，由于刚度变化且耦合、剪切效应、作动模型中的非仿射项以及欠驱动特性，其控制极具挑战性。本文提出了一种面向平面HSA机器人的基于模型控制策略，使其能够在任务空间实现调节控制。我们建立了运动方程，证明其具有协同定位形式，并设计了带有弹性和重力补偿的P-satI-D反馈控制器。通过实验对闭环条件下的所提控制策略进行了辨识与验证。