Recently, there has been substantial progress in the mechatronic design and myoelectric control of active prostheses. However, a significant unmet need is the lack of sensory feedback in commercial prostheses for upper-limb amputees. The lack of sensory perception impacts on the control performance and embodiment, determining relatively high rejection rates. Previous research has been conducted to evaluate various non-invasive substitutional sensory channels, mainly to regenerate haptic perception. However, providing sensory channels for stiffness perception has been much less explored. In this short paper, we propose a non-invasive wearable sensory armband, named vibrotactile frequency modulation (V-FM) system. Using the V-FM, we implement a closed-loop myocontrol system with force and stiffness perception. A user study was conducted based on a repetitive two-forced alternative choice discrimination test in six able-bodied participants. The study was designed according to the method of constant stimuli. Results showed that using the V-FM armband, the participants recovered sensation comparable (in terms of difference threshold) to the natural stiffness perception. This demonstrated the potential of the proposed V-FM armband in restoring haptic and stiffness perception non-invasively.

中文翻译：

---

用于恢复力和刚度感知的可穿戴双频振动触觉系统

最近，主动假肢的机电一体化设计和肌电控制取得了实质性进展。然而，一个重要的未满足需求是上肢截肢者的商业假肢缺乏感官反馈。缺乏感官知觉会影响控制性能和实施方式，从而确定相对较高的拒绝率。先前的研究已进行评估各种非侵入性替代感觉通道，主要是为了再生触觉感知。然而，为僵硬感知提供感官通道的探索却少得多。在这篇简短的论文中，我们提出了一种名为振动触觉频率调制 (V-FM) 系统的非侵入性可穿戴感觉臂章。使用 V-FM，我们实现了一个具有力和刚度感知的闭环肌肉控制系统。一项用户研究是基于对六名身体健全的参与者进行的重复的双强迫替代选择歧视测试进行的。该研究是根据恒定刺激的方法设计的。结果表明，使用 V-FM 臂章，参与者恢复的感觉与自然僵硬感相当（在差异阈值方面）。这证明了所提出的 V-FM 臂带在非侵入性恢复触觉和僵硬感知方面的潜力。