Despite technological advancements, upper limb prostheses still face high abandonment/rejection rates due to limitations in control interfaces and the absence of force/tactile feedback. Improving these aspects is crucial for enhancing user acceptance and optimizing functional performance. This pilot study, therefore, aims to understand which sensory feedback in combination with a soft robotic prosthetic hand could provide advantages for amputees, including performing everyday tasks. Tactile cues provided are contact information, grasping force, degree of hand opening, and combinations of this information. To transfer such feedback, different wearable systems are used, based on either vibrotactile or force stimulation in a non-invasive modality matching approach. Five volunteers with a trans-radial amputation controlling the new prosthetic hand SoftHand Pro performed a study protocol including everyday tasks. The results indicate the preference of amputees for a single, i.e. non-combined, feedback modality. The choice of appropriate haptic feedback seems to be subject and task-specific. Furthermore, in alignment with the participants' feedback, force feedback, with adequate granularity and clarity, could potentially be the most valuable feedback among those presented. Finally, the study suggests that prosthetic solutions should be preferred where amputees are able to choose their feedback system.

中文翻译：

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上肢假肢中的触觉反馈：对经桡动脉截肢者比较不同触觉方式的初步研究

尽管技术进步，但由于控制界面的限制和缺乏力/触觉反馈，上肢假肢仍然面临很高的废弃/拒绝率。改善这些方面对于提高用户接受度和优化功能性能至关重要。因此，这项试点研究旨在了解哪些感官反馈与软机器人假手相结合可以为截肢者提供优势，包括执行日常任务。提供的触觉提示包括接触信息、抓握力、手张开的程度以及这些信息的组合。为了传递这种反馈，使用了不同的可穿戴系统，基于非侵入性模态匹配方法中的振动触觉或力刺激。五名进行经桡动脉截肢手术的志愿者控制新型假手 SoftHand Pro 执行了一项研究方案，其中包括日常任务。结果表明截肢者更喜欢单一的（即非组合的）反馈方式。适当的触觉反馈的选择似乎是针对特定主题和任务的。此外，根据参与者的反馈，具有足够粒度和清晰度的力反馈可能是所提出的反馈中最有价值的反馈。最后，研究表明，在截肢者能够选择反馈系统的情况下，应首选假肢解决方案。