Enabling Technologies for Sensory Feedback in Next-Generation Assistive Devices

人工手臂或假肢是一种技术，可以用来帮助人们在严重受伤导致失去手臂后进行日常生活的基本活动。这些活动可能包括吃饭、洗衣、开门或与朋友握手。如今市场上的许多人工手臂都非常复杂，可以实现单个手指的运动，甚至可以实现手指内部的部分运动，就像天然的手臂和手一样。这些假臂通常是通过感知与假臂相连的其余手臂肌肉的收缩来控制的，允许用户通过弯曲肌肉来操作手臂。然而，人工手臂目前缺少的一个关键方面是反馈感。换句话说，使用者在不看手臂的情况下不知道手臂在哪里，也不知道手有多张开，如果拿起一个精致的物体，也感觉不到它被抓得有多紧。这导致人工手臂使用缓慢和笨拙，并阻止其使用变得真正自然。该项目的目标是开发技术，使下一代辅助设备能够通过增强的感官反馈提供真正自然的控制。我们的长期愿景是为用户提供一种反馈感，再现真实手臂的自然反馈。为了实现这种水平的反馈，我们必须满足两个明确的目标：产生模仿自然手臂和手的人工信号，并提供一种将这些信号传递给假肢使用者神经系统的方法。这些目标将通过以下方式实现：制造新的指尖传感器，使假肢具有真实的触觉，包括压力、剪切和温度；开发一种“虚拟手”，模仿真手产生的神经冲动，给用户一种假手的位置感；设计电极和刺激系统，可以将模拟的神经冲动直接传递到个人的神经系统。在假肢装置中建立这种水平的反馈将使实现比目前可能的更高水平的功能。例如，设备用户可以自然地伸手拿起玻璃杯，同时在谈话中保持目光接触，或者拿起苹果而不会碰伤它。这将推动义肢领域的发展，为义肢使用者提供增强的功能，并减少获得新设备时所涉及的学习时间。

An artificial arm, or prosthesis, is an example of technology that can be used to help somebody perform essential activities of daily living after a serious injury that results in the loss of their arm. Such activities might include eating, washing, opening doors, or shaking hands with a friend. Many artificial arms on the market these days are highly sophisticated, offering individual finger movement, and even movement of segments within a finger, that resemble the natural arm and hand. These prosthetic arms are often controlled by sensing the contractions in the muscles of the remaining arm to which the prosthesis is attached, allowing the user to operate the arm by flexing their muscles. However, one key aspect of artificial arms that is currently missing is the sense of feedback. In other words, the user does not know where the arm is or how wide open the hand is without looking at it, and if a delicate object is picked up, there is no sense of how hard it is being gripped. This leads to slow and awkward use of the artificial arm and prevents its use from becoming truly natural.The goal of this project is to develop technologies that will enable the next generation of assistive devices to provide truly natural control through enhanced sensory feedback. Our long-term vision is for artificial arms that provide the user with a sense of feedback that recreates the natural feedback associated with a real arm. To enable this level of feedback, we must meet two clear objectives: to generate artificial signals that mimic those of the natural arm and hand, and to provide a means of delivering those signals to the nervous system of a prosthesis user. These objectives will be achieved by: building new fingertip sensors to give the prosthesis a realistic sense of touch, including pressure, shear and temperature; developing a 'virtual hand' that mimics the nerve impulses that would be produced by a real hand, giving the user a sense of position of an artificial hand; and designing electrodes and a stimulation system that can deliver the simulated nerve impulses directly to the individual's nervous system.Building this level of feedback into prosthetic devices will enable much higher levels of function to be achieved than is currently possible. Device users would be able to naturally reach out and pick up a glass, for example, whilst maintaining eye contact in a conversation, or pick up an apple without bruising it. This will advance the field of prosthetics, provide enhanced function to prosthesis users and decrease the learning time involved when acquiring a new device.