School of Biomedical Engineering, Indian Institute of Technology (BHU), Varanasi, 221005, India.
Phys Eng Sci Med. 2021 Mar;44(1):229-241. doi: 10.1007/s13246-021-00972-w. Epub 2021 Jan 19.
Persons with upper-limb amputations face severe problems due to a reduction in their ability to perform the activities of daily living. The prosthesis controlled by electromyography (EMG) or other signals from sensors, switches, accelerometers, etc., can somewhat regain the lost capability of such individuals. However, there are several issues with these prostheses, such as expensive cost, limited functionality, unnatural control, slow operating speed, complexity, heavyweight, large size, etc. This paper proposes an affordable transradial prosthesis, controlled by the muscular contractions from user intention. A surface EMG sensor was explicitly fabricated for capturing the muscle contraction information from the residual forearm of subjects with amputation. An under actuated 3D printed hand was developed with a prosthetic socket assembly to attach the remaining upper-limb of such subjects. The hand integrates an intuitive closed-loop control system that receives reference input from the designed sensor and feedback input from a force sensor installed at the thumb tip. The performance of the EMG sensor was compared with that of a traditional sensor in detecting muscle contractions from the subjects. The designed sensor showed a good correlation (r > 0.93) and a better signal-to-noise ratio (SNR) feature to the conventional sensor. Further, a successful trial of the developed hand prosthesis was made on five different subjects with transradial amputation. The users wearing the hand prototype were able to perform faster and delicate grasping of various objects. The implemented control system allowed the prosthesis users to control the grasp force of hand fingers with their intention of muscular contractions.
上肢截肢者由于活动能力丧失，面临严重问题。通过肌电图（EMG）或传感器、开关、加速度计等发出的其他信号来控制的假肢，可以在一定程度上恢复这些个体丧失的能力。然而，这些假肢存在一些问题，如昂贵的成本、有限的功能、不自然的控制、操作速度慢、复杂性、重量大、尺寸大等。本文提出了一种经济实惠的经桡骨假肢，通过用户意图产生的肌肉收缩来控制。专门制造了一个表面肌电传感器，用于从截肢者的残肢前臂捕获肌肉收缩信息。开发了一个欠驱动的 3D 打印手，带有假肢套接组件，以连接这些截肢者的剩余上肢。手集成了一个直观的闭环控制系统，该系统从设计的传感器接收参考输入，并从安装在拇指尖端的力传感器接收反馈输入。将 EMG 传感器的性能与来自受试者的肌肉收缩的传统传感器进行了比较。设计的传感器与传统传感器具有良好的相关性（r>0.93）和更好的信噪比（SNR）特征。此外，在五个不同的经桡骨截肢的受试者上成功进行了开发的手部假肢的试验。佩戴手部原型的用户能够更快、更精细地抓取各种物体。所实现的控制系统允许假肢使用者通过肌肉收缩的意图来控制手部手指的抓握力。
