Myoelectric signal source separation for prosthetic control

本研究的重点是在肘部以下截肢（或先天性缺陷）的个体的背景下，腕部和手的功能性置换。这几乎占了截肢者总数的三分之二。对于那些有上肢缺陷的人，目前可用的假肢功能有限。这在很大程度上是由于缺乏可由用户传递给设备的控制信息。近年来，通过监测多个部位的肌电信号，并使用先进的信号处理来确定预期的运动，在解读用户意图方面取得了重大进展。申请人已经证明，可以使用模式识别方法以高可靠性控制手腕和手的功能。虽然这代表了一个重大的进步，但模式识别只允许在给定的时间内激活一个函数。这需要用户一次操作一个关节；如果一个任务需要多个关节，这些关节必须按顺序完成。很明显，这不是一个人使用完整肢体的方式。这项研究有望同时独立控制多个关节，为假肢装置提供自然、协调的运动。这将通过结合源分离方法和逆建模来解决前臂肌肉的活动来完成。通过确定作为手和手腕操作“原动力”的单个肌肉的活动水平，可以独立控制每个关节。以自然、协调的方式控制手和手腕功能的能力将代表假肢控制的巨大增强。

This research focuses on the functional replacement of the wrist and hand, in the context of an individual who has an amputation (or congenital deficiency) below the elbow.  This represents almost two-thirds of the amputee population.   For those with upper limb deficiencies, currently available prosthetic limbs offer limited function.  This is due, in large part, to the lack of control information that can be delivered to the device by the user.  Significant advances have been made in recent years in interpreting a user's intent by monitoring the myoelectric signal at multiple sites, and using advanced signal processing to determine the intended motion.  The applicants have demonstrated that it is possible to control wrist and hand function with high reliability using a pattern recognition approach.   Although this represents a significant advance, pattern recognition allows only one function to be actuated at a given time.  This requires a user to manipulate one joint at a time; if a task requires multiple joints, these must be done in sequence.  Clearly this is not how one uses an intact limb.  This research promises simultaneous and independent control of multiple joints to deliver natural, coordinated motion to prosthetic devices.  This will be accomplished using a combination of source separation methods and inverse modeling to resolve the activity the forearm muscles.  By determining the level of activity of individual muscles which act as the "prime movers" in hand and wrist manipulation, each joint may be controlled independently. The ability to control hand and wrist function in a natural, coordinated manner will represent a tremendous enhancement in prosthetic control.