Development of an Osseo-Magnetic Link for Control of Prosthetic Limb Rotation

描述(申请人提供)：本项目的目标是创建一种直观的控制假体关节旋转的方案，以保持肢体旋转的本体感觉。这样的控制方案将减少控制假肢的认知负担，并允许纳入额外的假肢运动，从而减轻残疾负担。该项目旨在通过开发用于假肢手腕旋转的骨磁连接技术来推进这一目标。通过在残留骨的远端植入永久磁铁，并在周围的假体插槽中植入磁场传感器，将实现手腕旋转的自然控制和本体感觉的保存。通过感知受试者旋转剩余前臂骨骼时磁场分布的变化，可以计算出旋转角度并将其应用于假肢手腕旋转器。前臂完整的本体感觉通路将使使用者直观地知道残骨的旋转，并因此知道假肢手腕的旋转。该项目基于以下目标：1)磁传感器的优化，2)传感算法的优化和3)稳健性测试。具体地说，在这一阶段，我们将研究可用的磁性传感器技术，并选择在灵敏度、功耗和封装尺寸之间提供最佳折衷的传感器。我们还将研究控制算法的改进，目标是开发一种数值稳定和计算简单的方法。最后，我们将研究外部电磁场干扰对样机性能的影响，并在有必要的情况下开发屏蔽方法。 公共卫生相关性：经桡骨(手腕以上)截肢是一种使人衰弱的损伤，会导致严重残疾。该研究项目的目标是开发一种使用磁性链接的跨桡骨假体控制技术：在残留的手臂骨骼中放置一块磁铁，这样一系列传感器就可以跟踪其旋转并控制电动手腕旋转器。这将使用户能够自然、直观地控制假肢手腕的旋转，从而增加假体的功能，减轻使用的精神负担。

DESCRIPTION (provided by applicant): The goal of this project is to create an intuitive control scheme for rotation of a prosthetic joint that preserves proprioception of limb rotation. Such a control scheme would reduce the cognitive burden of controlling the prosthetic limb and allow the incorporation of additional prosthesis movements, thus reducing the burden of disability. This project seeks to advance this goal by developing the technology of an osseo-magnetic link for prosthetic wrist rotation. Natural control of wrist rotation and preservation of proprioception will be achieved by implanting a permanent magnet into the distal end of the residual radius bone, and magnetic field sensors into the surrounding prosthetic socket. By sensing the change in magnetic field distribution as the subject rotates their residual forearm bones, the angle of rotation can be calculated and applied to the prosthetic wrist rotator. The intact proprioceptive pathways of the forearm will allow the user to intuitively know the rotation of the residual bone, and, as a result, the rotation of the prosthetic wrist. This proposed project is based on the following aims: 1) optimization of magnetic sensors, 2) optimization of sensing algorithm and 3) robustness testing. Specifically, during this phase we will research available magnetic sensor technologies and select a sensor that provides the best compromise between sensitivity, power consumption and package size. We will also investigate control algorithm refinements with the goal of developing a numerically stable and computationally simple approach. Lastly, we will investigate the effects of external electromagnetic field interference on prototype performance and develop a shielding approach if it is warranted. PUBLIC HEALTH RELEVANCE: Transradial (above wrist) amputation is a debilitating injury and results in severe disability. The goal of this research project is to develop a control technology for transradial prostheses using a magnetic link: a magnet will be placed in the residual arm bone so that a series of sensors can track its rotation and control a motorized wrist rotator. This will allow the user to naturally and intuitively control the rotation of their prosthetic wrist, thus increasing the functionality of the prosthesis and reducing the mental burden of use.