Shape Memory Alloy Actuated Active Ankle Foot Orthosis

0731087 Elahinia该提案是用于主动踝足矫形器（AAFO）的开发和评估。该装置将填补现有研究中的差距，旨在帮助患有足下垂疾病的个人以及其他相关康复活动。 由于踝关节周围的肌肉活动受损，足下垂的个体无法背屈他们的脚。足下垂的主要原因是神经损伤、脑卒中、脑性瘫痪和多发性硬化。足下垂有两种常见的并发症。首先，在脚跟着地后，脚没有控制，所以它每走一步都会拍打地面。第二个并发症是在挥杆过程中无法清理脚趾。这会导致人在整个挥杆过程中在地面上拖动脚趾，或者通过改变正常的生物力学来补偿。AAFO是一种可穿戴设备，旨在帮助足部下垂患者恢复正常步态。该设备提供了一个控制的力量，以补偿肌肉缺陷，导致的条件。目前，AFO？s使用笨重的执行器，如直流电机和气动执行器，这不允许实用和舒适的步行。在这项研究中，形状记忆合金（SMA）将被用来提供驱动力的AAFO。为此，将进行分析和实验研究，以开发一种轻便舒适的行走装置。SMA在该应用中的主要优势在于生物相容性和极高的力质量比：SMA丝可以提升近80，000倍自身重量。此外，SMA致动器不需要运动部件，这大大降低了设计的复杂性。

0731087ElahiniaThis proposal is for the development and evaluation of an active ankle foot orthosis (AAFO). This device will fill the gap in the existing research aimed at helping individuals with conditions causing foot drop as well as in other related rehabilitation activities. Individuals with foot drop are unable to dorsiflex their foot because of impaired muscle activity around the ankle. The major causes of foot drop are trauma to the involved nerves, stroke, cerebral palsy and multiple sclerosis. There are two common complications from foot drop. First, there is no control of the foot after heel strike, so that it slaps the ground on every step. The second complication is the inability to clear the toe during swing. This causes the person to drag their toe on the ground throughout the swing or compensate through alterations in the normal biomechanics of ambulation. An AAFO is a wearable device that is intended to help normalize the gait of a person with foot drop. The device provides a controlled force to compensate for muscle deficiencies that cause the condition. The current AAFO?s use bulky actuators such as DC motors and pneumatic actuators, which do not allow for practical and comfortable walking. In this research shape memory alloys (SMAs) will be used to provide the actuation force of the AAFO. To this end, analytical and experimental studies will be performed to develop a device that is lightweight and comfortable for walking. The main benefit of the SMAs for this application is biocompatibility and their very high force to mass ratio: an SMA wire can lift close to 80,000 times of its own weight. Furthermore, SMA actuators do not need moving parts, which greatly reduce the complexity of the design.