Control of FES and an Electric Motor Drive for a hybrid gait neuroprosthesis

 描述（由申请人提供）：功能性电刺激（FES）和动力外骨骼是旨在恢复截瘫患者行走的一些技术。FES可用于通过外部施加低水平重复电流来获得下肢中所需的肌肉收缩。动力外骨骼使用电动机驱动来移动下肢关节。每个人都有局限性。我们的目标是将这两种技术联合收割机结合起来，创造一种混合神经假体，这种假体比基于FES的行走系统或单独的动力外骨骼更有优势。由于改进的扭矩可靠性，混合步行矫形器可以使用更长的时间或更长的距离。此外，在混合神经假体中使用FES可能会提供与其使用相关的治疗益处。具体而言，我们建议设计和评估一种新的自动控制器的混合步行神经假体，是由一个功能性电刺激系统和半动力外骨骼。很少有研究已经进入混合行走神经假体的控制方法的设计和评价。然而，其控制方法的研究是重要的，以确保操作效率，步态稳定性和扭矩的可靠性。在我们的初步研究结果中，我们表明，基于模型预测控制的动态控制分配可以同时控制FES和电动机产生膝盖伸展任务，尽管存在上述挑战。我们还表明，新的控制器可以适应肌肉疲劳的四头肌肌肉，可以维持膝盖伸展运动更长的一段时间。该提案的假设是，与单一的FES系统相比，新的控制器可以在更长的时间内维持肢体运动，并且总体功率需求将低于电动机系统。该提案的具体目的是：（1）在物理上验证模型预测控制（MPC）方法，该方法优化了改进的混合动力腿部伸展机中FES和电动机的扭矩贡献;以及（2）在混合动力行走设备上物理验证MPC方法，以引起脊髓损伤患者的行走。该项目如果成功，将导致一种混合行走矫形器，它将更轻，可以使用更长的时间或更长的距离。此外，在混合神经假体中使用FES将提供治疗益处;例如，电刺激的应用改善了心血管健康并增加了肌肉质量和抗疲劳性。

 DESCRIPTION (provided by applicant): Functional electrical stimulation (FES) and a powered exoskeleton are among some of the technologies that aim to restore walking in individuals with paraplegia. FES can be used to obtain desired muscle contractions in the lower limbs through external application of low-level repetitive electrical currents. A powered exoskeleton uses electric motor drives to move the lower-limb joints. Alone, each has limitations. We aim to combine these two technologies to create a hybrid neuroprosthesis that is more advantageous than an FES-based walking system or a powered exoskeleton alone. Because of improved torque reliability, the hybrid walking orthosis can be used for a longer time or over longer distances. Moreover, the use of FES in the hybrid neuroprosthesis may provide therapeutic benefits associated with its use. Specifically, we propose to design and evaluate a new automatic controller for a hybrid walking neuroprosthesis that is composed of an FES system and a semi- powered exoskeleton. Little research has gone into the design and evaluation of control methods for a hybrid walking neuroprosthesis. However, research on its control methods is important for ensuring operational efficiency, gait stability, and torque reliability. In our preliminary results, we show that a model predictive control-based dynamic control allocation can simultaneously control FES and an electric motor to produce a knee extension task, despite the aforementioned challenges. We also show that the new controller can adapt to muscle fatigue in the quadriceps muscle and can sustain knee extension movements for a longer period of time. The proposal's hypothesis is that the new controller can sustain limb movements for a longer period of time compared to a sole FES system and the overall power requirement will be lower than an electric motor system. The specific aims of the proposal are: (1) To physically validate the model predictive control (MPC) method that optimizes the torque contribution from FES and an electric motor in a modified hybrid leg extension machine; and (2) To physically validate the MPC method on a hybrid walking device to elicit walking in persons with spinal cord injury. The proposed project, if successful, will lead to a hybrid walking orthosis that will be lighter and can be used for a longer time or over longer distances. Moreover, the use of FES in the hybrid neuroprosthesis will provide therapeutic benefits; e.g., application of electrical stimulation improved cardiovascular fitness and increased muscle mass and fatigue resistance.