Powered Knee Prosthesis Incorporating Battery-Capacitor Hybrid

描述（由申请人提供）：目前约有623，000人生活在美国，下肢截肢，每年有30，000例新的经股动脉截肢。最新的商业产品是一种由电动机驱动的假肢膝盖，旨在作为其使用者的综合延伸。这样的膝盖允许使用者更自然地执行诸如爬楼梯或从坐姿站起来的任务，从而减少由补偿运动引起的关节损伤。目前的设备需要每年更换一次可充电电池。电池组的价格为几百美元，这对于动力膝关节假肢的拥有者来说是一笔可观的费用。拟议的项目将减少更换电池的需要，从而使普通公众更负担得起动力膝关节假肢。假肢膝关节需要波动的功率要求，以完全模仿人类膝关节的机械行为。目前，主要使用电池来满足电力需求。电池设计用于连续供电，最好在恒定的工作条件下工作;它们在功率波动的情况下表现不佳，无法有效地处理尖峰高功率需求。Giner公司建议通过设计和演示集成电池/电容器混合电源来优化假肢电源。电容器虽然具有非常低的能量密度，但具有非常高的功率密度。在电池/电容器混合（BCH）中，电容器处理大部分功率尖峰，使电池能够在更恒定的条件下工作。金纳公司的方法是将其先进的全固态电容器与可充电锂聚合物电池结合起来，以提供高能量和功率密度。可充电电池和电容器的组合预期在步态周期期间在特定频率下提供特定的高功率。电池继续满足持续的低功耗要求，而电容器将在每个步态周期期间提供100- 250 ms的峰值功率需求。这种设计将允许电池组在更低和更高的电流水平下工作，从而增加其寿命。不需要高浓度硫酸， 典型的电解电容器的外壳，从而消除了对密封封装的需要。第一阶段将包括：（1）电池测试;（2）潜在BCH电源的计算机建模;（3）电容器单元的设计、制造和测试;（4）BCH电源的电子研究;以及（5）与商业电池组的比较。 公共卫生相关性：电动假肢中的可充电电池需要每年更换。拟议的项目将通过使用电池/电容器混合（BCH）来减少昂贵的电池更换需求，这将使电池组能够在更低和更高的电流水平下工作，从而延长其使用寿命，并使动力膝关节假肢更容易为公众所接受。

DESCRIPTION (provided by applicant): Approximately 623,000 people currently live in the United States with a lower limb amputation, with 30,000 new transfemoral amputations conducted each year. The latest commercial product is a prosthetic knee powered by an electric motor designed to function as an integrated extension of its user. Such a knee allows users to more naturally perform tasks such as climbing stairs or rising from a seated position and thereby reduce joint damage caused by compensatory movements. Current devices require replacing the rechargeable battery once a year. The battery pack costs several hundred dollars and represents a considerable cost for owners of powered-knee prosthetics. The proposed project will reduce the need for battery replacement, thereby making powered-knee prosthetics more affordable to the general public. The prosthetic knee requires fluctuating power requirements to fully emulate the mechanical behavior of the human knee joint. Currently, the power requirements are met primarily using a battery. Batteries are designed for continuous energy supply and are best operated at constant operating conditions; they perform poorly in the presence of power fluctuations and cannot efficiently handle spike high power demands. Giner, Inc. proposes to optimize power supplies for prostheses by designing and demonstrating an integrated battery/capacitor hybrid power source. Capacitors, while having very low energy densities, have very high power densities. In a battery/capacitor hybrid (BCH), the capacitor handles most of the power spikes, allowing the battery to function under more constant conditions. Giner Inc.'s approach will be to incorporate its advanced all-solid capacitor with rechargeable lithium-polymer batteries to provide high energy and power densities. The combination of rechargeable batteries and capacitors is anticipated to offer specific high power under certain frequency during gait cycles. The battery continues to meet ongoing low-power requirements while the capacitor will provide peak power needs for 100-250ms during each gait cycle. This design will allow the battery pack to work under much lower and steadier current level, thereby increasing its lifetime. High- concentration sulfuric acid is not required as in the case of typical electrolytic capacitors, thereby eliminating the need for hermetic packaging. Phase I will include: (1) battery testing; (2) computer modeling of potential BCH power supplies; (3) design, fabrication, and testing of capacitor units; (4) electronic investigation of BCH power supplies; and (5) comparisons with commercial battery packs. PUBLIC HEALTH RELEVANCE: The rechargeable batteries in electric motor-powered prosthetic limbs need replacement on a yearly basis. The proposed project will reduce the need for expensive battery replacement by using a battery/capacitor hybrid (BCH) which will allow the battery pack to work under much lower and steadier current level, thereby increasing its lifetime, and making powered-knee prosthetics more affordable to the general public.