Vibrotactile Feedback for Prosthetic Limbs II

描述（由申请人提供）：通过提供感觉反馈，假肢的功能和用户接受度可以得到显著改善。 我们的目标是开发一种感觉系统，假肢专家可以将其纳入（或改造）到目前可用的肌电手臂。 该系统是非侵入性的，并且基于皮肤上的振动致动器（振动器）的阵列，用于将编码的感觉信息从假肢输入到残肢的皮肤。 动力臂将针对三类感觉信息：抓握力、物体滑动和手腕旋转（即旋前/旋后）或手指张开的跨度。 先前在开发用于感觉替代的振动触觉策略方面的工作表明，这是一种有前途的方法。 该研究在市场上的实施一直受到缺乏振动器的阻碍，这些振动器体积小，功率高，可以提供局部刺激，与相邻单元的串扰很小。 此外，最佳的振动触觉反馈代码要求振动频率和强度是独立的。 可用的振动器（诸如基于手机旋转电机的振动器或基于传统螺线管的振动器）具有振动频率和强度的强相互依赖性。 此外，基于螺线管的振动器仅在其谐振频率下有效。 第一阶段的大部分工作是针对开发和测试一种新的工程方法的致动器，解耦强度从频率。 开发了一种原型致动器和驱动技术，其提供独立的频率和强度，体积小，提供病灶刺激，消耗最小的功率，并且制造成本低。 该原型在几个非截肢者和截肢者身上进行了测试，结果非常好。 该第二阶段项目的目标是为动力假臂用户开发一种感觉反馈系统，以提供可靠、有用的位置、力和滑动信息。 振动致动器将进一步发展成为一种易于制造的、廉价的装置。 这些致动器的直径将小于5个美国硬币的堆叠，重量小于10克，消耗最小的功率;制造成本低;典型操作一年可靠，并且是一次性的。 将为各种假体选择关节位置传感器（例如手腕旋转）和力传感器（例如捏力）。 微处理器将使用第1阶段中演示的新型感觉编码算法将来自假肢传感器的感觉数据转换为适当的致动。 将在10名上肢截肢受试者中对感觉反馈系统进行广泛测试，以：1）优化编码策略; 2）开发软件训练辅助工具; 3）证明系统组件和系统的可靠性;以及4）确定使用感觉系统时假体功能的改善。 与公众健康的相关性：结合感觉反馈可以大大提高假体控制的质量。 对物体接触、抓握力和物体滑动的外围知识将使截肢者在使用假肢时增加信心，并使其能够处理脆弱的物品，如手指食物，握手问候，或提供婴儿或动物护理。 这种生活质量的改善对截肢者很重要。

DESCRIPTION (provided by applicant): The functionality and user acceptance of prosthetic limbs can be substantially improved by providing sensory feedback. The goal is to develop a sensory system which prosthetists can incorporate (or retrofit) into presently available myoelectric arms. The system is non-invasive and based on an array of vibrating actuators on the skin (vibrotactors) used to input coded sensory information from the prosthesis to the skin of the residual limb. Three categories of sensory information will be targeted for powered arms: grasp force, object slippage and either wrist rotation (i.e. pronation/supination) or span of finger opening. Prior work in developing vibrotactile strategies for sensory substitution has shown it is a promising approach. The implementation of that research into the marketplace has been held up by a lack of vibrotactors that are small, power efficient and that can provide local stimulation with little cross-talk to adjacent units. Further, optimal vibrotactile feedback codes require that the vibration frequency and intensity be independent. Available vibrators such as cell phone rotary motor based vibrators or traditional solenoid based vibrators have strong co-dependence of vibration frequency and intensity. Further, solenoid based vibrators are only efficient at their resonant frequency. A substantial portion of the Phase 1 effort was directed towards developing and testing a novel engineering approach to the actuators which de-coupled intensity from frequency. A prototype actuator and driving technique was developed which provides for independent frequency and intensity, is small, provides focal stimulation, consumes minimal power and will be inexpensive to manufacture. This prototype was tested on several non-amputee and amputee subjects with excellent results. The goal of this PHASE 2 project is to develop a sensory feedback system for users of powered artificial arms to provide reliable, useful position, force, and slippage information. The vibration actuators will be further developed into a readily manufacturable, inexpensive device. These actuators will be smaller in diameter than a stack of 5 US dimes, weigh less than 10 grams, consume minimal power; be inexpensive to manufacture; be reliable for one year of typical operation, and disposable. Joint position sensors (eg wrist rotation) and force sensors (eg pinch force) will be selected for various prostheses. A microprocessor will convert sensory data from the prosthetic sensor to appropriate actuations using the novel sensory coding algorithms demonstrated in Phase1. The sensory feedback system will be tested extensively with 10 upper extremity amputee subjects to: 1) optimize the coding strategy; 2) develop a software training aid; 3) demonstrate the reliability of the system components and the system; and 4) determine the improvement in functionality of the prostheses when the sensory system is employed. RELEVANCE TO PUBLIC HEALTH: The incorporation of sensory feedback could greatly improve the quality of prosthesis control. Peripheral knowledge of object contact and grip force and object slippage will allow amputees to have increased confidence when using their prosthesis as well as make it possible to handle fragile items such as finger foods, engage in a hand shake greeting, or provide infant or animal care. Such improvements in quality of life are important for amputees.