CAREER: A Prosthetic Elbow with Network of Soft and Modular Thermo-Active Actuators for Mobility Impaired Patients

在美国，大约有1500万行动不便的人需要帮助才能移动肢体。辅助机器人已经被提出用来帮助行动不便的人。现有的辅助机器人执行器仅限于刚性执行器和柔性执行器。刚性执行器是强大的，但可能会造成伤害。软执行器可以更安全，但不像刚性执行器那样强大、便携或反应迅速。使用热来刺激驱动的软执行器是便携的，可以是强大的。然而，对于许多康复应用来说，他们的反应可能太慢了。这个NSF学院早期职业发展(CALEAR)项目试图通过开发用于康复的基于Peltier的灵活软执行器的新型网络来克服这些挑战。该项目将为未被充分代表的预科、本科生和研究生以及残疾学生提供研究机会。PI的长期目标是创造一种轻便、便携、柔软但反应迅速和强大的可穿戴康复技术。为了实现这一目标，本项目旨在优化开发和控制模块化热激活软执行器网络，使其具有前所未有的康复应用性能。每个执行器由两个模块组成，其中由于液-气相变导致的体积急剧变化导致每个模块内柔性管的轴向膨胀和收缩。在模块之间放置柔性涂层，以吸收来自一个模块的热量，并将热量传递给另一个模块。一个模块加热时膨胀，另一个模块冷却时膨胀。该提案的研究目标是：(1)了解控制执行器和网络操作的潜在的多物理(电-热-机械)，(2)创建一个框架，用于优化网络性能并确定执行器的设计参数对性能的影响，(3)开发一种通用和健壮的控制方案，以及(4)展示建议的网络执行器用作假肢肘部传动系统的能力。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

There are about 15 million mobility impaired people in the United States who need assistance to move their limbs. Assistive robots have been proposed to help people with mobility impairments. Existing actuators for assistive robots are limited to rigid actuators and soft actuators. Rigid actuators are powerful but may cause injury. Soft actuators can be safer, but not as powerful, portable, or responsive as their rigid counterparts. Soft actuators that use heat to stimulate actuation are portable and can be powerful. However, their response can be too slow for many rehabilitation applications. This NSF Faculty Early Career Development (CAREER) project attempts to overcome these challenges by developing novel networks of flexible Peltier-based soft actuators designed for rehabilitation. The project will provide research opportunities to underrepresented pre-college, undergraduate, and graduate students and to students with disabilities.The PI’s long-term goal is to create a wearable rehabilitation technology that is lightweight, portable, and soft but also quick to respond and powerful. Toward this goal, this project aims to optimally develop and control networks of modular thermo-active soft actuators with unprecedented properties for rehabilitation applications. Each actuator is composed of two modules, in which dramatic volume change due to the liquid-gas phase transitions leads to the axial expansion and contraction of a flexible tube inside each module. Flexible Peltiers are placed between modules to absorb heat from one module and to deliver heat to the other module. One module expands when heated, and the other one expands when cooled. The research objectives of the proposal are to: (1) understand the underlying multi-physics (electro-thermo-mechanical) governing the operation of the actuator and the network, (2) create a framework for optimizing the network performance and establishing the effect of the actuator’s design parameters on the performance, (3) develop a versatile and robust control scheme, and (4) demonstrate the capabilities of the proposed networked actuators to be used as a drivetrain for a prosthetic elbow.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.