Abstract
Physical disability presents challenges beyond a loss of function. Many patients who suffer injuries like stroke or amputation also face expensive treatments, substandard care, and a loss of financial and daily independence. It is important to consider the adaptive challenges a patient must face in their new routine when designing or seeking to understand a technical solution or treatment. Functional rehabilitation is a philosophy which prioritizes incrementally rebuilding pre-injury abilities towards the ultimate end of empowering a patient to regain their full independence. The goals of any functional regimen are defined collaboratively between provider and patient, so that the methods and treatments can be tailored to their needs. Customizability is a key component of functional rehabilitation. However, to significantly impact a given disabled community, the rehabilitation program must also be scalable and affordable. Thus, while functional rehabilitation is effective in rebuilding the abilities, mental health, and dignity of a patient, providers must optimize the tradeoffs between flexibility and scaled economy. The following two projects are attempts to find this optimal balance, one through design and another through a sociotechnical analysis of the development of prosthetic technologies.
Around 800,000 Americans per year suffer a stroke. Amongst them, one of the most common results is a loss of strength or mobility on one side of the body, called hemiparesis. To regain functionality, the affected muscle groups must undergo repeated assisted motion to rebuild the mind-muscle connection. Typically, this is performed at a clinic by physical therapists, which can be costly and inconvenient. We sought to bring stroke rehabilitation into the living rooms of patients by designing a wearable, customizable, soft robotic, four degree-of-freedom lower arm exoskeleton. Many existing robotic rehabilitation solutions are hard systems, meaning they are composed of rigid metal segments. For safety, affordability, and comfort we used only flexible components to target all types of lower-arm motion. With a motor-and-cable system, the team actuated the elbow and rotated the wrist. Using two parallel linear actuators and flexible adapters, the wrist was made to extend and abduct. The final product was capable of fitting all group members, who represented roughly the 20% female to 80% male range. The design achieved the fully desired range of motion in two of the four degrees of freedom, and supported at least half of the user’s arm weight to assist motion in every degree of freedom. We concluded that soft robotic cable and linear actuator systems were feasible and affordable, and recommended that further research be done to incorporate the sensing of user intent to trigger motion.
For many physical disabilities, the stigma of their condition is one of the greatest hurdles to a patient’s reintegration into society. This is true of many people today, but was exemplified by the ostracisation of disabled veterans in the 19th century following the American Civil War. By the end of World War One, however, this stigma had evaporated and the quality of care for amputees had dramatically improved. To explore this correlation, I investigated what the state of technology was in both time frames, what influences impacted public sentiments, and explored other possible explanations for the advancement. I discovered that at the outbreak of conflict in both cases all veterans were glorified. However, the public lost its sympathy as the Civil War took its economic and social toll and, even after the cessation of hostilities, the pensions of veterans grew to be the largest expense of the federal budget. This was not the case in World War One, as the United States were only involved for part of the conflict and the state media apparatus became powerful enough to maintain veterans’ heroic status. In the network of actors influencing prosthetic technology, the investment of the government into functional rehabilitation – in part to eventually get veterans off of welfare – stimulated the entire technological ecosystem to innovate and improve care. While the elimination of stigma is necessary to provide better treatments, it is not sufficient, and advancements usually require economic opportunity and considerable investment.
Notes
School of Engineering and Applied Science
Bachelor of Science in Mechanical Engineering
Technical Advisor: Sarah Sun
STS Advisor: Kent Wayland
Technical Team Members: Aidan Mermagen, Andrew Wittman, Hannah Tse, Juan Gomez, Katherine Page, Madelyn Tubbs, Ryan Murray, Sean Pawlowski, Zoe Benton
