Phase 2 case study~Two subjects will be fitted with a heart rate monitor and with an adapted waist belt with mobile phone attached.~RPL alignment will be verified.~The subjects will use the RPL in parallel bars 10 times and take rests as needed in a chair.~The subjects will perform the timed up and go test (TUGT), 10-meter walk test (10MWT), and the 6-minute walk test (6MWT).~The subjects will be fitted with retro-reflective markers.~The subjects will be fitted with a portable oxygen uptake analyzer.~A 4D motion-capture camera system will be used while performing TUGT and five times sit to stand (5XSTS).~The subjects will perform the above tests in their prescribed daily-wear prosthesis, and then in the RPL.~The subjects will complete the activities-based balance confidence (ABC) scale test.~The subjects will be asked a series of open-ended questions regarding the experience, while being audio recorded.~Phase 3 pilot study~Twenty subjects will be randomized into three treatment arms (no prosthesis, prescribed prosthesis, RPL).~The subject will be fitted with a heart rate monitor.~The subject will be fitted with a portable oxygen uptake analyzer.~The subject will be fitted with the RPL, and the alignment of the RPL will be confirmed before testing.~The subject will be fitted with retro-reflective markers.~A 4D motion-capture camera system and force-plate will be used while performing the 5XSTS test in the assigned randomized condition. The test will be performed three times in each condition.~The subject will return two more times to complete the tests in the remaining randomized conditions, with a two-week washout period between sessions.~The subject will be given the ABC scale test in the beginning and at the end of this study.~The subject will complete the technology attitudes questionnaire (TAQ).~In total, subject participation will last 1 hour per day, for three sessions, two weeks apart.
The purpose of this graduate student research study is to test that a specifically designed and novel robotic prosthetic leg (RPL) is feasible, safe and improves symmetry, efficiency, and metabolic function during sit-to-stand and stand-to-sit transitions as compared to the subject's prescribed device, and as compared to no device at all.