A Semi-Wearable Robotic Device for Sit-to-Stand Assistance.

With the aging of the population in the United States, an increasing number of individuals suffer from mobility challenges. For such individuals, the difficulty of standing up from a seated position is a major barrier for their daily physical activities. In the paper, a novel assistive device, namely Semi-Wearable Sit-to-Stand Assist (SW-SiStA), is presented, which provides effective lower-limb assistance to overcome such difficulty for the mobility-challenged individuals. Unlike traditional exoskeletons, the SW-SiStA can be easily detached after the completion of the sit-to-stand process, and thus will not cause additional burden to the user during the subsequent ambulation. The SW-SiStA is powered with a pneumatic actuator, leverage its advantages of low cost and high power/force density. The complexity of the device is reduced by the use of a simple solenoid valve in combination with two adjustable needle valves, providing the desired individualized adjustability without the expensive proportional valves. Human testing of the device indicated that the SW-SiStA was able to provide effective sit-to-stand assistance in a natural way, and the users were able to expend significantly less muscle efforts in the process.