Controller synthesis and clinical exploration of wearable gyroscopic actuators to support human balance

Abstract

Gyroscopic actuators are appealing for wearable applications due to their ability to provide overground balance support without obstructing the legs. Multiple wearable robots using this actuation principle have been proposed, but none has yet been evaluated with humans. Here we use the GyBAR, a backpack-like prototype portable robot, to investigate the hypothesis that the balance of both healthy and chronic stroke subjects can be augmented through moments applied to the upper body. We quantified balance performance in terms of each participant's ability to walk or remain standing on a narrow support surface oriented to challenge stability in either the frontal or the sagittal plane. By comparing candidate balance controllers, it was found that effective assistance did not require regulation to a reference posture. A rotational viscous field increased the distance healthy participants could walk along a 30mm-wide beam by a factor of 2.0, compared to when the GyBAR was worn but inactive. The same controller enabled individuals with chronic stroke to remain standing for a factor of 2.5 longer on a narrow block. Due to its wearability and versatility of control, the GyBAR could enable new therapy interventions for training and rehabilitation.

Feasibility Analysis of a Self-Reinforcing Electroadhesive Rotational Clutch

“…We investigate a possible application of the proposed clutch design a wearable balance assistance device, as previously described in [14], [15]. This device contains gyroscopic actuators in a backpack-like construction.…”

“…Therefore, we optimize the geometry to find the least sensitive configuration. We also present a design example based on the theoretical requirements for a gyroscopic balance assistance device [14], [15], [18]. In Section III, the estimated performance of an electroadhesive clutch based on the proposed design is compared to SEPAC RFTC-320 electromagnetic clutches, which currently deliver industryleading torque-to-mass and torque-to-power ratios [10], [24].…”

Improving Standing Balance Performance through the Assistance of a Mobile Collaborative Robot

“…A wearable backpack-like system capable of exerting recovery forces based on an actuated gimbal mechanism and a flywheel was proposed in [13]. The prototype was later tested on humans with promising results [14]. Nevertheless, the main limitation of this prototype is its low maximum payload, which may make it impractical for long-term use.…”

Moving on: measuring movement remotely after stroke

“…Contrarily, intuitive feedback can be provided by providing opposing forces or torques that correct the movement of the user. There are solutions such as the GyroGlove™ that helps reduce hand tremors (Panisse et al, 2016), or the GyBAR that helps with balance issues (Lemus et al, 2020).…”

“…The GyBAR is a gyroscope installed into a backpack (Lemus et al, 2020), and has been shown to improve the user's ability to walk further on a thin beam, and also standing balance for persons with stroke.…”