title: A Wearable Hip Assist Robot Can Improve Gait Function and Cardiopulmonary Metabolic Efficiency in Elderly Adults.
abstract: The aims of this paper were to investigate the effectiveness of a newly developed wearable hip assist robot, that uses an active assist algorithm to improve gait function, muscle effort, and cardiopulmonary metabolic efficiency in elderly adults. Thirty elderly adults (15 males/ 15 females) participated in thispaper. The experimental protocol consisted of overground gait at comfortable speed under three different conditions: free gait without robot assistance, robot-assisted gait with zero torque (RAG-Z), and full RAG. Under all conditions, muscle effort was analyzed using a 12-channel surface electromyography system. Spatio-temporal data were collected at 120 Hz using a 3-D motion capture system with six infrared cameras. Metabolic cost parameters were collected as oxygen consumption per unit (ml/min/kg) and aerobic energy expenditure (Kcal/min). In the RAG condition, participants demonstrated improved gait function, decreased muscle effort, and reduced metabolic cost. Although the hip assist robot only provides assistance at the hip joint, our results demonstrated a clear reduction in knee and ankle muscle activity in addition to decreased hip flexor and extensor activity. Our findings suggest that this robot has the potential to improve stabilization of the trunk during walking in elderly adults.
authors.forename: Hwang-Jae
authors.initials: HJ
authors.lastname: Lee
authors.forename: Suhyun
authors.initials: S
authors.lastname: Lee
authors.forename: Won Hyuk
authors.initials: WH
authors.lastname: Chang
authors.forename: Keehong
authors.initials: K
authors.lastname: Seo
authors.forename: Youngbo
authors.initials: Y
authors.lastname: Shim
authors.forename: Byung-Ok
authors.initials: BO
authors.lastname: Choi
authors.forename: Gyu-Ha
authors.initials: GH
authors.lastname: Ryu
authors.forename: Yun-Hee
authors.initials: YH
authors.lastname: Kim
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004867:Equipment Design; D019544:Equipment Failure Analysis; D000067190:Exoskeleton Device; D005260:Female; D020233:Gait Disorders, Neurologic / Q000503:physiopathology* / Q000534:rehabilitation*; D006801:Humans; D007595:Joint Prosthesis; D008297:Male; D000066530:Neurological Rehabilitation / Q000295:instrumentation / Q000379:methods; D010101:Oxygen Consumption / Q000502:physiology*; D015203:Reproducibility of Results; D012371:Robotics / Q000295:instrumentation*; D012680:Sensitivity and Specificity; D016896:Treatment Outcome