abstract
- Sit-to-stand (STS) performance is a key indicator of functional mobility and independence in aging populations, yet most assistive solutions remain limited by high cost, bulky designs, powered actuation, or dependence on laboratory-grade evaluation systems. This paper presents a low-cost passive wearable device based on a lateral spring mechanism designed to support knee extension during STS while aiming to minimize potential interference with daily mobility. A proof-of-concept evaluation was conducted using the Five-Times Sit-to-Stand (5TSTS) protocol under two conditions (with and without the device). Kinematic variables (knee angle and hip speed) were extracted from standard video recordings using Kinovea as an accessible motion analysis tool. Results showed reduced 5TSTS completion time for both participants when using the prototype, along with condition-dependent differences in knee angle range and hip speed profiles across cycles. The main contributions of this study include: (a) the development of a mechanically simple and low-cost passive wearable device for sit-to-stand (STS) assistance; (b) the establishment of a reproducible evaluation workflow utilizing the Five Times Sit-to-Stand Test (5TSTS) and video-based kinematic analysis; and (c) preliminary feasibility data indicating that the prototype may affect functional performance and movement dynamics across repeated STS cycles. However, these results should not be considered evidence of efficacy, given the proof-of-concept design and the limited sample size.