Design and Usability Evaluation of a Tremor-Stabilizing Spoon System for Individuals with Hand Tremor

Abstract

A tremor-stabilizing spoon system can support independent eating in older adults and individuals with upper-limb tremor by reducing unwanted motion during food transfer. The proposed system uses a 2-DOF stabilization mechanism that targets roll and pitch axis motion of the spoon. Tremor-related angular motion is detected using an IMU sensor, and the estimated roll and pitch errors are compensated by DC motor actuation to reduce vibration at the spoon head. To improve the practicality of the sys tem as an assistive device, the electronic circuits and components required for system operation were integrated into a single printed circuit board, while the housing was fabricated using 3D printing to enhance accessibility and ease of modification. System performance was first validated using bench test under controlled vibration conditions. The results confirmed the basic tremor reduction capability of the proposed system. Roll-axis stabilization was achieved from 1 to 4 Hz, with a maximum vibration re duction of approximately 70%. Pitch-axis stabilization was achieved from 1 to 3 Hz, with a maximum vibration reduction of approximately 40%. These results indicate that the prototype can provide measurable vibration attenuation within the low-frequency tremor range under controlled experimental conditions. A user evaluation was also con ducted with two participants with hand tremor. Task performance, subjective work load, satisfaction, and user feedback were evaluated under Ordinary spoon, System OFF, and System ON conditions. The proposed prototype demonstrates the feasibil ity of a low-cost 2-DOF tremor-stabilizing spoon and provides an initial validation– i framework combining quantitative bench test and user evaluation