A smart cushion system with vibrotactile feedback for active posture correction

Abstract

The developed system provides vibrotactile feedback through a pressure sensory cushion designed to be attachable to a chair in order to encourage users to sit upright. The sensory component of the cushion utilizes an array of 9 low-cost pressure sensors that detect the user’s presence and posture. The sensory cushion calibrates to the user’s upright posture using a guided setup implemented in a paired smart phone application. When the system detects inappropriate sitting posture such as slouching, vibrotactile feedback is delivered to the user as negative reinforcement. The vibration location is relative to the area in need of immediate posture correction. We conducted an experiment to observe the response of the user’s sitting posture to vibrotactile feedback. The experiments demonstrated a classification accuracy of 94.1% during calibration and showed that vibrotactile feedback was effective in encouraging users to sit upright with an increase of 56.7% of time spent seated upright.