A real-time interactive biofeedback system for sports training and rehabilitation

Biofeedback systems have become a prominent component in the sports domain as a means of motor training and rehabilitation. This paper presents the development of a biofeedback prototype and system software framework facilitating its functionality in real time. The prototype incorporates an inertial measurement sensor unit, a wireless vibration stimulus module for vibrotactile biofeedback, and interactive system software behaving as the backbone of the system. The functionality of the prototype was tested with a stability test during which biofeedback was provided to improve postural control based on trunk tilt displacements. The test involved subjects standing in the tandem Romberg position during which their medial lateral trunk tilt was measured, and postural sway biofeedback was conveyed via vibrotactile actuators placed on either side of the trunk. Two conditions were tested, namely eyes open and eyes closed, and postural sway with biofeedback was evaluated, as opposed to with no feedback. A 15.2 per cent sway reduction resulted in the eyes-open condition, and a significant reduction of 55.2 per cent was reported for the eyes-closed condition. The results demonstrate that instantaneous feedback provided via vibration stimulus can reduce postural sway based on trunk tilt measurements. Hence, the system's pertinence to comparable approaches employed in sports training and rehabilitation is foreseen.