Effect of Frequency in Vibration Stimulation for Human Elbow Extension Motion Change: A Fundamental Study for Upper-limb Perception Assist

Human motion can be changed from his/her intended motion by giving vibration stimulation to an antagonist muscle. One of the causes of this motion change is supposed to be the kinesthetic illusion which is induced by vibration stimulation. On the other hand, it is known that there is a relationship between the vividness of kinesthetic illusion and the frequency. When the frequency increases, the vividness of kinesthetic also increases. It indicates that the amount of human motion change induced by vibration stimulation can be controlled by frequency change. In this study, in order to evaluate the effect of frequency change to the amount of human elbow joint motion change, a psychophysical experiment was carried out with 4 healthy experimental participants. In this experiment, vibration stimulation was added to the tendon of biceps brachii during elbow joint extension motion. The frequency of vibration stimulation was 30, 60 and 90 (Hz) with each trial of the experiment. The experimental results show that the amount of elbow joint motion change increases when the frequency increases. These results indicate that the Perception-Assist with vibration stimulation can be carried out using frequency change.