Development of Automatic Controlled Walking Assistive Device Based on Fatigue and Emotion Detection

The world’s aging population is increasing. The num-ber of elderly individuals having walking impairments is also increasing. Adequate exercise is becoming nec-essary for them. Therefore, several walking assistive devices have been developed or are under develop-ment. However, elderly individuals may have low motivation for exercising, or they may experience physical damage by excessive fatigue. This study proposed a method to enable elderly individuals to exercise with a positive emotion and prevent damage such as muscle fatigue. We proposed a 3D human condition model to control the walking assistive device. It includes the arousal, pleasure, and fatigue dimensions. With regard to the arousal and pleasure dimensions, we used heartbeat and electromyography (EEG) signals to train a deep neural network (DNN) model to iden-tify human emotions. For fatigue detection, we proposed a method based on near-infrared spectroscopy (NIRS) to detect muscle fatigue. All the sensors are portable. This implies that it can be used for outdoor activities. Then, we proposed a walking strategy based on a 3D human condition model to control the walking assistive device. Finally, we tested the effective-ness of the automatic control system. The wearing of the walking assistive device and implementation of the walking strategy can delay the fatigue time by approx-imately 24% and increase the walking distance by ap-proximately 16%. In addition, we succeeded in visu-alizing the distribution of emotion during each walking method variation. It was verified that the walking strategy can improve the mental condition of a user to a certain extent. These results showed the effective-ness of the proposed system. It could help elderlies maintain higher levels of motivation and prevent muscle damage by walking exercise, using the walking as-sistive device.