5th limb: development of augmented expression system using extra limb

Technology for augmenting expressions is actively researched in fields such as social media, entertainment, and arts. It is being established as a business. Dancing to videos that are programmed in advance is one example. This method effectively augments the expressions in dancing; however, it is difficult to improvise. Although it can be interactive, it requires large-scale devices such as motion captures or a large number of cameras. The purpose of this study is to develop a wearable device that augments expressions and evaluate the effectiveness of this device for augmentation of expressions. The shape of this device is identical to the tail of an animal. The shape of the device changes using information from the body of the wearer and acts as a "5th" limb. It then augments the expressions of the wearer. The required information for changing shape includes back muscle tension, gait, and angle of the arm. This information is collected through measurements and estimates of bioelectrical signals, sole pressure, and angles of the arms. The device estimates the emotions and behavior of the user. In the experiments, the device is attached to a performer. The values of the sensor and the motions of the device are measured. Hence, it is confirmed that the device moves when it detects the behavior of the performer. In other words, the device mirrors the behavior of the people who use the system. Therefore, this system augments the expression of performers. In conclusion, a wearable device for augmenting expressions is developed, and it is considered that this system can augment the expression of performers on stage.