Over 20 million people in China are with hearing disabilities, and sign language is their major way of communicating. However, communicating with them in daily life is difficult since few people understand sign language. To solve the problem, Beijing Union University established a special group called "Union One" robot team to develop a robot which can speak in sign language. The robot is 140 centimeters tall, with hydraulic devices controlled by customized algorithms, which moves the joints, so that the robot can make signs and communicate with people.