Robot arm has a wide range of applications in industry, which can assemble Iron Man, cars, etc., but it seems very far away from our lives. Because of its huge volume, high price and the difficulty of operation, so that we stay away from it. But it’s so charming that it has been attracting players to develop a variety of desktop robot arm, making it moved to our desktop. However, the current desktop is mainly steering structure. Precision above 10mm cannot meet in the exploration of robot arm applications, only as a toy.