20140076087 | MOTOR SYSTEM, MOTOR, AND ROBOT ARM DEVICE COMPRISING THE SAME - The present invention is related to a motor system, a motor, and to a robot arm device comprising the same. According to the invention, a motor is provided comprising a rack having a periodic surface thereon which is engaged by a plurality of engaging elements. By driving the engaging elements back and forth towards the surface structure in a periodic and time shifted manner, a linear motion can be brought about. | 03-20-2014 |