Micro SCARA Robot for Miniature Parts Assembling

摘要

In this report, application of newly developed ultra-small servo actuators to a micro SCARA robot is presented. An ultra-small servo actuator consists of a miniature brushless DC motor, a reduction gear, and an optical encoder for monitoring the rotation of the motor. Two prototypes of different sizes were developed: one is 3mm in diameter and 10mm in length, and the other is 5mm in diameter and 18mm in length. Including the vertical positioning of the hand the robot has three degrees of freedom. First, the structure of the ultra-small servo actuator is shown and then the output characteristics of the 3mmdiameter and the 5mm diameter servo actuators are described, respectively. Next, the structure and control system of the micro SCARA robot, which has a 24.5mmlong arm, are described. Finally, flexible micro actuators, combined in parallel and acting a miniature handling system, are reported. They enable the gentle handling of small, fragile objects. The prototype of this micro SCARA robot enables the assembly of miniature objects in a small space. In the future, we expect this robot to find application as an inspection robot in narrow spaces, such as in small-diameter pipelines.