Hole position and inclination sensor with 2 dimensional PSD, and its application to automatic shaft inserting

Shaft inserting is a frequent and important operation for automatic parts assembly. We have developed a sensor that can detect in real time the position of hole center and its inclination using a 2D position sensitive device (PSD). The sensor can detect the hole position by using the signals for the center of the light part. When the hole is inclined, a black ellipse image is focused on the PSD, the total current of one pair of PSD electrode differs from that of another pair. Therefore the sensor can detect the hole inclination by this current difference. We have developed an automatic shaft inserting system by applying the position and inclination sensor to a parallel joint robot with four freedom.