GP1S036HEZ Tilt Sensor
This mini tilt sensor has 2 outputs to indicate one of four directions (up, down, right or left). Can also be used to indicate when your robot upside down or it can be used also as a barrier switch to detect the tilt angle.
Transmissive with photo-transistor output
Built-in a ball (2 phase output)
Compact PWB mounting type
Lead free and RoHS directive compliant