4-Direction Tilt

The 4-directional tilt sensor reports tilt if it is tilted by more than roughly 30°.  It reports this tilt with high/low signals it sends with its OUT1 and OUT2 pins.

Parts

(1) 4-Directional Tilt Sensor 28036 
(2) 220 Ω resistors
Jumper wires: blue, red, black 

Schematic

Wiring

Script

Tests

Tilt the sensor in 4 directions and see the four letters: A, B, C, and D.  Note, if the sensor is lying flat, it will display position C.

How It Works

Inside the sensor, there is a light, a ball, and two light sensors.  Imagine rotating the sensor like a steering wheel.  When A is up and C is down, the ball covers the light, so both sensors transmit 0 V.  If B is up, phototransistor 1 is covered and OUT1 is 0 V.  But, phototransistor 2 detects light, so OUT2 is 3.3 V.  In position C, the ball is in the far corner, so both phototransistors detect light and both OUT1 and OUT2 send 3.3 V.  In position D, the ball covers the other phototransistor, so OUT1 is 0 V and OUT2 is 3.3 V.