The HiTechnic Acceleration Tilt Sensor contains a three-axis accelerometer that measures acceleration in three axes, x, y and z. Acceleration is measured in the range of –2g to +2g with scaling of approximately 200 counts per g.
The Acceleration Sensor connects to an sensor port using a standard wire and uses the digital I2C communications protocol. The acceleration measurement for each axis is refreshed approximately 100 times per second.
The three axes of measurement are labeled x, y, and z as shown.
The HiTechnic Acceleration Tilt Sensor can also be used to measure tilt in three axes. This is possible because gravity is perceived as acceleration. When the sensor is stationary and in the normal horizontal position, the x and y-axis will be near zero, because they are horizontal, while the z-axis will be near 200, which represents one g. If you tilt the sensor then gravity will also be detected on the other axis and the value for the z axis will go down. Since gravity is distributed among the three component vectors, the tilt of the sensor can be determined.