Motion Detection (FTC)

Detecting motion/no-motion can be simply detected by determining if a body’s linear acceleration exceeds a small threshold.

Using the data directly from accelerometers, this is not as easy as it seems, since raw accelerometer readings contain both acceleration due to gravity as well as acceleration due to a body’s motion. One method for detecting motion with raw acceleration data is to use a high-pass filter, which lets quickly-changing information through but blocks information that doesn’t change frequently.

However, a more comprehensive and reliable approach is to subtract the acceleration due to gravity from the raw acceleration values. The result value is known as “world linear acceleration”, representing the actual amount of acceleration due to motion, and is calculated automatically by navX-Micro’s motion processor.  Whenever the sum of the world linear acceleration in both the X and Y axes exceeds a “motion threshold”, motion is occurring.

FTC Android Example