Accelerometers

An accelerometer is a measuring device, and is used to measure the acceleration it experiences relative to freefall. Multi-axis and single axis models are available which can also allow the sensing of orientation. Accelerometers are used in video game controllers and portable electronic devices. An accelerometer measures the acceleration it experiences relative to freefall. This means inertial acceleration minus local gravitation acceleration. Inertial acceleration is the sense of acceleration to a fixed time frame, of which the Earth is said to be approximate.