sentences:  The MGS, originally designed and produced by the Autonetics Division of North American Aviation, could store multiple preprogrammed targets in its internal memory.Unlike other methods of navigation, inertial guidance does not rely on observations of land positions or the stars, radio or radar signals, or any other information from outside the vehicle.Instead, the inertial navigator provides the guidance information using gyroscopes that indicate direction and accelerometers that measure changes in speed and direction.