Inertial guidance is the name given to those types of systems which guide and keep track of the location of vehicles which are free to move in three dimensions. Vehicles which move only on a plane surface, such as ships or automobiles, require only an accurate compass, sextant, and clock to keep track of their present position. When a vehicle can travel up or down as well as north or east, it is much more difficult to fix its position. An inertial platform is used in inertial guidance to measure vehicle altitude and acceleration which are then integrated to provide position and velocity. The inertial platform consists of three gyroscopes and three accelerometers mounted in the inner gimbal of the four gimbal platform. The purpose of the inertial platform is to allow the vehicle to move in any direction about the inner gimbal containing the gyros and accelerometers, without disturbing or turning them from their original orientation. Thus the gyros and accelerometers do not mm when
A. to provide training information to new pilots and navigators.
B. to motivate people's interest in space travel.
C. to explain how to use an inertial guidance system.
D. to describe the structure and importance of an inertial guidance system.