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The mechanization of a gimballess inertial system for space navigation is considered. An error analysis reveals that the errors contain both sinusoidal and diverging components. Error damping methods are proposed and it is shown that damping can be achieved by using appropriate damping circuits and auxiliary information obtained from devices such as stellar trackers, velocity-measuring optical Doppler, or radar Doppler. Computer-stored reference-trajectory information can also be used for error damping.

Inertial navigation systems usually use gyroscopes to sense angular motion and use accelerometers to sense linear acceleration. It is feasible, however, using only linear accelerometers as sensors, to determine both the angular velocity and the linear acceleration of a vehicle. This paper presents and compares five configurations of linear accelerometers which may be used to determine both the angular motion and the linear motion of a vehicle.

A general mechanization in vehicular coordinates of a Gimballess Inertial System for space navigation is considered. The system is both nonlinear and multiloop with coupling between the loops. Linearized system error equations for the position errors are obtained and they are found to be unstable. An error damping method is proposed and it is shown that damping can be achieved. The method utilizes appropriate damping circuits and auxiliary information obtained by means of a sun tracker.