Vehicle guidance system

DETAILED DESCRIPTION With this background of the invention in mind it is an object of this invention to provide, for use in a vehicle guidance system wherein a vehicle is adapted to respond selectively to guidance signals derived from tracking data generated at a remote station and to tracking data generated by means contained within such vehicle, improved apparatus contained within the vehicle, such apparatus being adapted to provide both a reference element with a known angular orientation at the remote station and a gimballed tracking element.
It is another object of the invention to control the attitude of the above mentioned reference element without the use of three relatively costly and heavy mechanical servos.
These and other objects of the invention are attained generally by adapting the gimballed tracking element contained within a vehicle to function additionally as an attitude reference element, such element being stabilized by mechanical servo drives in pitch and yaw and stabilized by aerodynamical means in roll.
In a preferred embodiment, a gimballed target tracking antenna on a missile having two degrees of freedom with respect to the vehicle's body has mounted thereon, in addition to its conventional pair of rate sensing gyros, a third rate sensing gyro.
The three gyros are disposed to sense any angular change in the inertial orientation of the antenna.
The output signals from each one of the conventional pair of rate sensing gyros are used as input signals for one of the mechanical servo drives coupled to the antenna.
The output signals from the third rate sensing gyro are used as input signals to the missile's roll autopilot.
The two servo drives and the roll autopilot thus function to attitude stabilize the antenna, such attitude stabilized antenna thus being adapted to serve as a reference element for enabling proper transformation of guidance signals transmitted between the missile and a remote station during at least a portion of the missle 'flight and as a target tracking antenna