The system and method of attitude determination by pulse beacon and extremely low cost inertial measuring unit. A pulse beacon is used to generate a plurality of pulses detected by a detector or receiver located on the rear of a projectile such that direction of arrival can be determined. A synchronized clock proved for velocity and range information. Altitude can also be determined and may use an altimeter or the like. The use of a low cost IMU is possible with internal calibration by the system. Real-time attitude information provides for correction for crosswind and other drift enabling the system to have less down range dispersion.

The system and method of attitude determination by pulse beacon and extremely low cost inertial measuring unit. A pulse beacon is used to generate a plurality of pulses detected by a detector or receiver located on the rear of a projectile such that direction of arrival can be determined. A synchronized clock proved for velocity and range information. Altitude can also be determined and may use an altimeter or the like. The use of a low cost IMU is possible with internal calibration by the system. Real-time attitude information provides for correction for crosswind and other drift enabling the system to have less down range dispersion.

Apparatus and associated methods relate to determining a course-correction signal for a spin-stabilized projectile based on a time sequence of images of a scene aligned with and obtained by a forward-looking imager coupled to the projectile. As the projectile rotates, the aligned scenes captured in the images obtained by the forward-looking imager are rotated. The rotation angle of each of the captured scenes corresponds to the spin angle of the projectile at the time of image exposure. Objects in the captured scenes will circle about a rotation center of the time-sequence images. The distances from a rotation center to the objects in the captured scenes, as well as the rotation angles of the captured scenes can be used to generate a course-correction signal so that the projectile can be guided to a target selected from the objects in the captured scene.

A method and system for nonlinear trajectory shaping guidance law capable of providing a robust guidance solution suitable for multi-mission, multi-mode operations. The nonlinear trajectory shaping guidance law offers (1) a dual layered GL gains calculation: (i) NTS time varying adjustment accounting for engine on/off and L/D variation and (ii) general explicit guidance algorithm based sub-optimal fixed-gain selection while still maintaining its trajectory shaping capability for short range to go missions; (2) flight path angle (FPA) command tracking and following to ensure a high probability of target destruction while minimizing collateral damages; (3) high precision impact point calculation factoring in target location errors or motion and maneuvering uncertainties.; and (4) heading error angle minimization.

An aircraft control device calculates trajectories of multiple aircraft that is member of a flight by use of a method such as Direct Collocation with Nonlinear Programming (DCNLP), in which an optimal solution is obtained by discretizing continuous variables. Nodes indicating the trajectory are calculated and set by substituting a discretized control variable of the aircraft into an aircraft equation of motion, or by use of other methods. Instead of calculating the trajectory of the aircraft as a continuous problem, discretisation reduces the calculation amount and time required for the trajectory calculation. The aircraft control device then determines, from among trajectories satisfying constraints corresponding to the role of the aircraft, an optimal trajectory based on an evaluation value obtained by an objective function corresponding to the role. Accordingly, the aircraft control device can calculate a more optimal trajectory corresponding to the role of the aircraft in a shorter time.

Systems are disclosed for navigating a missile to a target using a fixed sensor onboard the missile. In an embodiment, a system includes a launch platform traveling a pre-programmed route to deliver the missile within an area. The missile travels a first flight path through the area in effort to detect targets. If no targets are detected along the first flight path, the missile transitions to a second flight path, different from the first flight path, to locate targets off-axis relative to the first flight path. While the missile travels the second flight path, the sensor receives signal identifying a target located at a position off-axis relative to the first flight path. The missile then adjusts the second flight path to direct the missile to the target. In an example embodiment, the first flight path is straight or arced, while the second flight path is u-shaped, corkscrew-shaped, or spiral-shaped.

In a guiding device, a communication device receives a signal containing detection data of a target, and a processing unit. In the processing unit, a course setting section sets a flight course for a lofted flight based on the detection data, and a guiding section determines a progressing direction based on the flight course and outputs a guidance signal containing the progressing direction. The course setting section sets a first flight course when the flying object is launched. Also, the course setting section changes the first flight course to a second flight course based on the detection data after launching of the flying object.

A method and system for constraining navigational drift in a munition caused by Inertial Measurement Unit (IMU) bias error during flight of the munition in a constellation of a plurality of munitions in a Global Positioning System (GPS) denied attack. Each munition is provided with a datalink communication system to communicate with other munitions in the constellation and a navigation system having an IMU for guiding the munition in flight. An estimated position and covariance of the estimated position is determined for each munition via each munitions' navigation system. A range of each munition relative to at least one other munition in the munition constellation is determined via each munitions' datalink communication system. The estimated position and range to at least one other munition in the munition constellation is shared by each munition via each munitions' datalink communication system. Navigational drift for each munition is determined utilizing the estimated position of at least one other munition and the range to that at least one other munition in the munition constellation. And navigational drift in each munition is constrained by compensating for IMU bias error in each munition utilizing the determined navigational drift for each respective munition in the munition constellation.

A device, system, and method for shaping the trajectory of a projectile employing a Gravity bias, Gbias. The system includes a seeker, a guidance filter, a pitch rate filter, an actuator, pitch/yaw/roll coupled aerodynamics, and lateral rate sensors. It receives roll orientation input to a guidance and control autopilot; it applies Additional Gbias to that produced by the null rate command to the lateral control loops of the guidance and control autopilot device. The lateral rate command is equal to the desired Additional Gbias divided by an estimate of the projectile velocity. The Additional Gbias is translated to a rate command and incorporated into guidance loop commands to boost an Inherent Gbias to shape the trajectory of the projectile to the target.

According to an aspect of the invention, there is provided a control system for controlling a projectile, the control system comprising: a plurality of transmitters, wherein each transmitter of the plurality of transmitters is arranged to transmit an electromagnetic wave from a transmission position; a receiver associated with the projectile, the receiver being arranged to receive a plurality of electromagnetic waves transmitted from the plurality of transmitters; a controller associated with the projectile, the controller being arranged to: determine at least one of a position, a velocity or an acceleration of the projectile from transmission positions of the plurality of transmitters and Doppler measurements derived from the received plurality of electromagnetic waves; and generate a control signal for performing an action with the projectile depending on the determined at least one of position, velocity or acceleration of the projectile.