Methods involve using a guided munition (e.g., a mortar round or a grenade) that utilizes deployable flow effectors, activatable flow effectors and/or active flow control devices to extend the range and enhance the precision of traditional unguided munitions without increasing the charge needed for launch. Sensors such as accelerometers, magnetometers, IR sensors, rate gyros, and motor controller sensors feed signals into a controller which then actuates or deploys the flow effectors/flow control devices to achieve the enhanced characteristics.

A guided munition system includes a munition body including at least one fluid dynamic control for changing course of the munition body in flight. A seeker onboard the munition body is operatively connected to control the at least one fluid dynamic control. The seeker includes a coded aperture imaging device facing outward from the munition body for image based control for guiding the munition body in flight.

The system and method for accurately determining range-to-go for the command detonation of a projectile. Using dual laser and/or radio frequency detectors on the tail and on the nose of a spinning projectile to determine the range-to-go, time-to-go, or lateral offset from the projectile to the target.

A guided munition system includes a munition body including at least one fluid dynamic control for changing course of the munition body in flight. A seeker onboard the munition body is operatively connected to control the at least one fluid dynamic control. The seeker includes a coded aperture imaging device facing outward from the munition body for image based control for guiding the munition body in flight.

The system and method for accurately determining range-to-go for the command detonation of a projectile. Using dual laser and/or radio frequency detectors on the tail and on the nose of a spinning projectile to determine the range-to-go, time-to-go, or lateral offset from the projectile to the target.

Techniques are provided for determination of a guided-munition orientation during flight based on lateral acceleration, velocity, and turn rate of the guided-munition. A methodology implementing the techniques, according to an embodiment, includes obtaining a lateral acceleration vector measurement and a velocity of the guided-munition, and calculating a ratio of the two, to generate an estimated lateral turn vector of the guided-munition. The method also includes integrating the estimated lateral turn vector, over a period of time associated with flight of the guided-munition, to generate a first type of predicted attitude change. The method further includes obtaining and integrating a lateral turn rate vector measurement of the guided-munition, over the period of time associated with flight of the guided-munition, to generate a second type of predicted attitude change. The method further includes calculating a gravity direction vector based on a difference between the first and second types of predicted attitude change.

A system for finding up in a projectile flight relative to earth. The system having a transmitter which transmits polarized reference signals to a guidance sub-system on the projectile. The guidance sub-system includes a magnetometer and polarized and non-polarized receivers. Measurements from the magnetometer are used to determine a general up direction. The polarized and non-polarized receivers are arranged such that, during rotation of the projectile, reference signals received by the polarized receiver modulate whereas reference signals received by the non-polarized receivers are unaffected. A ratio of the strengths of the signals received by the polarized and non-polarized receivers determines alignment of a vertical axis. From the general up direction and alignment of the vertical axis, a precise up direction of the projectile in flight relative to the earth can be determined.

Model based inertial navigation for a spinning projectile is provided. In one embodiment, a navigation system comprises: a strapdown navigation processor; a propagator-estimator filter, the processor inputs inertial sensor data and navigation corrections from the filter to generate a navigation solution comprising projectile velocity and attitude estimates; an upfinding navigation aid that generates an angular attitude measurement indicative of a roll angle; and a physics model performing calculations utilizing dynamics equations for a rigid body, the model inputs 1) projectile state estimates from the navigation solution and 2) platform inputs indicative of forces acting on a projectile platform, and outputs a set of three orthogonal predicted translational acceleration measurements based on the inputs; the filter comprises a measurement equation associated with the physics model and the upfinding navigation aid and calculates the navigation corrections as a function of the navigation solution, the predicted translational acceleration measurements, and attitude measurement.

Model based inertial navigation for a spinning projectile is provided. In one embodiment, a navigation system comprises: a strapdown navigation processor; a propagator-estimator filter, the processor inputs inertial sensor data and navigation corrections from the filter to generate a navigation solution comprising projectile velocity and attitude estimates; an upfinding navigation aid that generates an angular attitude measurement indicative of a roll angle; and a physics model performing calculations utilizing dynamics equations for a rigid body, the model inputs 1) projectile state estimates from the navigation solution and 2) platform inputs indicative of forces acting on a projectile platform, and outputs a set of three orthogonal predicted translational acceleration measurements based on the inputs; the filter comprises a measurement equation associated with the physics model and the upfinding navigation aid and calculates the navigation corrections as a function of the navigation solution, the predicted translational acceleration measurements, and attitude measurement.

Systems and methods for a tightly coupled trajectory predictor with constant up-finding are provided. In certain embodiments, a system includes an inertial measurement unit that provides inertial measurements of a vehicle. The system also includes an up-finding sensor that provides up-finding measurements based on when a portion of the vehicle is pointing up. Further, the system includes one or more processors that bound errors from the inertial measurements in a navigation solution during navigation of the vehicle using the up-finding measurements.