Systems and methods for model based inertial navigation for a spinning projectile

A method embodiment for model based inertial navigation for a spinning projectile, the method comprising:

• inputting inertial sensor data from inertial sensors and inputting navigation corrections from a propagator-estimator filter to generate a navigation solution, the navigation solution comprising at least a projectile velocity estimate and an attitude estimate;
• executing a spinning projectile physics model configured to perform calculations utilizing dynamics equations for a rigid body, wherein the spinning projectile physics model inputs 1) one or more projectile state estimates from the navigation solution and 2) one or more platform input measurements indicative of forces acting on the projectile platform;
• calculating with the spinning projectile physics model a set of three orthogonal predicted translational acceleration measurements as a function of the one or more projectile state estimates and the platform input measurements;
• executing an upfinding navigation aid to generate an angular attitude measurement indicative of a roll angle of the spinning projectile with respect to the Earth;
• and
• calculating the navigation corrections as a function of the navigation solution and further utilizing as navigation aiding sources the set of predicted translational acceleration measurements from the spinning projectile physics model and the angular attitude measurement from the upfinding navigation aid, wherein the propagator-estimator filter comprises a measurement equation associated with the physics model and the upfinding navigation aid.