Adaptive matched augmented proportional navigation

Abstract

Two new adaptive homing guidance laws are developed which are variants of Augmented Proportional Navigation (PRONAV). The first guidance law commands flight path angle rate and is referred to as adaptive matched augmented PRONAV (AMAAP). The second guidance law commands linear acceleration and is referred to as adaptive matched augmented linear PRONAV (AMALP). The major attributes of these guidance laws are (1) they are the solutions of a linear quadratic control problem, (2) they do not require an estimate of time-to-go (tgo), (3) they are matched to a nonlinear model of the target's motion, (4) they adapt in real time to provide optimal guidance over each small segment of the intercept trajectory, and (5) they optimally account for missile deceleration.

What is claimed is:  
     
       1. A guided missile system using Adaptive Matched Augmented Proportional Navigation, wherein a guidance law algorithm directs tactical weapons to intercept against targets; 
       using a family of linear models comprising a number of members, where each member closely approximates a nonlinear kinematics model over a specific small segment of a trajectory, means providing solutions for a family of linear-quadratic optimal control problems which represents a family of guidance laws, wherein each member of this guidance law family represents an optimal guidance strategy over the corresponding small segment of the trajectory, so that the guidance laws are matched to a nonlinear kinematics model, and means in which an appropriate guidance law for each portion of the trajectory is then adaptively selected based on the estimates from a target state filter.  
       whereby the guidance law is an optimal guidance law in that it is a solution of a family of linear-quadratic regulator control problems and minimizes deviations from establishment of a collision course over the entire period of homing flights thereby indirectly minimizing miss distance.  
     
     
       2. The guided missile system using Adaptive Matched Augmented Proportional Navigation according to claim  1  wherein the guidance law algorithm includes means for commanding flight path angle rate. 
     
     
       3. The guided missile system using Adaptive Matched Augmented Proportional Navigation according to claim  1  wherein the guidance law algorithm includes means for commanding linear acceleration.