Rapid transfer alignment for tactical weapon applications

Abstract

Inertial Navigation Sysreni (INS) concepts offer attractive benefits when applied to modern air-to-gro~~nd weapons because of countermeasures invulnerability, rapidly reducing size and cost and the ability to reduce the performance demands of terminal g~~ida i ice s ekers. Traditional INS transfer alignment methods place both time and maneuver constraints on tactical l a~mch timelines which detract from INS ~ ~ t i l i t y in tactical scenarios. A rapid transfer alignment approach is presented uliich allows alignment in less than ten seconds to an accuracy of less than one nirad w i t h o ~ ~ t the req~iirement for aircraft lateral plane maneuvers. The alignment approach augments the traditional nlasterislave velocity concept with masterlslave a t t i t ~ ~ d e matching wliich allows alignment error observability with rotational maneuvers. The resulting 24-state, 6-measurement Kalman filter is shown to be implementable using commercially available microprocessors with achieved filter update rates of 36 Hz.