Missile

About: Missile is a research topic. Over the lifetime, 12829 publications have been published within this topic receiving 94307 citations. The topic is also known as: guided missile & missiles.

Combined Optimal/Classical Approach to Robust Missile Autopilot Design

Abstract: The direct application of optimal control techniques to a complete autopilot design leads to a control system which requires excessive instrumentation and is sensitive to variations in the high frequency model A better approach is presented which utilizes classical control theory to bound the high frequency design and modern control theory to obtain optimal low frequency performance Results are presented for a separation roll autopilot demonstrating the appropriate tradeoffs and benefits associated w i t h the new design procedure Air launched missiles require active autopilot control for safe separation from modern launch aircraft because the f low field in the vicinity of the aircraft causes large torque disturbances on the missile and because the aircraft may be m=euvering when it releases its missile The effect of these disturbances and initial conditions are typically sensed by rate gyros and accelerometers whose out puts are connected through autopilot control circuitry to f in actuators Initially autopilot design is carried out b 1 decoupling the pitch, yaw and roll channels ( When this is done,classicd control theory has proven itself to be a valuable and efficient tool for autopilot design However aerodynamic crosscouplin g exists because the surface features of the missile create asymmetric flow fields over the control surfaces at c??fferent orientations of wind angle and angle of attack A simplified block diagram showing the cross-coupling appears in Fig I Here, if the roll rate response time is close enough to the pitchfyaw response time and the cross-coupling aerodynamic gain is high enough, instability can result Therefore successful autopilot design must take into consideration aerodynamic cross-couph g Althou h classical design techniques are well established fi 9 345) and relatively straight forward for planar autopilot design, trial and error must b? A I ROLL AUTOPILOT 1 ACTUATOR AND a L SENSOR -

Directed infrared countermeasures (DIRCM) system and method

Abstract: An agile, high-power, reliable DIRCM system that is easily extended to address sophisticated UV or UV-visible capable multi-band threats includes a missile warner having missile warning receivers (MWRs), one or two-color suitably in the mid-IR range, that detect likely missile launch and pass the threat coordinates to a pointer-tracker having a Roll/Nod gimbal on which the IR laser transmitter is mounted. The pointer-tracker slews the gimbal to initiate tracking based on the threat coordinates and then uses its detector to continue to track and verify the threat. If the threat is verified, the pointer-tracker engages the laser to fire and jam the missile's IR seeker. By slewing the gimbal based on unverified threat coordinates to initiate tracking the system is highly agile and can respond to short and near simultaneous MANPADS shots.

Missile Acceleration in Proportional Navigation

Abstract: In a previous paper, the author obtained conditions for the acceleration of a missile pursuing a maneuvering target according to proportional navigation, to be bounded. This correspondence extends previous work, and new boundaries are obtained for the missile acceleration.

On validating simulation models of missile systems

Abstract: Simulation of missile systems is mainly used to pre dict missile flight and terminal miss distance and to study flight safety. Computer simulations of mis sile systems produce results that otherwise could only be obtained by actual tests and missile flights. The increasing cost of firings limits their number and hence reduces the amount of available flight-test data. Theil's inequality coefficients (TIC) and their geometric representations are the basis for a procedure which provides insight into the validity of a simulation and reduces the dependence of validation on flight-test data.

Missile guidance algorithm against high-g barrel roll maneuvers

Abstract: The features of high-# barrel rolls for an aircraft and the countermeasures for a proportional navigation guidance missile against this maneuver are studied First, the features of the barrell roll maneuver, and the effects of the parameters on the miss distance are discussed The simulation results show that a high-£ barrel roll maneuver generally produces a larger miss distance than a split-S (a sustained maximum g turn) and the miss distance does not critically depend on the maneuver initiation time, if the aircraft has a certain length of "time-to-go" and maneuvers with an appropriate roll rate Second, the inference is made that the provision of a phase lead in the pitch-yaw plane in the missile guidance loop and adoption of the augmented proportional navigation guidance may be effective It is also proven that a large phase shift (but less than ir/2) results in a smaller miss distance and that the combination of the phase lead and the augmented proportional navigation produces better results