Showing papers on "Missile published in 1985"

The evolution of the cruise missile

Abstract: : While weapons come and go in the military, history provides examples of classes of weapons having both a dramatic and a lasting impact upon the conduct of warfare. These examples involve weapons which were, at their inception, revolutionary since they were not merely new but clearly superior to equipment already in use on the battlefield. Because they dominated warfare they were crucial to battlefield success; and nations possessing and using such weapons effectively were, more often than not, victorious. A class of missile of particular interest, now entering the US inventory, is the cruise missile. The purpose of this study is to evaluate the cruise missile against the criteria suggested above, seeking answers to two basic questions: Is the current cruise missile simply another weapon in the now familiar class of aerial munitions? Or does it represent a potentially revolutionary class of weapons in its own right? These questions, and the answers to them, may well have far-reaching implications, for if the current version of the cruise missile represents not an evolutionary development but a quantum leap forward in weaponry, then US development and employment strategies require significant adjustment.

Maximum-information guidance for homing missiles

Abstract: A recently-defined information index is used to enhance the information content of minimum-control-effort trajectories for the homing missile intercept problem. Optimal planar intercept trajectories are obtained for a performance index which is control effort weighted by position information content. The missile and target are assumed to be operating at constant speed. The shooting method is used to compute the optimal paths; but because of the simplicity of the model, on-line optimization yielding a guidance law with information enhancement should be possible.

Multi-warhead, anti-armor missile

Abstract: A multi-warhead, anti-armor missile which includes a missile that has a bter section, a sustainer section, guidance and control means, and primary and secondary warhead sections at nose portions of the missile, with said primary warhead being designed for defeating basic armor of an enemy target and said secondary warheads being designed for dispersal into a cluster prior to the missile arriving at the target and arranged for defeating advanced armor explosive positioned around the basic armor.

Target acquisition system

Abstract: A target acquisition system for a mobile air defense system is capable of acquiring and engaging targets in rapid sequence while mounted on a moving vehicle. It incorporates a gyrostabilized turret drive system, an optical sight, a forward looking infrared scanner, an infared guided missile subsystem, an onboard computer, and system controls and displays. The turret drive will maintain a particular elevation and azimuth regardless of the motion of the vehicle on which the turret is mounted so that the target tracking system need not account for movement of the vehicle over the ground. The optical sight projects a set of reticles on a combining glass in front of the gunner, which shows the target on which the missile seeker is locked as well as the target at which the turret is pointed so that gunner can insure that the missile is locked on the correct target. Critical systems status signals are also displayed on the sight reticle by use of symbology so the gunner can monitor the key systems without taking his eyes off the target. The missile system controls eight missiles, two being activated at any one time, and notifies the gunner by an audio tone that the missile is locked onto a target and is ready to fire. The missile firing sequence is automatically controlled by the control electronics and inserts super elevation and lead angle automatically, and selects and activates the next missile to be fired without delay.

Fiber optic track/reaim system

Abstract: In a missile tracking and guidance system, a fiber optic link is maintained between a missile and the launcher. Tracking after launch is via a video link between the missile seeker and a video imager at the launcher. Guidance signals are derived from the video signal input to the imager and transmitted back to the missile. Additionally, rate sensors and an interrupt or reaim circuit within the launcher allows an operator to reacquire the target for refining the missile seeker look axis toward a target during flight. After the target aimpoint is refined the operator can then release the interrupt circuit, allowing the system to continue tracking from the video input, with a newly established seeker heading established during the aimpoint refinement.

Estimation of the time-to-go parameter for air-to-air missiles

Abstract: The design of optimal controllers for air-to-air missiles has been of much recent interest. Many control laws require a good estimate of the time-to-go (tgo) before intercept. This paper presents an algorithm for estimating time-to-go using the current relative position and velocity characteristics of the missile and target. By constructing an objective function representing teminal miss distance, one is able to obtain an iterative scheme for estimating tgo. Simulation studies using a smart target algorithm and this methodology have yielded good results that show improvement over conventional algorithms for estimating tgo. A comparative investigation of the methodology developed in this paper with other algorithms is presented.

A missile duel between two aircraft

Abstract: A delicate differential game is formed by two aircraft performing a long-range missile duel. The duel starts for each aircraft with a semiagressive phase until the launch of the missile, when a pure evasion commences. In numerically solving the nonlinear differential game problem, an optimization algorithm is used consisting of a modified first-order differential dynamic programming method combined with an effective convergence-control technique. The three-dimensional spatial motion of point mass vehicles with realistic models is treated. The results of optimizing the problem point out the potential of new tactics. If the vehicles are free to maneuver in altitude, the contributions from the missiles will dominate the outcome of the game. Of particular importance is the desirable ability to enter the game at a higher altitude than that of the opponent.

Electronic image stabilization

Abstract: In an optical guidance system, body fixed electronic image stabilization of television imaging is used to allow strapdown seeker guidance in a missile. Electronic image stabilization eliminates the need for a stabilized sensor or seeker platform while providing the same line-of-sight information that would have been obtained from the platform. Body fixed electronic image stabilization compensates for routine vibrational and rotational motion experienced by a missile airframe during flight. This compensation is accomplished by deliberately underscanning the camera and driving the camera's deflection coils with signals from pitch and yaw body rate sensors on the missile. The image developed on the camera detector raster is thereby moved in an equal and opposite direction to the sensed, experienced, motion during the same instant that the motion is occuring. Compensation thus stabilizes the resultant image, which would otherwise be a blur of motion on the display screen.

A new guidance law for homing missiles

Abstract: this paper presents a new type of guidance law for homing missiles. The design concept is based upon the minimization of time duration for homing. It is shown that to realize this guidance concept an algorithm to predict the collision course and a guidance command generator to turn the heading of the missile toward the direction of the predicted collision course are necessary. A prediction algorithm for the collision course is derived and the realized overall guidance law is shown to be easily implementable. Simulation results are given to demonstrate the minimum time behavior and the widened launching envelope.

Extension of equivalent angle-of-attack method for nonlinear flowfields

Abstract: Recent experimental results show that the control effectiveness of a missile fin in supersonic flow at moderate to high angles of attack is a strong nonlinear function of freestream Mach number, body incidence angle, fin bank angle, and fin deflection angle. Analysis of the experimental results using an Euler finite-difference computer code with flow separation, together with the equivalent angle-of-attack concept, indicates that the observed nonlinearities are due to the variation of local dynamic pressure and local Mach number around the missile body alone. The nonlinearities are shown to be a strong source of control cross-coupling for high Mach number, high angle-ofattack combinations. The analysis suggests a relatively simple yet comprehensive approach for accurately accounting for these nonlinear effects. The impact of the results on missile aeroprediction methods is discussed.

Guidance performance analysis with in-flight radome error calibration

Abstract: ^Cornford, B.A. and Bain, M.A., "The Kinematics of Proportional Navigation Courses for a Missile with a Time Lag," Royal Aircraft Establishment, England, Tech. Note GW85, Oct. 1950. Paarman, L.O., Farone, J.M., and Smoots, G.W., "Guidance Law Handback for Classical Proportional Navigation," IIT Research Institute, Chicago, 111, Rept. GACIAC HB-78-01, June 1978. Pastrick, H.L., Seltzer, S.M., and Warren, M.E., "Guidance Laws for Snort-Range Tactical Missiles," Journal of Guidance and Control, March-April 1981, pp. 98-108. 1 ^Arbenz, K., "Proportional Navigation of Nonstationary Targets," IEEE Transactions on Aerospace and Electronic Systems, July 1970, pp. 455-457. , Nesline, F.W. and Zarchan, P., "A New Look at Classical ys Modern Homing Missile Guidance," Journal of Guidance and Control, Jani-Feb. 1981, pp. 78-85. Smith, W.M., "Preliminary Trajectory Shaping Policy for SM2 Block 11 ER/HAW," General Dynamics, Pomona, Calif., TM 6-331-119.30.1, Jan. 1979. Chadwiek, W.R., "A Theoretical Analysis of Collision Course Navigation with Command Guidance," Weapons Research Establishment, South Australia, 1%ch. Note SAD 141, Dec. 1964.

Impact and perforation of cylindrical shells by blunt missiles

Abstract: Experiments on perforation of thin-walled, mild steel tubes by non-deforming spherical missiles that impact at normal obliquity are compared with previous studies of thin-plate perforation. In these experiments, the missile radius R m is larger than the tube wall thickness h but substantially smaller than the tube radius R t . For both plates and shells, impact by blunt-nosed missiles results in two simple modes of deformation near the impact point - plugging and dishing. Spherical missiles penetrating thin shells primarily dish the surface; the initial fracture leading to perforation is caused by tensile radial stress around the contact region. This brittle fracture propagates from the distal surface through part of the thickness before linking with a ductile fracture that completes the plug formation process. The brittle fracture is first apparent on the distal surface at a substantially smaller impact velocity than is required for perforation of the tube wall. Following plug formation, the hole enlargement proceeds by petalling or plastic expansion until the missile passes through the tube wall. Both fracture and the ballistic limit of steel tubes are related to the relative size of the spherical missile and its kinetic energy at impact.

Missile system and method for performing automatic fire control

Abstract: A missile system and method for performing automatic fire control in which a reconnaissance vehicle is used to gather video reference information of a target and this information is then communicated to a launching vehicle from which missiles are caused to be trained on the selected target by utilizing an automatic target handoff correlator that identifies the selected target, causes an autotracker to be locked on and finally a computer is signaled by the automatic target handoff correlator to cause a missile to be fired.

Optimal controller for homing missile

Abstract: The optimal control theory is applied to the homing missile lateral autopilot design. The approach is to adapt the autopilot gains to the environment model reference and to vary as functions of time-to-go to minimize the performance index. The path constraint is applied throughout the whole terminal homing period and infinite penalty is imposed at intercept. A single-plane, linear autopilot design and implementation consideration are addressed for skid-to-turn (STT) case. Application to bank-to-turn (BTT) control is also discussed.

Laser device for guiding a missile on a target

Abstract: A laser device for guiding a missile to a target such as an enemy tank, includes a laser transmitter (1) which transmits radiation (2) which is received by a modulator (30) capable of delivering two distinct pulsed beams (51, 52) in response thereto. The first beam (51) is directed to a missile (7) to measure the angle and the distance of the missile and to convey piloting instructions thereto by modulation of said pulses, and the second beam (52) is directed towards a target (55) by a reflector (54) mounted on an aiming sight (22) in order to measure the distance to the target. The device further includes a computer (28) for determining the trajectory to be followed by the missile towards the target on the basis of the distances to the missile and to the target and on the basis of the angle between said distances.

Gas management transition device

Abstract: A transition region for a missile launch chamber providing a smooth transition from a generally square cross-section chamber in which a missile is stored and launched to a round exit opening of the chamber which connects with an exhaust manifold or plenum. The transition section is provided with a pair of pivoted doors for closing off the bottom of the missile chamber to prevent the flow of recirculation gases from the plenum into the chamber when a missile in another chamber coupled to the same plenum system is being fired. The portion of the missile exhaust chamber between the square cross-section and the circular exit opening serves to direct the exhaust gases of a missile being fired into a smooth round exhaust plume which functions as a "gas plug", preventing the recirculation of the exhaust gases back into the chamber of the missile being fired.

Penguin missile folding wing configuration

Abstract: An over-center locking mechanism is provided for a guided missile foldable wing structure which ensures stable reliable and non-reversible locking of the foldable wing. A pyrotechnic actuator is connected to the mechanism and, upon firing, quickly operates the mechanism to a deployed condition.

Method of launching a missile using secondary combustion

Abstract: In launching a missile from a launch tube, variable launch energy can be obtained by providing combustible products in the products of combustion from a gas generator and controlling the temperature and amount of oxygen present in the launch chamber to control the amount of secondary combustion in the launch chamber to provide a predetermined total launch energy and missile muzzle velocity.

High-speed missile with aerodynamic control

Abstract: The invention relates to a missile (1), especially a grenade which flies at supersonic speed, with aerodynamic control. The front part (V) of the missile (1) is supported such that it can pivot in all directions with respect to the remainder of the missile casing (2). An actuating device (10, 12) is provided in order to pivot the front part (V) of the missile (1) and in order to fix it in desired positions with respect to the missile casing (2). As a result, the flight path of the missile (1) is diverted in this pivoting direction.

Acceleration actuated kinetic energy penetrator retainer

Abstract: A retainer mechanism for releasably securing a kinetic energy penetrator tohe forward end of a missile while the missile is stored, transported and subsequently fired at a target such as a tank. The retainer releases the penetrator in flight responsive to acceleration acting on the missile, to reduce drag on the penetrator in its travel to the target.

Passive constraint for aerodynamic surfaces

Abstract: In a guided projectile such as a missile, it is often necessary to negate the lift force imparted by the wings (5) during early low velocity stages of flight. Thus, wings (5) can be flattened against the airframe (2) of the missile (1) by a passive constraint, e.g., a shrink tubing (35) which disintegrates due to aerodynamic heating at a higher velocity stage of the flight, allowing each wing (5) to deploy into a position generally orthogonal to the airframe (2). The deployment force can be provided by torsionally and compressionally preloaded springs (19).

Apparatus for correcting the flight path of a missile

Abstract: An apparatus for correcting the flight path of a missile, such as a high speed shell or projectile, includes a missile body with a distributor for flow means rotatable in the missile body. An outlet opening for the flow means from the distributor is positionable relative to a blow-out opening on the outer circumference of the missile body for effecting a correcting thrust and for switching rapidly between different transverse forces, a missile tip provided with the blow-out openings is arranged to communicate with the outlet openings from the distributor. The extent to which the blow-out openings and the outlet openings align or overlap can be adjusted by a drive for the distributor acting in cooperation with the braking arrangement.

Stabilised sub-calibre multi-purpose missile.

Abstract: The object is to provide a multi-purpose missile which after impact, without a complicated igniter, fragments during penetration into the target and has a high radial effect. To achieve this, the multi-purpose missile has a missile body (1) with an axial channel (2) which is closed at the front by a ballistic cover (3). Behind the ballistic cover is a piston (6) which is guided so as to be axially displaceable in the channel (2) of the missile body (1).

Missile separation system

Abstract: A missile separation system for fixedly attaching a rocket motor section a payload section has cofunctioning attaching and retarding means integrated to retain plural sections of a missile system in mated relationship until a predetermined point in the missile flight path.

Missile control systems

Abstract: A military offensive or defensive missile control system comprises drones or pilotted aircraft transmitting photographs of the battle zone to a receiving station (15, 16, 17, 20) where the photographs are suitably coded, identified and stored. A transfer mechanism (21) transfers a target image to each of a number of cruise missiles in launchers (22) mounted on a transporter (24). The missile when launched follows a set trajectory based on flight data recorded in its auto-pilot. The target image is suitably processed during flight to generate images of the target in various lanes and differing angles of approach. On nearing the target area, the photograph received by the missile's optical system is processed likewise by a master computer which also matches the two sets of images so as to lock the missile on to the target. The control system is housed underground beneath a reinforced concrete bunker roof (11).