SPECIFICATION OF THE INVENTION

1. Title of the Invention

Novel method for the generation of missile characteristic model and simulation of corresponding missile trajectory to track an airborne moving target in Air Combat Simulator environment.

2. Field of the Invention

The present invention relates to Air Combat Simulator, in particular related to the simulation of missile launch and its trajectory for training the pilots.

3. Prior art and Draw backs of prior art

The Conventional method of missile simulation used in Air Combat Simulator is limited to the simulation of a single type of missile only. Also the missile trajectory doesn't change dynamically as per the target maneuvering. It hinders the training of pilots in real time air combat scenario where dynamically moving airborne target is present.

4. Aim of the Invention

The primary objective of the invention is to provide a system and method for generation of missile characteristics and simulation of corresponding missile trajectory and hence to train pilots in following tasks:

• usage of different types of missile

• Target detection

• Missile Release

• considerations of Environmental conditions

• use of Electronic Counter measures

5. Summary of the present invention

The present invention is a novel method to simulate different type of missile operation for pre launch and post launch conditions. The present method of simulation of missile is achieved using four distinct modules, such as Missile modeler (101), Prelaunch Module (102), Missile Release module (103) and Post launch module (104). Missile Modeler (101) is a GUI based application which enables the generation of different missile models having different thrust and weight characteristics, drag characteristics and guidance and seeker characteristics and save the characteristics in the database. The Prelaunch module (102) simulates the operation of IR and Radar missiles when on board. It simulates the target detection, computation of dynamic Launch Zone (DLZ) parameters and displays the DLZ bracket on Cockpit Displays such as Head Up Display (HUD) and Multi Function Display (MFD) using the missile characteristics saved in database. Missile Release Module (103) simulates the missile release from the parent aircraft and displays the missile release in Out the Window (OTW) display. The post launch module (104) simulates the missile dynamics, effect of environmental conditions and electronic counter measures functionalities.

Brief Description of Drawing

Figure. 1 depicts the flow chart for Target detection by Radar missiles when on board.

Figure.2 depicts the flow chart for Target detection by IR missiles when on board.

Figure3 depicts the Dynamic Launch Zone bracket display on HUD.

Figure 4 depicts the flow chart for effect of Sun radiation on IR missile.

Figure 5 depicts the block diagram of the Missile Simulator System for simulation of missile functionalities.

Description of the Invention

A Computer based approach is employed in the present invention, for simulation of missiles of the advanced fighter aircraft. The present invention enables the generation of missile models, simulation of its operations in pre launch and after launch conditions. The present method of simulation of missile is achieved using four distinct modules, such as Missile modeler (101), Prelaunch Module (102), Missile Release module (103) and Post launch module (104). Missile Modeler (101) is a GUI based application which enables the generation of different types of missile models for simulation. It allows creation/modification of following missile parameters

• thrust profile (variation of thrust w.r.to time) of missile power plant

• weight profile (variation of weight w. r. to time)

• Drag profile (variation of co efficient of drag w.r.to Mach no).

• Guidance type - IR/Radar (semi-active or active) guidance.

• Missile seeker parameters which include missile seeker gimbals limit(pitch and yaw), missile seeker guidance range

• Minimum velocity to retain flight

• Cross section area of missile

• Control system initiation time

• Lethal radius of warhead

The above mentioned parameters are saved in missile database. Likewise different missiles can be generated which enables training pilots in dogfight and BVR fight scenarios. The Prelaunch module (102) simulates the operation of IR and Radar missiles when on board. The prelaunch module consists of cockpit simulation which includes the selection of master arm, late arm switches and missile selection switch. It also includes HUD and MFD simulation for the display of Dynamic Launch Zone bracket. It also includes the generation of audio cues to the pilot. The Prelaunch module (102) simulation starts with the selection of missile selection switch. First action in prelaunch module is target detection. Target detection is done in conjunction with Radar simulator model. The prelaunch module (102) computes DLZ from look up tables which are generated using simulated fly outs offline. The look up tables is generated with different sets of relative velocity, bearing and altitude of the target. Interpolation is used in real time during the simulation to generate results not found in the table.

Missile Release module (103) simulates the release of missile from the parent aircraft. The missile release happens by the selection of missile release switch in cockpit. It generates the audio simulation of missile release. It also generates the Out the Window (OTW) display.
The post launch module (104) simulates the missile trajectory towards the target, effect of environmental conditions and electronic counter measures. The dynamics of missile should include the missile motion, acceleration, and its thrust power. The line of sight angles should be used to find a target interception point. Therefore the extraction of missile acceleration commands to intercept the required target will be used to compute the velocity of missile (Vmissile) and angles of acceleration. ^missilew = * missilel*-" U + s* i^c missile*, v Where "Ac missile" is actual acceleration of missile and "st" is sampling time for measuring the acceleration. The first acceleration command "A1 missile" is dependent on the values of thrust, drag and mass values of target. This acceleration command works parallel to the velocity of missile (Vmissile).
A2missile(t) = CN^l(t) ^SmissileC1) = CN^IO) "A2missiie" and "A3mjssiie" are the second and third acceleration commands which work perpendicular to the missile velocity (V missile). "CN" is the proportional navigation constant, "cD1" and "02" are the projection angles of line of sight with respect to x- and y-axis.

The missile line of sight angle should be maintained with respect to the motion of target, Hence the missile velocity vector should rotate at a rate proportional to the rotation rate of the LOS-rate, and in the same direction. This will give rise to acceleration components perpendicular to the missile velocity. Using the velocity components in each direction, it computes the distance travelled in sampling time and computes the position. The missile motion is displayed in Out the Window (OTW) display. The post launch module simulates the effect of environmental condition such as position of sun on IR missile. Figure 4: Effect of sun's position on IR missile Post launch module also simulates the electronic counter measure on missile which includes flare for IR missile and chaff for Radar missile. When flare is released by the target, post launch module checks if flare is in missile LOS and if it is missile LOS, missile heads towards the flare. When chaff is released by the target, the Radar lock will be broken and missile misses target.
Post launch module simulates the missile hitting target when target is inside the lethal radius. It also displays the target hit in Out the Window (OTW) display. The invented Missile Simulator System is integrated with the Air Combat Simulator and provides a complete mission simulation of the fighter aircraft. The system is used for combat training of fighter pilots in the Air combat simulator system.

CLAIMS

We claim

1. An improved method and system for missile simulation in the Air Combat Flight Simulator comprising of missile characteristic model creation and simulation of prelaunch and post launch missile operations. The method and system for missile simulation in the Air Combat Flight Simulator comprising of Missile modeler (101), Prelaunch Module (102), Missile Release Module (103) and Post launch Module (104).
2. The method and system of claiml, where in the Missile modeler (101) enables the generation of missile characteristic models having different thrust and weight characteristics, drag characteristics and guidance and seeker characteristics.

3. The method and system of claiml, where in the Prelaunch Module (102) simulates the operation of IR and Radar missiles when on board. It simulates the target detection and computation of DLZ parameters.

4. The method and system of claiml, where in the Missile Release Module (103) simulates the missile release from the parent aircraft and displays the missile release in Out the Window (OTW) display.

5. The method and system of claiml, where in the post launch module (104) simulates the missile dynamics, effect of environmental conditions and electronic counter measures.