ACE3/documentation/framework/advanced-missile-guidance.md

layout	title	group	order	parent
wiki	Advanced Missile Guidance	framework	5	wiki

1. Overview

The ACE Advanced Missile Guidance Framework provides a setup of configuration settings, functions and a execution framework for addon makers to integrate with the missile guidance and targeting mechanisms of ACE. It also provides for mod makers to create their own custom guidance methods within the framework.

The framework provides all the functionality needed for guidance; from laser locking, target specification and selection, to handling the fired events and tracking and steering the vehicle based on provided parameters. This way, all that needs to be defined in addons is the appropriate CfgAmmo entries for the missile.

The framework also provides addon makers and scripters with the ability to configure custom seeker types and attack profiles, which are defined below. This allows for complete control of the guidance, locking and flight of a missile at the discretion of the addon maker.

ACE3 provides a full suite of base concepts and guidance for the majority of modern missile weaponry avialable today; these includes all basic types of seekers (SALH/SACLOS/Optic/Thermal/etc) - as well as the different common attack profiles utilized with guided munitions (such as top-down attacks).

Finally, flight profiles and mechanics for realistic missile simulations are also implemented; allowing for lock-steering bump guidance flight such as with the M47 Dragon or GBU steering fins, or finely tuned direct flight guidance which is currently avialable with other missile types.

2. Details

The framework is broken up into 3 major components: Locking Types, Seeker Types and Attack Profiles. In combination, these components build out the entire process of launching, locking and going terminal flight against targets.

Components

1. Locking Types

Locking types provide the basic functionality of targeting which will be based to a seeker type, providing target aquisition for seekers. This provides the basic functionality for providing pre-determined targets for a seeker, or allowing the seeker to perform its own target aquisition and locking. Additionally, the seeker may reference back into the locking type in order to re-perform target aquisition.

2. Seeker Types

Each seeker is generally assumed to be the logic for the seeker head unit within any given munition. Seekers within this framework provide the basic targeting functionality for the entire framework. The locking type will provide a generic target to the seeker, or the seeker may aquire a target on its own. The seeker then provides a target, either an object or a ASL position, which is then passed further into the framework. This target (or position) should be the actual current target position for the missiles flight. Seekers are required to perform all limitations and checks within their systems, although various limitations have been provided in this framework such as LOS FOV, laser guidance, etc.

3. Attack Profiles

An attack profile adjusts the current target flight location to create the actual flight path of the missile. The attack profile is provided with all parameters of the system, including the returned target of the seeker. Using this information, the attack profile then will adjust the direct flight target position to specifically direct where and how the missile shall flight.

How it all ties together

The system is executed in a linear series of calls to each step of the process, and feeding back the return from that step to the next step. Execution is conducted using Locking->Seeker->Profile, iteratively every frame of execution. Flight times are adjusted to accTime values and FPS lag, giving consistent flight.

On each step of execution, a target specification array [targetObj, targetPos] is passed to the locking type, which then will return a possible modified target array. Next, this modified data is passed to the seeker type - which then, in turn, returns a position vector to the current "seeked" target position (ASL). Last, this target position is passed to the attack profile, who then returns an "adjusted attack position (ASL)", which is the location the missile should currently be homing on for flight.

In the simplest sense, the entire system provides the flight trajectory of the missile homing directly on the "adjusted attack position"; thus, an attack profile would ajust this position to direct the missile. For example, Top down attacks return the adjusted attack position high above the target, until entering their terminal stages, which then changes the position to be directly ontop of the target - thus "walking the missile" along its flight path and to the kill.

2. Adding AMG to a missile

Enabling guidance on Ammo Types

class CfgAmmo {
    class MissileBase;
    class MyMissileType : MissileBase {
       // Turn off arma crosshair-guidance
        manualControl = 0;
       
        // Begin ACE guidance Configs
        class ace_missileguidance {
            enabled = 1;
            
            minDeflection = 0.00025;      // Minium flap deflection for guidance
            maxDeflection = 0.001;       // Maximum flap deflection for guidance
            incDeflection = 0.0005;      // The incrmeent in which deflection adjusts.
            
            canVanillaLock = 0;          // Can this default vanilla lock? Only applicable to non-cadet modes. All 'recruit' games use vanilla locking
            
            // Seeker type and settings for munitions
            defaultSeekerType = "SALH";
            seekerTypes[] = { "SALH", "LIDAR", "SARH", "Optic", "Thermal", "GPS", "SACLOS", "MCLOS" };  
           
            defaultSeekerLockMode = "LOAL";
            seekerLockModes[] = { "LOAL", "LOBL" }; 
            
            seekerAngle = 90;           // Angle in front of the missile which can be searched
            seekerAccuracy = 1;         // seeker accuracy multiplier
            
            seekerMinRange = 1;
            seekerMaxRange = 2500;      // Range from the missile which the seeker can visually search
            
            // Attack profile type selection
            defaultAttackProfile = "LIN";
            attackProfiles[] = { "LIN", "DIR", "MID", "HI" };
        };

2. Creating your own custom seekers and attack profiles

Adding seeker types and attack profiles

class ace_missileguidance_attackProfiles{
    class MyAttackProfile {
        name = "";
        visualName = "";
        description = "";
        
        functionName = "my_fnc_doAttackProfile";
    };
};
class ace_missileguidance_seekerTypes {
    class MySeekerType {
        name = "";
        visualName = "";
        description = "";
        
        functionName = "my_fnc_doSeekerType";
    };
};