FAR Fighter Challenge: BD Armory AI

[Wanderfound]

Mod note: Thread locked at OP's request.

NOW MOVED TO A NEW THREAD: http://forum.kerbalspaceprogram.com/threads/135934-FAR-Fighter-Challenge-BD-Armoury-AI-2%21%21

Okay: time to add to the collection of AI fighter challenges. This one is focused on small fighter planes built for FAR, armed with direct-fire guns and missiles, in best-of-three one-on-one dogfights.

Entering is easy; just post a link to your .craft file, I'll run three dogfights with both planes under AI control (starting with both aircraft on the ground, one on the runway, one facing due west on the grass adjacent). Afterwards, I'll post the results as well as video highlights of the combat. The loser can choose to concede after one fight if the outcome is obvious. Whoever wins becomes the new defending champion, and holds the spot until defeated by a new challenger.

Your ship will need an AI pilot module from BD Armory, as well as a weapons manager. Autopilot altitude settings will be left at default+500m (i.e. min altitude 1,410m, default altitude 2,000m) to keep the planes together and give enough room to fight. Other autopilot settings can be altered. Keep in mind that dogfighting is a turning game, and excess speed makes turning slower. Also remember that Mach 3 at low altitude is generally suicidal from a heating point of view.

(edit to add: in order to keep the planes close together and to approximate the ability of a real pilot to increase their maximum speed as the circumstances dictate, fights will be run with maximum speeds matched as well as altitude. 399m/s will be the default maximum speed; this can be changed by mutual consent of the pilots if necessary)

Parts are limited to stock plus those found in the BD Armory mod [1]. The important [2] mods installed on the host machine will be as follows:

BD Armory (http://forum.kerbalspaceprogram.com/threads/85209-1-0-BDArmory-v0-8-3-(critical-fixes-improved-AI)-Dev-Thread-May-30)

Dynamic Deflection (http://forum.kerbalspaceprogram.com/threads/116888-1-0-The-Plugin-Workshop-Small-plugins-of-varied-function)

FAR (http://forum.kerbalspaceprogram.com/threads/20451-1-0-4-Ferram-Aerospace-Research-v0-15-4-1-Goldstein-7-29-15)

If you don't have all three of these mods installed on your game while you're building and testing your fighter, it won't fly as you expect during the fight.

Part clipping for aesthetic or aerodynamic purposes is fine; stacking three engines onto a single node is not. Engines are limited to turbojets/turboramjets; no reaction wheels or RCS (including Vernors) are allowed. Cockpit torque must be disabled.

All aircraft must be Kerballed; no drones. Normal HOTOL jets, not floating AA gun platforms etc. Weapons are limited to a maximum of six missiles per aircraft and as many direct-fire guns as you like (turrets must be locked if used). Defensive "weapons" such as chaff are allowed, but only one each of chaff/flare dispensers. Make sure that you test-fly your aircraft with the BD Armory autopilot before submitting it to ensure that it actually flies.

Rules are subject to modification in the interests of maximising fun if an un-fun dominating exploit shows up. Wheaton's law applies, but shouldn't be necessary. Leaderboards will be maintained in as many categories as seems appropriate.

[1] If you really want to fly with non-stock parts, that's fine, but you'll need to run the combat on your own machine. I'm keeping the part packs down to the minimum in order to minimise load on my CPU while recording video.

[2] There'll also be a few cosmetic things to improve the video (Kerbpaint etc) but those aren't necessary to build your ship.

Current Champion: Dwerto, D-9. Defeated K-3B1 Arctic Skua. Craft file at https://www.dropbox.com/s/f4uw6d6tv7fb7zv/d-9.craft?dl=0

Previous Champion: Doke, K-3B1 Arctic Skua. Defeated TE-11FS Shingo, K-35. Craft file at http://forum.kerbalspaceprogram.com/threads/132274-FAR-Fighter-Challenge-BD-Armory-AI?p=2214583&viewfull=1#post2214583

Previous Champion: TrainEngie, TE-11FS Shingo. Defeated D-6, CrisK Mini Flanker V2. Craft file at https://www.dropbox.com/s/7xii68bw6svl5j5/TE-11FS%20Shingo-Struts.craft?dl=0

Previous Champion: Dwerto, D-6. Defeated F-119C/A, K-3, Nabf-3. Craft file at https://www.dropbox.com/s/ojh75jh9m8vuz45/d-6.craft?dl=0

Previous Champion: Hodo, F-119C/A. Defeated MiK-6, ASK 1F-F. Craft file at https://www.dropbox.com/s/zrn8c74mwcdovwv/F-119CA.craft?dl=0

Previous Champion: Wanderfound, MiK-6. Defeated F-3C, F-152A, K-18, ASK 1F-F. Craft file at https://www.dropbox.com/s/5mxvjnihkmhgoxb/Kerbodyne%20MiK-6A.craft?dl=0

Previous Champion: Phearlock, F-3C Pidgey. Defeated MiK-3. Craft file at https://www.dropbox.com/s/wb2f5mibw9e4411/F-3C%20Pidgey.craft?dl=0

Edited October 6, 2015 by Supernovy

[Wanderfound]

And a demo vid (short, the loser made a mess of the first pass):

[xrayfishx]

Hehe, I've been building these things for a while now. I think I'll drop that MiK soon, I'll see to that tomorrow.

Also, I wonder when we'll see another one of these challenges with FAR and AJE. That would be an interesting sight.

[Wanderfound]

Hehe, I've been building these things for a while now. I think I'll drop that MiK soon, I'll see to that tomorrow.

Looking forwards to it; it'll give me a chance to roll out the MiK-5.

Also, I wonder when we'll see another one of these challenges with FAR and AJE. That would be an interesting sight.

Scott Manley's been talking about starting up his own one. No idea what mods he'll use, though.

If you toss in a Wheesley-based or no-missile fighter, I'd be happy to run those in separate categories. And I'm thinking of increasing the altitude a bit to reduce the frequency of autopilot dive-into-the-ground kills. I'll still keep it down in thick air, though; maybe just add 500m or so.

Edited August 25, 2015 by Wanderfound

[Wanderfound]

An entry for the gunfighter (i.e. no missiles allowed) division: https://www.dropbox.com/s/oh0waffikniqqil/Kerbofighter%20MiK-3%20GF%20C1.craft?dl=0

[xrayfishx]

A little update on my progress - it's hard to test my plane because yours falls apart by itself before mine can start fighting it.

[Wanderfound]

A little update on my progress - it's hard to test my plane because yours falls apart by itself before mine can start fighting it.

Working fine for me; see vid.

Do you have Dynamic Deflection installed? The MiK is designed for it; it'd over-control itself into aero failures at speed without it.

[xrayfishx]

Yeah, I do. But it seems to still snap after a few minutes of flying (if I'm lucky).

Some other news, I've forgotten how to FAR. The current prototype seems to oscillate and pull some 7G at best. If Proc Parts, BD wheels and B9 Proc Wings were allowed, I could try to convert some of my RO designs to work here. However those are a massive advantage against a plane that wasn't designed with these.

As it is I'm probably not going to take the throne today.

EDIT: Scratch that, a modified stock design worked.

Introducing LAF-1A Salomé.

Armed with two AIM-9 missiles, a Vulcan and capability to pull some serious G, this thing is perfectly capable of ruining your MiK-3.

Edited August 26, 2015 by xrayfishx

[Wanderfound]

EDIT: Scratch that, a modified stock design worked.

Introducing LAF-1A Salomé.

Armed with two AIM-9 missiles, a Vulcan and capability to pull some serious G, this thing is perfectly capable of ruining your MiK-3.

http://i.imgur.com/dN7C5jxb.png

Just ran a quick test flight of MiK vs LAF-1A.

* The LAF is nimble enough that it's very hard for the MiK to get clear once the LAF is on its tail.

However:

* The LAF autopilot turning settings have been wound up substantially from default, to the point where the LAF continuously overcorrects. It flies successfully, but is apparently in the hands of an extremely drunk pilot.

* The LAF intakes are set up so that one engine cuts out at around 10,000m. Replacing the intakes and engines in order (or using Intake Build Aid) would fix this.

In the test flight, the LAF managed to dodge the MiK's opening AMRAAM salvo. It then made it in behind the MiK, but the two planes engaged in an S-pattern turning duel that limited shooting opportunities. The LAF got one Sidewinder off at reasonably close range, but it was decoyed by the MiK's flares. Another long-range Sidewinder shot was simply outrun.

Eventually the MiK pulled into a spiralling climb. The LAF originally shadowed the MiK at low altitude, but then began to climb as well. As it passed 10,000m, one engine cut out, throwing its already wild piloting over the edge from manageable to unmanageable. It dropped into a subsonic stall and fell in a flat spin, blowing up in mid-air when it hit the lower atmosphere.

Did you want to tweak the handling before I run the full combat? Just pulling the autopilot turn settings back closer to default or reducing the control authority should do the trick (pulling the steer factor back to the default 14 stops the over-pitching issues, although it's still a bit roll-happy). The lower top speed relative to the MiK also makes it hard for the LAF to get within gun range (although I'd be happy to pull the MiK's top speed down to match the LAF; slower fights are tighter and better to watch on video).

If you want to see it in action, the video of a short bit of the test flight is at https://www.dropbox.com/s/nkb2tzzur3mj3ue/Wobbles.avi?dl=0

Edited August 26, 2015 by Wanderfound

[Wanderfound]

MiK vs LAF with speeds matched and LAF steer factor at default:

[xrayfishx]

Well, this is odd, it flew very nicely on my machine. Also, it was never meant to go to 10000m, I've never seen a fight go up so high, therefore I did not give it enough intakes to deal with that. I'll see what I can do to fix those issues and then try again.

Just to be sure, you do have the latest versions of the mods, right? I can't think of anything else that could explain what I saw in the video. This plane flew very differently on my computer. It mostly stayed at the speeds at which it was extremely maneuverable and it never climbed so high.

Edited August 26, 2015 by xrayfishx

[Phearlock]

How exactly are the fights set up? I'd like to know how you go about it, as I'd like to make something with a decent top speed, but I want to know how long it'll be up at altitude so it doesn't accelerate to insane speeds before it has to start turning.

[Wanderfound]

How exactly are the fights set up? I'd like to know how you go about it, as I'd like to make something with a decent top speed, but I want to know how long it'll be up at altitude so it doesn't accelerate to insane speeds before it has to start turning.

The flights are run on BD Armory AI, with the planes starting simultaneously, with one on the runway and the other in the grass facing 180° the other way (i.e. west). The planes are set to guard mode and autopilot standby. As soon as I change one of the planes to the opposing team, they both take off and fly to minimum altitude, then turn to engage.

For speed, the plane will accelerate to its autopilot-set maximum speed and then try to hold that. Transonic to low supersonic is generally best for dogfighting, and it's more fun if both planes are at the same speed. Too fast makes for slow turns and planes circling each other 10km apart.

If undisturbed, they'll fly at their default altitude (both minimum and default are set in the autopilot). But they'll climb to chase each other, and as all of these planes have the ability to climb vertically, it doesn't take long to get up high. They'll usually start with a low altitude skirmish, but if it goes past a few minutes it's common for one of the planes to try to run upwards.

If you build a plane that can take off, fly to 1,400m at a moderate angle (30-45°), then pull into a sharp turn (almost but not quite full stick) without flipping out of control or breaking up, it should work.

The plane needs an autopilot module to fly and a weapon manager to handle the gunnery. Both of those are in BD Armory. To test it, just set it on the runway, light the engines and activate the autopilot. Launch two planes on opposing teams (set this in the weapons manager) to see how they cope with turns.

We're using 500m higher than the default autopilot altitude settings; I'd suggest that you set the max speed to 400m/s and leave the other settings at default to start with.

--

xrayfishx: I'm using the latest version of the mods as far as I know, but I haven't checked them in the last week or two. Apart from FAR, Dynamic Deflection and BD Armory, I'm running Kerbpaint, Advanced Navball, Kerbal Flight Indicators, Kerbal Flight Data, Kerbal Engineer, Intake Build Aid, RCS Build Aid, Toolbar and Stock Bug Fix.

The LAF flies fine if you bring the autopilot turn rate back down to 14 (default). At that autopilot setting, it could probably even cope with having the pitch authority wound up a bit. The very slight remaining roll-happy tendency could probably be solved by converting the inner elevons to pure elevators (they're currently set for 50% roll and pitch;perhaps change them to 100% pitch 0% roll).

Fixing the intake thing is mostly just a matter of sharing them between the engines; at the moment, they're all assigned to give priority to a single engine. You might consider adding a pair of AMRAAMs while you're there, though; their longer range over the Sidewinders is giving the MiK the first shot advantage at the moment.

Edited August 27, 2015 by Wanderfound

[xrayfishx]

I started to muck around with the Salomé some more and it ended up breaking up mid-air as often as yours does, with no real improvements. So I decided to start work on a new design. So far everything seems to be awesome, except the AI can't keep its speed high enough, because it only has one engine. Also the AI can't take off without breaking the engine.

Also, in the video you posted it clearly didn't fly well at a turn rate of 14, it maneuvered like an oil tanker.

I'm really thinking that maybe it's a problem in my install that makes things break so easily.

What are the Dynamic Deflection settings on your MiK?

Edited August 26, 2015 by xrayfishx

[Wanderfound]

I started to muck around with the Salomé some more and it ended up breaking up mid-air as often as yours does, with no real improvements. So I decided to start work on a new design. So far everything seems to be awesome, except the AI can't keep its speed high enough, because it only has one engine. Also the AI can't take off without breaking the engine.

Also, in the video you posted it clearly didn't fly well at a turn rate of 14, it maneuvered like an oil tanker.

I'm really thinking that maybe it's a problem in my install that makes things break so easily.

What are the Dynamic Deflection settings on your MiK?

6G is pretty nimble for an oil tanker...but, yeah, there's another 4-6G to be had with some fine tuning. Cranking up the autopilot sends the yaw and roll control haywire; leaving the autopilot alone and adjusting pitch via control surface settings allows for more precisely targeted tuning. In the video, the LAF's main problem is that initial turn away from the missiles; if he'd turned into them and successfully dodged, the gunfight situation might have been reversed. The LAF certainly has the potential to beat the MiK.

I generally aim to have my plane just brushing the edge of a minor stall during the initial subsonic climb and turn. It also helps that I tend to use AoA-sensitive control surface settings; it allows the ship to crank hard at low AoA without flipping out at high AoA. This helps maintain supersonic high-G ability while reducing excessive AoA when subsonic and vulnerable to stalls.

I usually leave the Dynamic Deflection settings at default, although I may have cranked it up a smidgeon while tuning the MiK-3; I'd need to check.

Are you running this on your normal install, or did you set up a fresh one with just FAR/DD/BDA? Apart from FAR and DD, the only mod I'm running that I can think of that might make a difference is Stock Bug Fix. That does adjust the joint strength on a few parts.

Edited August 27, 2015 by Wanderfound

[Wanderfound]

Experimenting with the MiK-4...

Winding the Dynamic Deflection authority up to max on the elevators is definitely worth it. It lets you keep high-power pitch control at speed without overcontrolling during takeoff.

The current version has elevators with deflection of 40, AoA 100 and maximum authority. The basic airframe is similar to the MiK-3 with a bit more wing. It'll do up to 11G on default autopilot settings; it might be possible to get a touch more out of it by shifting the main wing forwards a smidge.

Edited August 27, 2015 by Wanderfound

[Wanderfound]

MiK-3 vs MiK-4:

[CommanderCoye]

Pretty sure if I took on this challenge my lazer prototype would be obliterated by more seasoned craft. I'll give it a try.

[Wanderfound]

Pretty sure if I took on this challenge my lazer prototype would be obliterated by more seasoned craft. I'll give it a try.

The more the merrier.

[CommanderCoye]

The more the merrier.

Cool, I'll get right to some more tests. I've also found a missile evasion technique.

[SpaceplaneAddict]

Alright, I've been developing this for a while, and today's the day to show it! Apparently is looks somewhat like an f-16, so yeah! Presenting, the twin-engine K-16 Phoenix

Armed with two hidden Vulcans and six AMRAAMs, this fighter will fly with grace. Very hard to stall, no matter what I do! Good luck, my dear Phoenix... Craft File:https://drive.google.com/file/d/0B588M8xKv0QKTkg2VVJlUE5wbEk/view?usp=sharing Edit: Those radial intakes keep falling off, asymetric thrust,I think i may need better intakes for high altitudes. Wish me luck!

Edited August 27, 2015 by SpaceplaneAddict
A small update on problems with my fighter

[Wanderfound]

Alright, I've been developing this for a while, and today's the day to show it! Apparently is looks somewhat like an f-16, so yeah! Presenting, the twin-engine K-16 Phoenix

Armed with two hidden Vulcans and six AMRAAMs, this fighter will fly with grace. Very hard to stall, no matter what I do! Good luck, my dear Phoenix... Craft File:https://drive.google.com/file/d/0B588M8xKv0QKTkg2VVJlUE5wbEk/view?usp=sharing Edit: Those radial intakes keep falling off, asymetric thrust,I think i may need better intakes for high altitudes. Wish me luck!http://i.imgur.com/aowaO8V.png

Cool.

Quick testflight notes:

* The buried structural intakes explode when I load the ship. Probably best to relocate those somewhere unclipped.

* Using Intake Build Aid (or placing the intakes in order, see http://forum.kerbalspaceprogram.com/threads/84217-Explaining-burnout-asymetry) will solve your high-altitude issues.

* It takes off and flies succesfully, all good there.

* You probably want to give it some more pitch authority; at the moment, it's only pulling about 4G in the turns (vs the 6G LAF, 9G MiK-3 and 11G MiK-4).

* What do you want your takeoff and maximum speeds set to?

[SpaceplaneAddict]

Cool.

Quick testflight notes:

* The buried structural intakes explode when I load the ship. Probably best to relocate those somewhere unclipped.

* Using Intake Build Aid (or placing the intakes in order, see http://forum.kerbalspaceprogram.com/threads/84217-Explaining-burnout-asymetry) will solve your high-altitude issues.

* It takes off and flies succesfully, all good there.

* You probably want to give it some more pitch authority; at the moment, it's only pulling about 4G in the turns (vs the 6G LAF, 9G MiK-3 and 11G MiK-4).

* What do you want your takeoff and maximum speeds set to?

I see:confused:. Looks like I'll be adding another mod to my list. Take-off speed is around 110-120 m/s, and this can handle sustained 800 m/s flight. I'll work on pitch authority, any suggestions?

[SpaceplaneAddict]

Brand new issue, this sucks;.;. I've managed to pull 11.5G, with a brand new drawback. Stalling out. And the nooby issue of raw thrust comes into play...

[Wanderfound]

I'd suggest raising the DD control authority and boosting the deflection on the elevators to increase pitch authority, and adding some positive AoA deflection to reduce the high-alpha stalling tendency. Maybe pull the main wing rearwards a bit as well. You may also need to shift the rear gear back/down to avoid clipping the engines in a more vigorous takeoff.

There's also the point that those intake boxes are adding a lot of weight without improving performance; they're cosmetic rather than practical. You'd be better off just having flat wings and leaving the intakes in the open. You might also want to consider shifting to an all-moving tailplane (AV-R8, Tailfin, Canard); conventional elevators don't work well once supersonic.

Setting maximum speed isn't about what the plane can take, it's about what speed it has the best turning performance at. You want as low as possible without stalling out. 399m/s works well to start; it's what I've been fighting the MiKs at.

PS: see the link in my sig for the race challenge. A good fighter is basically just a racer with guns; if you can build something that works for one, it'll work for the other.

Edited August 28, 2015 by Wanderfound