[1.1.2] Basic landing gear fixer

[Bedwyr]

Slashy, do you have a recommended tweak to dial back some of the nose-gear's resiliancy? I think it would probably work ok at a higher weight, but letting the gear fall on rollout after landing causes it to go into an uncontained bounce till it explodes. It's very amusing and it's only one part, but maaaybe I should split the difference?

Edit: and cheat the gear to indestructibility. Gah. I just discovered that my old strategy of doing Kerbin EVAs by ballistic parachute recovery won't work anymore. The gear need, probably, <5 m/s fall rate and I can only provide about 7 with five chutes.

Edited May 4, 2016 by Bedwyr

[Alshain]

@GoSlash27 Even with your patch, the gear still veers off the Runway quite a bit.  Not sure if there is anything you can do or not.

[frencrs]

4 hours ago, Alshain said:

@GoSlash27 Even with your patch, the gear still veers off the Runway quite a bit.  Not sure if there is anything you can do or not.

Dude you gotta just make sure to disable steering on the rear wheels and then you gotta Tokyo Drift the plane off the end of the runway.

[GoSlash27]

On 5/4/2016 at 8:06 PM, Bedwyr said:

Slashy, do you have a recommended tweak to dial back some of the nose-gear's resiliancy? I think it would probably work ok at a higher weight, but letting the gear fall on rollout after landing causes it to go into an uncontained bounce till it explodes. It's very amusing and it's only one part, but maaaybe I should split the difference?

Edit: and cheat the gear to indestructibility. Gah. I just discovered that my old strategy of doing Kerbin EVAs by ballistic parachute recovery won't work anymore. The gear need, probably, <5 m/s fall rate and I can only provide about 7 with five chutes.

Bedwyr,

 You should be able to reduce the spring rate with the slider to eliminate the bouncing. The setting in the tweak is a compromise between hitting the stops in normal use and invoking the kraken. Depending on the load, there may be some leeway there.

Other than that, yeah... nothing I can really do about it. The suspension travel of fixed gear (especially the nose gear) is extremely limited, and this requires extremely high spring ratios to keep from crashing the wheel into the strut in normal use. Those high spring rates cause an oscillation frequency that's too high for Unity to track smoothly, and creates a phantom force.

 I don't know how to render the gear completely indestructible, due to the instantaneous speeds it gets on impact and bouncing. Best I can recommend is to treat the basic gear as too weak for off- roading or impact absorbers. They're okay for airplanes (even out in the boonies), science carts/ trailers... stuff that doesn't need to be rugged.

Best,
-Slashy

Alshain,

 Yeah, nothing more I can do about that, unfortunately. Make sure you attach the gear using global alignment instead of local.

The gear will create some imbalanced forces no matter how they're adjusted, so the best I can do is choose how the imbalanced forces affect the aircraft in the most gentle way, which is veering.

Best,
-Slashy

 

[Bedwyr]

7 hours ago, GoSlash27 said:

Bedwyr,

 You should be able to reduce the spring rate with the slider to eliminate the bouncing. The setting in the tweak is a compromise between hitting the stops in normal use and invoking the kraken. Depending on the load, there may be some leeway there.

Other than that, yeah... nothing I can really do about it. The suspension travel of fixed gear (especially the nose gear) is extremely limited, and this requires extremely high spring ratios to keep from crashing the wheel into the strut in normal use. Those high spring rates cause an oscillation frequency that's too high for Unity to track smoothly, and creates a phantom force.

 I don't know how to render the gear completely indestructible, due to the instantaneous speeds it gets on impact and bouncing. Best I can recommend is to treat the basic gear as too weak for off- roading or impact absorbers. They're okay for airplanes (even out in the boonies), science carts/ trailers... stuff that doesn't need to be rugged.

Best,
-Slashy

 

Gotcha. Just to clarify my strategy was sort of like the Cirrus SR-22. Parachute down to an EVA site, pack the parachutes, take off like a normal airplane. Pre 1.1 that was a good way of not having to worry about difficult landings in tight spots.

[Alshain]

8 hours ago, GoSlash27 said:

Alshain,

 Yeah, nothing more I can do about that, unfortunately. Make sure you attach the gear using global alignment instead of local.

The gear will create some imbalanced forces no matter how they're adjusted, so the best I can do is choose how the imbalanced forces affect the aircraft in the most gentle way, which is veering.

Best,
-Slashy

Not sure what you mean by local or global alignment.  If you are talking about parent part vs vessel radial attachment, that doesn't apply to mirror symmetry.

Sadly veering isn't gentle either.  If I can't keep it on the runway long enough to build up speed, there is no point in flying a plane.  It's just frustrating that it's so close yet so far away from making planes in 1.1 usable.

Edited May 7, 2016 by Alshain

[nli2work]

was messing with these the other day... the Fixed gear is missing a suspensionPivot transform assignment... really really bad for ModuleSuspension. Add suspensionPivot = wheelPivot to ModuleSuspension {}, along with Slash's fixes, should improve the fixed wheel to a consistently usable point.

Edited May 7, 2016 by nli2work

[Alshain]

24 minutes ago, nli2work said:

was messing with these the other day... the Fixed gear is missing a suspensionPivot transform assignment... really really bad for ModuleSuspension. Add suspensionPivot = wheelPivot to ModuleSuspension {}, along with Slash's fixes, should improve the fixed wheel to a consistently usable point.

Doesn't seem to make any difference.

[GoSlash27]

1 hour ago, Alshain said:

Not sure what you mean by local or global alignment.  If you are talking about parent part vs vessel radial attachment, that doesn't apply to mirror symmetry.

Sadly veering isn't gentle either.  If I can't keep it on the runway long enough to build up speed, there is no point in flying a plane.  It's just frustrating that it's so close yet so far away from making planes in 1.1 usable.

Alshain,

Try that.

 If that doesn't get it, kick me a copy of your .craft and I'll see if I can spot anything else that'll help.

Best,
-Slashy

 

44 minutes ago, nli2work said:

was messing with these the other day... the Fixed gear is missing a suspensionPivot transform assignment... really really bad for ModuleSuspension. Add suspensionPivot = wheelPivot to ModuleSuspension {}, along with Slash's fixes, should improve the fixed wheel to a consistently usable point.

nli2work,

 That's brilliant! Incorporating it into the fix. How did you figure it out?

-Slashy

Edited May 7, 2016 by GoSlash27

[Alshain]

@GoSlash27 No luck.  Here is the craft.  It's a pretty standard conventional gear layout.  I can get this one into the air, it's just not ideal and landing it is very difficult.

Somehow, It's not surprising to me anymore that Squad would add a hidden feature like this without any on-screen indicator as to it's status.

Edited May 7, 2016 by Alshain

[GoSlash27]

Alshain,

Got it. I'm looking at it now.

-Slashy

[GoSlash27]

http://wikisend.com/download/207162/Alshain.craft

Alshain,

 Try this. I brought the mains closer to the CoG (still ahead of empty), Snapped them, the tailwheel, and the rudder to absolute. It still pulls a little left, but shouldn't be a problem for you now.

The mains seem to track better when close to the CoG.

Best,
-Slashy

Edited May 7, 2016 by GoSlash27

[Alshain]

I'm afraid that doesn't seem to make a difference.  It's still in the grass before it hits 40m/s.

Actually it is worse, with the gear at CoM, the plane will nose down once the rear gear lifts, so I can't even get it into the air at all before it explodes on impact.

Edited May 7, 2016 by Alshain

[nli2work]

1 hour ago, Alshain said:

Doesn't seem to make any difference.

Hm... you're right. Odd, difference was night and day when I was testing a couple days ago. must have been some other settings.

[GoSlash27]

Wow!

 There must be some radical difference between your setup and mine. This is the one I just gave you:

^ That's with absolutely no control inputs.

 Could you please send me a copy of your .cfg file for your fixed gears?

Thanks,
-Slashy

nli2work,

 could it be suspensionTransformName = suspension that's missing? I noticed that the free gear has it, but the fixed doesn't.

Best,
-Slashy

[Alshain]

4 minutes ago, GoSlash27 said:

Wow!

 There must be some radical difference between your setup and mine. This is the one I just gave you:

^ That's with absolutely no control inputs.

 Could you please send me a copy of your .cfg file for your fixed gears?

Thanks,
-Slashy

In 1.0.5, that plane is in the air before it reaches that point, with no control inputs.  I designed it to take off all by itself.  See how your nose is below the horizon?  That's why.  But I'm not even getting that far down the runway.

You want the configs from the Squad directory?

[GoSlash27]

1 minute ago, Alshain said:

You want the configs from the Squad directory?

Yes, please But just for the fixed and free gear. I want to see if there's a change I made that's not in the GearFixer.

-Slashy

[Alshain]

https://www.dropbox.com/s/cdpglj3uxdl7xmd/GearFixed.cfg?dl=0

https://www.dropbox.com/s/s9acj2z8sc4n7y5/GearFree.cfg?dl=0

[GoSlash27]

Alshain,

 That checks out. Nothing different in my .cfg files from stock. And you are using my 1.1.2 gear fixer for ModuleManager? Silly question, but I gotta ask...

Anything different at all between how you're flying it and how I'm flying it? Dirt runway, any trim adjustments, etc? Any mods you're using?

 

 

Edited May 7, 2016 by GoSlash27

[nli2work]

Ah yea, that's the one. suspensionTransformName =, don't know why I typed suspensionPivot =; it's in every single part that uses ModuleSuspension. the only one that doesn't have it is Fixed gear.

Edited May 7, 2016 by nli2work

[Alshain]

Slashy, nope.  Sandbox, no trim.  I'm using a flight stick but that shouldn't matter really since I'm not even touching it.

@nli2work I tried that too but no luck.

Thanks for trying guys, but I think I'm going to just stick with 1.0.5 for now.  I really tired of the pre-release testing.

[wasml]

Just looked at the landing gear folder - one (GearFree) has suspensionTransformName = suspension, and the others (minus GearFixed) have suspensionTransformName = SuspensionPivot.

OK - just imported into Blender and the GearFixed doesn't have a SuspensionPivot or a Suspension transform while the Gear Large does. Maybe they forgot the transform in the model itself?

[nli2work]

12 minutes ago, wasml said:

Just looked at the landing gear folder - one (GearFree) has suspensionTransformName = suspension, and the others (minus GearFixed) have suspensionTransformName = SuspensionPivot.

OK - just imported into Blender and the GearFixed doesn't have a SuspensionPivot or a Suspension transform while the Gear Large does. Maybe they forgot the transform in the model itself?

any object will work as the target, but it definitely needs a target assigned since there isn't a default value in the module. the best option in Fixed Gear is wheelPivot, the wheel mesh itself. is it me or is 1.1.2 worse than the prerelease as far as anything related to wheels go?

Edited May 8, 2016 by nli2work

[Alshain]

9 minutes ago, nli2work said:

any object will work as the target, but it definitely needs a target assigned since there isn't a default value in the module. the best option in Fixed Gear is wheelPivot, the wheel mesh itself. is it me or is 1.1.2 worse than the prerelease as far as anything related to wheels go?

1.1 was better than 1.1.1 or 1.1.2.  All it took to fix these gear for that is to add a little positive camber angle and they worked fine.  So far in 1.1.2 I haven't really had a very successful launch yet.

[nli2work]

I spent the last 6 hours wrestling with ModuleWheelDeployment. it's definitely worse than prerelease.