Landing Gears are Broken (and unusable for some things)

[[ISFYLG]HenchmanAce]

This applies more to smaller vehicles but can still affect some bigger crafts.

1. Lets start off with the bouncing landing gear glitch. Ever since suspensions were added, landing gears cause crafts to start bouncing uncontrollably, sometimes cause the vehicles to break apart on the runway. I've tried adjusting dampner and spring setting but that only reduces a problem that shouldn't exist to begin with, but doesn't actually fix it and setting the spring to 0 makes my plane shake when I start moving on the ground to the point that I lose control.

2. The fixed landing gears (LY-01 and LY05); they suffer from the bouncing glitch too but their biggest problem is the fact that they break for no reason. On landing, if I come in with a vertical velocity over 1 m/s (which is almost certainly going to happen with certain, more unconventional designs), even if the aircraft is light and going slowly, the gear just explodes, leaving my plane to crash. When I check the logs afterwards, it says that the landing gear crashed into the ground/runway. It doesn't say that the wheels were overstressed, it says that it crashed. These landing gears are rated to hit at speeds of 125m/s so why do they keep breaking for no reason?

3. Landing bounce of death: So this happens if I use retractable landing gears with some smaller aircraft, when I come in for a landing and my back wheels (main gear) touch down, it sends the back of the plane back up and sending my plane into a nose down attitude, where it crashes into the ground nose first, destroying it. It does from whatever flare angle of attack I had to negative 20-30 degrees because for some reason, touching down on my main gear sends launches the back of my plane into the air. Adjusting the suspension sliders does nothing.

So yeah, this has been a problem for 1.5-2 years and it still hasn't been resolved. Please fix it, it's the most infuriating thing in this otherwise bug free game.

[Lystent]

Well, they may be rather limited, but they are:
-Adjustable
-Capable of going down low
-Small craft friendly
https://steamcommunity.com/sharedfiles/filedetails/?id=1501799628

Edit: and I also just realized that this is the wrong thread, but same point.

[RoofCat]

Originally posted by MrTassadarzo:

I am experiencing this same bug with Rovemax M1 wheels on a Minmus rover. ... I have also launched the rover to orbit with its vernor engines and brought it back down to the surface, but after landing the bouncing simply continues.

vernon engines+fuel... how heavy is your rover exactly and can you share a picture when making bug claims? Why are people complaining so shy - you think not posting images will help solving your issues faster?

[Lystent]

Probably because they do not want to play 101 questions of 'are you sure it is a bug?'...
Long story short, I am sick of that game too.

[RoofCat]

why? I went testing my rovers, keeping constructive attitude. You don't want solution, you just want to cry?

The thing is I don't use rovers daily - too slow for my taste. But of course I have created some over the years. So I sent some to Mun for even more thorough tests.
My express conclusion - wheels are slightly stickier now. Not by much, but noticable. Reduced friction a bit to avoid rolls on Kerbin. I prefer drifting any time of the day.
Due to that there are some slightly weird issues, like after loading with handbrake-on on Mun once the rover was somehow balancing on front wheels at roughly 20° (tail up). I did a few loadings to test, but that was rather random and sometimes there was just a very light hovering of the tail. The rover was standing on slight slope front pointing down. Maybe that contributed a bit, but the position was weird anyway. Even with powerful handbrakes it should simply roll over the wheel surface despite them being fixed on axis. Rubber glue issues I guess.

But I didn't witness any oscillating issues or jumping so far - with the 4 Rovemax M1 wheels on a 1.7t rover.

Adjusting rover suspension in space is problematic. First it is not possible to do outside of the VAB/SPH in stock game except you go into file editing or for friction. And then the theoretical side sucks too. Because while rover has only 1/6 weight (kN) on Mun due to less gravity and thus has different ground clearance just standing around, it still has exactly the same inertia while moving around. So it can create the same overloads while driving - just like on Kerbin, but the force keeping it down is different. It might be tricky stuff to grasp and adapt.

[Lystent]

Originally posted by RoofCat:

why? I went testing my rovers, keeping constructive attitude. You don't want solution, you just want to cry?
...

Or perhaps we are tired of sidestepping the problem and want it to be clear that something isn't behaving the way it should.

Edit: for me, I have a accumulated a list or workarounds that each have their weaknesses;

-Increasing weight has its obvious costs in various ways.
-Smaller gear give less room for suspensions to collapse before the belly hits the deck.
-Angled gear (vs. larger gear) geenrates problems without known workaround.
-Bigger gear (vs. angled gear) generates problems that leads to other workarounds.
-Pylons are too lacking in variety to always be a solution w/o cost.
-Higher dampers is the the best for me, but the gear will still hammer when crushed.
-Lower dampers+springs leaves the gear closer to crushing/hammering.
-Skis only work at slow speed and a more limited angle and add drag without protection.

[Manwith Noname]

I was going to post in the other thread as it was that discussion which encouraged me to look at things for myself, I won't go into everything I've read and discovered but I'll just post this and say...

https://steamcommunity.com/sharedfiles/filedetails/?id=1501972453

I made that craft in multiple versions of KSP and most pertinently, in 1.4.1 (and older versions but this one is probably the most important) it loads to the runway and sits fine and dandy no issue. In 1.4.5, it bounces around like it's at a hip hop gig.

This is a chicken wing...

https://www.youtube.com/watch?v=tLUaycJFjWA

Edit: Figured I would read the patch notes again...

* Improvements to wheels/legs bouncing/sliding and oscillations. (Particularly when overloaded).

Heh.

[RoofCat]

Originally posted by Manwith Noname:

I was going to post in the other thread as it was that discussion which encouraged me to look at things for myself, I won't go into everything I've read and discovered but I'll just post this and say...

https://steamcommunity.com/sharedfiles/filedetails/?id=1501972453
I made that craft in multiple versions of KSP and most pertinently, in 1.4.1 (and older versions but this one is probably the most important) it loads to the runway and sits fine and dandy no issue. In 1.4.5, it bounces around like it's at a hip hop gig.

Edit: Figured I would read the patch notes again...

* Improvements to wheels/legs bouncing/sliding and oscillations. (Particularly when overloaded).

Heh.

I went a bit further. Because this bouncing reminded me of what I said earlier - now it feels a bit more 2D, while earlier it was mostly from side to side. Of course, in this case that's also rover design with 4 wheels and mass in the middle, but still. It makes me think it is not or not just wheels these days. I was aware of slightly different surface colliders, so I snapshotted this spot just in case. Wheel submerge at runway start compared to later or plains doesn't solve the bouncing though. And it is slightly random each time
https://steamcommunity.com/sharedfiles/filedetails/?id=1502186835
Then I did few tests with springs and dampeners and obviously you can make it cool down. But...
Let's just say, try to turn on Physics warp. Even more so with increased dampeners. Is the gravity growing during Alt+. ? It's a known issue of part displacements and reason for tear for years. But the thing it turns bounce into crash makes me think more about that crash module.

So I'm not convinced the issue is with springs and dampeners. At all.
They still react to adjustments like they did earlier. But they have to fight something. Even more than before. Rigid bodies just don't notice that force, but my best guess is it's there everywhere for everything. What the hell is that something? They have adjusted collisions a few patches ago. There were issues. They solved it with probably just a workaround, that actually transfered the issue to something else, something less protected like wheels.

Or break legs on your rover, make it flip, turn on phys warp and see it jitter as intake gets compressed by tanks. Is the gravity in phys warp higher? It is also not a new issue, but I still think there is a lot more going on than what meets the eye of Sunday gamer.

[Toastie Buns]

Originally posted by ISFYLGHenchmanAce:

Originally posted by Toastie Buns:

Wheels are bouncing, but a nose first landing is a sign of a bad plane.
Trust me, I make lots of bad planes.

My designs are good.

Lol, k then. I think your issue may be with clipping, but whatever. That's why my planes nose firsted on landings, my quest for perfectly level gear clipped the nose wheel too far in. Bigger gear on the rear fixed this, allowing the smaller gear to be placed on the nose and be equal in height.
Be aware that solution creates a serious weak point at the nose that now introduces a slight yawing on take-off, but it is what it is. We'll never know until you screencap the issue.

PS: I am not contesting physics bounce or jittery wheels. I know they're a thing. I'm all about the nose first landing.

PPS: When I tested my planes to fix them back then, I kept them on the runway, accelerated and braked. This let me fix the nose first situation. Waaaaaay quicker than takeoff and landing. (This was in a version with universally agreed upon broken wheels lol)

[Manwith Noname]

Originally posted by RoofCat:

So I'm not convinced the issue is with springs and dampeners. At all.
They still react to adjustments like they did earlier. But they have to fight something. Even more than before. Rigid bodies just don't notice that force, but my best guess is it's there everywhere for everything. What the hell is that something?

In my faffing around and reading trying to do something I stumbled upon a comment regarding how the stock suspension does its thing. Apparently it auto adjusts based on load / mass, which makes sense when you look at the module setup in the configs with some of the parameter naming.

My guess is, the 1.4.5 patch altered something in the way this works and with the current settings on those wheels it gets stuck in a loop trying to find a balance for the load which makes it bounce up and down.

I also played with the config for those wheels. If you adjust the boost ratio from 0.75 to 0.5, it will settle after some mild bouncing from memory. I highly recommend making auto boost true for the giggles mind you.

[RoofCat]

other wheel types don't have boost ratio or auto boost flag. One has it commented out, the rest none at all (deleted). Some have target position at 0, some at 1 or 0.8. I don't really see a clear pattern there, but it is obvious KSP has used quite a few different handles to get wheels behave or look properly at some point in the past.

I do restart KSP each time I adjust cfg. And it wastes a lot of time. So I'm not really interested to dig much further on my own. Is that restart needed or can you reload resources some other way - some cheat console command or just rebuilding something will re-read the cfg file? I have always assumed KSP loads most of the stuff in memory at launch already.

[Operation40]

Originally posted by RoofCat:

some cheat console command or just rebuilding something will re-read the cfg file? I have always assumed KSP loads most of the stuff in memory at launch already.

alt+f12 -> database -> reload database

but it reloads everything so still takes a while.. maybe will help a little though

[Manwith Noname]

Originally posted by RoofCat:

other wheel types don't have boost ratio or auto boost flag. One has it commented out, the rest none at all (deleted). Some have target position at 0, some at 1 or 0.8. I don't really see a clear pattern there, but it is obvious KSP has used quite a few different handles to get wheels behave or look properly at some point in the past.

Yeah, I have noticed this. I guess the thing is some of the issues don't necessarily show at all times, or at all with all gear in the same way. It could just be as simple as there was previously a problem with the fixed gear, so the module was adapted and / or extra parts of the module were configured. It not being defined for other gear just means they didn't engage it for them.

At some point I was going to play with the wider range of gear and the various parameters some more but I really wanted to find descriptions of their intended behaviour. I did try looking but the wiki doesn't appear to have been updated with the new wheel system definitions....or at least I only found the old ones and at that point I stopped looking under that assumption.

Originally posted by RoofCat:

I do restart KSP each time I adjust cfg. And it wastes a lot of time. So I'm not really interested to dig much further on my own. Is that restart needed or can you reload resources some other way - some cheat console command or just rebuilding something will re-read the cfg file? I have always assumed KSP loads most of the stuff in memory at launch already.

As above, debug menu allows you to reload the database. Module manager has a similar feature, which I think is because the stock debug menu wouldn't reload MM patches. So if you make edits via module manager patching, you'd need to use the module manager reload. I've also got a memory of more than one type of reload option, which might only be to reload patches....I should really check this as I use it....

I also noticed this mod pop up a while back...

https://forum.kerbalspaceprogram.com/index.php?/topic/173015-142-chrononaut-v041-part-mod-tool/

I haven't tried it but it is specifically made for selective part reloads. Don't know if it would pick up module manager patches.

[Panzer Elite]

I know this is old thread but I can't ever land with LY-01 fixed landing gear, I tried so many designs. Tried making the plane lighter, landing slower, and my angle of descent. Idk if this is a bug or I'm a scrublord.

[Manwith Noname]

You didn't mention spring strength or damping, so they might still be able to help. I can't recall if they are visible by default or if you have to enable advanced tweakables in the options.

Otherwise, the sooner you can get away from fixed gear the happier you and your craft will probably be.

[Panzer Elite]

Originally posted by Manwith Noname:

You didn't mention spring strength or damping, so they might still be able to help. I can't recall if they are visible by default or if you have to neable advanced tweakables in the options.

Otherwise, the sooner you can get away from fixed gear the happier you and your craft will probably be.

I don't think the fixed ones has any spring strength, I'm just not going to do any planes until I get better landing gear, that's the good option. In sandbox I was able to land with the builds they have in there. And what do you mean by damping going up and down to reduce speed?