Is Autostrut an in-game cheat?

[Wcmille]

I don't see a downside in autostruting. It doesn't seem to affect mass, and improves the rigidity of the craft. Feels like entering a cheat code.

 

What's the intent of this feature?

 

[Jas0n]

To help reduce part count is my guess. And you don't see real life rockets that are covered with struts. 

I'm perfectly fine  with autostruts, but if you're not you can turn them off.

[Spricigo]

 

I will replay that with a question: who is the one being cheated?

 

And "improves the rigidity of the craft" kinda miss an important point: you don't want your craft to be too rigid. Just ask someone that loaded a large base to see it disassemble for no apparent reason.

 

But yes, a extructural element that cost nothing and weight nothing its not exactly 'realistic'.

 

 

[OHara]

The history as I understand it:

Suppose you have a rover/probe/lander in a cargo bay.  It might flop around in the bay, moving through the walls or even breaking off its attachment point.  The obvious solution is to strut it to the bay, letting the struts break when you decouple the rover.

However, if you re-dock the rover/probe/lander, the stock game gives no way to recreate the struts.  The rover might break off its docking port on the next leg of the journey.  Re-dockable craft tend to have wheels or landing legs, so KSP 1.1.1 automatically strutted wheels and legs to the heaviest part.  Upon re-docking, the wheels are rigidly attached to the heaviest part of the newly-joined craft. 

Working around difficulties with the physics of wheels might have been another motivation to implement autostruts.

Players at least imagined abusing these autostruts by placing wheels just to get the autostruts.  Also, autostruts don't solve re-docking situation where the probe doesn't have wheels/legs.  Version 1.2 made auto-struts an option for all parts.

If you are even asking whether autostruts are a cheat, I suppose that designing craft that are sufficiently stable is part of the game for you.  In that case you'll probably want  them only when a massless dragless attachment would be realistic, such as tension lines securing a probe in a cargo bay.

[HebaruSan]

4 hours ago, Wcmille said:

What's the intent of this feature?

The new wheels starting in 1.1.0 caused planes to spontaneously break apart on the runway. I don't know the detailed reasons, but essentially if you put your landing gear on anything other than the central heaviest fuselage part, those parts would rip off and the fuselage would fall to the ground and explode. In response, SQUAD created auto-struts to anchor landing gear to the heaviest part as a workaround in version 1.1.1.

http://wiki.kerbalspaceprogram.com/wiki/1.1.1

Then some streamers started abusing landing gear to make their space stations more stable. Auto-struts were added to all parts in the 1.2 release to discourage space stations covered in landing gear.

http://wiki.kerbalspaceprogram.com/wiki/1.2

[bewing]

KSP uses the Unity engine, and Unity uses PhysX. These libraries have bugs -- especially in the spring equations in "wheel" physics (which includes landing legs), and in the undamped springiness and noodlyness of joints between parts. Those two libraries are closed source, and the KSP devs cannot fix their bugs. These bugs have existed for a long time, and everyone hopes they will eventually get fixed by the owners -- but they have not been fixed yet. Squad understands that these bugs would make KSP unplayable if unremedied. The devs added the VehiclePhysicsPro library, autostruts, the brake friction UI, and the suspension spring & damper UI as intentional kludges to mitigate the bugs in the game engine as much as humanly possible. There is some intention of removing all these kludges if/when the underlying bugs get fixed. So I'll be slightly pedantic and quibble about the terms "cheat" vs. "kludge".

 

[Bottle Rocketeer 500]

5 hours ago, HebaruSan said:

Then some streamers started abusing landing gear to make their space stations more stable. Auto-struts were added to all parts in the 1.2 release to discourage space stations covered in landing gear.

LOL, I've never seen a space station in KSP covered in landing gear.

[PT]

47 minutes ago, Bottle Rocketeer 500 said:

LOL, I've never seen a space station in KSP covered in landing gear.

Because most sane station builders use KJR.

[magnemoe]

General its an very good thing, joints in KSP has an pretty low bend resistance and its hard to make re docked structures stable.  Real world structures are more rigid,

As anything it can be abused, pretty easy to make things who would not hold up because of auto strut.  You can always use standard struts for the look and I think they are stronger.

[Curveball Anders]

1 hour ago, PT said:

Because most sane station builders use KJR.

I prefer the middle way and use EVA Struts

So I add strut 'stubs' around connection nodes and after I've docked a new part/module/gizmo/gerät to a station (or ship assembled in orbit) I lob a kerbonaut out on EVA to strut the connection.

To me it feels like a good balance between reality and kerbality.

[Snark]

Moving to KSP Discussion, since this is really about discussion & opinions about the game design, rather than an actual gameplay question.

[tseitsei89]

No it's not a cheat. Plus there is certainly a downside: if you use too much/too long autostruts in big crafts they will just spontaneously start to shake and finally just blow up.

I think autostruts are there for 2 reasons:

1. Reducing part count and lag on bigger lifters since you dont need a s**tload of struts because you can autostrut.

2. They are a good way to reinforce your stations/interplanetary motherships built in orbit. Docking connections are often quite wobbly and you cant place struts to make them stronger once in space. (Another good solution to this problem would be making kis/kas kind of features stock so you could strut with kerbals on EVA, but squad decided to solve the problem this way which is also fine).

[regex]

On 8/2/2017 at 1:45 AM, bewing said:

There is some intention of removing all these kludges if/when the underlying bugs get fixed.

DONT YOU DARE REMOVE DETAIL!

I seriously shouldn't have to be worried about this, but suspension tweaking should remain in the game, as should any tweakables, unless that has been added back in an additional feature that the player has direct control over.

Edited August 4, 2017 by regex

[Alshain]

Yes, yes it is.

 

... but if you don't care, there is no problem.

[cubinator]

58 minutes ago, regex said:

DONT YOU DARE REMOVE DETAIL!

I seriously shouldn't have to be worried about this, but suspension tweaking should remain in the game, as should any tweakables, unless that has been added back in an additional feature that the player has direct control over.

The thing about the wheel and landing gear tweakables is I don't know what they do. Is there someplace I could find out and learn how to use them other than trial and error?

[regex]

Just now, cubinator said:

The thing about the wheel and landing gear tweakables is I don't know what they do. Is there someplace I could find out and learn how to use them other than trial and error?

I learned about them by reading the VPP API and I'm pretty sure there's a guide or two around these parts. Regardless, that's no reason to remove them from the game. I see no problem with having them auto-configured once the bugs are worked out but removing that sort of detail once it's in the game is literally blasphemous.

[cubinator]

Just now, regex said:

I learned about them by reading the VPP API and I'm pretty sure there's a guide or two around these parts. Regardless, that's no reason to remove them from the game. I see no problem with having them auto-configured once the bugs are worked out but removing that sort of detail once it's in the game is literally blasphemous.

Sure, I just need some direction on how best to use them for a variety of craft (including Rubik's Cubes) and then I can fiddle with them and make them useful.

[regex]

55 minutes ago, cubinator said:

Sure, I just need some direction on how best to use them for a variety of craft (including Rubik's Cubes) and then I can fiddle with them and make them useful.

Amazingly I can't find a tutorial around here.

Springs support the craft on the wheels, the slider determines their strength (greater being stiffer springs).

Dampers dampen the spring action so that the craft doesn't "float" on the springs, the slider determines their strength (greater being quicker dampening).

Traction control and friction control are a bit of a mystery to me, although setting the friction control lower on the back wheels can be fun. Setting friction control higher will make the craft stick to the ground better but could lead to flipping? Traction control I think has more to do with drivetrain limiting, that is they won't unnecessarily spin out (much) when you're hitting the gas.

All of these are on a per-craft basis. I usually start with 0.5 in both the spring and damper because that feels more "natural" to me and then adjust them as needed (heavier craft require stronger springs, etc...). I adjust traction and friction if I find real problems with the craft. Someone like @Azimech could probably write a much more in-depth tutorial.

[Alshain]

I was told by one of the developers that those gear sliders should not be touched and there is no reason to use them anymore.  This developer said he lobbied to get them moved to advanced tweakables but even his influence wasn't enough to make it happen.  I wish I could remember who it was, but it was in the 1.2 beta forum and it's gone now. (I really *think* it was Arsonide, but I'm not 100% on that)

[Azimech]

2 hours ago, regex said:

DONT YOU DARE REMOVE DETAIL!

I seriously shouldn't have to be worried about this, but suspension tweaking should remain in the game, as should any tweakables, unless that has been added back in an additional feature that the player has direct control over.

And we need even more options for tweaking. Right now the dampers have only one setting while in real life you have the much needed options bump (compress) and rebound (the opposite). Rebound is especially useful because it limits the bouncing of airplanes while landing and improves wheel-ground contact with rovers. Also missing: anti-roll bars (also called sway bars).

[HebaruSan]

I found wheel tuning to have some interesting connections to aerodynamics.

Imagine your car sliding sideways along some terrain. For it to be stable, you want its natural tendency to be to rotate the front of the car forwards and the back backwards, so you can get back to steering it normally. This can be accomplished by setting the friction values higher for the back wheels than the front, so friction with the ground tends to "pull" the back of the car backwards.

Compare to building planes. If your craft is flying sideways into the wind, you want the natural tendency to be that the air pushes the back of the craft backwards, for the same reasons as with a car. Hence you put a big vertical stabilizer as far back from the center of mass as you can.

In each case, the interaction with the medium of travel (ground vs air) is emphasized in one area and de-emphasized in another to give the craft a bias toward a safer orientation.

[Confused Scientist]

I support Autostrut and I support capitalizing... uhhh...

I support autostrut, because who hasn't had their perfect stock Saturn V recreation start bending around the third stage... slowly having the skinny parts giving in to acceleration... until it starts toppling faster... and then the capsule is inside the second stage, perfectly safe yet doomed it to a ridiculous death at S-IVB ignition.

[Azimech]

14 minutes ago, regex said:

Amazingly I can't find a tutorial around here.

Springs support the craft on the wheels, the slider determines their strength (greater being stiffer springs).

Dampers dampen the spring action so that the craft doesn't "float" on the springs, the slider determines their strength (greater being quicker dampening).

Traction control and friction control are a bit of a mystery to me, although setting the friction control lower on the back wheels can be fun. Setting friction control higher will make the craft stick to the ground better but could lead to flipping? Traction control I think has more to do with drivetrain limiting, that is they won't unnecessarily spin out (much) when you're hitting the gas.

All of these are on a per-craft basis. I usually start with 0.5 in both the spring and damper because that feels more "natural" to me and then adjust them as needed (heavier craft require stronger springs, etc...). I adjust traction and friction if I find real problems with the craft. Someone like @Azimech could probably write a much more in-depth tutorial.

I think it's pretty accurate :-) I use the same method when adjusting suspension/drivetrain.

The thing what is not known by most is that the automatic friction/traction control is the source of a huge amount of problems. The system tries to predict what the player wants, the player in return expects a certain behaviour and tries to compensate when the craft handles differently. This is fed back into the system ... etc.
None of my 90 ground vehicles on KerbalX use automatic anything (except maybe the ancient ones I haven't updated).

18 minutes ago, Alshain said:

I was told by one of the developers that those gear sliders should not be touched and there is no reason to use them anymore.  This developer said he lobbied to get them moved to advanced tweakables but even his influence wasn't enough to make it happen.  I wish I could remember who it was, but it was in the 1.2 beta forum and it's gone now. (I really *think* it was Arsonide, but I'm not 100% on that)

I'm glad it didn't happen. I wouldn't be able to give my cars these distinct characteristics, "one size fits all" cannot apply when comparing a 1968 Ford Mustang Fastback with a modern Lamborghini. I use this comparison because I used the chassis of my Mustang to build the Lambo ... yet they are completely different in every way.

17 minutes ago, HebaruSan said:

I found wheel tuning to have some interesting connections to aerodynamics.

Imagine your car sliding sideways along some terrain. For it to be stable, you want its natural tendency to be to rotate the front of the car forwards and the back backwards, so you can get back to steering it normally. This can be accomplished by setting the friction values higher for the back wheels than the front, so friction with the ground tends to "pull" the back of the car backwards.

Compare to building planes. If your craft is flying sideways into the wind, you want the natural tendency to be that the air pushes the back of the craft backwards, for the same reasons as with a car. Hence you put a big vertical stabilizer as far back from the center of mass as you can.

In each case, the interaction with the medium of travel (ground vs air) is emphasized in one area and de-emphasized in another to give the craft a bias toward a safer orientation.

Correct :-)

[AlamoVampire]

On 8/1/2017 at 7:44 PM, Wcmille said:

I don't see a downside in autostruting. It doesn't seem to affect mass, and improves the rigidity of the craft. Feels like entering a cheat code.

 

What's the intent of this feature?

 

simple. to try to calm down the "wobbly rocket syndrome" or if a picture truly is worth a thousand words, behold a station segment from around KSP 0.23 or so:

this thing has only struts available from with in the VAB/SPH part screen, and it wobbled BAD. Even with autostruts now things still wobble but not nearly as bad.

original post time 22:16:30

[JonathanPerregaux]

I've had auto-strut twist and demolish larger spacecraft to hilarious effect, so knowing how to use it effectively makes it a non-cheat to me.