Help with rover/planes

[Daylen]

Hi guys, I've been having some problems with my rovers and planes that keep listing left or right no matter what i do to solve this issue.

I've tried different wheels and engines (i like using jet power on Kerbin/Duna) and even if  i use the WASD to move it still lists.

This is annoying because i keep losing plane/rover missions either because they literally run off the runway before takeoff speed or flip over and blow up. 

Is there anything i can do to solve this issue??

[WanderingKid]

When it's a single design that's doing this, I usually find that it's something in the part manifest that just isn't behaving itself and I need to toss the parts and reattach them until I find the problem.

Since you're having the problem over multiple builds, this is more likely a design problem than a single build issue.  Pictures would help, craft files too.

Also, jets don't work on Duna, what mods are you running?  That can have a significant impact.

[Daylen]

1 hour ago, WanderingKid said:

When it's a single design that's doing this, I usually find that it's something in the part manifest that just isn't behaving itself and I need to toss the parts and reattach them until I find the problem.

Since you're having the problem over multiple builds, this is more likely a design problem than a single build issue.  Pictures would help, craft files too.

Also, jets don't work on Duna, what mods are you running?  That can have a significant impact.

Yeah once i looked at my game files i found out that id accidentally copied Kerbin's data over to Duna and the game righted itself once i set them back, now i have about 3 rovers on Duna which are useless lol. Thankfully i had the means to get them back to Kerbin for use in my transit operations =).

Ill get some footage and pics of my designs soon for you to see. How would i gather craft files? 

I did find out earlier though that even using wheels that can't steer the list doesn't happen as much but it really restricts how i can move about.

 

[bewing]

Generally, "listing" happens because your front wheels have too much friction, and your back wheels don't have enough. Additionally, most people put one set of wheels very near their CoM, which eliminates them from helping to maintain directional stability.

 

 

[Daylen]

7 minutes ago, bewing said:

Generally, "listing" happens because your front wheels have too much friction, and your back wheels don't have enough. Additionally, most people put one set of wheels very near their CoM, which eliminates them from helping to maintain directional stability.

 

 

Thanks for the info. I'll try the CoM thing but one of the problems is that I use the Karibou rover a lot and the wheels have specific attachment points and I'm still listing, I'll post the videos in a bit so you can see what I have to deal with

[Daylen]

Here's some quick vids showing my problems

https://youtu.be/vUHkctTzXq4

https://youtu.be/eB2jL86hJ-o

https://youtu.be/__65hZkzNe0

https://youtu.be/Z8hbUN2Vi68

https://youtu.be/TVud5G2HhcY

Apologies for loading times =/

[Val]

1 hour ago, Daylen said:

Here's some quick vids showing my problems

All the videos are marked private, so only you can view them. Set them as unlisted, then we can view them. They'll not be found when searching on youtube.

[Daylen]

Should be ok now. I forgot about my settings lol

[Val]

In the first video, that main landing gear is way too far back. When you have steering on the front wheel, then the main landing gear should be right behind CoM for best stability.

In the other videos the small amount of veering left or right seems about right for the speeds and wheel layouts.

[Daylen]

Ok thanks, I've been able to fly them once their off the runway it's just the initial list is annoying.

I'm not overly fussed with rovers considering the fact that I only use them for short journeys.

Thanks for the help =)

Edited October 21, 2016 by Daylen
Autocorrect........>=/

[Val]

With KSPs current wheel physics, I don't think it's possible to create the self-stabilizing geometries that real world cars have.

[Daylen]

I did notice a difference with the 1.2 release. I've never really had this problem before and I've clocked over 300 hours in game

[bewing]

23 minutes ago, Daylen said:

Should be ok now. I forgot about my settings lol

OK, several points:

1) When your craft is spawned, it is not guaranteed to be pointing straight down the runway -- there is always the chance that you may have to aim it a little before you launch.

2) Terrain in KSP is not flat, including the runway. Every time you hit a bump or dip, that will cause your craft to try to veer.

3) When you just use the edtior to attach wheels the normal way, they will be close to being straight, but they will not be perfectly straight. Non-straight wheels will always cause your craft to veer. To get your wheels perfectly straight you need to click the F key to go into "Absolute Rotation Mode" and then adjust them one click back and then forward.

4) Overloading your wheels (that first plane was way too heavy for those baby wheels! 7 tons max with a tricycle using them) will cause the wheel suspensions to flex and the wheels not to roll straight.

5) The stuff you are showing is exactly what SAS Stability mode is for. Vibrations and fluctuations will prevent any craft from going perfectly straight. Turn on SAS, and it will automatically do the tiny steering corrections needed to maintain a good heading.

-- So really, your videos didn't look bad at all to me. Most of your craft made it a third of the way down the runway with no steering corrections at all. If you turned on SAS, then probably every single one of them would have rolled straight down the middle of the runway.

 

 

 

[Daylen]

26 minutes ago, bewing said:

OK, several points:

1) When your craft is spawned, it is not guaranteed to be pointing straight down the runway -- there is always the chance that you may have to aim it a little before you launch.

2) Terrain in KSP is not flat, including the runway. Every time you hit a bump or dip, that will cause your craft to try to veer.

3) When you just use the edtior to attach wheels the normal way, they will be close to being straight, but they will not be perfectly straight. Non-straight wheels will always cause your craft to veer. To get your wheels perfectly straight you need to click the F key to go into "Absolute Rotation Mode" and then adjust them one click back and then forward.

4) Overloading your wheels (that first plane was way too heavy for those baby wheels! 7 tons max with a tricycle using them) will cause the wheel suspensions to flex and the wheels not to roll straight.

5) The stuff you are showing is exactly what SAS Stability mode is for. Vibrations and fluctuations will prevent any craft from going perfectly straight. Turn on SAS, and it will automatically do the tiny steering corrections needed to maintain a good heading.

-- So really, your videos didn't look bad at all to me. Most of your craft made it a third of the way down the runway with no steering corrections at all. If you turned on SAS, then probably every single one of them would have rolled straight down the middle of the runway.

 

 

 

That is really good advice. I wasn't even thinking about the wheels I was using, its my career game so I don't have better wheels yet.

I also had no idea about the Absolute Rotation Mode so that will really help me out, thank you =)

[bewing]

Sometimes the better wheels show up on one of the contracts. Just avoid completing the contract, and you get to keep the wheels.

[WanderingKid]

4 hours ago, Daylen said:

Here's some quick vids showing my problems

https://youtu.be/vUHkctTzXq4

https://youtu.be/eB2jL86hJ-o

https://youtu.be/__65hZkzNe0

https://youtu.be/Z8hbUN2Vi68

https://youtu.be/TVud5G2HhcY

Apologies for loading times =/

I'll do what I can here, but I want to say that bewing pretty much nailed it.  The first landing gear is also REALLY weird.  It kind of does what it wants unless you beat it into submission.

1) SAS.  Use it or fall off the runway.  There are a thousand rounding translations (note: NOT ERRORS) that modify tiny things in KSP that will translate into a massive change over time.  Movie 1: You're off the runway at 90 m/s.  You should be airborne already.

2) Movie 2: That's damned near straight without SAS.

3) Nice toy.  No.  You have all the stability of a ruler set on its edge.  I'm surprised that didn't run into the radar array.

4) Few things here.  First, it lists right, not left, so that's an indicator that you don't have a systematic issue.  Second, you're using an engine against wheels.  While rover wheels aren't the same as the horrid issues that I've had plague me with the opening landing gear, they're still twitchy.  I'm curious to see what they'd do if you DON'T use an engine against them and used them normally.

5) You're not straight to start.  Look at the first 10 seconds on the runway.  You're already aimed off kilter.

This might help; the runway isn't flat.  It curves to the planet's curve.  Nature of the beast.  Due to the curve the expectations must change, which means you must adjust slightly when necessary.  Additionally you can't expect your flying Kraken to land on the runway just so.  It'd be nice if you could but my personal experience says there's always a little bit of adjustment necessary.  On larger craft the mass usually can overtake the minor bumps and weirdness that occurs on the runway, but smaller craft will always need a nudge.

Due to *my experiences* (please note, YMMV) I recommend the following for runway use: Start at 1/3 throttle, and wait until 20-30 k/s to figure out if you're aimed right.  Adjust with caps lock on (minor adjustments) to the proper direction.  Kick it up to full throttle, and do what you planned to do.  My personal opinion is if you didn't try to use jets on your rovers you'd be okay, but that's experience from non-Kerbin usage.

[Daylen]

Awesome advice guys =). I have noticed a huge difference in my gameplay now I've used your advice.

I have re-tweaked the SAS settings in the config files (I changed it to make my planned YouTube channel harder and forgot) and I've had next to no listing with my planes (the only reason I didn't set it up in the videos was to show the extreme listing) however it's not much different in rovers.

The only reason I like to use jet propulsion is because every other type (including Electric) is far too costly in my eyes and there's no petrol/gasoline resources in game, which would be epic and I would literally pay a modder to implement it into the game as a secondary rover propulsion. If I could mod I would do it myself because (in my eyes) you could get a much longer run time with a combustion engine and you could use it to generate a vast amount of early electricity without needing a ridiculous amount of batteries and relying on the sunlight.

I love that Interstellar Extended allows for beamed power once you unlock the correct R+D nodes but early game it is difficult to get stuff done without having to rely on electric power.

Moving on, I always try out wacky ideas in game, like my old Mastodon Transit Solver when I first figured out orbital mechanics (basically it was a 750mX500mX1km block that had it's orbit close to the sun and Eeloo) and my runway-sized Environment Pooper Scooper which never took off lol (I tried to scoop every type of atmospheric resource at once and gather an OP amount)

[Val]

21 minutes ago, Daylen said:

The only reason I like to use jet propulsion is because every other type (including Electric) is far too costly in my eyes

How is electric too costly? Mass?

 

22 minutes ago, Daylen said:

There's no petrol/gasoline resources in game.

Using a fuel cell is a pretty good analog in my opinion. And it can be refueled with an ISRU.

[Daylen]

1 hour ago, Val said:

How is electric too costly? Mass?

 

Using a fuel cell is a pretty good analog in my opinion. And it can be refueled with an ISRU.

Pretty much yeah, that and the low electric production at first irritates me. In some cases I've had to cover the entire outer skin of my designs with solar panels and I still run out of power. Although I did forgot about the fuel cell lol. 

[Val]

There's also the PB-NUK RTG 

 

Speaking of Jet powered Rovers, I made this one back in August.

 

Edited October 21, 2016 by Val
Link fubar

[Daylen]

Nice rover lol. Yeah I love those little guys but when your playing a career it takes a fair while to unlock them, hence my frustration XD