Trailer mode for wheels

[pandaman]

This thought applies mainly to pulling or pushing wheeled things with a 'tractor' that is attached my a free pivoting claw.

 Simply an option that allows any steerable wheels to pivot in relation to the towing vehicle.  If find I struggle to get any towed things to follow and play nice.  

@Overland how do you do it on your trains?

[Moesly_Armlis]

The train is a complicated apparatus to engineer inside KSP.   I am new to building trains but can offer some advice.

The LY-10 small landing gear seem to work best.   Wheels on the train engine should have unlocked steering with the midsection wheels toggled inverted.  This helps to bend the vessel and initiate a turn.

The trailing car wheels should have locked steering. 

The hitch point should not be too solid and I use the docking port junior to allow for some flexibility.

Make certain that the train travels in a straight line without any control inputs.  This took a lot of tedious work and patience for my train build.  The train in the video still will drift slightly to the left side.

With the jet engines at the very front of the train it was like pulling cooked spaghetti instead of trying to push it and this improved stability at speeds above 10 m/s..

Even though it was complicated and fist shaking this train build was satisfying to drive when it all worked out. 

Also I am very hyped to try out the new wheel mechanics that are coming in the 1.1 update. 

 

Edit:

There are some very intelligent notions put forth in the response to this question:

Without that helpful advice my vehicle would have been on the scrap pile.

Edited March 18, 2016 by MoeslyArmlis

[Rocket In My Pocket]

I typically use a Stayputnik probe core as a make shift ball hitch. Then you build a "cap" to sit on top of it with wheels facing inwards towards it. Sort of a poor mans ball bearing.

Makes for a very nice and authentic trailer, that behaves as you would expect.

However I've yet to find a practical use for trailers in general.

[pandaman]

My 'target' use is for assembling surface bases from separate modules, typically that will mostly be mining and refining stuff and storage tanks etc.  My basic plan it to use a tractor rover with a claw as a tug to push and pull the modules into position which will then link to the other modules with their own claws.  It works quite well,  it's just a bit unwieldy towing them around as the wheels don't cooperate if don't get them set right.  So I figured a 'towing' setting would allow them to turn naturally as they follow the tug rather than have them locked or just doing their own thing.  

[anarkhon]

http://

 

Edited March 18, 2016 by anarkhon

[Rocket In My Pocket]

34 minutes ago, pandaman said:

My 'target' use is for assembling surface bases from separate modules, typically that will mostly be mining and refining stuff and storage tanks etc.  My basic plan it to use a tractor rover with a claw as a tug to push and pull the modules into position which will then link to the other modules with their own claws.  It works quite well,  it's just a bit unwieldy towing them around as the wheels don't cooperate if don't get them set right.  So I figured a 'towing' setting would allow them to turn naturally as they follow the tug rather than have them locked or just doing their own thing.  

For the best turning radius/responsiveness make sure you aren't building the trailer segments like cars with a wheel in each corner, if you look at a real eighteen wheeler for example the trailer has all 4 wheels as far to the back as possible, away from the pivot point. Wheels near the pivot point will fight the rotation and work against you.

Pictures of what you are proposing would be helpful.

Best of luck!

[pandaman]

10 minutes ago, Rocket In My Pocket said:

For the best turning radius/responsiveness make sure you aren't building the trailer segments like cars with a wheel in each corner, if you look at a real eighteen wheeler for example the trailer has all 4 wheels as far to the back as possible, away from the pivot point. Wheels near the pivot point will fight the rotation and work against you.

Pictures of what you are proposing would be helpful.

Best of luck!

I don't have any pics yet, so far I was just checking the idea to see if may be workable.

The concept is for each module to have its own wheels, so for stability they will need to be  spaced a bit and far enough from the centre of the to keep it stable and balanced, probably landing gear as they will survive landings better.  The most basic modules will likely be just a fuel tank with four landing gears, a claw and a probe core and battery so that I can apply the brakes.  The tug will then drag it to where it will connect to the other modules, hopefully I won't need to move them too far if my landings are accurate enough, and I'm not planning on building trains and stuff.  I just need to be able to steer them OK to get them where I need them.

[Pixel of Life]

Use a dolly:

And combine it with a semi trailer like this:

 

That way you get the maneuverability of a semi trailer and the stability of a trailer that also has wheels at the front. The hinged coupling between the trailer and the dolly allows them to rotate relative to each other. Use a rigid connection between the dolly and the tractor if you want something that's easier to reverse or make that a pivoting connection as well if you want to make it a bit more maneuverable.

[Enceos]

Meanwhile

 

[pandaman]

Wow! !  Some good stuff here , thanks to all for the responses.

After a couple of tests I did find that fixed wheels closer to the balance point of the module/trailer give me the best results.  Thanks for the hint RIMP. 

My original idea was to allow steerable wheels to 'follow' the tractor in a similar way to the 'dolly' and 'semi' idea suggested above. To get a similar type of effect without increasing complexity and, more critically,  part count into something that is largely redundant once towed into position. 

It will be interesting to see how the new wheel physics in 1.1 work for this too. Though I don't expect big changes. 

 

Edited March 19, 2016 by pandaman

[Rocket In My Pocket]

You got me thinking about trailers again, especially about making them less part intensive and more practical.

So I built a mock up hitch system that uses pretty much just the structural fuselage and the stayputnik probe core.

I'm pretty happy with it! It does require a high necked trailer to work, but that's not really an issue imo. It's also very simple compared to my previous iterations, yet functions just as well. I took some screenies of the technical mock up. (I know it's hideous...but it was just for testing. The giant fuel tanks are just counter weights, it kept wanting to pop a wheelie lol.)

Spoiler

 

[pandaman]

@Rocket In My Pocket  That's clever.  What did you use for the upright cylinder?  It looks like the structural fuselage.

[Rocket In My Pocket]

2 hours ago, pandaman said:

@Rocket In My Pocket  That's clever.  What did you use for the upright cylinder?  It looks like the structural fuselage.

Thanks!

Yup that's exactly it. At first I was against using it because of it's length, but it's one of the only parts with an actual "hole" in it that counts physics wise I discovered through trial and error. It really cuts down on the part count as prior I had to use at least 4 landing gear wheels to "encase" the probe core. (I tried decouplers but the "hole" in the middle isn't actually a "hole" as far as the game is concerned.)