[HELP] Articulated Steering 8x8 Rolligon

[Doc_Brown]

Hi Everyone

I have been trying to find info on the Rolligon, but not having much luck at all.

My main query is to find out how the steering works in an 8x8 version.

As you can see from the very small pics below obviously turns in the middle but does it pivot up and down to allow for hills/ terrain?

Does it still "roll" as well?

Any info or advice would be great, Thanks!

[Edwin Korstanje]

it looks like skidder steering.

[jorgeopesi]

Do you know this great page?, http://www.unusuallocomotion.com/pages/more-documentation/18-8x8-wheeled-and-more-articulated-vehicles-heavy.html

[Doc_Brown]

it looks like skidder steering.

I don't think it is skid steer cos the 4x4 are not , and if you look at this pic below you can see a pivot in the center. This is a model tho, so hopefully it is accurate. hehe.

Do you know this great page?, http://www.unusuallo...cles-heavy.html

Sweet! I was looking for that!

Check out this pic, deff shows it twisting, but still not sure if it pivots up and down.

Yeh I think it does pivot up and down, WOW that is going to be a challenge to make for sure! I'm excited!

Edited August 2, 2014 by Doc_Brown

[jorgeopesi]

It looks like I discovered my secret , take care of it .

[Zerobricks]

Ball joint will be highly usefull here

[Doc_Brown]

Ball joint will be highly usefull here

could not agree more! This is what I have come up with, its very strong and gives reasonable turning and pivoting. Just hope those lil LA's are up for the task!

[Zerobricks]

could not agree more! This is what I have come up with, its very strong and gives reasonable turning and pivoting. Just hope those lil LA's are up for the task!

If they are not up to it you can always use big ones! And I think you will have to use big ones...

[Doc_Brown]

If they are not up to it you can always use big ones! And I think you will have to use big ones...

I did think of that, but they take up soo much more room and they are metal, with a chance of rust as this will be going swimming!

Fingers crossed this way will work, hehe.

[Zerobricks]

I did think of that, but they take up soo much more room and they are metal, with a chance of rust as this will be going swimming!

Fingers crossed this way will work, hehe.

If it doesnt you can always use steering racks and worm gears

[andythenorth]

Hi Doc,

I have Rolligon info, but am heading out right now Will post later.

Meanwhile:

https://www.flickr.c...tream/lightbox/

Mine pulled a turntable apart

Also video...

https://www.flickr.c...in/photostream/

Edited August 2, 2014 by andythenorth

[2winged]

You could try something like the joint found at the following link, then again it probably won't work for you as it does not hinge vertically. http://www.hamm.eu/e...3k-knickgelenk/

Edited August 3, 2014 by 2winged

[andythenorth]

There are three Rolligon 8x8 models.

As best as I can tell:

The 8860 has three degrees of movement: roll, pivot (steer), vertical pivot.

There's an image of a yellow one on the NOV site, you can see the large roll joint, and the axis for the vertical pivot (directly under where the rear deck starts).

NP Model 8860 built for use in Mexico(1).jpg

You can also see similar structure on the 101060 5-axle unit here, plus what looks a large arch for routing hydraulic lines, suggesting a high range of articulation. NP 101060 N. Houston pipeline job.jpg

I never figured out if the 8860 has suspension, it may just rely on the flexing of the tyres. Walking beams would slop around with a vertical pivot, leaving the unit sagging in the middle. There might be leaf springs in there though.

Can't find a bigger original of this 101060, but you can see clearly how the vertical pivot works

http://www.unusuallo...pg?fx=r_250_250

The Brute and Super Brute specs say roll and pivot. I think that means 'steer' rather than vertical pivot.

There are some pretty good specs and images in pdf linked below. The Brute has front and rear walking beams, which makes me doubt a vertical pivot, and I don't see any structure for vertical pivot in any of the images I found.

http://s4.e-monsite....nd-more-pdf.pdf

Hope that's useful I have some higher res images saved locally, but can't post here, copyright issues.

For the model:

Looks like you're building similar size to mine. Prove me wrong, but I don't think the mini-LAs will stand up to it. I also had to move both LAs to the same side. Keeping them in sync on opposite sides is really hard, and you also have to get perfect geometry otherwise one will bind.

Mine's a Super Brute, so no vertical pivot, but does include walking beams, motors directly on the axle. I think the 8860 is probably a more straightforward build, and might be more fun to play with (I think it will perform better).

[Zerobricks]

The new tumbler whels would be ideal for such a model.

[Doc_Brown]

There are three Rolligon 8x8 models.

Wow thank you so much for all that useful information, I really appreciate it!

Sorry to see your one break in half, must have been pushing it really hard!.

So looks like im making the 8860 with larger wheels and cab.

Just tested the chassis at. 1.3kg, and 1 L motor can turn it geared 3:1. hopefully when fully finished it won't weigh more than 1.7kg.

[Bricktrain]

more info here http://www.eurobricks.com/forum/index.php?showtopic=95488

[Bzroom]

I think one of these things could drive over you and it would tickle more than hurt. 3psi! Atmospheric pressure is 14psi.

[Zerobricks]

Are they by any chance also amphibious?

[andythenorth]

The 8860 is amphibious up to 4.5t payload.

The Brute is amphibious up to 6t payload.

The Super Brute spec doesn't mention amphibious.

I won't be trying my MOC in water, it's got £££ of L motors in, more than I can afford to destroy

Rolligons are boss, but so are Foremost, especially the Commander http://www.foremost....oducts/vehicles

Edited August 4, 2014 by andythenorth

[Technyk32231]

Instead of linear actuators, if you aren't a purist, you could use Efferman's custom "worm gear counterpart".

[Doc_Brown]

Are they by any chance also amphibious?

Yes most are from the vids I have seen, and hopefully mine will be too. I'm aiming for 1.6 -1.7kg and will deff float nicely at that weight.. Minimum cab design with flex in red is the only way.

Instead of linear actuators, if you aren't a purist, you could use Efferman's custom "worm gear counterpart".

I won't be purchasing anymore printed custom parts as they are too weak, inaccurate and dusty taking ages to clean up.

Thanks for all the feedback and info guys, especially andythenorth! Cheers.

[andythenorth]

Will be interested to see it floating

Mine is at 1.9KG just for 8x power puller wheels and L motors. Built for pulling power.

[gti180]

i think the front chassis skid steers and the rear is driven via a diff. ive also trucks similar to this have two front steered axles as well as articulation

[andythenorth]

Nah Specs imply diffs front and rear on Rolligons. Steering brakes or steering clutches are just more to go wrong in the mud. Might be wrong, but none of the docs mention them.

[Doc_Brown]

Yeah I think skid steer would be a bit much for them to handle.

Hopefully tmr I will get a chance to finish this up. :)

Will be interested to see it floating

Mine is at 1.9KG just for 8x power puller wheels and L motors. Built for pulling power.

I'm looking forward to seeing it float too! Wow that sure is heavy. Still working on the design?