Steering mechanism for tight wheel wells?

[hamster_lego]

Just had a look at a video of the Unimog. The turning radius is even worse than what I thought after reading your comment. It's actually so bad, it's hard to belive.

uh...http://www.lpepower.com/content/lpepower-show-episode-8

[Lira_Bricks]

Sorry for necroing this old thread, but I need steering for my cars and buses and didn't feel like creating a copy of this thread :P

I already had steering in https://www.eurobricks.com/forum/index.php?/forums/topic/181558-moc-5-seat-7-studs-wide-car-with-steering/, but that kind of steering takes up to much space, as was already mentioned multiple times in this topic...

I came up with this modification of the steering of City Hunter, making it smaller in width:

It seems to work fine when testing, but I have not used it in a MOC yet. Maybe the connection between the white liftarms and the red bars is not strong enough for that.

[MinusAndy]

On 6/16/2011 at 12:10 AM, Superkalle said:

A lot of good ideas. Thanks a lot guys! I'll go ahead a and try some of these out.

I wonder why not TLG uses any of these methods, instead of creating such ugly, oversized wheel wells, such as this one:

http://www.brickset.com/detail/?Set=4896-1

It’s cos kids don’t care!

[SaperPL]

Here are my approaches to this problem. There were better constructions on the previous page with gifs, but depending on your model construction this may be useful as well:

Thanks guys for digging up this topic though, the previous page is pure gold.

[msk6003]

Technic never made virtual pivot steering but 76139 batmobile in superheros is first lego set which use virtual pivot steering.

[Lira_Bricks]

12 hours ago, SaperPL said:

Here are my approaches to this problem. There were better constructions on the previous page with gifs, but depending on your model construction this may be useful as well:

That steering is so brilliant, thanks for sharing!

[fulk]

12 hours ago, SaperPL said:

Here are my approaches to this problem. There were better constructions on the previous page with gifs, but depending on your model construction this may be useful as well:

Thanks guys for digging up this topic though, the previous page is pure gold.

Great solution !
 

[SaperPL]

On 12/15/2020 at 12:03 PM, Lira_Bricks said:

That steering is so brilliant, thanks for sharing!

 

On 12/15/2020 at 12:25 PM, fulk said:

Great solution !

I'm assuming you are talking about the forklift steering? Because the small scale one is just variation of what is there on the previous page, just with slightly different approach.

There was a guy that did this kind of forklift steering in a land rover B/C-model, but he had the drive on those wheels and he made it more real like because of that. In my forklift it's probably impossible to put drive in this specific configuration of steering, but take a look at my different prototype:

https://imgur.com/a/y6Vlkp8

The project was a mild failure because the PF servo is not a real servo in context of returning to centre under load and having multiple specific angles of turn. But I'll get back to this project at some point with PoweredUP motors as these are actually working like real servos.

[Lira_Bricks]

Actually I was talking about your first steering ^^. It works better for me.

I did remove the black 36-tooth gear and the black 12-tooth gear, as the movement from the other gear is enough to get the steering to work :)

[SaperPL]

9 minutes ago, Lira_Bricks said:

I did remove the black 36-tooth gear and the black 12-tooth gear, as the movement from the other gear is enough to get the steering to work :)

Well, yes, but not fully. The gears are there because without them the mechanism gets stuck at the ends of the range and going back needs increased force and thus it's not linear motion to get back to center from fully turning wheels. That's the reasoning.

[Lira_Bricks]

Just now, SaperPL said:

Well, yes, but not fully. The gears are there because without them the mechanism gets stuck at the ends of the range and going back needs increased force and thus it's not linear motion to get back to center from fully turning wheels. That's the reasoning.

Ah, I had that problem too with the 4 gears. I solved it by putting a pin with friction between the steering so it could not go all the way.

[Lira_Bricks]

So I figured out a way that works for me:

Spoiler

The steering is not completely smooth, but it becomes smooth once the brown + is "fixed" by the floor of the bus, for example with a https://www.bricklink.com/v2/catalog/catalogitem.page?P=3176&name=Plate, Modified 3 x 2 with Hole&category=[Plate, Modified]#T=C

[Lira_Bricks]

Here I am again. The solution in my previous post was to high, since the gears needed space. I figured out a different way, without any gears. It works by moving the yellowy orange disc back and forth*.

There is a lot of backlash when driving in a straight line, but that is solved by the fact that when pushing, the vehicle wants to go in a straight line and corrects the wheels :)

Spoiler

Driving in a straight line:

Turning to the left:

Turning to the right:

The bottom side:

The solution is a body with a height equal to that of a "Technic, Pin Connector Round 2L"!

Before I made this version I did not know about "Technic, Axle and Pin Connector Toggle Joint Smooth" and "Technic, Liftarm 1 x 5 Thin with Axle Holes on Ends". Without those two elements this would not be possible :P Those pieces are also relatively old, so quite strange I did not know about them ^^

Hopefully this is useful for someone else too :D

 

* it might not be clear in the pictures, since you only need to move it a little bit for the steering to work.

 

Edit: I figured out a better way of steering, and now there is no backlash:

Spoiler

The build itself is quite messy, but I decided to update this post before making a better construction.

Edited February 19, 2021 by Lira_Bricks
Better version of steering

[jbohac]

My steering solution for a 4s wide vehicle.
https://youtu.be/hJwfH5iIoy0?t=130
 

 

[roeltheworld]

I got a McLaren Elva speed champions set the other day, and I wanted to make it more interesting by adding steering.

Turns out this thread exists, so I want to show you my latest update.

So this is the rear, in my opinion the best looking part of the set:

It's an 8-stud wide chassis, and the wheel arches are as tight as a colorful metaphor.

So here's the front I got so far, though I've got ideas to improve the look of the wheel arches by using the little 2x2 wing plates.

Obviously it won't look like an Elva anymore, but it's got a little muscle car shape to it:

Here's the bottom:

The steering radius is quite good:

The 6x1 flat liftarm turns 10 degrees

 

One issue here is that I needed a part that Lego does not have (I think) but Cada does:

So, I don't have a solution yet for getting the same kind of compactness without using this part. In my Studio model I've used another part in it's place that shows the movement of the wheels.

 

The next problem is that the HoG cog turns the wrong way, and it's right where I want to put a windshield.

So I've designed a solution to fix both issues.

This file compares two versions, and shows the degree of movement of the wheels.

https://www.mediafire.com/file/el5w0t81els0lmz/system_steering_1.io/file

Here is the file with only the one chassis design:

https://www.mediafire.com/file/a9s4zdfj3iyvkri/system_steering_2.io/file

 

I'll try to get some kind of muscle car done in the next few weeks or so. 

Edited February 3, 2022 by roeltheworld
trying to show pictures in links...

[2GodBDGlory]

Nice and compact! I'm not sure if you'd have quite enough ground clearance, but in order to get rid of that CADA part you could try replacing it with a 32184, and then replace the 1/2 and 3/4 pins with the 22484 bar with towball jammed in as far as possible.

[stevendejong]

Hi everyone, I'm reviving an old topic because I think I might have something to add. :)

I've designed an operable virtual pivot steering mechanism for 6-stud cars. I'm attaching an image of the mechanism inside a bus.

Notable (I think) is:

1. The mechanism does not rely on tolerances in Technic. The parallellogram slides along an axle.
2. The wheels are not rotating exactly around their own z-axis, but the rotation point is close enough. In theory, they could rotate within the gap of a Lego mudguard such as 35789. Unfortunately, pretty Lego mudguards have a wall on the inside, preventing the wheel from rotating inward and blocking the possibility to add a mechanism there. This is why the bus has brick-built mudguards.

Full gallery and annotated close-ups:
https://bricksafe.com/pages/stevendejong/virtual-pivot-steering-for-6-stud-vehicles

My Rebrickable page:
https://rebrickable.com/users/stevendejong/mocs/

[Jurss]

1 hour ago, stevendejong said:

I've designed an operable virtual pivot steering mechanism for 6-stud cars.

Interesting idea, but have You built it for real?

[Zerobricks]

13 minutes ago, Jurss said:

Interesting idea, but have You built it for real?

Exactly, those connectors held by half a stud will instantly fall out due to the rounded edges. BUT you can use 41678  instead of half bushes and it should stay together.

Edited June 29, 2023 by Zerobricks

[gyenesvi]

36 minutes ago, Zerobricks said:

Exactly, those connectors held by half a stud will instantly fall out due to the rounded edges. BUT you can use 41678  instead of half bushes and it should stay together.

Same thought here of them falling apart, though they might work for a while in a light-weight vehicle on flat surface when the parts are new.. But I wonder how you would use 41678 here? The only reasonable space I see putting them is upwards, otherwise they'd block the mechanism, but the floor of the bus is there, not leaving enough space upwards either.

BTW, interesting idea for a small build like that! I guess the steering axle becomes reversed, that's why a lever is used instead of a gear?

[stevendejong]

Thanks for the incredibly knowledgeable feedback. Unfortunately I haven't been able to try the mechanism yet.

Yes, those connectors are a potential issue. My problem with Technic is often that I know what I want to do, but the pieces are simply not available. :) That also explains why I am using the yellow ball connector; it's the only piece with two perpendicular axis holes. The suggestion to use 41678 is useful, but we end up with two pin holes for our rotation point instead of one. If anyone has a solution, please don't hold back!

And yes, the steering direction is reversed wrt the steering axle. There are arrows under the lever to indicate the direction the vehicle will travel if you move the lever towards the arrow.

[vascolp]

Cool idea. I am also afraid it might not be strong enough. But if you use two sliding axles instead of one, and this part, it will hold. You will probably have to use two of this  to attach the sliding axles. Than you have to brace it very well...

Good luck! 

 

[stevendejong]

Quote

Cool idea. I am also afraid it might not be strong enough. But if you use two sliding axles instead of one, and this part, it will hold. You will probably have to use two of this  to attach the sliding axles. Than you have to brace it very well...

Thanks for the feedback and suggestion. I don't think I understand how to attach the steering axle if I use two sliding axles. Also, the parallellogram needs to rotate with respect to the sliding axle.

Would you be able to provide a screenshot / render?

Edited June 30, 2023 by stevendejong

[stevendejong]

A potential solution for a stronger build would be to make the parallellogram 5 studs instead of 4 and to attach thinner wheels. This has some disadvantages though.

1. Reduced steering angle, approximately 15 degrees instead of 20. See red lines.
2. Wheels are not turning around their own z-axis. They don't touch the chassis or mudguards, but steering looks less aesthetically pleasing. See green intersection.
3. Those thin wheels and tires are less cool. :)

 

Edited June 30, 2023 by stevendejong

[SaperPL]

36 minutes ago, stevendejong said:

A potential solution for a stronger build would be to make the parallellogram 5 studs instead of 4 and to attach thinner wheels. This has some disadvantages though.

1. Reduced steering angle, approximately 15 degrees instead of 20. See red lines.
2. Wheels are not turning around their own z-axis. They don't touch the chassis or mudguards, but steering looks less aesthetically pleasing. See green intersection.
3. Those thin wheels and tires are less cool. :)

 

I tried doing exactly this, but I wanted to use the same size tyres as the ones at the back of a 6 stud wide semi tractor that I was building and couldn't get matching size and style tires for the front.

It's either Technic parts not being there for small mechanism or the not having slim tires for specific scale. Which tyres are those btw?

Edited June 30, 2023 by SaperPL