Interesting solutions, but where and how shock absorbers will connect?

@Jurss Whoops, I was silly and forgot to put them in the LXF file. They connect on the 9-stud long axle with the bushings and also on the lower suspension arm. I will fix the file and picture.

 

Edit: Fixed original post!

Edited March 21, 20204 yr by TechnicRCRacer

Issue with having the suspension attached to the lower control arm instead of the upper is that when you push the suspension many times, the bottom ball join stud loosens up and starts to deteriorate due to constant pinch as the stud slips out of the hole but stays inside while compressed. 

1 minute ago, Mechbuilds said:

Issue with having the suspension attached to the lower control arm instead of the upper is that when you push the suspension many times, the bottom ball join stud loosens up and starts to deteriorate due to constant pinch as the stud slips out of the hole but stays inside while compressed. 

I put half-stud thick axle beams on either side to eliminate that issue and it seems to work fine on the physical model.

Just now, TechnicRCRacer said:

I put half-stud thick axle beams on either side to eliminate that issue and it seems to work fine on the physical model.

That works!

Hello,

back building lego after something like 35 years...  I'm a bit rusty. Please be smooth.

I would like to modify the corvette ZR1 model (42093) by adding independent suspensions.

Note that this is the buwizz version (this will have an impact for the rear axle), and that I'm totally fine to remove the fake engine.

I know that on that scale it has little no meaning having independent suspensions, but I'm OCD for that.

Let's start from the front axle.

The following constraints apply:

• Width: is 15 -17 studs (including wheels).
• It should be no more than 5 studs tall
• cross axle for steering is arriving from the bottom of the car (wheel-center-level)
• Wheels are 30.4 mm x 20 mm: I'm going for the 3 pins connection, but if not suitable for a compact solution I will stay with the original no pin holes 30.4 mm x 14mm rims.

I started from an Efferman's LDD file, but I soon stumbled into various issues:

• wheels seems not big enough for the leverages (they are too near to the ground)
• track rod is 6m that's a big issue also for a compact 

Any help is appreciated.

regards.

@mudseason There are a lot of options available if you go through the threads labelled [TC18].

 

6 hours ago, letsbuild said:

@mudseason There are a lot of options available if you go through the threads labelled [TC18].

 

Thanks a lot, [TC18] is an interesting set of threads.

The timeout-anti-bot makes quick browsing quite challenging, I fear that, despite the lockdown, I won't be able to go through them efficiently enough to get to the point in a finite time.

Unless I'm lucky e.g. someone reading my post already had similar goals and would point me to the right direction.

For the moment I proceed with my slow reading... the few posts I was able to check where either overly complex (steering + driving + suspensions) or missing a part ( - suspension).

Thanks,

KR.

 

9 hours ago, mudseason said:

the few posts I was able to check where either overly complex (steering + driving + suspensions) or missing a part ( - suspension).

That's because having steering, drive, and suspension in a 15-17 stud space is incredibly challenging and involves some clever tricks. 

As for the anti-timeout, I have no clue what that is, so I can't help you there.

That said, I'm trying to develop the same for a Skyline model I'm making. I'll be sure to post it here if I manage :)

Edited April 18, 20204 yr by letsbuild

I'm looking for two axles that have these features:

-XL drive front axle (motor mounted on axle)
-XL drive rear axle (motor mounted on axle)
-M motor steering (motor mounted on axle)
-Portal hubs + claas tyres

Heavy duty rock climbing axles.
XL motors on axles put all the weight of the moc near the tyres so it's not top heavy. 
These axles need to be joined in a central chassis so each axle has near 45 degrees of flex.

I'm already trying to figure out how @PunkTacoNYC Made the axles in hes carrot crawler moc.
It's somewhat what i'm looking for. 

 

A driven and steered suspension for the trucks wheels

Tough Axles.LXF

I just wanted to share these! 

@effermandid 90% of the work. I did some small modifications like the servo and CV joint frame. 

These axles are pretty tough and can take abuse. 
You can also take the 5x7 frame out of the middle and replace it with a H frame if you  need more connection points. 

here is a failed design of small scale front axle (partially virtual pivot steering). my intention was to make it driven, put suspension and also keep it 15stud width total with tire (from Mack anthem).

it ended as below, not so good. usable if expectations are low. There is huge slack all over the axle and turning radius is terrible. the Z arms do not turn too much so steering is not so good. main slack comes from the 3L blue thin beam. I could not replace it with a better thing (the end has to go inside the wheel to make it 15stud, otherwise it is impossible with CV and diff)

more photos in bricksafe. maybe someone can use the idea and make it better (or already done better)

 

EDIT:

Anyone made a tatra 4x4 with the iconic tatra suspension but having the axles not rest on the drive shaft? 
Like @Madoca 1977's tatra? 

The 8x8 is a massive beast but figuring out how to make it 4x4 with 4 wheel steering is quite tricky.. 
Trying to figure out a 4x4 version with dual drive shafts and the axles not resting on the driveshafts. The steering is a nightmare to figure out since when the wheels droop down, they both steer in outside and when the suspension is pressed down, both wheels steer in the middle.. 


If anybody can figure it out, please post the LDD here! 

Edited August 12, 20204 yr by Mechbuilds

Can this tatra axle be made without this part:
 (i don't have any of these)
Also smaller 20t gears in the middle since i only have 2 of those larger bewel gears. 

I'm planning on a 4x4 tatra and i like the idea of the axles not stressing the driveshaft. 
Steering is also a whole can of worms. 


All tatra mocs are mostly 8x8 and have their own special suspension and steering system. 
 

Edited August 13, 20204 yr by Mechbuilds

@Mechbuilds

You can use this

https://www.bricklink.com/v2/catalog/catalogitem.page?P=32557&ccName=4211714

But question is how wide axle do you need?

Edited August 13, 20204 yr by I_Igor

9 minutes ago, I_Igor said:

@Mechbuilds

You can use this

https://www.bricklink.com/v2/catalog/catalogitem.page?P=32557&ccName=4211714

But question is how wide axle do you need?

Those shorter parts, i only have 2 of them.. 

Really don't have the cash this month to put up a new order no matter how cheap the parts are 
As for how wide? I'd be using claas tyres. So width is pretty much what looks okay for a 4x4.. I'll build the model around the axles.. 

I'm always going for durability over looks. I like the chassis beefy and strong. 
I wonder if it's possible to have it 4 wheel steer. But since the wheels are so far apart in a 4x4 version, i'd probably have to use two servos to make it work.. That or a very very long axle and put the servo in the middle. 

16 minutes ago, Mechbuilds said:

Those shorter parts, i only have 2 of them.. 

Really don't have the cash this month to put up a new order no matter how cheap the parts are 
As for how wide? I'd be using claas tyres. So width is pretty much what looks okay for a 4x4.. I'll build the model around the axles.. 

I'm always going for durability over looks. I like the chassis beefy and strong. 
I wonder if it's possible to have it 4 wheel steer. But since the wheels are so far apart in a 4x4 version, i'd probably have to use two servos to make it work.. That or a very very long axle and put the servo in the middle. 

In this post you can perhaps find some idea for your tatra 4 x 4 project since one of my projects (on hold due to various horrible things happen to us) is a Syn-trac tractor that uses tatra axles.

Hope it could be a little bit helpful.

Here is my try: 



Obviously it needs 2 drive shafts. But everything seems to work. 
you'll just need to imagine the center be 5 studs instead of 3. 

But steering is another ballgame to make it work.. 



EDIT:
I just realized that if i use two XL driven driveshafts.. I can get tank turning on this. (by powering both axles in different direction by using the XL motors.)
Basically, you couldn't get this thing stuck anywhere. Forward and backward, tank turning, 4 wheel steering, (possibly even crab steering if a gearbox is used for the servo.) 
And ofc iconic tatra swing axle suspension.

How are you guys NOT exited? 

Edited August 13, 20204 yr by Mechbuilds

@Mechbuilds it is better to use 2 servos for multiple steering modes; there is to much slack when you use gears and not first shaft with servo. Yes it is very interesting 

On 8/13/2020 at 1:42 PM, Mechbuilds said:

Here is my try: 



Obviously it needs 2 drive shafts. But everything seems to work. 
you'll just need to imagine the center be 5 studs instead of 3. 

But steering is another ballgame to make it work.. 



EDIT:
I just realized that if i use two XL driven driveshafts.. I can get tank turning on this. (by powering both axles in different direction by using the XL motors.)
Basically, you couldn't get this thing stuck anywhere. Forward and backward, tank turning, 4 wheel steering, (possibly even crab steering if a gearbox is used for the servo.) 
And ofc iconic tatra swing axle suspension.

How are you guys NOT exited? 

I’ve got a part order coming and I am definitely gonna make something like this! Tank steering, Tatra suspension, it would be like a LEGO sherp atv.

1 hour ago, hawkwind said:

I’ve got a part order coming and I am definitely gonna make something like this! Tank steering, Tatra suspension, it would be like a LEGO sherp atv.

Awesome! I'll keep an eye on your build thread! 

Can anyone figure out a steering mechanism for this? 
The axles work for two driveshafts and they will not hang from the axle but instead be braced on the frame. This way you get less stress on the motors and a much smoother ride. 

My plan is to attach both XL motors to the two drive shafts and have a gearbox that switches from forward to backward into turn left or right tank steer. 
If i have just regular tank steer system that both drive shafts are individual then both motors will probably turn different speeds and it will steer constantly. 



EDIT:

After some testing, i've come to the conclusion. that the hinge will cause some gears clicking.. 
Also the steering ball joint needs to be at the point of the hinge.. 

I think i'll fix the gearing issue by putting a U joint at the point of the hinge. That way i'll have the iconic tatra style swing axle suspension but have none of the gear issues and no riding the drive shaft. 
But this also means that the whole build will be 2 studs wider. but i can also use a differential in the middle if i want to. 

Edited August 15, 20204 yr by Mechbuilds

@Mechbuilds

Steering could be done with help of 5L steering arms...

On 6/10/2020 at 12:52 AM, OlSom said:

A driven and steered suspension for the trucks wheels

i like this axle. I have one question though what type of mechanism will allow me to use an M motor for the steering. I would really appreciate this. And is there anybody who knows a pickup truck thread that I can follow and get tips on as well.