Which suspension type should I use ?

[Storext]

(sorry for my bad english) I'm thinking which suspension type should I use for my race car. I'm doing it outta LEGO Mindstorms (NXT/EV3). It's suposed to be RWD (with differencial) car for racing on flat surface. But on the the track the is one jump - it has 15 cm (or 5.9 inch). And I need suspension that is going to be light, kinda robust (it has to survive fall from 15 cm (5.9 inch) and also simple. I was using multilink suspension in the back and something like McPherson in the front, but it didn't worked as i wanted. So I'm thinking about using still multilink in the back, but double wishbone suspension in the front. (I'm using soft springs because car weights 850 g (or 1.87 lbs)).

What do you thing is it allright or should I change it, or are there some bad sites of this two types of suspension ?   

[TheMindGarage]

26 minutes ago, Storext said:

(sorry for my bad english) I'm thinking which suspension type should I use for my race car. I'm doing it outta LEGO Mindstorms (NXT/EV3). It's suposed to be RWD (with differencial) car for racing on flat surface. But on the the track the is one jump - it has 15 cm (or 5.9 inch). And I need suspension that is going to be light, kinda robust (it has to survive fall from 15 cm (5.9 inch) and also simple. I was using multilink suspension in the back and something like McPherson in the front, but it didn't worked as i wanted. So I'm thinking about using still multilink in the back, but double wishbone suspension in the front. (I'm using soft springs because car weights 850 g (or 1.87 lbs)).

What do you thing is it allright or should I change it, or are there some bad sites of this two types of suspension ?   

Unless you build your suspension extremely well, it is probably more likely to break than a vehicle with no suspension whatsoever. If you only need to absorb shock (ie no side-to-side movement), you might want to consider a simple hinge or a sturdy floating axle.

[Storext]

10 minutes ago, TheMindGarage said:

Unless you build your suspension extremely well, it is probably more likely to break than a vehicle with no suspension whatsoever. If you only need to absorb shock (ie no side-to-side movement), you might want to consider a simple hinge or a sturdy floating axle.

I was also thinking about that, but on the track there are lot of turns so the car is going to have little side to side movement (i want to use sabilizer (or sway bar) in it so it is not going to roll over)

Edited January 28, 2018 by Storext

[Mechbuilds]

Post an image of your project.

[Storext]

26 minutes ago, Mechbuilds said:

Post an image of your project.

I would very like to ,but i don't have any photos of it and that car is now, well .... at school (because I'm doing it for one competiotion in the name of my school) but at Monday afternoon I will around 4:00PM (GMT+1)

 

Edited January 28, 2018 by Storext

[Vectormatic]

if this is a flat track with just one straight jump, there is no need for suspension, esp on a 1kg car, no need for complicated axles and sway bars, just use rigid axles and keep the weight as low to the ground as you can, if you need to absorb the bump from the jump, id suggest large sidewall tires, generally speaking those will be just as effective as lego springs, which are really hard to set up properly

[Storext]

Ok, thank you very much for your early reply and all your tips. I realy appreciate it. 

[Jurss]

Maybe some suspension would be still good, but, to keep it good in corners, maybe make it really simple, like on 42075. Make some experiments, and try to adjust it just for that jump.

[TheNextLegoDesinger]

i would opt for a solid front axle and an live rear axle, this way you have some suspention, and it will be pretty sturdy.

this one has that type of rear axle i'm talking about. i don't know if your school has these parts. otherwise you could use a hinge system for your suspention

 

[Storext]

I'm afraid we don't have these parts. Because we only have NXT and EV3 (we don't have PF) and also we only have older differential , but I guess I can do that work even without those parts. And that baja truck and 42075 rear axles are pretty similar (but i probably take more inspiration from 42075 set, because it looks lighter and more simple). Thank you very much guys :)

Edited January 29, 2018 by Storext

[andythenorth]

If the track is flat, just do two big swingarms on the rear to a beam axle, and one or two springs.

It will only move up and down parallel to the chassis, no twist, but will take out shock loads.

I just built one of my kids a PF buggy this way.

Edited January 29, 2018 by andythenorth

[Storext]

On 28. 1. 2018 at 6:13 PM, Mechbuilds said:

Post an image of your project.

Now I randomly found few pictures of that car in my phone , so I'm going to upload it here (but I took that photo for presentation of RPM meter that I made) so it's not ideal
(those motors in the front are just for stopping car from moving forward)

Here is that photo : https://imgur.com/a/AbR9D 

Yes, and also it is pretty old photo because it was prototype 1 (just for testing spring hardness and RPMs of wheels motors etc.

Edited January 29, 2018 by Storext