General questions on wheel+pedal building

[metallo97]

So I have to find a way to get 1440 degrees or less. How do I find the dimensions of the pulleys? Have you got any math formula?

[tronicgr]

Maybe some videos will help you with the calculations:

https://www.youtube.com/watch?v=geVlmSja_E4
https://www.youtube.com/watch?v=uib29a4KWLQ


Thanos

[metallo97]

Do you think it's better belt and pulley or gears? I think belt and pulley because they can handle much more torque than gears...

[metallo97]

Actually found an interesting site on which you can calculate pulleys and belt lenght http://www.blocklayer.com/Pulley-Belt.aspx

[tronicgr]

Let me tell you this...

If your potentiometer has end limits and you are using gears, if you reach the end limits of the pot, you will either break the gear teeth if they are plastic or the potentiometer...

The pulley belt will most likely slip and won't damage the potentiometer, unless again you are using timing belt with "teeth" on the pulleys...

I used simple pulley with no teeth that can "slip" under lock situations, since the 10-turn potentiometer I use HAS end stop limits.
However I might use timing belt with the quadrature encoder that does not have any stop limits.


Thanos

[tronicgr]

Actually found an interesting site on which you can calculate pulleys and belt lenght http://www.blocklayer.com/Pulley-Belt.aspx

That's a good one! Great catch!!

[metallo97]

Ok, so the potentiometer has got end stoppers, so I might finish to break if I use gears... Doing simple maths calc, if my potentiometer has got a 0.6mm shaft, the pulley must be 0.6mm times the ratio you want. In my case, if I want a 1:3 ratio I do 0.6mm times 3 which is 1.8mm... Now I'm having good time finding a pulley like this lol

[metallo97]

Just watched a video on youtube where a guy made a FFB Steering Wheel with Arduino and he was changing max rotation of the wheel. Now, thinking, i can use the 10 turn potentiometer without any pulley to make it turn faster but indeed i can use arduino to stop the motion of the wheel when i reach certain degrees of angle...

[tronicgr]

Hi,

The forces on the FFB are not position, rather plain forces (torque). If you don't instruct your controller to stop the motor on the end of travel, it will keep trying to apply force.

I didn't implemented the end stops yet, but I'll need to, as it keeps running away following the forces in the game.


Thanos

[metallo97]

No, I know that forces are not positions... But because I'm using an Arduino to do the ffb stuff it will be simple to make the wheel stop turning after certain degrees...