Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: ibot on May 16, 2010, 09:50:53 AM

Title: how to connect one servo motor to two wheels ?
Post by: ibot on May 16, 2010, 09:50:53 AM
Hi,

So far I am mounting a servo to a wheel .. But, wondering if it is possible to use one servo motor .. to connect to two wheels? So, when the servo mount rotates .. two wheels will rotate..

0----0

0----0

Imagine the above dia as wheels :) .. so, I want to connect two wheels in such a way .. but, use a single servo motor to rotate them. Please let me know how to do this.

Greatly appreciate any help !! Thanks !!
Title: Re: how to connect one servo motor to two wheels ?
Post by: Razor Concepts on May 16, 2010, 10:15:11 AM
Direct drive axle
http://buggies.builtforfun.co.uk/Howtoos/Images/Single-Stage-Drive.jpg (http://buggies.builtforfun.co.uk/Howtoos/Images/Single-Stage-Drive.jpg)
Title: Re: how to connect one servo motor to two wheels ?
Post by: ibot on May 16, 2010, 11:18:14 AM
Thanks for the link. It really looks great !!

I googled it and did not found any though .. wondering if I can find this as off-the-shelf product :) ..

Thanks !!
Title: Re: how to connect one servo motor to two wheels ?
Post by: Razor Concepts on May 16, 2010, 12:22:40 PM
Get two gears, put one on the axle, one on the servo, and you are done?

You can't buy this as an off-the-shelf product.

If you need help constructing this, give us more information on the specifications of everything you need
Title: Re: how to connect one servo motor to two wheels ?
Post by: ibot on May 16, 2010, 10:11:19 PM
bot design: [O= omni wheels]
 ---- O ----
|              |
O              O
| ___O____|

-> I am planning to use omni wheels. The bore diameter of the wheel is 3/8th of an inch. So, my axle diameter will be 3/8th inch dia too ..
-> length between two wheels is 12 inch on one side and 8 inch approx on other side
-> actually, I used HS311 and HS422 earlier. I don't know how to tell its capacity ... but, HS311 would be perfect for this one too .. so, I really like to use 1:1 gear ratio with this servo if possible ..

Questions:
1. wondering how to fix the gear on a axle ? I mean .. how can we make it not to move freely to left/right on axle.
2. My servo shaft should use a gear as a mount ? and that gear will be attached to the other gear on axle? am I right?
3. currently I have 4 wheels of same length. If you see the above design, it needs 2 axles. But, those 2 axles will have a collision :) as all the wheels are of same length. wondering, if there is a way to address this problem?

Greatly appreciate your help !! Please let me know if you have any questions or need more information.
Title: Re: how to connect one servo motor to two wheels ?
Post by: Razor Concepts on May 16, 2010, 10:15:05 PM
It would be much easier to put one servo on each wheel to avoid the axle conflict.

Go to www.servocity.com (http://www.servocity.com) for axles/hubs/mounts etc etc. Kind of expensive but very high quality.