Team 2085 Design Questions

[jmarsh24]

Is there a certain shape we should use in our pvc guides?

For the traction control, has anybody else thought about creating a mouse set up of omni wheels to get correct turning values?

[MrForbes]

See if you can find some pictures of 842's robot Carmen, they found what looks like a good low-buck easy-to-build way of making the belt roller/pulleys, using rings of PVC pipe on a smaller ABS pipe. The belts fit between the rings.

[Greg Peshek]

As far as the groove/ separation thing, something we figured was an easy solution and are implementing right now.. is just putting the urethane belting directly onto the ungrooved PVC and using some old pneumatic tubing as guides to keep them in place.

The pneumatic tubing is just wrapped around the piece of PVC, wood screwed in at the ends and then we used CA (cyanoacrylate) glue to keep the middle of the pneumatic tubing from sliding anywhere.

It's a fairly easy and cheap solution. If you have a lot of left over urethane belting, you could always use those as guides too. Just go through the same process I described but with the belting. Of course the belting is probably more valuable than old pneumatic tubing.

-Greg

[jmarsh24]

For the sensor, which would be the most accurate and precise instrument to use, an ultra-sonic or infrared sensor?

[Bob Steele]

Originally Posted by squirrel

See if you can find some pictures of 842's robot Carmen, they found what looks like a good low-buck easy-to-build way of making the belt roller/pulleys, using rings of PVC pipe on a smaller ABS pipe. The belts fit between the rings.

We are using the same arrangement exactly... white PVC rings on Black (ABS) Styrene pipe.

We actually ran our shooter using this system at 3500 RPM last night and it worked great... although you have to be careful with alignment at this speed.
If you are collecting you won't need this speed and the ring system should work fine.

We did purchase the mini-welding kit from Fenner... for the tubing...
It is about 1/2 the cost of the fancy one from MC and works great...and I believe it is worth the price...

Here is the link... I ordered directly from Fenner and also got the belting for about 70 cents per foot instead of the 90 cents from MCarr...

http://www.fennerdrives.com/eagle_po...e_mini_kit.asp

This is the link to it... around $250 but worth it if you are using a lot of belting.

Good luck with your design!!

[=Martin=Taylor=]

Originally Posted by jmarsh24

Is there a certain shape we should use in our pvc guides?

For the traction control, has anybody else thought about creating a mouse set up of omni wheels to get correct turning values?

In '06 we just cut strips of wedge-top and pop-riveted it onto a PVC roller. The wedge top provided traction while also serving as guides.

One problem with using plastic spacers is that the objects will lose traction as they pass over that point. Might not be a problem.

Or you could use timing belts