Conveyor Belt

[cgredalertcc]

In 06' 1741 used actual conveyor belting to pick up the poof balls and it worked wonderfully. The only problem was that it captured the balls so well one of our team members would usually have to help the field reset crew remove them. In the off season 06'-07' we modified the conveyor system to use industrial flat rubber bands and that worked just as effectively, but allowed us to cut our robot weight by nearly 10 pounds and sped up the pick up a great deal. The pickup was driven by both FP motors with the gear box. I would highly suggest a conveyor this year simply because it takes up less space than a screw type lift and it has the capability of picking up 2 balls at a time. Whereas, in other lifts you are limited to only one ball at a time. Also an interesting observation on the bands. The rollers at each end of the conveyor were made out of 3" PVC pipe with a cap on each end and rings of larger PVC glued in place to create ridges and valleys, our intent being for the bands to ride in the valleys, but they did the exact opposite. The bands tracked to the high points and stayed there quite nicely.

[=Martin=Taylor=]

Something we have noticed about the orbit balls is that they are very springy.

If you choose to use a belt, it should be set up in such a way that it applys a good deal of force on the ball to lift it.

If your belts are too springy the balls will slip when they reach the median point between the rollers.

We've been considering using a single high tension belt, like what many teams use in their treads.



This pic , from team 45's '03 bot, is what we really want to use. Does anyone know where they got it? F.N. Sheppard, Bercoflex?

F.N. Sheppard also has these really cool "profile" timing belts that could be used as scoops to lift the balls (instead of rolling them up a channel).

[colin340]

this http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&langId=-1&catalogId=10053&productId=100388913&marketID=93& locStoreNum=1278&categoryID=525742 works well you just need to sew in to a belt and work on make it to make it track well

pm for details

[Kevin Sevcik]

Originally Posted by cgredalertcc

Also an interesting observation on the bands. The rollers at each end of the conveyor were made out of 3" PVC pipe with a cap on each end and rings of larger PVC glued in place to create ridges and valleys, our intent being for the bands to ride in the valleys, but they did the exact opposite. The bands tracked to the high points and stayed there quite nicely.

This is exactly what flat belts do, and why they can be so problematic if you're not being extremely careful with them. Flat belts will always track to the highest point of a pulley if it's at all possible for them to do so. This means that if your pulleys aren't parallel, the belt will track to the high side of the pulley. Crowning the pulley can help with this, but not if your alignment is bad enough that a "low" side of the crown is still higher than anything else. This is also why losing tension can cause belts to ride side to side or ride up onto flanges. They're all somewhat elastic, so if there's enough stretch in them to start riding up on a flange, they'll happily do so and will soon be attempting to ride on the flange itself.

I'm not saying it's not possible to be successful with them, mind. Just that it requires a certain attention to detail.

[MrForbes]

Originally Posted by cgredalertcc

I would highly suggest a conveyor this year simply because it takes up less space than a screw type lift and it has the capability of picking up 2 balls at a time. Whereas, in other lifts you are limited to only one ball at a time.

We're planning on being able to pick up two balls at once, and feed them into a screw lift. This design details are still vaporware

The screw lift does take up a lot of room, but most of that room is used to store balls, so it's not wasted.

[mathking]

We tried to make a screw lift in 2006 and it didn't work out for us. I kind of hope we can at least get a good prototype this year because I think they look really cool.

In our final 2006 design, we used a conveyor belt from flat conveyor material that was very effective. We used pvc pipe (with many "speed holes") with end caps for the rollers. We could pick up balls really well with it, and fairly easily get two balls side by side. (Unfortunately the shooting was not so good...) That said, a preliminary hand powered prototype vertical conveyor with four strands of surgical tubing worked pretty well lifting the orbit balls up 3 feet last night. One key is having a good surface opposite the conveyor to help maintain the force on the balls. The conveyor worked well enough that the render of the robot with the conveyor is still hanging on my classroom wall.

Another thing to watch out for the conveyor mangling the balls if they stay and and get pulled back down. In 2006 we would occasionally pull the balls through a 2 cm opening between the conveyor and the chassis if the hopper was full. That would probably destroy the orbit balls.

[Bruceb]

Anybody know how to go about shortening and reataching a treadmill belt??
Thanks
Bruce

[Jedward45]

There are certain materials that we have discovered to grip orbitballs extremely well..... (a little hint: bedroom would be incomplete without a dresser that can hold clothes in place....) My advice if you cant figure this out, is to bring an orbitball on a date to a hardware store an run it through any materials.

[jmarsh24]

Im looking for some urethane belting material and am trying to find a cost effective way of bonding the stuff. Anyone have any ideas?

[Dick Linn]

Does it need to be urethane, or would something like neoprene work? You might experiment with some Pliobond contact cement.

http://www.mcmaster.com/#conveyor-belts/=fxqrh

[Vikesrock]

Originally Posted by jmarsh24

Im looking for some urethane belting material and am trying to find a cost effective way of bonding the stuff. Anyone have any ideas?

Check out this thread:
http://www.chiefdelphi.com/forums/sh...light=polycord

[JesseK]

It's kinda funny how things work out.

In the last 3 weeks we've tried everything we read on these forums, and it was always one thing or another that went wrong. Finally, last night we came up with our own solution to this that hasn't been suggested on these forums. What we found left some black residue behind, so once we test 2 more materials that are coming in Thursday I'll post what we've done. I knew once I found this stuff when spelunking through TrueValue in Week 2 that we should have used it right away, but alas I'm not the only one on the team.

My tip: stay away from Lowe's and Home Depot when in a search of local hardware stores; they're too big and you'll spend way too much time looking for the right thing. Start with the mom and pop shops that are small and have everything closer together without all of the non-relevant items in between them. On top of that, usually you can touch/sample a material without opening an entire box. Then, once you have an idea of what you want, purchase the sample and test on the prototype.

[craigcd]

We have used a conveyor belt material manufactured by Intralox. It comes in multiple widths and uses a variety of sprocket diameters.

http://www.intralox.com/

[MrForbes]

Originally Posted by JesseK

My tip: stay away from Lowe's and Home Depot when in a search of local hardware stores; they're too big and you'll spend way too much time looking for the right thing. Start with the mom and pop shops that are small and have everything closer together without all of the non-relevant items in between them.

Great advice! I love looking at what the locally owned/operated Ace hardware store has on the shelves. They even got in some really nice Baltic Birch plywood, just in time for our final chassis build

[Japper]

Originally Posted by jmarsh24

Im looking for some urethane belting material and am trying to find a cost effective way of bonding the stuff. Anyone have any ideas?

We are having some great success with our conveyor which we constructed a belt from a plastic carpet runner cut down to size and riveted together so that the knubby side is out... ours works great with one bottom belt running on smooth bearing rollers (the drive roller has a pool noodle glued to it) and the other surface that the ball contacts on the top of the ball is simply a piece of a flat foam PVC panel with the anti-slip mat glued to it...

Our conveyor is driven very fast by a modified FP motor which I detialed in another post:

http://www.chiefdelphi.com/forums/sh...t=72513&page=2