Vaccuum gripper

Technical Technical Discussion
1

I haven’t been able to find anything on Chief Delphi about this. Any thoughts on using a vaccuum gripper to pick up the game pieces?

2

My team briefly considered the possibility, but it seems like it would be expensive to build your own.
furthermore, it would be effective for holding the tubes, but it seems like it would be difficult to position them the right way. i don’t know. maybe not so difficult.

how were you planning on building it? would it hold the tube from the top or the sides?

3

Try searching for “vacuum” (one c).

You’ll get lots of hits.

**

4

Thanks.

5

I can only hope that this is a joke.

6

Agreed, Vacuum may not be a good choice. Test it before committing to it.

7

I’ll agree with Don test before you commit, but we used vacuums on last years robot. They were made from 2.5 gallon shop vacs from Home Depot.

http://www.team228.org/gallery/124/slideshow/img_38f6a-38f6a.jpg](http://www.team228.org/media/pictures/view/6080)

They cost about $25 and we powered them with a FP motor. It was a pretty simple modification. FIRST cut away everything extra except the impeller housing and a little of the flange material for mounting surfaces. The brush mount for the stock ac motor was a perfect fit for the FP motor mount. Then you just needed to turn a shaft on the lathe to mate the FP motor shaft to the vacuum impeller. Here’s a picture of the finished modifications. The entire mechanism with hose, mounting hardware, and our final COTS suction cup was under 2 pounds.

http://www.team228.org/gallery/124/slideshow/img_4ec99-cfcd2.jpg](http://www.team228.org/media/pictures/view/6084)

I thought this might help if you do want to test vacuum grippers.

8

Nice.

Do you have any data for that design, such as current draw with and without a piece being held?

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9

Vacuum grippers are really good picking up objects that have a readily oriented flat surface, and for spherical objects. The biggest challenges you will face with this year’s game pieces are orienting the suction cup to get a seal, sealing, and achieving sufficient holding force not to drop them. The holding force is proportional to two things:

  1. The pressure differential between the environment (atmosphere) and inside the suction cup
  2. The area inside the suction cup.

This years game pieces do not lend themselves well to large suction cup area, so you will have to rely on high vacuum. You can’t achieve much delta P with a shop vac (we have tried). An ejector type vacuum generator (works off air pressure from the pneumatic system) will generate relatively high vacuum,. but only if you have a tight seal. We were successful in 2008 with a shop vac arrangement because we had a huge area to work with. We were less successful last year because the available area was too small. (that’s why we abandoned the vacuum after Peachtree)

I am not saying don’t try it! please do, and I hope you are successful. I just want you to be aware of the challenges and available options. If you have any questions (vendors, how-to etc), PM me and I will try to answer.

10

My post was indeed a joke. I would strongly caution against a vacuum this year. If for some reason you still want to pursue a vacuum gripper then Martin is without a doubt the man to get in touch with.