Ball posession: Roller (ball magnet) or vacuum?

[ubermeister]

How are you possessing the ball? How well does it work? Any innovations from the original ball magnet or standard vacuum design?

We went with a vacuum and are very pleased with the results. It uses an ungeared FP motor and a 5" shop vac impeller. The end-effector is a thin plastic food container. We can drive at full speed while maintaining control of the ball.

It seems most teams went with roller designs. I'd be interested to see how these compare to vacuum designs.

[robself705]

We went with vacuum but actually added a ball magnet to grab moving balls and push them into the vacuum. It works very well for us. We can easily score three shots in 20-30 seconds if balls are nearby the bot.

[joek]

we tried a ball magnet, but it didn't work, it just sucked the balls under the frame

[BradMello]

AIR Strike is using a vaccum.

You can see it in this video:

Click

[RMS11]

@ people using vacuums with those yellow funnels, where do you buy them? I looked around mcmaster but didnt see them...

[ravichauhan]

We are using a vacuum with a mcmaster carr plastic funnel. it worked but it will be more efficient to have a silicone one which we will attach before competition. we are using the fifth CIM for the vacuum because we are using the FP's somewhere else. Its speed is geared up 3:1. That will also be changed before competition to 5:1. What type of rpm are you other non-geared-FP guys getting

[fuzzy1718]

to those using the vacums, how are you stopping the suction when you kick? or are you?

[BradMello]

Originally Posted by RMS11

@ people using vacuums with those yellow funnels, where do you buy them? I looked around mcmaster but didnt see them...

Home depot is where we bought ours.

Originally Posted by fuzzy1718

to those using the vacums, how are you stopping the suction when you kick? or are you?

Just shutting off the vacuum prior to kicking equalizes the pressure fast enough that the ball will disconnect when kicked.

[Vince]

I spy, with my little eye, two dog toys....

[Austinmead]

how'd you make the vacuum?
we know you replace the old vacuum motors with the FP motors but we cant get it to work

[Dkt01]

We're using a vacuum, but all our driver training was done without a ball possession device. Therefore, we may not end up using anything.

[Bruceb]

As robself said earlier we use both a ball magnet and a sucker. The sucker is 2 shopvac impellers stacked back to back so that the output of the first feeds the input of the second. They are powered by 2 FP motors geared UP 2 to 1. Impeller rpm is about 19,000. Way much suck. We can move anywhere as fast as Robbie can drive and not loose the ball. We have the vac arangement at the back of the bot and the toilet plunger that sucks the ball at the front connected by 1.5 in. pvc with a wye in it. At the wye we have a small piston that holds a flat chunk of rubber over the hole. about 5 ms before we shoot we pull the piston and dump all the vacuum so we kick straight. This is VERY effective. We were the high scoring first zone bot at the Wisconsin regional and ended on the 2nd place alliance.
Bruce

[Austinmead]

sweet... thats cool....ill look into designing that lol

[nighterfighter]

Originally Posted by fuzzy1718

to those using the vacums, how are you stopping the suction when you kick? or are you?

We used a dump valve.

It is just a PVC pipe hooked up to the vacuum, with a pneumatic cylinder inside of it, to open the top. It gave us 5 different kicking modes, (Long w/dump,w/out, med with, without, short) with some great consistency. We would open the dump valve about 10-25ms before we kicked.

[RoboTigers1796]

Originally Posted by BradMello

Home depot is where we bought ours.



Just shutting off the vacuum prior to kicking equalizes the pressure fast enough that the ball will disconnect when kicked.

Do you happen to have an item # or a description of its real use? I just spent 2 hours in home depot looking, and the employees are no help.