How to pick up a frisbee

[NanoCollins]

Originally Posted by Wildcats1378

That's the easy part. The hard part is determining which way they are facing, and then how to flip them.

I think that picking up the frisbees is going to be a waste of time. There's a pretty small number sitting on the field, and the main way to get most of the frisbee's is through the feeding station.

However, I was thinking of a conveyer system which would have a little hatch open. Above the hatch would be a suction cup on a piston. It would go down, pick up the frisbee, then deposit it on the conveyer belt. Simple and fast. Doesn't solve the upside down issue though...

From what I have seen from other people's test, it does not matter all that much how they are flipped. Upside down or not (depending on your shooting system and the distance) they should fly fairly well.

[TheOtherGuy]

We bought a few suction cups at ACE for about $0.50 ea. along with a 3" ABS tube and some screws. It works quite well, actually, we just have to figure out how to get them from the suction cup to the hopper/shooter.

[3044smike]

my team had a few ideas for flipping the disks but the one i like the most is a system where the disks actually come into the robot on the side and then at the end there would be a little motor with two sticks with gear interactable teeth (don't know what they're called ) which would push the disk one way or the other based on a distance sensor. Any thoughts?!?

[3044smike]

Originally Posted by NanoCollins

From what I have seen from other people's test, it does not matter all that much how they are flipped. Upside down or not (depending on your shooting system and the distance) they should fly fairly well.

my team did a little testing and the upside down frisbees are fine and dandy for about 20 ft if you can throw it really hard with alot of spin but then it just drops like a rock

flipping disks might still be important

[Libraryfanatic]

Originally Posted by MrTechCenter

Sure it's much easier to go across the field to your alliance's feeding station and grab four discs, but think about it. After autonomous mode, you'd have 3 robots fighting for discs at the alliance feeding station. Sure there's enough slots for all three to be filled at the same time, but realistically, all three would not be fed at the same time, as the corner is very small and can barely fit all three robots there assuming that they are average sized. Plus, you have to worry about d-bots getting in your way and defending your feeding station. If you can pick up discs from the ground quick enough, it would be a HUGE advantage to you, and it would be beneficial during autonomous too, because then you can pick up discs from the ground and shoot them during auton for additional points (after you've shot your preloaded discs). And as for there being a lack of discs on the ground, the goals are fairly large but with the amount of defense that's possible, I can see a LOT of missed shots when a d-bot knocks a scoring bot off of alignment. We saw this last year with fender-shooters and d-bots.

There are three feeder stations-no competition at a given station.

[gabrielau23]

Well, I've flipped sides on collecting off the floor. I was pretty adamant in an earlier post about off-the-floor collection, but I have to say I agree with Joon now. Collecting will be a definite advantage, and in the final 30 seconds I could see teams scoring a lot from the discs thrown across the floor. Also, teams will probably miss at a higher rate then 85% unless they're "elite". And there's a reason there aren't that many "elite" teams. Picking up, I think, is going to be a very good thing to have. And yes, I everybody permission to make fun of me for flip flopping like this on this issue.

[3132MentorMike]

All good engineers proudly say, "I was wrong" if the data supports it.

[bobbyball]

Originally Posted by kuraikou

But than how would you put them into your shooter?

just use a pully and belt system upwards

[GaryVoshol]

Originally Posted by Rishabhgadi

Our team has been debating whether to use a shooter, or an arm. we have a prototype shooter but not an arm...Any input?

So you're going only for the LOW GOAL? Maximum extension of an arm is ~5" short of the MIDDLE and ~20" short of the HIGH GOAL.

[bobbyball]

Originally Posted by Wildcats1378

That's the easy part. The hard part is determining which way they are facing, and then how to flip them.

I think that picking up the frisbees is going to be a waste of time. There's a pretty small number sitting on the field, and the main way to get most of the frisbee's is through the feeding station.

However, I was thinking of a conveyer system which would have a little hatch open. Above the hatch would be a suction cup on a piston. It would go down, pick up the frisbee, then deposit it on the conveyer belt. Simple and fast. Doesn't solve the upside down issue though...

it will have to depend on the constictors of the belt shelfs

[Dan Oelke]

I created a prototype last night to sweep up the frisbee. This was using a 3/8" piece of plywood with about a 1/8" gap under the plywood. The frisbee would pretty consistently pop up onto the ramp.

There are 2 small wheels by the front edge. The idea being that those wheels will keep it from catching on the bump in the carpet. This also had 2 castors on the back edge of the ramp putting it about 4" off the ground.

http://www.youtube.com/watch?v=M7JbdU4h6F8

[Wyrdash]

Originally Posted by Dan Oelke

I created a prototype last night to sweep up the frisbee. This was using a 3/8" piece of plywood with about a 1/8" gap under the plywood. The frisbee would pretty consistently pop up onto the ramp.

There are 2 small wheels by the front edge. The idea being that those wheels will keep it from catching on the bump in the carpet. This also had 2 castors on the back edge of the ramp putting it about 4" off the ground.

http://www.youtube.com/watch?v=M7JbdU4h6F8

It looks like this prototype is using hard brushes, something more sticky, or at least not dry nylon brushes will probably work better.

[Djur]

Originally Posted by 3044smike

my team had a few ideas for flipping the disks but the one i like the most is a system where the disks actually come into the robot on the side and then at the end there would be a little motor with two sticks with gear interactable teeth (don't know what they're called ) which would push the disk one way or the other based on a distance sensor. Any thoughts?!?

Those would be rack gears.

Why would you need to push the discs one way or another? Would you have two shooting mechanisms?

[Bruceb]

All this talk of weather to pick up from the floor or the feeder slots. I dont realy think it is that hard to pick up from the floor and I have devised a realy simple disk flipper that is integral to the conveyor and needs NO SENSOR. So, why not do both. If you are picking up from the floor then you have some kind of hopper. If you have a hopper then it should not be that difficult to collect from the feeder tubes. For that matter, if you can pick up from the floor you can pick up from the floor right in front of the feeder station. Put a sign on the bot for the human player " feed to floor".
I'll post a vid later showing the flipper.
Bruce

[Bruceb]

Additional note. Look at the flipper this way. If you lay the disk on the floor the leading edge of the disk is HIGHER if the disk is upside down. Yes, there is your hint.
Bruce