Chief Delphi - 3753 shooter. 12 points in 2 seconds

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3753 shooter. 12 points in 2 seconds

So we are done with our shooter in week 3 and after shooting with our best we got all Frisbees in the same spot in only 2 seconds. We have a video where we shoot faster but for safety we just keep this one. What do you think? (Video says 3sec but I'm almost sure its 2:D )

http://www.youtube.com/watch?v=w-Z6g8521rk

Re: 3753 shooter. 12 points in 2 seconds

Wow! Awesome job with that! Will we be blessed with any description of the shooter?

Re: 3753 shooter. 12 points in 2 seconds

Are you using a linear or curved shooter?

Re: 3753 shooter. 12 points in 2 seconds

Quote:

Originally Posted by Physicguy (Post 1223282)

Are you using a linear or curved shooter?

It's a two-wheeled linear shooter.

Re: 3753 shooter. 12 points in 2 seconds

Here's two more videos of us shooting in this video: http://youtu.be/muhzq_TwARc

Re: 3753 shooter. 12 points in 2 seconds

That is pretty sweet. Im a bit surprised you guys can fire that fast without it slowing down.

Re: 3753 shooter. 12 points in 2 seconds

Quote:

Originally Posted by darkember (Post 1223321)

That is pretty sweet. Im a bit surprised you guys can fire that fast without it slowing down.

We were a bit surprised too.
Once we played around with shooting from our spot in autonomous, we discovered that we only need 35% power on the wheels, due to our shooter's angle. But we can't shoot the frisbees nearly this fast at the lower speed (video shows 100% speed iirc). Instead, we have to wait roughly 3 seconds between shots. Need to test it more though.

Re: 3753 shooter. 12 points in 2 seconds

That is totally awesome.

Thanks for sharing your design and some of the data you have collected to date. You are doing a good service to the entire community.

Re: 3753 shooter. 12 points in 2 seconds

http://www.youtube.com/watch?v=OvAz_P7WR38

Here is another video with a much faster result.

Re: 3753 shooter. 12 points in 2 seconds

Today we shot 4 frisbees in 1 second. Here's the video.

Re: 3753 shooter. 12 points in 2 seconds

Your shooter looks amazing! Would you mind explaining it in further detail? How can you shoot so rapidly? What kind of motor/gearbox setups are you using? How much squeeze do you put on the frisbee? How much room is in between your wheels?

This looks like an awesome design. I can't wait to see 3753 in action this year. Keep up the good work!

Re: 3753 shooter. 12 points in 2 seconds

Quote:

Originally Posted by ctccromer (Post 1224156)

Today we shot 4 frisbees in 1 second. Here's the video.

That appears to be a truly top notch shooter.
Tag on a level one pyramid climb and you'll be doing really well at most regional events.
Best of luck at the competitions.

Re: 3753 shooter. 12 points in 2 seconds

Quote:

Originally Posted by Andrew Lawrence (Post 1224164)

[Warning: I'm a programmer, not a mechanic. Sophisticated vocabulary inbound]
We actually didn't do anything complicated, it just all worked REALLY well!

Our shooter is pretty simple: Two CIM motors with Pneumatic wheels attached, and a Window Motor with a small piece of L bracket stuff attached to the plastic black wheel thing. The window motor and its attached arm push frisbees into the two wheels, which then shoot the frisbees. We put stoppers (screw) in the way of the window motor's arm so it could only turn so much either way.
If you look at the first video in my signature, you'll see some pictures of the shooter before we put our feeder on top.

As for shooting fast, I programmed the window motor like this:

Code:

When button 3 is pressed

1) Set the window motor's output to -1 (forward.  We mounted the window motor upside down, so the (-) is forward and vice versa)

2) Wait x miliseconds

3) Set the window motor's output to 1

4) Wait x miliseconds

5) Set the window motor's output to 0, ending orders to the arm (so that it doesnt CONSTANTLY try to push against our stoppers and mess up the motor)

I'll attach a picture of this for anyone who's curious how to code it. As someone who's new to labview this year, it took me a while to figure out

The way the code is set up, hitting the button ONCE will make the action run once -- it doesn't matter if you let go of the button before the sequence ends, it will finish the whole order. If you hold the button down for longer than the duration of one sequence, it'll loop repeatedly. Since our stoppers are FAIRLY close together, the arm only turns about 70 degrees, meaning it doesn't take long to go from one stopper to the other, so it can go forward and back in a fraction of a second. Looping it gave us the results you saw

Hope this helps! Now we just need to decide on a climber (and a climbing destination) ;)

Re: 3753 shooter. 12 points in 2 seconds

Quote:

Originally Posted by Andrew Lawrence (Post 1224164)

Thanks! I believe there are ~10.25" between the wheels and a piece of skateboard grip tape backed by two stacked pieces of 1" aluminum square tubing. HOWEVER, .75" isn't the true amount of compression of the disk, because the wheels are Andy Mark pneumatics with a low amount of pressure in them (~7-10 PSI), so the wheels themselves compress quite a bit, giving us a large area of contact between each wheel and the disk. The wheels are roughly 1.5" apart from each other. There is an arm attached to a window motor that pushes the disks from the hopper, a 5 gallon home depot bucket, to the shooter itself. the arm is made from a piece of 1" aluminum angle with one side cut in half so that it only pushes one disk at a time.