Re: 10 Balls per second?
 

(I didn't actually run these numbers) But if you did run the CIM that fast then wouldn't the first balls out exceed the 12 m/s speed limit?

On another note, I also hear machinery running during the film. I can hear a soft "thump thump thump thump" before they start appearing on screen and traveling towards the hoop. Presumably noise made from exiting the shooting mechanism.

Re: 10 Balls per second?
 

* This Robot powered by Divine Intervention *

(and WD - 40 )

Sure.....but
 

keep in mind that it will take a while to spin up a wheel to 1750 RPM, so by the time it speeds up you may only have a second or two to shoot all the balls. Total time to shoot 10 balls is not 1 second, but 1 second plus the time to speed up the wheel (perhaps almost 10 seconds depending on how you design your system)

Yes, if you just let a wheel go at the full speed of the large CIM it may provide too much velocity, but it depends on the wheel diameter (well, actually the radius really).

My calculations (which I will not post here) show that you have to be a bit careful with the diameter and inertia. However, there will be plenty of energy in the wheel to fire off a bunch of balls (remember, its not just the motor power that is shooting the balls, but mostly the energy already stored in the wheel which is really a flywheel). Its almost a given that you will have plenty of energy to shoot all the balls when your wheel is up to adequate speed to give you the velocity that you want.

You might want to consider gearing for the wheel as well - my calculations show a real benefit to this (but you will have to figure out just what it is). I will leave it to you to do the energy, inertia, speed, and power calculations.

Dont forget that the velocity of the balls will be slightly different as well since as the wheel slows down with each shot, the subsequent shots will be a bit slower,which means that the range will make a difference as to how many balls you can actually get into the goal when shooting them that fast.

Re: Sure.....but
 

Not really...the regular CIMs spin somewhere between 3000 and 5000 rpm, and you can spin them up (attached to a 6" wheel) in less than a half second. If you're gearing it with sprockets or using a heavy wheel then yes it will take longer, but i don't think it'll take more than a second or two

Re: Mind tricks on CD?
 

You'd be wasting balls, not really power. It doesn't take that much more power from the launcher to launch 10 at that rate. They only have to run the device for 2-3 seconds top maybe to launch 10 balls, including acceleration. To launch 1, you reallistically couldn't cut it off in under a second, especially factoring in acceleration. In fact it's probably far less energy than having to re-accelerate the motor after each shot or spacing the balls out so they shoot rougly 1 per second. The same pretty much applies for whatever feeding mechanism you use. Rate of fire has alot more to do with how you feed the balls (or prevent them from being fed pre-maturely, aka when the motors are accelerating up to speed) than the launcher itself.

Re: 10 Balls per second?
 

what i might want to ask is with this mirical and ingenious shooter mechanism, how are the balls aimed. can the camera sync with that many shooters?

this is just a question.

also this mechanism: does it use pneumatics as a feeder? it seems like the nly thing fast enough.

jury rig wheels to the bottom. that would make a killer robot that would probably win

Re: 10 Balls per second?
 

Actually, I do hear a sort of dull thud right before the balls come flying, and it sounds like its real...but I'm going to say there is no bot that can pull this off.

Like you said, they look like they are falling down. For them to be doing that, they would have to be exceeding muzzle velocity constraints. And the shot is very jerky, like it was sped up.

I dunno for sure, but I'm pretty sure this is fake.

Sorry if its real, so offense...

JBotAlan

Re: 10 Balls per second?
 

just from watching it with out sound it looks like its been made faster and played backwards. and as for the upside down part, unless they put a light on the floor, how do you explain the glimse of light at the top?

I think its real but a tad bit altered and not mounted on a robot.

But then again it could be anything

Re: 10 Balls per second?
 

Ok, this is a little suspicious. :rolleyes:
The balls are coming from the same area, there was a slight delay between the first and last balls, and there was a lot of static noise in the video.

I'm going to theorize that 968 decided they had a little spare time at the end of their day, parked something in front of the goal other than a robot, and then let it rip.

Yet again, that's just a theory. Good luck to 968 and all teams! This game will prove to be interesting when it comes time for competition.

-Joe

Re: 10 Balls per second?
 

It could be gravity fed ;)

Re: 10 Balls per second?
 

actually i dont think gravity would be fast enough to feed at THAT speed.
i mean doesnt gravity have a limit? it would already have to be moving downward to hit that velovity to feed them in that fast.

Re: 10 Balls per second?
 

Re: 10 Balls per second?
 

actually this mechanism would be perfect defense.

it could shoot balls straight up and catch them and just park in the center goal and knock out any balls shooting for the goal by bouncing them against one another.

Re: Sure.....but
 

compressed air assist? :D

Re: Sure.....but
 

Doesn't it take time to compress the air as well?

EDIT: actually now that I think about it I remember something about being allowed to start with the tanks full.