Re: ball cannon???
 

think one thing wiffle ball because this ball is just like a wiffle ball its really hard to control the movement of the ball and its so light it will be hard to throw very far

Re: ball cannon???
 

I definitely have an idea for at least a 40" tall hopper, basically the dimensions of the drivetrain with a turreted shooter at 40"+ I am not planning on posting up the design or anything but so far its looking like it can be done fairly easily with room for at least 20 balls. Also throwing the balls is quite simple, at least for my team. :cool:

Re: ball cannon???
 

I assume a suction device on the bottom for added traction is a given?

How much force did you guys get out of that sucker in '08 anyhow? :)

Re: ball cannon???
 

Of course. Last year we had around 400lbs of force. We might just suck again this year :cool:

Re: ball cannon???
 

Heck yea, we're doing a shooter too. I prototyped a successful launcher yesterday that went 8 feet, and the students are almost done prototyping a shooter today. Combine it with a turret and camera and you're golden -- they key is the type of shooter. Get creative, you don't have to use flywheel style...

We're not using a hopper though. Our overall game strategy dictates that we won't have the time to collect large amounts of moonrocks, so we'll fire what we get almost as soon as we get it. We'll have a max of 6 moonrocks in our bot at once, and probably then only at the start. This is for simplicity's sake though...

Re: ball cannon???
 

I don't pretend to know much about this, but wouldn't all the holes in the ball make suction difficult?

Re: ball cannon???
 

More like impossible :)

Re: ball cannon???
 

I know the location of a few wind tunnels that could probably do a fair job at providing enough suction to suck up a ball... but you aren't going to be able to get those under the weight limit, or even run them on a simple 12V battery.

So for all intents and purposes, suction on the entire ball can easily be considered impossible within the scope of the competition. However, a robot could *theoretically* suction a small part of a ball - one rib - and provide enough force to grip the ball. That is, if you have a mechanism that is sophisticated enough to be able to target and approach a single rib on a ball.

Re: ball cannon???
 

You weren't around in 2006, were you?

Re: ball cannon???
 

lucky, you guys get to start prototyping already? we are sitting around tossing around ideas... maybe today....

my $.02 (ok the second ones) Ill agree that the dang irregular shape will make it interesting to throw, we where planning along the lines of a few spinning wheels (kinda like in '06) but we keep thinking of the issue of the wheals getting stuck in the gaps...

Re: ball cannon???
 

In my opinion, a "pitching machine" is the way to go. Though the MoonRocks may look different than the Nerf Balls we used in Aim High, they still have enough shape to act like a ball. I think trying to pin down a robot and dump the MRs out and into the trailer will be a pain.

I think we're going to use the camera and tracking to hit our mark.


Hopefully that physics we learned about will pay off!

Re: ball cannon???
 

...Why not do both? Be able to pin em down and dump into their trailer, or just rip shots off at them from across the field. I predict the robot that does both well will win this.

Re: ball cannon???
 

Would it be legal to have a ball cannon that'll shoot backwards in order to block other balls??

It may difficult to coordinate the "collision",but is it even legal trying?

Re: ball cannon???
 

I think shooters are possible and you WILL see a lot of teams doing it this year.
The most effective of the teams trying to do so will most definitely be using the camera to do this. FIRST has done everything to encourage this with the inclusion of a camera/lazy susan in the kit and flourescent colors on the trailers.
Go figure. ;)

Re: ball cannon???
 

We were also considering a "launcher" type mech. It would be hard to aim but using a dumper type you'll loose all your game pieces at once.

The use of a "harvestor" type ball collector.. is this even legal? Read the rules a few times and it really dosn't say either way except that you can't herd game pieces.