Help purchasing the right motors

[Jumbosize]

Hello all,
I'm currently working on a group project in my College Freshman Engineering class. The project is that we have to build a device that can dispense marbles into pits that are all at varying distances from the starting location. They are all between 2-5ft away from the start.

My group decided that the method we are going to use to actually launch marbles will be using two parallel motors that will work like a small scale version of those automatic football throwers.

While I do feel that I know a fairly good bit about general electronics, I don't know much about motors. So would somebody be able to direct me to a place online where I could buy motors capable of this?

What I'm really look for are a pair of motors that are strong enough and fast enough to launch a marble about 2-5 ft. I'm also hoping to find some that can be powered by a 9v (or anything smaller, there is a size restriction on batteries), and preferably something that won't be outrageously expensive. I'm hoping I don't need to spend more than $15 for each motor, but if I have to I will.

Any tips/suggestions will be greatly appreciated.

 

[Fish4Fun]

Jumbosize, Welcome to the forum.

@==> Source of motors? Radio Shack, Ebay, Hobby Shops (online and local) etc.

@==> Idea.......prolly really need to re-think your launch system. Sounds cool, but highly improbable it is going to have any degree of accuracy. Engineering is as much about choosing the right starting place as it is building something. Just because something is simple does NOT mean it is not the best solution. I would SERIOUSLY consider a variable inclined plane with a groove and perhaps (if you want to get really fancy) a sighting system.

Fish

 

[Jumbosize]

Thanks for the input!

I know what you mean about motors being unreliable but we have actually thought of a way to control this. Also, I don't want to go into great detail on the requirements of the assignment but for various reasons an inclined ramp would not be acceptable. I know I am sounding like a stubborn hunk, but we plan to use motors.

And what I was actually asking is what type of motors I would be looking for. I'm not entirely sure how to pick out a pair of motors that would be able to do what I'm hoping for.

Thanks!