Lobed Gears For Bouncing Bat Halloween Question

I found some $1.49 rubber bats and I'd like to make them bounce up and down and maybe move up and down in a smooth linear fashion while bouncing. They weigh practically nothing so I think this would be a good first start for me in Arduino controlled electric motors.

Off hand, it seems the best way to achieve this is with an electric motor with a lobed gear much like that of a camshaft with some kind of lever on top of it which has the string mounted for the bat. I'm at a loss as to how to deal with the gearing. It's going to take quite a bit of trial and error to find the right sizes, ratios, rpm, etc.

Another option may be to use a standard round gear and then attach a lever to an offset hole in the gear somehow.

  1. Where does a person find a "gear kit" to do a variety of experimentation? My usual web skills haven't been of much value here.

  2. Any specific recommendations as to a better method of making my bat bounce? I tinker with Arduino almost nightly but I don't have much awareness as to the components out there for creating movement.



You can use a continous rotation servo with a linkage to make something go up/down or back/forth.

Or you can use a normal servo motor with a wire connected to the horn going through a hole, to translate the rotation from say 0 degrees to 90 degrees to up/down. Here is a site that talks about servos: Make: Projects.

In terms of where to go, I suspect the best place is places that caters to robot building and radio controlled cars/airplanes. Given it is the first week of October, you probably don't want to go to Chinese internet shops if you want it for this Halloween. If you live in the USA, two US distributors I would suggest are:

Besides robot/rc shops, you might want to check out your local toy store and Radio Shacks for the various science toys, etc. You might also browse the Halloween stores that might have various things that could be modified. These places are probably better visited in person, than trying to order online.

Thanks guys. My camshaft idea was way off. This should be rather straight forward with a servo. Thanks for the links and tips.