pic: 4587 CAD (With a Shooter Mech.)



4587 Near final CAD, this one includes it’s shooter mechanism. We are pretty sure this will be the shooter on the bot however, we have the ability to easily swap shooters out.

Whats the gray gearbox on the cim in the top left-ish? Doesn’t look like any I recognize.

maybe this

http://www.andymark.com/product-p/am-0401.htm

Looks like a GEM gearbox.

Huh, I forgot about those.

You guys were correct it is the AM GEM Gearbox with 4 stages. We ran those last year on our climber and we were very pleased with their performance. One of those boxes with 3 stages had enough power to pivot our entire robot back and forth for our climbing mechanism. They are pretty tough too.

Does the roller on the arm interfere at all with the trajectory of the shot?

Not at all, before we shoot we plan to open up the jaws all the way (or just enough) with the gearbox mounted on that pivot point. You can see it here:


The ball will have a straight path out of the shooter other than the two prongs keeping it in the shooter at the bottom.

The arm will also be able to open really wide to catch as well. Logistics of that are still being worked out.

Ah there’s that shooter that I couldn’t find on the last picture!

Yep.! :smiley: We are going to use 19mm Spear gun latex band. So basically really thick surgical tube. :stuck_out_tongue: The plan is to have a winch gearbox that will retract the plunger that has a quick release, as well as have a worm gear driven pulley that will tension and release the Latex band for different shooter distances. If it makes sense…

Is anybody else doing this? Some members of our team really liked it, but we’ve seen many prototypes with pneumatic cylinders that hit the ball which fail miserably. Would a hammer/arm work well with this idea?

Thanks in advance :slight_smile:

Have you considered a pneumatic cylinder for this articulation? There are a few advantages. The piston provides the roller with greater normal force for intake. Software is also less complex for this motion. We are using a piston that travels from wide open to a bit under the actual resting position of the roller with a ball inside. It saves us a motor, gearbox, speed controller, and a piece of code to debug.

We are going to start with a motor there but we have the option to put a piston in there as well. We like having a motor there due to it’s unlimited ability to pivot open and act as part of our catch mechanism.

At the moment the shooter is not using pneumatics at all. That plunger that you see is going to be powered by really thick surgical tubing. Out prototype of it as well as many other teams work really well. A piston in place of the surgical tube to power the shooter has not worked well for anybody as far as I know. The piston just does not have enough acceleration combined with force behind it to push the ball out and into the high goal very well.

Go for it. I’m sure it has advantages. That said, do you really need any more positions other than “closed” and “open enough to catch”?

Your front wheels look smaller to me than the other two pairs, is this true or am I just seeing things?