Questions about shooter Prototype

Hello everybody, my team is crunched for time as I imagine 75% of teams are. Anyways, this is our prototype for our shooter (minus the wooden ramp for the ball). I have two questions regarding the finalization of this design…

http://imgur.com/a/WoB5n

  1. Has any team made some type of deployment system? To expand upon that, a system that enables you to expand the shooter outside the robot once the match started. In this motion (<— --->) I was thinking of some sort of piston and rail system. See my cheesy picture.

  2. Holder for ball? Can we bend some sort of material?

Thanks for the replies. -Randy L. ::ouch::

Hi Randy,

I’m mighty sorry that I’m the first to address your question, as I know it’s been up for a few hours and that time is really of the essence, especially given the nature of your questions and the lateness of date.

If I understand you correctly, you are showing us the state your shooting mechanism currently is in, and telling us that (1) it is too wide to fit within the perimeter of the robot, and therefore would need to be “deployed” to the sides once the game started, and (2) you currently have no method for holding the ball before being shot. You haven’t addressed wether you have any of the other critical systems already in place, such as picking up a ball from the ground, but given the other things you said I’m skeptical that such things have been addressed by your team.

If I’m wrong, and your team already has a ball intake, your drive base is complete and fully functional, and the only things you need are what was listed, then perhaps you could deploy using pneumatic pistons that push your system components on slides (such as heavy duty drawer slides) to a pre-set end, where they latch in place. A ball holding mechanism could be as simple as a hoop of bent EMT pipe, or a sheet of Lexan, though from your description it’s hard to know what you might need. You would need to do research, and prototype with available supplies until you had something satisfactory.

My fear, though, is that your team needs much more than a few ideas. If you really are still in the early prototyping phase on a major mechanism, and are missing other key pieces entirely, you need to rethink your plan going forward. It will be very difficult to come up with unique mechanisms, and integrate them into a working system, with so little time left. I highly recommend that you look at the mechanisms for picking up, holding, and launching the ball that were used for the Robot In Three Days build, especially team Boom Done, and see if you think you can add such systems to your robot. If you do, then start immediately to design and build, and plan on working long evenings from now 'till Tuesday. If you don’t think these ideas are feasible, then I would (a) complete the drive base, making sure it is robust; (b) create a mechanism that can control the ball without picking it up off the ground (i.e., roll it with your robot), and which can let go of the ball in order to pass, and integrate this into the drive base; © build bumpers that comply with the rules; and (d) get as much practice driving as I possibly could in the next 4 days.

Please consider with your team, quickly and carefully, your path forward. You don’t want to come to next Tuesday and find yourselves without a robot that can do anything! Make sure your robot is built within your means, and that it can (at the very least) drive well, and consistently hold and pass the ball. Good luck.

Thank you for the response. My team has our chassis moving and the picker upper mounted/deploying. Our last concern is the shooter which we are vigorously building and trying to perfect. Our last resort will be a 1 point shooter but hopefully it does not come down to that. Our team has had a few prototypes but none of them were working to the standard we would of liked them to.

Be aware that you have a 45lb withholding allowance (normally this is 30lbs, but was increased to cut some slack to teams that lost a lot of time to weather).

What this means is that you can bring 45lbs of pre-fabricated/assembled stuff
to a competition, and simply bolt it on to your robot (anything that comes assembled does not count, like motors, or assembled gear boxes, but anything that is not assembled when you buy it counts towards the 45 lbs).

If your still working on your shooter, you can attempt to take advantage of this by removing your shooter and working on it apart from the robot, or by building parts to put on to the shooter when you arrive at the competition.

I hope this doesn’t come off as discouraging, but I feel like some strategic advice may be helpful. If you have any veteran teams in the area, I would strongly suggest reaching out to them as soon as possible; otherwise, you should go in search of help as soon as you get to your first event (you would be surprised how helpful your opponents can be)

While you probably could come up with a design that allows you to shift your arms in and out of the robot, it may not be a simple thing to do in a robust way. Once you get the arms spread out, you’re exposing a vital part of your robot to the field and other robots. While it’s unlikely anyone would intentionally try to smash your shooter, it is bound to get hit by other robots at some point.

Also, keep in mind that you will not be playing your matches alone; you’ll have other alliance members that can often do the tasks that you cannot, and you are often better off doing a few things very well (ie: quickly and consistently) than being able to do everything slowly.

In this game especially, there are pretty well defined positions on the field (all 3 alliance members will not be shooting in the high goal), you can contribute as much to your team by sitting in your alliance zone receiving the ball from your human player (a catcher type design would make this really effective) and quickly rolling it out of your robot to the mid-fielder, as you can by throwing the ball into the high goal; if this is all your robot can do, but you do it really well, you would be a fantastic 2nd pick for eliminations. Even if your qualification matches suffer because you don’t have a good scoring mechanism, the good teams do take notice of robots that will make a good second pick (eliminations captains will usually have good scoring mechanisms, the first pick will likely have some way to throw the ball over the truss, however the the second pick doesn’t really need either of these things).

That being said, if you have the ambition and resources, you can certainly try out your mechanism idea. I would recommend trying to use pneumatics for this task, while they have quite a few draw-backs (like running out of air, added weight, limited range of motion), they are very easy to program and are extremely consistent (something to keep in mind for your next season as well).
Alternatively, you could find some inspiration in the various robot-in-3-days teams.

If you have to make a tradeoff between being able to shoot at the goal and being able to get the ball over the truss, you should probably favor the truss, both are worth 10 points, but the truss is really easy to score, and the penalty for missing is negligible in most cases. A high-goal shooter needs to be accurate, as a miss will cost a lot of time; you will likely find that more experienced teams are going to be reluctant to yield the scoring position.

Here is a web page showing season2014 teams in New York:

http://frclinks.frclinks.com/t/NY-USA/2014

On that web page, you can click on the team number to take you to an information page for that team which shows what events they are planning to attend. Most teams have a team website, and the team info page will have a link to the team website, where you can find contact information.