Minibot Questions

Instead of making a new post for each question that was about the same mechanical component, I decided to make one post for all.

  1. Can we use a clevis and control horn like the ones used in RC Airplanes to Open/Close the hinge mechanism to hold the minibot to the pole?
    http://www.servocity.com/assets/images/GPMQ3900_Control_Horns_with_rod.jpg

  2. Since coiled metal springs are not allowed on the minibot (http://forums.usfirst.org/showthread.php?t=16517), and our team was planning to use compression springs to keep the “jaws” open until the minibot reached the pole, what substitution with surgical tubing could we use to keep the “jaws” open until the minibot reaches the pole.

3)Could we use polycarbonate pulleys for our closing plunger mechanism. They won’t be contributing to any vertical movement, only to guide cable so they can pull the “jaws” close.

  1. No, unless you make it yourself out of raw aluminum sheet. <R92-H>
  2. You can make your own compression spring by taking a piece of polycarbonate, and simply bending it. <R92-F>
  3. My first assumption is that polycarbonate pulleys are illegal, but I would suggest a Q&A on this one.

GDC isn’t saying anything about form polycarb can take, other than a very broad “Polycarb is legal, and there are no restrictions on form” in http://forums.usfirst.org/showthread.php?t=16317

I’m pretty sure for the poly pulleys you would have to make your own for it to be leagal, however I am not sure enough that you should give up, I agree with the suggestion to Q&A that.

Won’t polycarbonate snap if it’s bent so far?
Would a steel cable be considered legal?

Not if you do it right. Not being entirely certain of the method there, I’d say to find 1714 (or Chris is me) and ask them.

Steel cable: Not legal on the Minbot. You can use non-metallic rope or cord.

Henry, check the Q&A I linked to again.

Oh,okay sorry about that then.

Another question that goes off topic from here.

Would it be illegal to use a jaw and cone clutch for our minibot mechanism? It would be connected to one of the motors the main drive OR just another motor we have running and propel the launching mechanism forward until a limit switch stops it.

As far as bending polycarb goes, it helps if you heat it first. We have an electric heater for just that purpose but you can also get the job done with a Heat gun if you’re careful. But as you bend it (especially past 90 degrees) the material gets thinner and slightly more brittle (because you are actually stretching it) so it does have its limits. We had to get pretty good at this for our minibot

I don’t think that would be legal, unless you could built it out of the allowed materials.

Only if you can construct one using the allowed materials in R92 and you have two or less Tetrix motors.

does anyone know what we can do to get the minbot down from the top of the pole? can we shake it? and we bring large extensions to get it down?

No specific prohibition against shaking the pole yet from GDC but Update #6 specifically prohibits use of any mechanism (stick, etc) from being used to retreive your minibot…

How about threaded Aluminum rod. Is that permitted for use on the minibot?

Modified by TU #6
<G59> TEAMS must retrieve MINIBOTS from the TOWER quickly and safely without special equipment and while standing on the floor after each MATCH. Violation: The FIELD crew will retrieve the MINIBOT. A second violation may result in a YELLOW CARD.

It is expected that a MINIBOT will be able to be retrieved from the TOWER in less than 1 minute. If the FIELD crew has to retrieve the MINIBOT, they are not responsible for incurred damage to the MINIBOT. If a MINIBOT is deemed dangerous (i.e. in its design, or in the way the TEAM retrievese it from the TOWER), the Referee may issue a YELLOW CARD to the TEAM associated with the MINIBOT.

As to threaded rod, only if you can make it from…
H. Raw aluminum sheet, 90° angle, u-channel, tube, bar, that is not sold in pre-perforated or pre-punched form.

I would suspect that you could get round Al bar and thread it. Whether you can get it to fit into the Minibot volume and still come down enough to get the Minibot easily is a little trickier.

I suggest teams put a hook or ring on their robot that gives an obvious place for the Field Personnel to grab the minibot. You should do this even if you are planning to have the robot bring itself down because things don’t always go according to plan.

ChrisH

GDC decided it’s a fastener:

http://forums.usfirst.org/showthread.php?t=16667

Hello Everyone! Does anyone have any ideas whatsoever abut the deployment of the Mini-bot? any advice or ideas from any team would be treated with the utmost appreciation!! Thank You! :slight_smile:

Team 2389

Go to Youtube, type in FRC minibot and observe closely;)