My comments on shooters

[jgannon]

Originally Posted by Woody1458

I am more worried about the annoyances and game delays of having the Dj station getting bombarded by trackballs

In a thread a few weeks back, Dave Lavery acknowledged that it's pretty likely that the scoring table will be wiped out by a trackball at least once this season, and if I know anything about Dave, I'd say he's secretly looking forward to it. FIRST has known about this from day one, which is why the guardrails are higher than in years past. There are some inherent hazards, but like you said, you can't bubble-wrap everything. It's gonna be a fun season... I'm looking forward to seeing a lot of very creative bots (and maybe a few panicking FTAs).

[Qbranch]

If FIRST was really worried about flying trackballs (I think they should be too) then they should have put walls on both sides of the field as opposed to just the low fences.

I think some shooters may be more unsafe than others (huge spring tensions, etc.) but, overall, it's an important part of the game. Shooters can do something placers can't: hurdle while continuing forward motion, and forward motion is an integral part of this year's game.

Woody1458: Do you have a shooter on your robot?

-q

[GaryVoshol]

Originally Posted by Qbranch

If FIRST was really worried about flying trackballs (I think they should be too) then they should have put walls on both sides of the field as opposed to just the low fences.

They did. From page 4 of "The Arena" manual:

Along the edge of the TRACK between the gates, a set
of additional rails extends upwards from the floor to approximately six feet high. These additional
rails are to help prevent TRACKBALLS from exiting the TRACK during game play.

[danshaffer]

Originally Posted by GaryVoshol

They did. From page 4 of "The Arena" manual:

still, if your shooter is designed to get the ball 6'6" high, it probably should be able to clear 6' walls... why not 10' walls? oh well, teams will probably have to work on their aim...

[=Martin=Taylor=]

You obviously haven't seen our elevator. It could kill a man...

Whenever you move heavy objects quickly things get dangerous. It doesn't matter if you are using an arm or a catapult.

[pakratt1991]

I agree with the dangers point, but i also believe that that GDC will not make a rule to screw over a large amount of teams.

Dad1279 There are only 4 balls in play. I would imagine that the refs(or spotters), probably 2 per side, could easily keep track of and stop or deflect the out of bounds balls.

I saw a picture of team 1501 ( I think ) hurlding a track ball and it made it about 5 feet over the overpass, that's about 12.5 feet from the center of the ball to the ground....
That could get pretty hard to block the balls if they head out of bounds.

[Tom Bottiglieri]

If team update #5 had not been published, I may see your point. But it was published and many safety measures were outlined, so I am not too worried about this issue.

A robot with an arm 9' in the air tipping over can cause just as much damage as a flying TrackBall.

[JesseK]

Originally Posted by Dad1279

There are only 4 balls in play. I would imagine that the refs(or spotters), probably 2 per side, could easily keep track of and stop or deflect the out of bounds balls.

Probably the best idea is to have the field reset crew on duty for it.

Originally Posted by ALIBI

We would love to be able to add a pressure switch, second back up battery and a flashing red light, strob, LEDS, or whatever on a totaly independent circut to indicate when we are armed. The current rules do not allow us to do that. Even better would be if we were able to draw directly off the main battery (for teams with possible weight issues). By doing this, while the field is being reset, everyone will know we are armed. I can just see a well meaning field volunteer grabing the trackball off our robot and having it accidentally fire. Please read my previous post for a further explainatiuon of my concerns.

You probably will not pass inspection if this is the case. If the inspector sees a system on your bot that has no way to slowly release the tension/energy or a way to physcially make it impossible for the system to discharge (even then you never know) then you probably will not pass inspections. For spring catapults, it's been suggested that you have a lock bar that physically disallows the mechanism to release. For pneumatics, you simply would discharge the whole system via the valve. If it's a combo system, well you'll have to figure out something. I'm sure the field reset crew will learn to ask teams to get the balls off/out of their own robots instead of doing it themselves.

Originally Posted by Hachiban VIII

You obviously haven't seen our elevator. It could kill a man...

Whenever you move heavy objects quickly things get dangerous. It doesn't matter if you are using an arm or a catapult.

We call our elevator the guillotine! It takes 3.2 seconds to go up and 2.6 seconds to come down. With the support bars in the back that cross each other during the lift, it's pretty scary -- no one was allowed to stick their hands through at all during the build season.

[ALIBI]

Originally Posted by JesseK

You probably will not pass inspection if this is the case. If the inspector sees a system on your bot that has no way to slowly release the tension/energy or a way to physcially make it impossible for the system to discharge (even then you never know) then you probably will not pass inspections. For spring catapults, it's been suggested that you have a lock bar that physically disallows the mechanism to release. For pneumatics, you simply would discharge the whole system via the valve. If it's a combo system, well you'll have to figure out something. I'm sure the field reset crew will learn to ask teams to get the balls off/out of their own robots instead of doing it themselves.

Currently we have several possible ways to prevent a release. The best would be to launch with ten seconds left in the match with or without a trackball (I know, be careful where we shoot if not making a hurdle). The second is the mechanical stop used for the release, it holds very well, however there is always a chance it could release, it does not require any energy to stay put. The third is a bar that we push through the launcher and other support structures, this must be physically placed by a team member. The fourth is a very slow backdrive on a worm gear, this one has to be deactivated in order for us to launch and may not be practical to use while on the field, again, in the last five seconds we could reactivate it. We have several ways to prevent, slowly or quickly release the energy. I guess we will find out at our first regional if we have done enough.

[Woody1458]

Originally Posted by Qbranch

Woody1458: Do you have a shooter on your robot?
-q

nope. We decided that designing a shooter that could hold the ball well when we wanted it, but throw it well when we wanted it was far too complicated for our machining capabilities. Plus I didn't want to be the team that knocks out the Wildhats mascot with an "accidental" trackball launch

[MrForbes]

Originally Posted by Woody1458

We decided that designing a shooter that could hold the ball well when we wanted it, but throw it well when we wanted it was far too complicated for our machining capabilities.

Interesting....we built ours without ever powering up the milling machine...we used the bandsaw, hacksaw, drill press, some cordless drills, the Rotex round punch, and the rivet guns, plus a lot of files to round off the corners. And almost all our metal stock came from Ace hardware, except the sheet aluminum.

[Woody1458]

Originally Posted by squirrel

Interesting....we built ours without ever powering up the milling machine...we used the bandsaw, hacksaw, drill press, some cordless drills, the Rotex round punch, and the rivet guns, plus a lot of files to round off the corners. And almost all our metal stock came from Ace hardware, except the sheet aluminum.

We dont have a bandsaw, or a punch, and no machining mentors, only a smart dad that can come by once a week, our main mentor is programing only.

[ChuckDickerson]

There seems to be a lot of discussion going on about the safety issues of an errant trackball being shot out of the field. I am more concerned about the damage flying trackballs will cause on the field. Yes, we are supposed to build our machines to “take a licking and keep on ticking” but given the weight constraints we are given, many parts on many robots are not exactly bulletproof. I predict that flying 8 lb trackballs will do some substantial damage to many robots this year and GP or not, feelings are going to get hurt and tempers are going to flare. Think about those arms/lifts/etc up there 10 feet in the air getting hammered by a flying 8 lb 40” ball. I foresee some broken arms/lifts and totally tipped over bots from flying trackballs. I can just imagine the reaction the first time a team has their arm/lift/etc. way up in the air and their alliance PARTNER fires their super-duper trackball trebuchet and nocks over their arm/lift/etc. partner and/or destroys their arm/lift/etc and blocks the whole lane thus incurring a pile of penalties for damage, impeding, etc. and then not only loosing the match but ruining their alliance partners robot. Don’t get me wrong, I love the shooter designs I am seeing, I just wish FIRST had put some sort of limit on the shooter velocity as in 2006.

[MrForbes]

Originally Posted by Woody1458

We dont have a bandsaw, or a punch, and no machining mentors, only a smart dad that can come by once a week, our main mentor is programing only.

I guess "far too complicated for our machining capabilities" is a relative statement!

But I still don't think that there is anything special about either a shooter or arm type robot that precludes any team from building either one, if they can figure out the easy way to do it. The designing is the tough part.

[Brandon Holley]

Originally Posted by Woody1458

nope. We decided that designing a shooter that could hold the ball well when we wanted it, but throw it well when we wanted it was far too complicated for our machining capabilities.

I agree with squirrel. This is interesting. A lot of the catapults I've seen can be made fairly easily with hardware store supplies and some not-so-complex tools and machines.