Release of tetra at match end by referee.

I understand that if a referee is unable to remove a tetra from the robot at the end of the match without powering it on, then the team/alliance will suffer a penalty.

how hard will he try?
would he push a button to close a pneumatic cylinder?
would he pry open a grabbing arm?

would he try at all?


Don’t count on it. While the referees/field attendants MAY make a few attempts to free a tetra from the grasp of a robot, it would only be done if there were an obvious and simple way to do so. But remember that the referees/field attendants will not know your machine. If pushing a button or pulling a lever is required to make your robot release its grasp on the tetra, the referees/field attendants will not know that and they will not know how to actuate the release mechanism. So it is probably not a good idea to go with a design that would require that type of action.


I see… do you think that marking the button with a big blatant sign would help?

i’ll go to the mechanical forum, maybe the valves have a configuration that would trigger them when there is no power…

and another idea would be to have a counter run for 134.5 seconds (2 minutes 14.5 seconds) and when it gets to 134.5 it’ll just trigger the valve automaticly…

Thanks Dave!


At the end of the match, robots and tetras will be left alone until the referees are done scoring the match. Teams will stay out of bounds until the head ref signals them to come on to the field. At that point, if there is a tetra stuck in a robot, the referee most likely will ask the drive team members to remove the tetra. The ref would not be the person to do this.

The key to this situation is to have the robot easily release the tetra. FIRST is concerned about keeping the matches going at a steady, quick cycle. Teams should be able to get their robot off of the field (and remove tetras from their robot) quickly.

(I’ve reffed at a few of these competitions)

Andy B.

and this applies for this year too?

if so, we have no problem, all we need is possibly a small ladder… :slight_smile:


I dont know about the ladder plan… But you might be able to tip your robot to get the tetra. Like Andy said the goal of this rule is not to penalize teams, but rather to make sure that a team does not have to get a toolbox and dissassemble their robot on the field just to retreive a tetra. They try to make the clean up and resetting of the field go as quickly and smoothly as possible.

well, since our regional will only have 4 games (12 teams), i think we’ll have plenty of time :slight_smile:

i’ll talk to the coordinator though… just to get the final ok…

thanks guys!

Either that or you will have lots of matches with each team!

One solution we have used in the past to avoid touching the ramp, touching a ball at the end,etc is to have the program automatically retract the potentially offending subsytem just before the end of the match. This happens despite the operator’s best efforts to prevent it. :smiley:

It really works well with pnuematics as you could program the valve to cycle at say 2:14:30 in the match. The system takes care of the rest. Since it takes a little bit of time for the air to redistribute itself, the actual motion may occur after the buzzer sounds. It was really handy in 03. Though back then the program didn’t have timers built in and I think we did it with counting program cycles. So we timed it to go a little early.

In this case it could result in a premature drop of a tetra you were about to score. But you might do better to just hold the tetra over the goal and allow the pre-programmed release. The tetra could just fall into place and you don’t have to worry about being in contact with it.


But if you want the bonus you won’t have to worry about dropping a tetra prematurely because you’d be in your endzone at the end, unless you want to cap a goal there at the end. That’s an idea. Get the bonus and, if each alliance robot caps at the end, an entire row as well. That could be a viable strategy.