Accepted Tethers

Now that the first week of regionals have started, what has been allowed for tethers. How large, rigid, etc.?

Just about everything at KSC was excepted. Most teams with tethers did not use them during practice. During practice, teams have the time to try and get entangled. In matches though, most robots are in a zone camping out. With no robots running around the devices work well. More than 2 teams at KSC have mini-bots attached to a wire and they are OK.

Thanks for the info. Looks like we overengineered our tether then.

A team was DQ’d for entanglement as a result of the tether gettinh pushed under the goal.

Also: there were several DQ’s as a result of robot parts going under the goal.

Everything seemed acceptable at KSC, even things that posed a blatanly obvious entanglement risk. The proliferation of lightweight mouse bots however gives me ideas. It seems a good strategy would be to obduct their tethered bot and carry it back with you. The worst that can happen is they get dq’d for entanglement (not that the things are legal in the first place).

After a lot of back and forth with the FRC Engineers and being told specifically that we could not use a tape measure for an extendomechanism (Jan 25th) we went back and made a segmented foldout arm which did the same job with three times the weight. We already had a mechanism built and ready to go by the time we were told “NO” in the update.

It was a bit disconcerting seeing nearly identical tape devices appearing at both of the regionals today and being used without penalty.

The eight pounds which went into our arm would have been used elsewhere and would have made making 130 lbs. easier. I guess the engineers didn’t pass the word on to the judges.

A suggestion for next year- spell out the design limitations clearly and concisely in the original rule book. If there are loopholes then so be it- that’s the game. But don’t make decisions “on the fly” and expect teams which have already developed designs to change after several weeks. If originality is the name of this game then “pressing the envelope” should be encouraged.,not pigeonholed.

Hey- its a game! We are ready to go. Nice to know anything goes with the send back devices. We were still a bit worried!



Good points.

It is troubling that these previous entanglement risks are now being allowed. I know of a few teams (like yours) who spent weeks designing systems which were not entaglement hazards, and now their work is somewhat wasted since they could’ve done something simpler.

FIRST really needs to come out with a clarification on this… not only for the teams, but also to get all of their referees on the same page.

Andy B.

Speaking for the VCU side of things, FIRST was wishy-washy up to the last second. During the operator meeting on Thursday morning, FIRST said that they were going to be strict on the ruling with tethers. Even if an opponent pushed a goal onto your tether, you would still be DQ’ed for being under a goal. Anything that could entangle, no matter when it was deployed, would be cancelled out. This was of no surprise to our team for this is basically what FIRST has been saying all along.

Friday morning comes and then it is announced that anything that passed inspection is legal and that as long as you didn’t intentionally go under a goal you were fine. There were many toe-touchers out there that were entanglement issues but apparently will be allowed in the future as long as no one actually gets entangled.

Which way is it going to be? :confused:

~Tom Fairchild~

There was much discussion about this topic on FRC’s Yahoo! site and on these forums.

I have to say we are exactly where we didn’t want to be: Those who have tethered devices are being given side-ways glances and those who don’t have them are left thinking, 'I could have designed in one of those if I knew they were legal."

Worse yet, those who read the rules and try to follow them are penalized.

Is this the message that FIRST wants us to take away from all this?

Curiouser and curiouser…

Joe J.

Nothing is worse then seeing all your great ideas out on the field, which your own team threw out because they violated the entanglement rule. We barely got our own extender, a rigid spring loaded arm, which we struggled to get under weight, built, only to see robots with flimsy cables and small little “mouse” bots out there. An attempt by me to move with our extender out severly bent it, and I couldnt help but think if we had just ignored the rules our extender would be lighter, faster, and easier. Either way I’m proud to say our extender arm works and there can be no question to its legality. FIRST competitions arent supposed to be about sneaking by in gray areas in the rules. If you know your tether was most likely against the rules, why would you build it?

We played both sides of the fence on this one.

We designed and built one, but we were prepared to remove it during inspection if it was deemed a violation.

At VCU there was one team with a tape measure device. Since it was almost identical to the one we had built and then discarded, I was curious as to how this team had gotten it past the judges. The team leader said that the judge told him that as long as the numbers were facing down, then it really wasn’t a tape measure and was therefore legal. To make matters worse, the team leader said that the tape measure from Small Parts was not good enough for their needs so they went and purchased theirs from Home Depot. This is a violation of the rules, but the judges never caught it.

I understand that entanglement is a gray area, but when FIRST comes out and issues a ban on a certain type of mechanism and then allows it at the last minute it really penalizes those teams who strictly follow the rules. Our tape measure device was 3-4 lbs lighter than the mechanism we ended up building. And we really needed that 3-4 lbs.

*Originally posted by jasoni *
**We designed and built one, but we were prepared to remove it during inspection if it was deemed a violation. **

This was our attitude as well.

Those teams that were bold, and decided to build a steerable runner well knew that they were treading on a grey area. Our team had even considered building several options, in case one or more was disallowed.

In the end, though, we decided to give it a try, and put our faith in the rulemakers. Because the ruling allowing tethers is the right ruling. By allowing tethers the way they are, they are treating them like any other part of the robot, and that is the correct way to do it.

At VCU rulings for being under the goal were very inconsistant. It did not matter if you went under the goal during the match. It was only deemed a disqualification if you were under the goal at the end.


I think that in the end everything concerning entanglement and DQs is up to the judges anyways. We can just hope that no team will use the freedom that the new ruling gave us to entangle something without being punished. I myself can’t imagine that anyone should voilate the rules and the ethics; as far as I have seen all teams are very cooperative and do not want or need to take advantage out of unfair or fuzzy methods.

I know FIRST’s rulings are really inconsistent about a tether device. And a lot of the calling ended up judgment calls made by judges at each of the two regional, causing different ruling at each place. This unclear ruling from FIRST really caused a lot of unnecessary trouble for teams, and made it not fair for teams who followed the rules strictly and ended up developing something really complicated, or not using one at all.

So, instead of keep saying how bad this is, I think we got to suggest to FIRST what kind of ruling they SHOULD make a competition.

Here is what I think:

The send home device should be limited by the kit of parts/additional hardware list/small parts rule, so that they are made out of legal material. It should also follow the other rules such as damaging carpets/playing field, the spring rule, no projectile rule, and leaving parts on the playing field detached from the robot… And of course the robot has to fit inside the box and weight within 130 lbs.

Then, as for game violations, it should be limited by the no going under the goals rule, no actual entanglement, and no intentionally damaging other robots’ parts rule. Simple as that. And, as long as you are not intentionally violating the rule, such as another team moving the goal on top of your extension, then it should be allowed.

I think this is the easiest way to call it from now on. A lot of teams’ efforts were already wasted when they were told they can’t use this or that, so, let’s make it clear and not waste anymore teams’ effort.

A lot of send home devices were results of great creativity and engineering, and teams worked really hard to come up with this to score points inside the game. They probably learned a lot about designing… I would even say that the send home device is as challenging as some other part of the robot. So, I don’t think FIRST should disallowed such devices. After all, isn’t creativity and ingenuity some of the points of this competition?

Call out the obvious illegal devices, and go back to the nice and generous FIRST Dean told us when they were explaining how a robot can score home zone 10 points just by touching the zone’s carpet.

At the Buckeye Regional the judges also allowed a tape measure to be used as a go-home device. I did notice that the numbers were on the bottom side. My opinion is that is was still TAPE MEASURE! :mad:
After the kick-off I mentioned using a tape measure. I was told it would be an entanglement issue. Even the engineers on YAHOO said so.
Our Tongue and Tail (TNT) weigh 11 lbs each. Think of the weight savings we could have had if I didn’t get voted down.

throws $.02 into kitty

Wayne Doenges

We are a team that prides ourselves on following the rules. Integrity is doing the right thing even when noone is watching. After seeing all the tethers out on the field, we were disappointed.

BUT…this seems to be a de facto rule change, and we will work on designing one of our own between regionals. Ours probably would not violate the more stringent entanglement rules, but I would not look down on any team that sees all the loose tethers on the field and feels a competitive need to duplicate them.

Any thoughts on this?


it makes me sick to see how much this is becoming a problem this year. Seems like it would have been a heckuva lot easier if FIRST just disallowed tether devices all together. This is coming from a team who spent hours agonizing over what sort of device would not be called an entanglement hazard, only to see the very ideas we nixed in our design meetings being used in competition without the judges even questioning! Anywho, our device might not even be on the robot when it comes to inspection, if we can’t get a couple more pounds off :rolleyes:. But i am looking forward very much to seeing how tethers get treated at nationals.
See y’all then

In Message 114 from the FRCtech2002

Tape measure tape, while less likely to be caught on a sharp edge than an piece of string, is still a relatively flexible material when used in long lengths, and might easily be run over and snagged by another robot or a goal that is being moved.

In Message 561 from the FRCtech2002

A) A tape measure or similar device would violate the entanglement rule. FIRSTsnow

It’s bad enough that FIRST is allowing people to actually use tapemeasure tape, but FIRST inspectors are allowing much more flexible tethers than tape measure tape.

To say the least I am very disappointed is how FIRST has and is handling this issue.

If a team wants to follow the rules completely, should should they go and build a tether from a tape measure, since it has been allowed at some competitions, or should they stick to the FRCtech2002 ruling?