# Launch vs Drop Rule G09

Rule G09 states the limitations for launching a POWER CUBE, but is a robot that drops (not launches) a POWER CUBE into the SWITCH if the ROBOT BUMPERS are not in contact with the SWITCH in violation of this rule?

In other words, the robot stops short of the switch by 3 inches and opens it’s claw to allow the cube to fall into the switch. Will this be a penalty?

I searched for similar questions both on CD and on the Q&A and found nothing. I apologize if this has been answered already and if it has, thank you in advance for pointing me in the proper direction to get it.

Check out the other questions about G09 where they ask the GDC to define launching. IIRC, launching does involve force from the robot, which means dropping is not launching. (Q&A does not work from my current location.)

Ok thanks. Looking at the Q&A I searched “G09” and this is the closest question I found:

Q53 In rule G09, what is the definition of launching? Does this mean when a power cube separates from the robot, it is moving in an upward trajectory? Or does launching refer to any and all releasing of a power cube by a robot?

There is no FIRST Robotics Competition specific definition of launching. Per the Blue Box below G22, examples of launching could be “shooting POWER CUBES into the air, kicking across the floor, or throwing in a forceful way”.

So, my interpretation of that answer is I can drop it as long as I don’t have forward trajectory of the cube while doing so or it could be I can “open a claw” while driving forward and the momentum of the cube going forward is okay since it is not “forcefully thrown”.

Thoughts?

That’s the one I was thinking of.

• Dropping it while stopped is certainly not launching.
• Dropping it while essentially stopped (e.g. near the stationary point in a reversal process) is almost certainly not launching.
• Dropping it while driving full speed as you hit the brakes probably is.

If you ask Q&A about whether dropping while driving is launching, I’d fully expect them to leave it to the referee’s discretion as to whether you were moving fast enough to constitute launching.

“Launching” requires you to apply a force to the CUBE. If you just release your hold and gravity moves the CUBE, you are not applying any force and are compliant with G09. At anything other than stopped you will be applying a force to the CUBE and subject, as GeeTwo mentions, to REFs judgement call. Q148 comes closest to addressing your issue and they have stated that they will not provide any velocity spec for the definition of launching.

Plan on being stopped or nearly stopped when releasing the CUBE.

I expect to see many cubes scored something like this: https://youtu.be/US6aAGFwDKc?t=40s (watch the 2 cubes scored by Everybot, in the lower right)

I really hope something like this does not result in a tech foul.

So is it considered launching if its a slow speed? Currently my team is planning to reverse our wheels so that it drops but only falls a few inches forward in comparison.

That is my worry too. Lots of teams (at least ours is) are planning to not wait to let go of the cube to be as efficient as possible. But getting a tech foul is not an option…

We are participating week 1 so I guess we will find out then!

Technically, if you release the POWER CUBE above a PLATE of the SCALE or SWITCH, your manipulator is further away from the Earth’s center of mass and traveling at a different tangential velocity than the PLATE. With a very rigid interpretation of the rules, it would be impossible to deliver a POWER CUBE to a PLATE without launching it.

If First is in doubt about launching vs. dropping or placing…perhaps they need to go back to the old 2006 Ball velocity rule. Lets hope not. BTW was there ever any instance of them actually checking that at regionals or during inspections that year?

Unless I am mixing up seasons I seem to remember an 80/20 rig with some photo gates that measured ball velocity at our event. Back when “shooting” was a novelty.

Or when Caprisun (7456 on bumpers) loses the Cube at 1:04. In this instance, they ware not facing the switch but they could have been.

The velocity of our poof balls was checked at our events that year.
Mark of AndyMark checked ours at the Hartford Regional and we got him to sign our AM gearboxes.

I believe they leave some of these rules ambiguous on purpose.

The intent here is no launching. That SHOULD be the end of the story.

However, as soon as they come out with a strict definition, the community will find some way to break it. It’s what we do, unfortunately for better and worse. We take a rule that should be fairly straightforward and twist it all up into knots.

Leaving a rule up to the ref is one tool the comity can use to say back off.
Are you going to risk using only one strategy dependent on different refs all agreeing not to call a tech?

MOST of the time, common sense should lead the way. (i.e. dropping vs launching)
If an individual ref IS calling a drop as a launch, then adapt. They are likely calling the same for everyone in that event.

I don’t think I agree with you. While I also object to extreme “lawyering” I am firmly in the camp of paragraph 2 of section 1.5. If there is not a rule or restriction forbidding it, it is legal. We certainly look for loopholes, and choke points and are quite willing to design and/or play to exploit them. The only proviso we put on looking for loopholes is that the obvious ones are likely to be closed, so we are not willing to base a design and game strategy soley on it.

They also specifically allow “launching” under some conditions and forbid it under others. Given that, getting a better definition of launching is fair game. Based on what I have seen so far, the GDC’s definition of launching is your robot applying force to the CUBE. So far they have not clarified where the go/no go cutoff point is, in terms of how much force.

There is no “common sense” called out or expected in the manual. If your robot and actions on the field are within the spec (the game & season manual) then you are good to go.

I do agree that the GDC leaves themselves some wiggle room by falling back to the “ref on the field will decide” answer in some cases.

In the instance of the everybot though isn’t it in one of the few positions that you could launch from anyway?

It seems to me the Everybot is just short of touching the wall of the switch when it “launches” the cube.

Judgement calls are tough for FRC. I am very curious how it will be called

You could be driving east just fast enough to compensate… for every foot of excess altitude of the cube, you’d need to be driving 2πcosλ ft/day. At Bayou (latitude 30 degrees) for a 1 foot drop, that would be ~6.3x10-5ft/s. I wonder how many refs would notice…

Edit: for Santa Fe (Mexico) Regional, that speed would be a blistering ~6.9x10-5ft/s, and at Canadian Rockies a stately ~4.6x10-5ft/s.