Team Update #18

[Chris is me]

Originally Posted by Karthik

Be careful to paint both teams with the same brush stroke. Mark made a specific description of 190's deployment which made Paul think it's illegal, namely the creation of potential energy by the downward movement along the track. From my understanding, Pink's ramp only goes upward, meaning the track (and thus the hostbot) would not be contributing any energy.

Good point.

For what it's worth, 190's track begins horizontally like 233's track - the minibot is the sole source of energy.

One could make an argument that the robot converts the horizonal motion of the minibot into vertical motion, but that's a bit of a shaky justification.

[Chris Hibner]

An update from Detroit:

All of our minibot runs triggered the tower. Everyone that I saw triggered the tower except one:308's minibot failed to trigger once and it cost them the match. I'm not sure if it hit the bolts, but it hit the plate with more than adequate force. They have a very reliable minibot that triggered every other time they ran it.

I think I may have saw one false trigger, but I can't confirm.

[Chris Hibner]

Originally Posted by Chris is me

Good point.

For what it's worth, 190's track begins horizontally like 233's track - the minibot is the sole source of energy.

One could make an argument that the robot converts the horizonal motion of the minibot into vertical motion, but that's a bit of a shaky justification.

I would say that if the track is horizontal and fully below the deployment line it is legal. However, if it starts above the deployment line, uses gravity to gain momentum, then deploys below the line, I would say it is illegal because it used potential energy to impart vertical motion.

[Ian Curtis]

Originally Posted by Karthik

Be careful to paint both teams with the same brush stroke. Mark made a specific description of 190's deployment which made Paul think it's illegal, namely the creation of potential energy by the downward movement along the track. From my understanding, Pink's ramp only goes upward, meaning the track (and thus the hostbot) would not be contributing any energy.

As a devil's advocate, I'm still not sure even that is legal. <G19> specifically says "...solely through electric energy provided after the start of DEPLOYMENT by the permitted..." As the 190 design has the robot accelerating through electrical energy prior to deployment (crossing the plane of the base) I could see the argument that they are storing "non-incidental" kinetic energy in their minibot. Probably the only way to get the real answer is the Q&A. Does 233 start their minibot within the base? I'm pretty sure 190's did not.

It wouldn't be an FRC game if 190 didn't do something that CD could argue the legality of for entirely too many posts!

[jspatz1]

Originally Posted by sanddrag

But how much did your minibot weigh during this test, which found this diameter to be optimal?

In this case, 2 lb. 9 oz.

[boomergeek]

Originally Posted by Chris Hibner

I would say that if the track is horizontal and fully below the deployment line it is legal. However, if it starts above the deployment line, uses gravity to gain momentum, then deploys below the line, I would say it is illegal because it used potential energy to impart vertical motion.

I see it slightly differently:
The track PRIOR to the DEPLOYMENT cylinder needs to be horizontal (or upward) and should not be longer than the length of the minibot (plus a grace distance of couple inches). Long horizontal tracks spanning the HOSTBOT would violate <G19>.

The shape of the ramp within the deployment cylinder can be any shape because the shape does not create additional energy.

If a team uses a ramp, the HOSTBOT must remain perfectly stationary while the MINIBOT is moving on the RAMP, otherwise it is not clear if the HOSTBOT is adding energy to the MINIBOT.

[jspatz1]

Seems to me that "...solely through electric energy provided after the start of DEPLOYMENT..." is pretty darn unequivical. No other form of propulsion energy can be used, even if it is the robot's own potential energy. Just because acceleration from gravity is free does not mean it is allowed. This would certainly qualify as energy other than electric energy, and if I understand the description, would also be partially gained before deployment (before crossing the cylinder of the platform.) This is one of those cases where you are just going to have to live with the "spirit of the rule."

[kstl99]

Anyone know of a video for the 190 or 233 deployment system in action?

[jspatz1]

Originally Posted by boomergeek

The shape of the ramp within the deployment cylinder can be any shape because the shape does not create additional energy.

If the ramp shape causes a net elevation drop in the minibot before it reaches the pole, then additional energy other than "electrical energy from the motors" (in this case the minibot's own potential energy due to gravity) has indeed been imparted on the minibot.

[MrForbes]

I haven't heard of any problems at AZ. Our minibot did not trigger the second time we deployed...but we did find our charger, and we think it will make it further up the pole next time.

[boomergeek]

Originally Posted by jspatz1

If the ramp shape causes a net elevation drop in the minibot before it reaches the pole, then additional energy other than "electrical energy from the motors" (in this case the minibot's own potential energy due to gravity) has indeed been imparted on the minibot.

...move up the POST solely through electric energy provided after the start of DEPLOYMENT by the permitted, unaltered battery and converted to mechanical energy by the permitted unaltered motors...

As long as gravitational potential lost plus gravitational potential gained is zero or negative below the deployment line- it provides NO ENERGY "to move up the POST". All energy is coming from the batteries/motors- but the allowed advantage for the rampbot is that its battery/motors energy expended as soon as it crosses into the deployment cylinder can be transferred through any shape ramp into vertical motion up the pole.

[R1ffSurf3r]

Originally Posted by Ian Curtis

Does 233 start their minibot within the base?

yes

[jspatz1]

Originally Posted by boomergeek

...move up the POST solely through electric energy provided after the start of DEPLOYMENT by the permitted, unaltered battery and converted to mechanical energy by the permitted unaltered motors...

As long as gravitational potential lost plus gravitational potential gained is zero or negative below the deployment line- it provides NO ENERGY "to move up the POST". All energy is coming from the batteries/motors- but the allowed advantage for the rampbot is that its battery/motors energy expended as soon as it crosses into the deployment cylinder can be transferred through any shape ramp into vertical motion up the pole.

I envisioned from some of the descriptions a ramp with a net downward slope that allowed the bot to gain momentum from elevation change. If instead you are saying that the minibot gains momentum between the deployment cylinder and the pole by simply using its own motors to get a "head start" and then the track directs this momentum upward, then I would say that is legal, and a clever idea.

[Al Skierkiewicz]

Originally Posted by martin417

Peachtree update:
It looks like, for peachtree at least, all this worry was for naught.

Seems I have heard that somewhere before...

As for the 190 design, if the curved pipe does not contact the tower above the 18" mark there is no violation there. The minibot is using the electric energy stored in it's legal battery to drive so no violation there. The GDC has ruled that the motors on the minibot can be running prior to deployment so there is no violation there. However, G19 may apply if it can be proven that gravity is actually adding to the minibot's ability to climb the pole. I cannot see that a downward movement on a pipe adds anything to the upward motion of the minibot. What goes down does have to come back up afterall.
<G19> MINIBOTS must remain completely autonomous and move up the POST solely through electric energy provided after the start of DEPLOYMENT by the permitted, unaltered battery and converted to mechanical energy by the permitted unaltered motors (and associated, appropriate circuitry). Violation: The TOWER on which the MINIBOT is DEPLOYED is disabled. If the MINIBOT is DEPLOYED on something other than a TOWER, then the ALLIANCE’S TOWER upon which the highest RACE SCORE was earned will be discounted.

<G19> means that HOSTBOTS are not allowed to launch the MINIBOT up the pole at the TARGET, or otherwise contribute to the vertical movement of the MINIBOT. Energy for vertical movement may not be stored in the MINIBOT before DEPLOYMENT (except that which is contained within the battery and excluding incidental kinetic energy stored in the motors or wheels, but NOT, for example, in a flywheel).

[Ether]

Originally Posted by Al Skierkiewicz

I cannot see that a downward movement on a pipe adds anything to the upward motion of the minibot.

It could if implemented well.

If the minibot on the host is higher than the deployment line on the tower pole then in theory the difference in height is potential energy that gets converted into kinetic.

It all depends on whether the friction loss traveling the curve pipe is greater than the KE gain due to the added PE.