Dry Ice as Motor Coolant

[4373Henry]

Would it be permissible to have a small pouch of crushed dry ice next to one of the motors? We have been having some issues with a motor overheating. It would be completely enclosed in a cloth pouch and the amount would not exceed about 5 grams.

[MrForbes]

My guess it that it would be considered unsafe, so it would violate rule R8. There is danger of frostbite, etc.

But the Q&A would be the place to get an official answer.

[MrRoboSteve]

Alternatives:

heat sink for motor (http://store.nextgenrobots.com/)

put fan on motor (check rules before selecting fan)

bigger motor with more mass

make your mechanism more efficient

[4373Henry]

My guess it that it would be considered unsafe, so it would violate rule R8. There is danger of frostbite, etc.

But the Q&A would be the place to get an official answer.

But isn't mild tissue damage from prolonged contact with dry ice is a lot better than most other robot related injuries?

[MrForbes]

Reducing the risk of all robot injuries is better yet, eh?

[Ozuru]

I think MrForbes is right -- that would be very hard to pass inspection with. I have a feeling you'd need to fight it at every competition.

[The_ShamWOW88]

Isn't mild tissue damage still tissue damage?

Ask the Q&A...better to have an official answer

[Munchskull]

I feel that the sublimation would occur too quickly for it to be an viable method of cooling during a match. a quick cooling in your pits might work though. If this is a CIM motor try looking into a cim heatsink. May I ask what you are doing to overheat this motor?

[Ether]

We have been having some issues with a motor overheating.

May I ask what you are doing to overheat this motor?

Yes, please give some details.

It seems quite a few teams this season have missed the boat on gear ratios. Or are trying to use motors to hold heavy loads.

[hardcopi]

We had a problem with overheating too and the heat sinks fixed it up pretty good. That was after 3 hours of solid driving though (driver try-outs) so I don't expect any issues. Still the heat sinks work really well.

[rich2202]

There was a Q&A about fog machine that could be relevant.

There is also an issue of Robot Weight. How is an RI to know that you weighed with 1 pound of dry ice, but now have 2 pounds on your robot?

Finally, if any smoke does come from your robot, even if it is white, you are asking to be disabled.

[philso]

We have been having some issues with a motor overheating.

How hot is the case of your motor getting? Measure it and ask the vendor if the temperature you are seeing is acceptable. Some of the legal motors normally run pretty hot. You might actually be Okay.

[Scott Kozutsky]

I agree that you should make sure that the motor isn't actually overheating.

If it is, the solution that many teams use (254 and 1114 on Einstein for example) is getting the compressed air dusters and flipping them upside down and spraying them at the motors between every match.

I recognize that this does not answer the question of whether it's legal to have dry ice but this may be an easier solution anyways.

[alicen]

Would it be permissible to have a small pouch of crushed dry ice next to one of the motors? We have been having some issues with a motor overheating. It would be completely enclosed in a cloth pouch and the amount would not exceed about 5 grams.

As a robot inspector, if you were at any of the regionals I will be inspecting, I would not let this pass inspection.

It's dangerous, technically a hazardous material, and has potential for leakage or spilling, thus causing damage to the field or other robots.

Please look into some of the solutions that other people have been posting, they are much more reasonable and will allow you to pass inspection :)

[techhelpbb]

Probably can't stop you from using fully melted dry ice in no container :D
Doesn't really help with the motor overheating.

[Ether]

Probably can't stop you from using fully melted dry ice in no container :D

Physics will stop you from storing "fully melted" (liquid) CO2 in no container.

[techhelpbb]

Physics will stop you from storing "fully melted" (liquid) CO2 in no container.




Technicality ;)

[GeeTwo]

ROBOTS may not intentionally detach or leave parts on the FIELD.
As I recall, the field is a volume, not a surface, so venting carbon dioxide to the atmosphere would violate G25 as well.

[seg9585]

As I recall, the field is a volume, not a surface, so venting carbon dioxide to the atmosphere would violate G25 as well.

Hah. In that case, wouldn't an infinitesimal amount of pneumatics accumulator leakage also break the same rule? We will need to reference the Maxwell-Boltzmann distribution equations to know how quickly G25 becomes violated.

[BBray_T1296]

It's dangerous, technically a hazardous material, and has potential for leakage or spilling, thus causing damage to the field or other robots.

I understand the whole argument that dry ice could be considered a hazard to humans, but out of curiosity I am interested in how you think any amount of dry ice (let's be reasonable) could cause damage to the field or other robots.

I feel like dumping air from the pneumatic system is more dangerous to a robot simply from the moisture condensate in the tanks


By the way, at any standard temperature for a robotics venue, dry ice does not melt, but sublimes

[Kevin Sevcik]

Poorly secured dry ice on a robot would be a hazard if the robot tipped. Plus you're going to confuse field staff with your "smoking" motor. Plus thermal stresses like that aren't good for a motor. Plus condensation. I'll pile on with everyone else and ask what you're doing to this motor that's making it so hot.

[Ether]

at any standard temperature for a robotics venue, dry ice does not melt, but sublimes

CO2 cannot exist as a liquid below 75 psi pressure, regardless of temperature.

Also, CO2 cannot exist as a true liquid above approx 31 degrees C, regardless of pressure.

[josephus]

Additionally, if you start a match with five grams of a substance and you end the match with five grams less than you started with, are you leaving materials on the field?

[Ether]

are you leaving materials on the field?

...because CO2 is heavier than air?

[matthewdenny]

I would think the "leaving it on the field" argument people are making here would apply to pre pressurized pneumatics as well? Technically your robot would have less mass if the pneumatics was lower pressure at the end.

[who716]

we have specially made aluminum that we place on the motors in between matches and the heat from the motors transfers right over to heat the aluminum