Can anyone fill in the details of the fire that happened at PNW?
These are the types of things we need to be aware of so we can prevent them.
At event herd it was a battery issue but will check
Samsung obviously has been setting a bad example
From the photo and video clip it seems like wire insulation is on fire and may not be the battery. This might be due to over heating and poor insulation. PDP was on, hope there is a log of current usage on their driver station. Hope LRI can post details of their analysis.
What surprised me more was how FTA was leaning over the bot to tilt it, flames have tendency to flare up. Then the fire extinguisher was spraying powder, hope the FTA had turned his face away and was not breathing the powder.
Did team recover back and continued to participate?
Talk about accent lighting
So I heard that that that battery came lose and experienced an inpact on the terminal forcing it inside the battery. This caused a dead short inside the battery and as such most of the fire was contained inside the battery. I hear that none of the other electronics were damaged but a carbon fiber panel delaminated which is being replaced with polly carb and there was some charing on the AL frame. As well as some dry cem got into the gearbox but they should be back on the field today.
The battery was placed in the robot upside down. During the match the negative lead of the battery was compressed into the battery, causing a short inside the battery itself.
The robot itself did not suffer damage due to the quickness of the field staff. Make sure you know where the fire extinguisher it.
The robot was cleaned out, taken apart, put back together, reinspected and sent back to the field.
I hate to be ‘that guy’, but considering most fires on frc robots are due to electrical problems, why would anyone chance grabbing the metal chassis during that event?
No offense to the FTA who acted quickly and decisively to try to save their robot - but I worry about the danger of grabbing a robot that may have a battery shorted to the frame.
Genuinely asking here: How much damage can a 12v battery do to a human?
Speaking of that thread, props to the PNW field staff for dealing with this fire more quickly than the last video of a robot fire that circulated.
“The only way this battery can hurt you is if I hit you on the head with it”
-my physics teacher
One issue I see here that hasn’t been brought up is the use of an ABC fire extinguisher. This really is not the right tool for the job. A C02 fire extinguisher would be much more appropriate. There’s a few applicable sayings:
“If the fire didn’t destroy it, the ABC extinguisher will.”
“Never point an ABC fire extinguisher at anything you aren’t prepared to completely destroy.”
The dry powder chemical in ABC extinguishers is very fine, very nasty stuff. It is corrosive to aluminum, paint, and other materials, and finds its way into every nook and cranny, making for an absolute cleanup nightmare. And not to mention, you don’t want to breathe it either.
I would never expect for one of our robots to ever catch fire, because we build them to high standards, and we properly crimp, torque, and insulate our electrical connections. However, if it ever did catch fire, I would not be too happy if an over-zealous volunteer emptied an ABC extinguisher into our multi-thousand dollar creation. I will say that the person with the extinguisher here did show some restraint, and didn’t go too crazy with it, and he probably did not have a C02 extinguisher at his disposal.
So the question is, are C02 extinguishers a norm at field-side, and if not, why not? It seems like it would be a good idea for one to travel with every field setup.
I’ll admit most of our fires start as electrical fires, but there’s a fair bit of other stuff that could get rapidly involved. I don’t think we’ve had a bumper fire, but it probably wouldn’t be pretty.
This, +1000. There was a C02 extinguisher at the Michigan State Championships last year when a robot caught fire, but I think I read that the pin broke, rendering it inoperable. A clean agent extinguisher would also be a good alternative to the dry chemical.
If there was a dead short the robot would have immediately shut off, That robot is still hot and live! It was not a dead short but whatever it was is very nasty business. I am very surprised that the bumpers did not go up with the robot though.
I am still waiting on the full report but prelims have pointed at the carbon fiber belly pan as being the conductive agent in starting the damage. More info will arrive later.