Anybody let the magic smoke out?
 

Just out of curiosity, has anyone let the magic smoke out of the RC? (I.E. Did you ruin it?) I was thinking about it because yesterday I had smoke come out of wires attached to the RC. :eek: The only reason it didn't kill our controller was the fact that the wire was thin enough it burned through before the the RC was damaged. If you have fried it, or have come close, post and tell me so I don't feel so bad. :)

Re: Anybody let the magic smoke out?
 

On several occasions over the past week, I've had a subliminal impression of smoke somewhere in the robot chassis. So far, it's always turned out to be a blurry reflection of one of the building's overhead fans on a shiny bit of metal. The occasional burning smell in the shop hasn't been from the robot yet either. (What's the smiley for "knock on wood"?)

Re: Anybody let the magic smoke out?
 

We have successfully fried 4 speed controllers and the RC last year (it was our rookie year :)) by trying to weld something on the bot while all the above mentioned electronics still remained connected. The ground wire from the welder fell off and touched a terminal on a speed controller... The explosions were quite spectacular :D

Thankfully, another team lent us their old 883 speed controllers and RC so we could practice until we got new ones for ourselves. I dont remember the team name now :( If it wasnt for that team, we would not be able to compete.

Re: Anybody let the magic smoke out?
 

Not the RC, but we fried a 884 when one of the teammates drilled through the bottom...

Re: Anybody let the magic smoke out?
 

One of our freshmen broke a screw off in an 884, does this count?

Some of the vets on our team got it our with much sweat and blood, though. We have 2x spares. A good thing.

Re: Anybody let the magic smoke out?
 

We messed up the RC pretty bad last year. Were were testing out the robot on tether and only had one half of the ramp up. Drove it up to the top of the ramp, then it accidentally launched itself off the cliff on the other side, tearing the tether port off the RC cause the cable wasn't long enough.

I wasn't there to see it, but I'm sure it was a rather embarrassing thing to have happen.

Re: Anybody let the magic smoke out?
 

Our team tried to keep the robot from 2 years ago intact for practice...didn't quite work. I missed a day when we were taking off the un-needed components, and when i came back someone had managed to fry the RC by means of shorting out a Vic. Not fun :(

Re: Anybody let the magic smoke out?
 

Yup.
Last year:
Aluminum Shavings + Victor terminals = pretty sparks.

Re: Anybody let the magic smoke out?
 

Check back in tomorrow...that's when 818 will hopefully have this year's robot running...

I'm just a programmer, though - any magic smoke is not my fault. Not at all. :)

Re: Anybody let the magic smoke out?
 

What about the magic noise in the mechanical parts?

most people are not aware that mechanical parts are made in machine shops where they are pumped full of noise (which is why machine shops are so loud)

the noise must only be let out of the parts a tiny little bit at a time - if the noise leaks out all at once the parts will fail. once all the noise has escaped from the parts you have to send them back to the machine shop to be pumped full of noise again.

With electrical parts its almost impossible to get the magic smoke back in, but with mechanical parts a skilled machinist can often pump it almost full of noise again.

One last thing, if a mechanical part fails on you, sometimes you can get a little bit of noise back into it by yelling at it, kicking it, or pounding on it with your fist. This might put enough back into it so it will work for a few more minutes.

Re: Anybody let the magic smoke out?
 

During the offseason I let the magic smoke out. I was working on one of the previous years robots and two of the pwm cable ends got together with the power on.......there was lots of smoke. PWM cable ends together= really bad news. The caqbles were melted together and I wasnt able to pull them apart. I let the magic smoke out of lots of things for fun though.......try a 12 ohm resistor at 30 VAC on an educational board so it is safe. Another idea for you teachers and tinkerers: try putting a burned out light bulb in a microwave until it explodes then leave the microwave running and watch the ball lightning come off of it. That wasnt my idea, i thought the robotics mentor/physics teacher was crazy at first for doing it but the result was awesome.

Even though I dont get hurt often I have gotten the reputation for doing crazy stuff in the lab. Its great to scare the juniors here at school by grabbing a hot 120 VAC wire. They get scared that you are going to release magic smoke, its great.

Re: Anybody let the magic smoke out?
 

and this is why we never use the screw-in knobs on the tether cable ;) better to have the tether fall out than to kill the port entirely :)

Re: Anybody let the magic smoke out?
 

Just today I was using a computer power supply for a 5v power source, testing my sensor circuits. I accidentally touched the power and ground lines. Apparently the source isn't fused; immediately it heated up to the point that I couldn't touch it, and black smoke came off the alligator clips that I was using. The plastic sheath over them melted together before I could hit the off switch...

Re: Anybody let the magic smoke out?
 

We were doing speed tests this year, and hit the e-stop button before the robot hit anything. However, this caused the robot to do a front flip, and it landed upsides down after doing a front flip. We bent a couple bins on the RC. However (and thank goodness) we did not destoy it.

Re: Anybody let the magic smoke out?
 

Re: Anybody let the magic smoke out?
 

Don't clicks and snaps from motors-with-rachets-being-driven-backwards release a lot of that noise at once? :)

Re: Anybody let the magic smoke out?
 

I think we fried the Analog Inputs on a controler for GeroniMOE last year. We hooked up hall-effect transistors (magnet actived transitors) with pull up resistors to sense embedded magnets in drive train sprockets. Our hope was to get a good readout of wheel revolutions but we noticed that those transistors and the gyro stopped working. The rest of the controller still worked so we put it on the practice bot (Sitting Bull) which didnt need a gyro.

Re: Anybody let the magic smoke out?
 

We did the same thing with the RS port.:) Fortunately we fixed it.