Driving on carpet
 

So my team was driving around on a carpeted part of the shop today and spinning the wheels all over the place for about 5 minutes. When one of the mentors on the team went to go touch the chassis he got a pretty big shock from it. Apparently the plastic has the "wool socks on carpet" effect. Is this something I should be looking out for? I mean...some of the components in the kit came in special bags to protect against static shock, I would hate to ruin all the components on the board because I touched them:( . Anyone else experienced this??

Re: Driving on carpet
 

This also happens when running on REGOLITH. Every time we would go up to the robot we would get a decent static shock. It was much more prominent on carpet though.

Re: Driving on carpet
 

is it something to be worried about? If the cRio and other components are insulated from the chassis does it matter?

Re: Driving on carpet
 

how long were you driving for?

i wouldent want to chance it.......

Re: Driving on carpet
 

I think it was only for 5 minutes, but like I said there was tons of wheel spin (like, donuts the whole time:P )

Re: Driving on carpet
 

Which is totally unavoidable :P

I wonder if something like the vibration dampers on the "feet" of the compressor would help at all? (If it is a problem) It is my understanding that the bolt does not run all the way through the damping system thus making it insulated.

Re: Driving on carpet
 

Oh jeeze. Are you serious?? Did FIRST think about the chance that it might cause static electricity??

Re: Driving on carpet
 

Is it even a problem though if the electronics board is isolated from the chassis?

Re: Driving on carpet
 

I dunno. It shouldn't be, I don't think. Mind you it is my first year doing electrical stuff.

Re: Driving on carpet
 

I can't envision it being any problem. It'll be a shocker if it is.

Re: Driving on carpet
 

Shouldn't be a problem. Our 06 bot turned out to be an unintentional Van De Graph generator, so we could get a HUGE jolt by touching the frame after any match. Lucky we had a crazy freshman who kinda liked it!

Re: Driving on carpet
 

I don't believe it will be a problem either, since most teams mount their electronics on lexan/polycarbonate, no additional precautions are really necessary.

Re: Driving on carpet
 

Traction wheels on carpet generate static electricity too. We've usually put a short grounding strap/chain on our robot when practicing at our facility, just to keep from zapping the students. It sounds like we'll be needing one again this year.

Re: Driving on carpet
 

We have put one on the practice robot and it seems to be working.

Re: Driving on carpet
 

So the wheels are stripping electrons off of the ground and giving the chassis a negative charge while leaving the ground positive. The opposite charges will then attract thus increasing the force of the robot on the regolith. Will this be counted as an extra traction device?:P

Re: Driving on carpet
 

Well if it does, All teams will be illegal for increasing the traction!! Fun game when no one's playing since we're all illegal! haha!

Re: Driving on carpet
 

if my understanding of electricity is correct,

it should be the other way around

Re: Driving on carpet
 

Same for us in 06. Hooray for freshmen!!

Re: Driving on carpet
 

The rule that requires the camera and CRIO be insulated is to prevent interaction between robots that might cause electrical issues since both of these devices have a connection between the case and negative power supply. The static discharge that most teams experience may or may not cause problems with your robot. Teams in the north during winter experience low humidity from the heating during the cold months which makes matters worse. Humidty tends to draw off the charge. Dragging an electrical anchor (wire, braid, etc.) likely does very little since the driving surface (carpet or regolith) is an insulated material. Please be advised that high impedance sensors are the most vulnerable to static discharge but anything on the robot can be affected. We have found that certain electronic potentiometers are overly sensitive to static. If you are using these devices and have an issue during static discharges, I would recommend a change of component design to something more fault tolerant. I would predict that as much static builds up as the insulated wheels are turning near metal robot frame parts as is picked up by the robot moving across carpet.

Re: Driving on carpet
 

Um, I beg to disagree. Touch some electronics (see ASl's post above) and the static discharge will damage it, either 'walking wounded' or outright failure.

The solution is almost trivial though: ALWAYS (always always) touch the metal chassis before touching anything else. This will discharge any static and render it mostly safe.

The "correct" way is to wear a static discharge strap (buy one, don't make one, they have resistors in there...) and connect THAT to the robot metal before doing anything. Straps like that are under $5.

Thise metal foil-like plastic bags? Yep, those are used to protect static-sensitive items in shipping. ANYhting that came in one is sensitive to static and you really, really ought to follow the right procedures.

Don

*Walking wounded: You have damaged a semiconductor in such a way that it will fail very soon, but works OK at the moment.

.

Re: Driving on carpet
 

you guys should all check out and read Team Update #5

its all about the electro-shock concerns and how to deal with it.

http://www.usfirst.org/uploadedFiles...Update%205.pdf

Re: Driving on carpet
 

I don't see what everyone's problem is we've been driving around fine and haven't been shocked at all. We discovered the solution: wooden axles :D We've found balsa wood to be the best choice.

But I do agree just touch the chassis before anything else...or find a freshman to do it for you.

Re: Driving on carpet
 

Walking Wounded...
def. A semiconductor about to give it's life to protect a breaker.