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View Full Version : Things You Shouldn't Do


Ekcrbe
14-02-2012, 10:51
I thought it would be ineresting to see what things people have done that they regret...

Our team accidentally plugged an analog sensor into the digital side of the sidecar...
[magic white smoke]

electron
14-02-2012, 10:58
Things to not do:
-Think you can worry about wire management after everything is wired.
-Put the Digital Sidecar in the most out-of-the-way, hardest-to-reach place on the robot you can possibly imagine. :rolleyes:

Things to do:
-Make sure the jags are not wired backwards.. ::rtm::

SenorZ
14-02-2012, 12:10
Get M+ and V+ mixed up on a jaguar... And turn on the robot

BrandonGlatz
14-02-2012, 14:17
Connect two battery connectors together.... I still regret that to this day...

OZ_341
14-02-2012, 14:22
We had a rookie store bare steel cables in the same crate with an un-insulated battery.
It makes a beautiful green vapor!! :yikes:

Ty Tremblay
14-02-2012, 14:34
We had the robot in the back of an SUV on the way to a practice field. Somehow, a battery fell over and the two leads connected on our drive train. We didn't notice until we got to the field about 30 minutes later. The chain go so hot that several links were welded together.

Moral: Insulate and secure your batteries.

Taylor
14-02-2012, 14:39
While we were helping set up an indoor summer offseason competition, we did not realize it was raining outside. Our robot, however, took note of that. Mostly because it was in the bed of a pickup truck at the time.

LinuxArchitect
14-02-2012, 14:41
Don't assume white dashes on a wire mean negative polarity. Buy two of everything until you figure that out.

scottydoh
14-02-2012, 15:11
While we were helping set up an indoor summer offseason competition, we did not realize it was raining outside. Our robot, however, took note of that. Mostly because it was in the bed of a pickup truck at the time.

That's not always the end though. Out lead teacher is notorious for leaving the robot outside in his truck through all kinds of weather. Back in 2008 the robot sat through a rain storm, several days later we went to use it an a demo and noticed water dripping out of the computer (The old school IFI Microchip one) So we took it apart and dried off the PCB with a hand dryer in the men's room, 15min later the robot was up and running perfectly.

1986titans
14-02-2012, 15:13
This wasn't on my team (it happened at college), but one time a kid was working near a battery much like the FRC ones and managed to put a screwdriver across a couple uninsulated terminals.

Moral: Give thanks for insulated screwdrivers.

giantmidget31
14-02-2012, 17:10
Don't assume white dashes on a wire mean negative polarity. Buy two of everything until you figure that out.

I thought white dashes were always positive...

dellagd
14-02-2012, 17:12
I believe they are :P

He was saying dont assume that, because they arn't :P

nitneylion452
14-02-2012, 18:18
We had someone measure the distance between the terminals of a battery with a measuring tape. He contacted both terminals. Needless to say, the tape measure is no good from ~2 to ~4 inches. Completely burnt. It now sits proudly in our hall of shame, along with some other things.

gyroscopeRaptor
14-02-2012, 19:31
We had someone measure the distance between the terminals of a battery with a measuring tape. He contacted both terminals. Needless to say, the tape measure is no good from ~2 to ~4 inches. Completely burnt. It now sits proudly in our hall of shame, along with some other things.

I would like to see what else is there.

We never do any drilling on a robot with any electrical parts attached unless a vacuum is sucking away chips and swarfs from the drill. Lexan, Wood, Aluminum, Poolnoodles, nothing is drilled unless a vacuum is there.

Once we were using a piece of scrap metal to determine angle on last year's bot's Lexan, and almost contacted bare battery terminals.

cgmv123
14-02-2012, 19:51
I thought white dashes were always positive...

I thought that too. :confused:

Whippet
14-02-2012, 20:29
Never, ever drill a hole in a block of wood unless it is clamped down. Our team captain lost a large part of her finger this way. ::safety::

Trez
14-02-2012, 21:20
Never, ever drill a hole in a block of wood unless it is clamped down. Our team captain lost a large part of her finger this way. ::safety::

Last year we were cutting a piece of plywood on a table saw. The newly cut piece of wood got lodged between the saw blade and the sliding guide and shot 20ft clear across the shop making a large hold in the wall.

nikeairmancurry
14-02-2012, 21:52
Last year we were cutting a piece of plywood on a table saw. The newly cut piece of wood got lodged between the saw blade and the sliding guide and shot 20ft clear across the shop making a large hold in the wall.

Lexan + same set-up + me standong there = Ouch

krazyman1013
14-02-2012, 23:41
Make sure everything on the CNC work tray is clamped down or the material will spin on the bit at approximately 2500 RPM until the bit breaks.

Nate Laverdure
15-02-2012, 08:12
Last year we were cutting a piece of plywood on a table saw. The newly cut piece of wood got lodged between the saw blade and the sliding guide and shot 20ft clear across the shop making a large hold in the wall.
That's called kickback, and it's one reason why the table saw is probably the most dangerous tool in your shop. Please be careful!

MichaelBick
15-02-2012, 08:39
Don't use bad PWMs. Also, don't connect PWMs backwards.

patrickr41
15-02-2012, 08:50
never trust the robot when its on
we lost connection with it and it went after the whole team
robot+lose connection=sprang ankle and no more camera turret :(
don't forget when your working on it to put it on blocks......::ouch::

MechEng83
15-02-2012, 09:19
Neophyte team member sent to deburr a hole in a plate... 30 seconds later, we hear a loud sound and I spend the next 30 minutes extricating said plate from deep within the belt sander...

Walter Deitzler
15-02-2012, 09:57
DO NOT! go up to your team's CAD computer and decide it would be funny to mess around with the design. While fixable with 'undo' or 'ctrl z', it is really annoying and not remotely funny. One time a rookie even accidentally caused the computer to freeze up, making me have to re-CAD everything I had been working on

Do: Constantly save your CAD drawings

bardd
15-02-2012, 12:15
This happened to us a week ago. If you need to drill holes in a plate, and the holes are right above an encoder, NEVER EVER drill them without removing the plate!!!

That encoder took too long to replace :(

treffk
15-02-2012, 12:22
Do not try to see if the battery fits and accidentily touch the battery terminals to the frame causing sparks and the unfortunate nickname of Sparky.

Also do not forget to put the tailgate up on the truck you are hauling the robot in. You will make a turn and the robot will fall out on the highway.

caltemus
15-02-2012, 17:17
Do: Insulate your batteries the INSTANT you get them. I thought everybody did that...

dudefise
15-02-2012, 18:26
We had a 2-cim shooter setup, and wired the positive wires from each motor to one jaguar, and the negative wires to another! Thankfully, the jags survived and seem to have avoided any damage.

Ekcrbe
15-02-2012, 19:34
Things to not do:
-Think you can worry about wire management after everything is wired.
-Put the Digital Sidecar in the most out-of-the-way, hardest-to-reach place on the robot you can possibly imagine. :rolleyes:

Things to do:
-Make sure the jags are not wired backwards.. ::rtm::
We actually did a similar thing, putting power into both sides of a Jaguar, and found that it was unresponsive afterward.

ianonavy
16-02-2012, 08:10
Don't wire motors directly into the power distribution board and turn the robot on.

PayneTrain
16-02-2012, 09:09
Don't let freshmen drill on your electronics board by hanging it over the table when you aren't looking, causing a giant crack to form in the Lexan you and your squad spent hours working on making the biggest, best board we ever made... in Week 6.

Why me.

Anupam Goli
16-02-2012, 09:34
Never ever EVER let the mechanical engineer guys design places for electronics to go and wires to go. They will put it under a giant rotating arm and make it impossible to wire anything there. Always design it yourself or find a place and be firm about it.

DavidB96
16-02-2012, 09:47
i put a wire connected to a bettery, much smoke. then a friend did it to prove what happened, and he got in trouble for it!:yikes:

rsisk
16-02-2012, 09:50
Never forget to secure the robot crate in the back of a pickup when driving. It will fly out of the truck.

Nothing more bizarre than watching a 400lb crate catch wind and lift up and out of the trucks bed. Also, the truck stops faster than the 400lb crate sliding down the road, it rear ended me.

Robot survived.

My reputation didn't :)

Andrew Lawrence
16-02-2012, 09:50
Don't trust your non-driver friends with the controls for a moment. You think they won't shoot you in the face, they will.

compboy07
17-02-2012, 00:55
Leave the driver station on only the Classmate or not make redundant backups. Ours failed on the day we were supposed to have driver training, which led to a mess particularly because we had lost the LabView install media.

Ankit S.
17-02-2012, 01:24
Don't trust your non-driver friends with the controls for a moment. You think they won't shoot you in the face, they will.

I'm sorry, but that video was hilarious!

Don't put your #25 master links next to a tool set; when that tool set falls over and hides the master links, a frantic 30 minute search occurs. :yikes:

LemmingBot
17-02-2012, 21:19
Plugging your 5 volt camera in to a 12 volt supply. We don't know who did this... it might have been me... probably was me...

Taylor Hawkins
17-02-2012, 21:48
Never ever EVER let the mechanical engineer guys design places for electronics to go and wires to go. They will put it under a giant rotating arm and make it impossible to wire anything there.

^^ Did that this year except it was an electrical engineer that decided to put it there! He didn't quite think that one through.

Hinfoiltat
17-02-2012, 23:28
Don't force motors to turn :x