Crazy Inspection Stories

[Mike Ciance]

Who has some crazy inspection stories? I'm sure most veterans have at least a couple.

When we weighed our robot at the regional it was 129.4. After making no additions or changes it was weighed in at the Nationals at 130.8. We picked it up again and put it back down and it was 130.3, then it was 130.5. We finally got it to go down to 129.9 and passed but it is rediculous that they use such bad scales.

[Ryan Albright]

ya In 2001 at KSC they had would floor and are robot weighed 131 and then we drilled all these hole in is and got it down to 130.3. Then i got the genious idea the wood might have soemthing to do with it once we stepped off the plank of wood it went down to 128.5 so allt he holes where useless and made are robot look like crap

[Jared Russell]

At our first regionals we couldn't figure out why our team number wouldn't come up on our OI while tethered, but we could still control our robot. I and an IFI guy both double checked our team number settings by doing some binary conversion, and it seemed to match up. We replaced both the OI and RC, tried several tether cables, and were on the verge of giving up when I thought to try something.

Turns out that our team number was set to the bitwise inverse of 341 - we didn't see it because the pattern of on/off was the same, but we failed to realize that on and off were backwards! So we couldn't see any number because the inverse was four-digits long and our OI only had three.

Doh!

[ngreen]

Wow. At both regionals and championship we topped the scale at 129.8. The worst part is our inspector at championship. Made us change 3 of our 30 Amps to 20 Amps. 2 for van door motors and 1 for our light. At regional, the trained the inspectors using our robot. The only problem they found was that we hadn't flipped our dipswitches to the right team number, it was so much easier on our programmer to go from 1 to 0 to test autonomous instead of 1108 to 0.

[David66]

At nationals this year we began witha fairly young inspector who was what I like to call "by the books". Everything was going fairly well until we came upon a wire that we couldnt follow. Next thing we know there are 2 white shirted volunteers, a purple shirted FIRST guy, and one of the Innovation First guys ALL inspecting our robot. Later (Friday) we were having "radio" trouble. We were descended upon by Innovation guys on segways who determined we really had a coding problem and were stuck in autonomous. LoL, it was great.

[Dave Flowerday]

Originally posted by robohyo
The worst part is our inspector at championship. Made us change 3 of our 30 Amps to 20 Amps. 2 for van door motors and 1 for our light. At regional, the trained the inspectors using our robot.

Are you implying that the inspectors made you change those breakers when they shouldn't have? I worked as an inspector at the Championship and made several teams change out 30A breakers for 20A (I don't think I inspected you though as I didn't ask anyone to swap 30 for 20 for van door motors as the max for those is 30A). There is a good reason for this - devices like the light are allowed to be connected with smaller gauge wire. When making an electrical circuit, you want the breaker to be the weak link in the system - so that it will fail first. If you have a very large breaker in series with very small gauge wire, the wire will get hot and possibly melt before the breaker flinches. Instead you want the breaker to trip before the wire gets hot. Even the rule book states, "The circuit breaker current ratings indicated for specific circuits are the maximum allowed, and the AWG wire sizes are the minimum allowed."

As an inspector, I'd say that 1/4 to 1/3 of the teams I inspected had fairly major rules violations. Every time I pointed these out, the team would argue with me, saying "But we passed at the regionals!" It was clear to me that inspections at certain regionals were very, very lax. Please people, in the future, don't bother with the "We passed at a regional!" speech. Each event is a new competition and your robot has to pass inspection at each.

I think that the sheer number of problems we found at the Championship that should have been caught at the regionals was disturbing, and I think the FIRST staff working at the inspection area took note. I'd expect some changes next year in the inspection process.

[Gadget470]

There are many easier ways to test auto code than to flick dipswitches.. I'll post the segment of our code we used for testing some time later (upon request).

Basically, the position of the 'throttle' wheel on the drive joystick had different meanings. What meaning it was set to was shown by the LED's [programmed display]. (i.e. 4 on = auto test on button). Then we had a special "testing" button on our control box. When it was pushed, it would run a program based on the throttle position. The autonomous choice was determined by a series of dipswitches to our digital input.

[Koci]

We weighed our robot prior to inspection to make sure we would pass, and weighed 129.7. At inspection, on the exact same scale, the first time we got 130.2. We picked it up and set it down again, and got 130.0. We took it to another scale, and again got 130.0, so they let us pass.

[ngreen]

Sorry, I didn't mean it that way. The worst part was running from the inspection area to third base in the astrodome to find out we only had two twenty amp breaker (Murphy's law kicks in again) then back. They did nicely let us get by with a 20 amp fuse until we made a quick run to small parts, and then dashes to the reliant arena to barely make our practice round.

I was also amused by the fact that the regional inspector found no error like that with our robot when it was the one used to train the inspectors there.

I have been happy with the inspectors a both the regional and championship.

Flipping one dipswitch is easy. Just don't turn the robot on when it is at zero.

[Chris Nowak]

it really depends on the regional. Midwest was easy for us. The guy went down the list in a couple of minutes, and was pretty lenient. At west michigan, it took about 10-15 minutes because they went through every last thing on the list very thouroughly. We still passed both completely, but it was interesting to see how the inspections differed.

[ChrisH]

Originally posted by Koci
We weighed our robot prior to inspection to make sure we would pass, and weighed 129.7. At inspection, on the exact same scale, the first time we got 130.2. We picked it up and set it down again, and got 130.0. We took it to another scale, and again got 130.0, so they let us pass.

Based on your numbers I would say your "practice" weigh-in was on the far right scale, the first "official" weigh-in was on the middle scale and the last one was on the far left scale. The numbers would then match my observations on the relative sensitivities of the different scales used.

The inspectors all knew that we were getting different weights on different scales, but that the scales were consistent to themselves. So each one would give the same weight (within 0.1 lbs) for the same object, but what one weighed at 130.5, another would would show at 130.0 and the third about 130.3.

Since we didn't have a calibrated weight there way no way for the inspectors to tell which of the three scales was correct. I suspect it was the "lightest" one, because nobody commented on a weight difference from a previous regional on that one. Or maybe they were just too smart to say "Hey we lost some weight!" in front of an inspector.

Since we had no idea which was right, we passed anybody who could show 130.0 or less on any scale. If a machine was close, we used the light scale.

The scales used were accurate enough for the job, but the calibration was probably off due to stuff that happened in transit. It happens. Maybe somebody would like to find a set of certified weights we can use for the Championship next year? I don't think FIRST wants to have to haul them around everywhere.

Remember, your target weight should be something less than 130 anyway. Leave yourself at least a pound of margin to take the differences in scales into account. You can always add a little weight if the scale will let you get away with it, it's a lot harder to take it off.

[ChrisH]

Originally posted by Chris Nowak
it really depends on the regional. Midwest was easy for us. The guy went down the list in a couple of minutes, and was pretty lenient. At west michigan, it took about 10-15 minutes because they went through every last thing on the list very thouroughly. We still passed both completely, but it was interesting to see how the inspections differed.

The fastest complete inspection I did at Houston took 20 minutes. That was for a bare bones robot with no pnuematics and only two drive motors. Times went up from there depending on the robot's complexity and the messiness of the wiring or plumbing. Average was around 30 minutes, and in one case it took an hour because I thought there was something wrong and couldn't figure out what. I eventually caught the compressor in series with the pressure switch and the regulators in reverse order, but the wiring was so tangled it was hard to see.

So a helpful hint for next year. Make life easy on yourself and your inspectors, lay out your wiring and plumbling neatly and in a fashion that is easy to trace. Labels help alot too. The easier to trace things are, the less we think there is something to hide.

[Matt Reiland]

Originally posted by Dave Flowerday

As an inspector, I'd say that 1/4 to 1/3 of the teams I inspected had fairly major rules violations. Every time I pointed these out, the team would argue with me, saying "But we passed at the regionals!" It was clear to me that inspections at certain regionals were very, very lax. Please people, in the future, don't bother with the "We passed at a regional!" speech. Each event is a new competition and your robot has to pass inspection at each.

I think that the sheer number of problems we found at the Championship that should have been caught at the regionals was disturbing, and I think the FIRST staff working at the inspection area took note. I'd expect some changes next year in the inspection process.

AMEN Dave,

I tried my hand out at inspecting at West Michigan and was amazed at how many people were actually angry at me for following an inspection sheet that was handed out to everyone before the robots shipped. I saw everything from Victor 883's to Custom Valves to wrong breakers, some were really big violations that I felt may have given the team an advantage. Others I let go by even though we followed them on our robot - modification of the air cylinders, FRC Techs clarified that removing the pin from the cylinder body was a modification and not allowed, however nearly everyone removed it anyway. The same story from nearly everyone, "But why are you hassling me we have already competed in two regionals" or "The breakers were tripping so we used bigger ones", or "Even though it isn't allowed on the check off sheet it still works the way it is". How about teams that didn't want to change the wiring because they said they didn't have a computer or the current program to change it and make it work with the new wiring? Are you kidding me? I treated everyone the same (Even the teams that built in our same area at the tech center got busted with the wrong valves), my team was not there competing at the event. It shouldn't be that hard to enforce a checkoff sheet that was handed out before shipment of the robot should it?

[Chris Nowak]

Originally posted by ChrisH
The fastest complete inspection I did at Houston took 20 minutes. That was for a bare bones robot with no pnuematics and only two drive motors. Times went up from there depending on the robot's complexity and the messiness of the wiring or plumbing. Average was around 30 minutes, and in one case it took an hour because I thought there was something wrong and couldn't figure out what. I eventually caught the compressor in series with the pressure switch and the regulators in reverse order, but the wiring was so tangled it was hard to see.

So a helpful hint for next year. Make life easy on yourself and your inspectors, lay out your wiring and plumbling neatly and in a fashion that is easy to trace. Labels help alot too. The easier to trace things are, the less we think there is something to hide.

yeah, we had a very very neat robot and I think the inspectors liked us. Cant say anything about nats inspection though because I was off with the scouting team, and our backup driver handles inspection most of the time anyway. cuz I am on the animation team. Also, I dont know about those times, I was probably exaggerating, but the only problem we had AT ALL was that one of the inspectors suggested that we round the corners down a bit. That was at West Michigan. But again, I have no idea how nats inspection went.

[David Lantz]

We were very lucky at Houston. Our inspection took a maximum of 10 minutes. This was all thanks to the great efforts of one of my teammates who did an exelent job on the wiring. The inspector was very very picky on everything but couldn't find one thing wrong with our bot. I was very proud when he finally gave up and said that there was nothing wrong with our robot.

Oh wait... he did want us to file one corner of the chaise that had been dented during the practice rounds and had one small burr sticking out...