Al's 2016 Inspection Thread

[ChuckDickerson]

Originally Posted by jspatz1

AM now sells other white air tanks, but does not mention whether they are Clippard. Is it ONLY the P/N AVT-PP-41 tank (which I believe is labeled as such) that is illegal?

Yes. Only the white tanks with green Clippard writing are illegal. Any white tank sold by AndyMark now is legal as are the black Clippards.

[Al Skierkiewicz]

Sorry I have been away from CD this week as I attended the Duluth Regionals. So I have a few things to remind teams of following that event.

1. What is a robot side? Well it is the frame that exists between two exterior corners as determined by the "string test". If you wrap a string or tape measure around the FRAME PERIMETER, a side is between two corners. If your robot is rectangular then it has four sides. If your robot is "U" shaped to pick up balls, then the side that has the opening is one side, not two. If the distance from one outside corner to the next is less than 8", then the entire side must be covered in bumper. In no case can a bumper segment (as determined by the backing) be less than 8" long.
2. If your made bumper segments that are less than 8" long, you will have to change them to comply. Teams that have smaller FRAME PERMIMETERs can achieve this with a change in the frame aspect ratio to allow a wider frame segment on each side of the opening of the ball pickup.
3. Teams that are using tank track kits will have a challenge meeting the bumper rules. The front and back of the track needs to be covered by bumpers but they do not have to be at the same height. All bumpers must be in the BUMPER ZONE, the 4-12 inches above the floor.
4. Bumpers need to be backed up by frame as the rules specify. This is a challenging one for teams, but this game is very rough on robots and improving your frame and bumper attachments will go far in keeping you playing throughout the season.
5. Hard parts on the bumpers can only extend outside the FRAME PERIMETER by 1 inch. If you are using drywall screws to attach your bumpers, most will exceed the 1" rule. The end of the screw will damage your bumpers and other robots, and may injure your team members. You will be asked to show your bumper attachment during inspection. #12, 3/4" screws work great if you don't have a better attachment worked out. They are available everywhere.
6. MDF, HDF, chipboard and paper board are not "solid, robust wood". 3/4" plywood is best, but hardwoods in the 3/4" dimension work as well but are more expensive. 5 inch +/- 1/2" is the height rule for the backing board.
7. Teams are having many issues related to electrical. If you haven't seen the game played, I can tell you going over any defense is hard on robots. Please check all electrical connections but in particular make sure the battery, PDP and main breaker connections are tight. If you crimp your own #6 terminals, then use a crimper meant for that service. Some terminals can also be crimped in the corner of a vise in a pinch. When done correctly, the wire will not move around in the terminal and you will not be able to pull the wire out of the terminal. The severe shock robots receive this year cause brownout conditions on loose electrical connections.
8. Check other wiring, particularly power wiring to RoboRio, PCM and VRM modules and all CAN buss wiring. Give every wire a "tug test" to insure the wire doesn't pull out. I found more than 20 robots this weekend that had one or more loose connections. Most often teams have simply not stripped the wire long enough for the push terminals to grab the wire.
When in doubt on anything, come over and ask the LRI or other inspectors for advice or assistance. Small problems become huge on Friday afternoon or Saturday morning.

[billbo911]

Thanks again Al for this annual thread!

Who would have imagined that Bumpers would have such a big part in this thread? One year without them and many forget how important they are.

Electrical robustness is indeed huge this year. If you have a questionable connection somewhere in your machine, this game will expose it, and likely at the worst time possible!

[Jacob C.]

Originally Posted by Al Skierkiewicz

[SNIP]
8. Check other wiring, particularly power wiring to RoboRio, PCM and VRM modules and all CAN buss wiring. Give every wire a "tug test" to insure the wire doesn't pull out. I found more than 20 robots this weekend that had one or more loose connections. Most often teams have simply not stripped the wire long enough for the push terminals to grab the wire.
When in doubt on anything, come over and ask the LRI or other inspectors for advice or assistance. Small problems become huge on Friday afternoon or Saturday morning.

I can't emphasize this enough.

I was the FTAA for the Kettering University District this past weekend and there were a lot of instances of teams losing connection with the field because of radio and roboRIO power issues.

Specifically I would add the following:

1. Make sure the power connection plugged into your radio is secure. There were many cases where teams encountered mild to large impacts and had their radio either reboot (which takes a good 60 seconds to reconnect to the field) or lose power entirely. My personal choice for this is hot glue as you can still peel it off by hand if you need to, but just make sure it's secure.

2. Standard consumer-grade Velcro is not sufficient to secure small electrical components. There were several robots that lost radio/roboRIO power because components came loose during a match. There was even one match where a team's radio ended up disconnected and on the field. Please make sure you're using robust attachment methods - zip ties can work ok in a pinch, but hardware is usually the best method.

[dradel]

Al,
Question for you regarding the "dump" valve on pneumatic system.
Does it matter if the valve is before or after the regulator? Ie on high pressure side or low pressure side, as long as it completely vents all pressure from system.
I couldn't seem to find a rule that dictates placement. Closest I could find was R83 stating the only devices that "may" be on high side.

[Al Skierkiewicz]

R89 Any pressure vent plug must be:
A. connected to the pneumatic circuit such that, when manually operated, it will vent to the
atmosphere to relieve all stored pressure in a reasonable amount of time, and
B. placed on the ROBOT so that it is visible and easily accessible.

When you place it downstream from the regulator is takes longer to release all pressure so that is why most people put it upstream.

[dradel]

My team couldn't pass inspection due to being on low side. When the students questioned this the inspector just walked away and wouldn't listen to reading of rules or reason.
Personally I don't think it matters one way or the other, but in the name of safety it is safer on the low side in my opinion.

[rsisk]

Two things would have helped the majority of teams at San Diego this year...


1. Read AND UNDERSTAND the bumper rules
2. Update your driverstation software

This is the advice I sent to all the SD teams as their LRI...

DRIVER STATION UPDATE
Team update 12 included an update to the Driver station software. Your driver station MUST be updated before you can compete in San Diego. Please update your software before you come to the competition.

https://decibel.ni.com/content/docs/DOC-46527

COST ACCOUNTING WORKSHEET
Every team must show a completed Cost Accounting Worksheet (we used to call them your Bill of Materials) in order to pass inspection. You can find a suggested format attached. Please have this filled out before you come to the competition

INSPECTION WORKSHEET
Want to get through inspection quickly? Have a look at the attached inspection checklist for the rules you must comply with before you will be allowed to compete.

BUMPERS
Make sure your bumpers are compliant with Section 4.7 Bumper Rules in the Game Manual. If you think there might be a problem, be sure to bring the appropriate material and parts to correct your bumpers at the competition. You must have legal bumpers (both red and blue) before you can compete.

[FrankJ]

Originally Posted by dradel

My team couldn't pass inspection due to being on low side. When the students questioned this the inspector just walked away and wouldn't listen to reading of rules or reason.
Personally I don't think it matters one way or the other, but in the name of safety it is safer on the low side in my opinion.

R89 requires the vent valve release all pressure in the system. If the regulator is set to 0 pressure, a low (working) pressure vent will not vent the high pressure (stored) side.

[Mike Schreiber]

I noticed a discrepancy in interpretation between myself and another inspector at my event last weekend with regard to what counts as 'automotive motors' and since I will be inspecting at several more events this year I'd like a bit of clarification.

To qualify as an automotive motor, does it have to be a production part on a vehicle. In the interest of cost savings, is there any reason an aftermarket part that is intended for the same function would not be acceptable?

Are power lift gate motors considered door motors? What if these vehicles are referred to as 5 door models (hatchbacks).

If we cannot remove a COTS gearbox from the window motor, can we do so on other automotive motors? What if you could buy that motor without the gearbox? What is considered integral to the mechanical integrity of the motor?

Perhaps this would be better on Q&A, but since it doesn't really impact my team I wasn't going to request we ask it there.

[dradel]

Originally Posted by FrankJ

R89 requires the vent valve release all pressure in the system. If the regulator is set to 0 pressure, a low (working) pressure vent will not vent the high pressure (stored) side.

Ok I'll bite, why would the regulator be set to zero?
My point is the rule is open to not only interpretation, but also becomes a matter of opinion. The rules don't say must or shall be on the high side, but rather says must have one.
We had one that infact did empty the system completely, he just didn't like it on the low side, and seeing as there is no rule that says must be on high side it became his opinion.

How are teams going to be able to figure out what one persons opinion is going to be?

[Jon Stratis]

Originally Posted by dradel

Ok I'll bite, why would the regulator be set to zero?
My point is the rule is open to not only interpretation, but also becomes a matter of opinion. The rules don't say must or shall be on the high side, but rather says must have one.
We had one that infact did empty the system completely, he just didn't like it on the low side, and seeing as there is no rule that says must be on high side it became his opinion.

How are teams going to be able to figure out what one persons opinion is going to be?

That's why teams ALWAYS have the right to appeal to the LRI. I know as an LRI, I will walk a team through any rule in question and make sure they understand why the ruling is the way it is. Most, if not all, of the other LRI's I know will do the same.

It's unfortunate, but it's practically an impossibility to properly train every inspector for every situation they may encounter when looking at a robot. I always tell my inspectors that if they aren't 100% positive about something, they need to come get me. If a team has a problem with a ruling, the inspector need to come get me. It makes it a busy day for me (50k steps during the 3 days at the Duluth regional alone!), but that's why I'm there!

[Alan Anderson]

Originally Posted by Al Skierkiewicz

When you place it downstream from the regulator is takes longer to release all pressure so that is why most people put it upstream.

That's usually the case, but not always. If you have working-pressure accumulators, for whatever reason, it can easily take less time to release if your dump valve is on the low side of the primary regulator.

[dradel]

Part of the issue is that the students don't want to come off as rude by pushing back against the inspector.
Don't want the proverbial target on their backs for the rest of event.
I was unable to be at the event this weekend, and would have pushed back and asked for LRI to come to pit had I been there.
They were able to replumb the system with the help of another team, but that time spent was really wanted to be spent on the practice field or in practice matches.

[Jon Stratis]

I can understand not wanting to be rude, and it can be difficult to come off gracious while tSelling an inspector he's wrong. I suggest a simple wording of "we've interpreted that rule differently, would you mind getting the LRI for a second opinion?" Train your students on that, and you should be golden