Al's Annual Inspection Thread 2013

[Al Skierkiewicz]

Everyone,
I am starting this a little early this year to remind everyone of a few things during this final week of build.
1. The Inspection Checklist was released last week. Please use it to check over your robot prior to bagging next Tuesday.
2. There are significantly more motor choices this year, however, that list is not unlimited. There are specific quantities of each motor that can be used on your robot. The motor list is separate from the Inspection Checklist since it so long.
3. This year bumpers do not need to be bagged so don't worry how you are going to fit them in the bag. You can, of course, add them to your robot and include them in the bag. They will not count against your 30 lb allowance if you choose to keep them separate.
4. Don't forget you need to include belay points on your robot. There are no exceptions.

Enjoy your last week of build. I will add to this list after stop build. I hope the teams in the northeast have dug out of the heavy snow and everyone is safe and secure. Good luck all.

[Richard Wallace]

Thanks for doing this thread every year, Al. Inspection is an important part of the events, but it does not need to take a lot of time if teams prepare well. Less time with your robot inspector means more time for other kinds of fun, like practice for your drive team.

Thanks also for the special mention of motors. :D My favorite topic!

The list of legal motors for 2013 (see <R32>) is very long, but there are some old friends missing -- for example, the FP motors from previous seasons are not legal any more. It will speed up inspection if teams can either (1) install motors so their markings are visible to be checked against the legal motor list, or (2) when that is not feasible, mark the motor's part number nearby or have a list handy to show the inspector which motors are used.

[rsisk]

Here is the link to the Inspection Checklist, it's also linked on the Competition Manual page on the FIRST web site

http://www.usfirst.org/sites/default/files/uploadedFiles/Robotics_Programs/FRC/Game_and_Season__Info/2013/2013FRCInspectionChecklist.pdf

[Wayne Doenges]

There a few things you can do before you get to Bag and Tag and have to deal with the inspectors :D

1) Remember ONE wire per Wago.
2) Sharp edges. Remove them. I don't like to see blood, especially my own :ahh:
3) Make sure your 120 Amp breaker (that switch that turns your robot on/off) should be easily accessible. I ask the teams what would happen if your robot started smoking and nobody could reach the switch to turn your robot off? Weiney roast.
4) Review the wire color coding and size.
5) If you are using a camera, make sure it is isolated from the frame. To check, get a multimeter/ohmmeter and check for continuity from the frame to the PD battery post. It should read over 10k Ohms.

[Jon Stratis]

All teams should be familiar with Bag and Tag now, but there are still teams every year that don't have their form easily available when they get to the venue - get a plastic sheet protector and tape it to your bag, then put the form in there!

My list of items every team should check now, while they still have time to fix them:

- Check that the FRAME PERIMETER is <= 112”
This does NOT include minor protrusions like bolt heads.

- Check the starting configuration
Everything on the robot must be within the vertical projection of the FRAME PERIMETER
This can be checked by pushing the robot against the wall

- Check that the weight of the robot is <= 120 lbs, and the weight of the bumpers is <= 20 lbs.

- Check that all motors are on the legal motor list
Make sure there are no Fisher Price motors, and compare all motors to Table 4-1.

- Perform a basic check of the electrical system
Use a multimeter to ensure the chassis is electrically isolated.
Check for appropriate wire gauge sizes

- Perform a basic check on any pneumatic systems
Ensure proper stored and working pressure
Check the system against the minimum system shown in R79

- Ensure the robot has appropriate belaying points (required for every team)
These can be eyelets with a ¾” opening or exposed structural members
If you doubt the robot can be supported by these points, have the team lift it
Be extremely strict about sharp edges near the belaying point
Suggest wrapping edges of the belaying point in duct tape, if frame is used

- Check that the battery is secure
Think about what would happen to the battery if the robot was upside down

[tsaksa]

Any advice for a first time robot inspector? I would be particularly interested in any threads or documentation that has more examples on what is and is not legal for bumpers this year. i am not sure I know what is really acceptable for a corner climbing robot.

[dtengineering]

Wow! Absolutely nothing in there about safety shields for high speed rotating equipment.

Given the number of shooters that will be running wheels at several times their design speed, I really expected something about "high speed rotating mechanisms are shielded to reduce the likelihood of injury during testing or in the case of failure of a rotating component".

I mean R08 covers the general concept:

ROBOT parts shall not be made from hazardous materials, be unsafe, cause an unsafe condition, or interfere with the operation of other ROBOTS.


But I was hoping for something more specific, so that all teams would know, in advance, that exposed shooter wheels likely "cause an unsafe condition".

Jason

[dtengineering]

My list of items every team should check now, while they still have time to fix them:...



And my favorite... check for sharp edges and burrs and file them down or tape them up so they don't cut anyone.

A colleague of mine would tell me he'd always have the kids wash and polish their drag car (inside and out, including the engine) before going to a race. It always helped with tech inspection because first of all it meant that the kids had been over the car and had looked at all the little things, but it also meant that when the inspectors walked up to the car they had a positive impression that care, attention and professionalism had gone into the details.

Teams that take care of the little things often have much less trouble with the big things!

Jason

[Al Skierkiewicz]

t,
Anyone of us can ask specific questions but to list everything we have seen over the years would close CD down. Teams are very creative...

[DELurker]

After taking a brief look over the form, I'd like to point out that Kickoff was January 5th, 2013.

[DonRotolo]

After taking a brief look over the form, I'd like to point out that Kickoff was January 5th, 2013.
Oh yeah? Prove it! :p

[Jaxom]

3) Make sure your 120 Amp breaker (that switch that turns your robot on/off) should be easily accessible. I ask the teams what would happen if your robot started smoking and nobody could reach the switch to turn your robot off? Weiney roast.

Please ask yourself..."If my robot is on fire and the pneumatics are randomly activating, is my main breaker someplace that I want to put MY hand?" (same question for your manual air release). If your answer is "no" then probably everyone else thinks the same.

[theawesome1730]

Make sure your battery has a secure mount, wouldn't want it to fall off while (whilst?) 30pt climbing. Keep your electrical systems organized and labeled efficiently. The less time it takes inspectors to go through your robot, the better their impression of your team (and the less things they find wrong :D .) And don't forget to be kind and friendly, there is a lot of stress during inspection and it makes things simpler for both sides.

[Wayne Doenges]

Wow! Absolutely nothing in there about safety shields for high speed rotating equipment.

Given the number of shooters that will be running wheels at several times their design speed, I really expected something about "high speed rotating mechanisms are shielded to reduce the likelihood of injury during testing or in the case of failure of a rotating component".


What do you mean absolutely nothing about safety shields? ^ there it is :D

Remember that the Robot Inspectors are your friends and are there to help you. If we find something wrong, with your robot, don't take in personnal.

[Al Skierkiewicz]

Well,
Now that everyone has bagged their robot using the official FRC bag and secure seal tag, you are good to go right? Not quite yet.
One of the biggest issues for inspectors every year with B&T is having teams produce the B&T forms. You should have filled this item out when you bagged the robot on Tuesday. Now is the time to make copies and insure that the original goes to someone who will be moving with the robot to competition. On a number of occasions, we have had teams with the form in the hands of a teacher who didn't travel with the team or the team captain who got the flu just before the competition. If you want to maximize your time on practice day, be sure to have the form handy when you arrive.

This year, the new rules will confuse some people. At this time, all robots must have two belay points on their chassis. It doesn't matter if you can't climb or intend to climb or even wish to climb, you must have them on the robot to pass inspection.

While there are a lot of motors on the allowed list this year, some past motors are no longer legal. Now is the time to check if your motors are on the allowed list and be prepared to change them at competition if they are not. Notably, the Globe motor and Fisher Price motors are no longer legal. The motors must be identifiable so no painting or other than allowed modifications are legal.

Bumpers...Every year this is a problem. We have gone to great lengths to simplify this. Bumpers must cover 8" of frame on either side of any exterior corner. Bumpers can be built after stop build, they do not count towards the 30lb allowance of parts to be carried in at competition.

First has tried to think of everything you might come up with in design and planned for that. However, you are really good and sometimes there are things that we didn't think of. The Q&A is your friend. If you thought of something, I bet someone else did too and already asked the question. If it was of some great importance, FRC also added it to a Team Update. Now is the time to check through both of these resources. Inspectors will have up to date lists of items that affect your robot construction. Each week they will be inspecting for these items. If needed, a revised inspection checklist (also available on the First website) will be issued.

That is all for this installment. Good Luck everyone.

[Jon Stratis]

Well,
Now that everyone has bagged their robot using the official FRC bag and secure seal tag, you are good to go right? Not quite yet.
One of the biggest issues for inspectors every year with B&T is having teams produce the B&T forms. You should have filled this item out when you bagged the robot on Tuesday. Now is the time to make copies and insure that the original goes to someone who will be moving with the robot to competition. On a number of occasions, we have had teams with the form in the hands of a teacher who didn't travel with the team or the team captain who got the flu just before the competition. If you want to maximize your time on practice day, be sure to have the form handy when you arrive.

The best way I've seen to avoid forgetting your form is to securely attach it to your bag! Get some duct tape and tape a sheet protector to the bag. Slide the form into the sheet protector and you'll never forget it.

Please note, that if you're transporting your robot to competition in the back of a truck or on an uncovered trailer, you'll want to keep wind in mind... You don't want the form blowing away while cruising down the highway 100 miles from competition!

[lcoreyl]

Wow! Absolutely nothing in there about safety shields for high speed rotating equipment.

Given the number of shooters that will be running wheels at several times their design speed, I really expected something about "high speed rotating mechanisms are shielded to reduce the likelihood of injury during testing or in the case of failure of a rotating component".


ditto to that! I'm also noticing a lot of this in videos (some labeled as reveal) with no wheel covers.

I'm having flashbacks to breakaway when we spent precious manhours making sure we didn't allow balls under our bot only to have FIRST decide that as long as a whole lot of people are doing it, then lets not follow the rules...

[Wayne Doenges]

Please note, that if you're transporting your robot to competition in the back of a truck or on an uncovered trailer, you'll want to keep wind in mind... You don't want the form blowing away while cruising down the highway 100 miles from competition!
If you are transporting your robot this way, please cover it up.
Last year, at SMR, a team brought their bot in a truck bed. They also used aluminum duct work for the basketballs. The ducts shredded their bag and it took awhile for them to get inspected.
Also, I hope you didn't put your B&T sheet inside the bag with the robot :ahh:

[nicholsjj]

After pre-inspecting a team I would also encourage every team to look at their robots in the bag and see that they have the right wireless bridge. Veteran teams really need to make sure that they use the bridge that they got in the kop to pass. The old rev. A bridge will not pass inspection this year. I would also like to remind teams to update their drive stations.

The best way to get through inspections quickly is to go into the thursday of regionals with a plan. Make a list of every thing that your team will have to do to get through inspections. Be safe and do not get in a hurry when you do start making these changes and you will have a successful thursday.::safety::

[Phalanx]

Wow! Absolutely nothing in there about safety shields for high speed rotating equipment.
Jason

Add me to the list for this one too. I think this could be a major safety issue. I've seen a few with wheels/discs spinning UN-captured or UN-encapsulated at very high RPM's that are probably beyond tolerances of the wheels/discs.

[Al Skierkiewicz]

OK,
I will bring this up but consider that rotating devices do come under the Safety Rule
R08
ROBOT parts shall not be made from hazardous materials, be unsafe, cause an unsafe condition, or interfere with the
operation of other ROBOTS.

A greater concern is materials used for friction on the rotating device. Please be sure that you have chosen wisely when you assembled your spinner/wheel/tire. Some of the wheels used in the past are not meant for the high RPM you may be running on your shooter.

[dchartley]

We built a curved 1/8" thick aluminum guard for our high speed pneumatic wheel so we wouldn't have problems during inspection because this had been mentioned in another thread.

Doug

[Wayne Doenges]

We are using the AM plaction wheels but we rivet and glue the tread on.
No failures yet.

Rememer, when you get to your regional, do not unbag your bot until told to do so.

[Iaquinto.Joe]

Rememer, when you get to your regional, do not unbag your bot until told to do so.

Oh yes, we had someone open it at our second regional too early. It was a sticky situation explaining that.

[Hebrew]

Is there any rule that can actually make our robot illegal if our shooter is not shielded? We are going to Lake Superior next week and the attached image is what it looks like (Our robot is slightly upgraded since then but the shooter is pretty much the same)

Adding a shield to our robot would be difficult since it is extremely close to the weight limit and we cannot mount it very securely. We have tested our shooter rigorously in the 2 weeks leading to the stop build day and never had an issue with it or the bolts loosening once setup properly.

If inspectors would require us to not use our shooter or shield it, it would be devastating.

[Alan Anderson]

Is there any rule that can actually make our robot illegal if our shooter is not shielded?

<R08> applies.

The TechnoKats ran unshielded high-RPM wheels on the disc shooter for weeks with no failures. The practice 'bot still lacks a shield at the moment. But the robot in the bag right now has a guard in place to keep it safe in case something comes apart at speed.

[Hebrew]

<R08> applies.

The TechnoKats ran unshielded high-RPM wheels on the disc shooter for weeks with no failures. The practice 'bot still lacks a shield at the moment. But the robot in the bag right now has a guard in place to keep it safe in case something comes apart at speed.
If the shooter is securely mounted, and lock tight is used would that really cause a more unsafe condition than the Frisbee which is being shot? It will be interesting to see if an open shooter will pass inspection....but if not:

Would a simple shield over the wheels suffice, or would it have to be over the entire top if inspectors claim it to be unsafe? We will probably have to prepare a piece of metal to be mounted just in-case inspectors deem our robot unsafe.

[Brandon_L]

Hey Al-

Would you be willing to comment on the safety aspect of our shooter? (Image: http://www.chiefdelphi.com/media/photos/38634)

Pretty much questioning if you were inspecting this robot, would you pass it?

Specifics:
8" Andymark pneumatics balanced by stacked washers on two bolts per wheel, with locknuts. The wheels are directly mounted to the CIM shafts by retaining rings (two stacked on one another to ensure it doesn't come out). The CIM mounts are VERY sturdy 1/4" thick aluminum and everything is securely bolted in/nylock nut secured.

Thank you very mucho for input

[Al Skierkiewicz]

Brandon et al,
I look at exposed wheels and get scared. The reason is many years ago when open reel tape recorders were still in use, one of my co-workers was fast winding 2" audio tape and just before the end of the reel he started slowing the reels in prep for removing the tape from the machine. He lost his attention for just a second and his fingers got caught in the open reel. He was lucky, some deep cuts but nothing broken or torn off. His bandage/splint stayed with him for almost 6 months. I still think of that day when I look at shooters.
What you have to think to yourself is "what safety issue does this cause when I run up the motors in the pit or practice field?" If you are scared, perhaps you need to do something. The GDC is thinking about this I am sure. In the past we were directed that high speed rotating devices need some form of cover. If asked for my opinion today, I would recommend a cover.

[Jaxom]

The 4 biggest issues I saw as an inspector at Hub City were:
1) Unshielded shooter wheels. I don't have an exact count but I'd be surprised to find out that fewer than 75% of teams had to add shields.
2) R86 violations. I personally saw at least 10 pneumatic systems; 9 of them had plastic tubing between the compressor & pressure relief valve & had to do rework to become legal. The good news was that I only had to help one team calibrate theirs.
3) Frame perimeter excursions. Way too many robots had to move things so they weren't sticking out past the frame in starting position.
4) Unshielded shooter wheels. I'd be amazed if more than 25% of the teams actually came in with proper shielding.

We also had the "normal" kinds of issues -- like sharp edges and battery terminals that weren't properly insulated -- that are easy fixes and should have never been seen by inspectors. We also had lots of poorly constructed bumpers. I spent most of Friday on the field; along with the things I was finding in queuing the head ref kept asking me to talk with teams about their bumpers falling off or sagging.

[Jay O'Donnell]

1) Unshielded shooter wheels. I don't have an exact count but I'd be surprised to find out that fewer than 75% of teams had to add shields.

4) Unshielded shooter wheels. I'd be amazed if more than 25% of the teams actually came in with proper shielding.

Sorry if I'm missing something but aren't these two the same thing?

[Jaxom]

Sorry if I'm missing something but aren't these two the same thing?

Yep. I put this in twice for emphasis; I'm pretty sure that adding shielding took well over 50% of the total time teams put in fixing inspection issues.

We had a number of discussions with teams (fortunately, almost all were actual discussions instead of arguments) about the necessity for this. R08 (and a LRI that stuck to his guns) won every time.

If you knew me, you'd have been looking for a smart-aleck comment. :rolleyes:

[Dr.Bot]

Do robots who never intend to climb the pyramid require belay points. The rules seem to be pretty adamant that all robots need them, but I am note sure why this would be a requirement for a robot that never is going to climb?

[jvriezen]

Do robots who never intend to climb the pyramid require belay points. The rules seem to be pretty adamant that all robots need them, but I am note sure why this would be a requirement for a robot that never is going to climb?

Yes, all bots need them. From the Q&A:

Q194
Q.R10 If you don't plan on climbing above zone 1, do you still need to provide fasteners/mounting points
for the belay system on your robot? If you don't will this violate R10?
A.Yes, [R10] requires all ROBOTS to have attachment points for the belay system.

[JohnSchneider]

The 4 biggest issues I saw as an inspector at Hub City were:
1) Unshielded shooter wheels. I don't have an exact count but I'd be surprised to find out that fewer than 75% of teams had to add shields.
2) R86 violations. I personally saw at least 10 pneumatic systems; 9 of them had plastic tubing between the compressor & pressure relief valve & had to do rework to become legal. The good news was that I only had to help one team calibrate theirs.
3) Frame perimeter excursions. Way too many robots had to move things so they weren't sticking out past the frame in starting position.
4) Unshielded shooter wheels. I'd be amazed if more than 25% of the teams actually came in with proper shielding.

We also had the "normal" kinds of issues -- like sharp edges and battery terminals that weren't properly insulated -- that are easy fixes and should have never been seen by inspectors. We also had lots of poorly constructed bumpers. I spent most of Friday on the field; along with the things I was finding in queuing the head ref kept asking me to talk with teams about their bumpers falling off or sagging.


The 2 teams we started allied with Friday hadn't been inspected and didn't have bumpers yet. I had to keep going back and forth making sure they'd finish on time and that they had paint/Velcro/whatever. I can understand non compliant bumpers....but when your robot is just a drivetrain how do you not have bumpers at all @-@

[Wayne Doenges]

I will be inspecting at BMR and CRR this year
I will definetly call the teams on guarding of any high speed spinning devices ::safety::
As for the belaying points on ALL robot, the GDC probably felt it was better to say all bots had to have them then have someone lawyering the rule.

[Al Skierkiewicz]

Sorry I have been away from this column for a while but after some reports this weekend I have to add something on bumpers.
Everyone, we really tried to improve the bumper rules and make them easy and understandable. There are some nice drawings that are part of the rule, in particular Figure 4-4. However, please note, the pool noodles and the bumper rules do not allow for the addition of weight to increase the overall weight of the robot. You may not add steel rod, brass, shot or other high mass material to the interior of the pool noodles. Also note that the optional angle stock shown in Figure 4-4 is specified as aluminum. If your bumpers are modified in a such a way, please be prepared to remove the additional weight at your event.

As a reminder, any time you make modifications to your robot during competition, it is required to be reinspected. This includes changes you might make while in the queue waiting for a match. To compete without inspection puts you and your alliance at risk. Inspectors are happy to check your robot anytime during the weekend. I recommend that everyone checks with the LRI prior to making modifications to be sure you are planning something legal and within weight for your robot.

[dtengineering]

...I have to add something on bumpers.
Everyone, we really tried to improve the bumper rules and make them easy and understandable. ... You may not add steel rod, brass, shot or other high mass material to the interior of the pool noodles. ... This includes changes you might make while in the queue waiting for a match.

I might be reading "between the lines" a bit here, Al... but I think your post is perhaps more restrained, positive and polite than something I might have been tempted to post.

Kudos to the inspector who found the steel rod inside the pool noodles for not immediately using said foam-covered rods to deliver a brief and brutal lesson on bumpers! :yikes:

I mean, I'm having a hard time believing that a team really didn't know what was going on here. I remember being a clueless rookie, but this year's bumper rules are pretty hard to miss... or misunderstand.

Jason

[Wayne Doenges]

At BMR, we had to tell quite few teams that they needed to put a guard over their shooting wheels.

[HumblePie]

Al,

We had an issue at a week 3 regional with our non-relieving regulator being deemed illegal by the LRI. Obviously, it was news to us as we had passed inspection at our week 1 regional. Also, I saw several other robots with the "illegal" type (evidenced by the yellow locking ring). Fortunately, we had a relieving style on our practice robot and we were able to change it out. I've found nothing in the rules that precludes a non-relieving regulator. Care to comment?

[Nemo]

As a reminder, any time you make modifications to your robot during competition, it is required to be reinspected. This includes changes you might make while in the queue waiting for a match. To compete without inspection puts you and your alliance at risk. Inspectors are happy to check your robot anytime during the weekend. I recommend that everyone checks with the LRI prior to making modifications to be sure you are planning something legal and within weight for your robot.

Our team went through inspection something like eight times in Kansas City, because we kept changing things between matches. The inspectors were very nice about it. It wasn't any hassle at all - we just kept them in the loop and it didn't take much extra time.

[Al Skierkiewicz]

R78
The only pneumatic system items permitted on 2013 FRC ROBOTS include the items listed below.
G. Pressure regulators with a maximum bypass pressure of no more than 60 psi,

R81
“Stored” air pressure on the ROBOT must be no greater than 120 psi. “Working” air pressure on the ROBOT must be
no greater than 60 psi. All working air must be provided through one primary adjustable pressure regulator.
Norgren regulator P/N: R07-100-RNEA recommended.

Jason,
I included the weight reference as many of the events this year have had a robot show up with weight added in some form.

[Tristan Lall]

We had an issue at a week 3 regional with our non-relieving regulator being deemed illegal by the LRI. Obviously, it was news to us as we had passed inspection at our week 1 regional. Also, I saw several other robots with the "illegal" type (evidenced by the yellow locking ring). Fortunately, we had a relieving style on our practice robot and we were able to change it out. I've found nothing in the rules that precludes a non-relieving regulator. Care to comment?
The Norgren R07-100-RNEA (http://resources.norgren.com/document_resources/pdf/USNEX%20R07,%20R46%20Regs.pdf) (all-black) and Monnier 101-3002-1 (http://www.monnier.com/92831-catalogbackup.pdf) (black and metallic with yellow ring) regulators that have been supplied in many past KOPs are relieving regulators. (But note that Monnier sells very similar models that are not relieving.) While there was once a rule that specified the order of these regulators (to no useful effect), it has thankfully been eliminated.

And as you noted, the rules don't specify a relieving regulator this year. They do call for a regulator with "a maximum bypass pressure of no more than 60 psi". While I'm not familiar with that terminology in the context of a pneumatic system, by analogy to hydraulics,1 if the atmosphere is the ambient-pressure reservoir, then a relieving regulator would be equivalent to a bypass regulator. (Note also that this would require this to be the maximum output pressure rating, not the maximum pressure that could be bypassed—which would be a nonsensical feature.)

If the basis of the objection was that it was a yellow-ringed Monnier 101-3002-1 used as the primary regulator, the inspector would have been right in any of the past dozen or so years, but in a cruel twist of fate, would have been wrong this year.

If it was because it was a non-relieving regulator, consider asking the Q&A to clarify whether the 60 lb/in2 "bypass" language implies a requirement for relieving regulators only. While that sounds sensible, this is a double-edged sword: while the R07-100-RNEA would be legal, other identical-looking R07-series Norgren regulators (http://cdn.norgren.com/pdf/R07.pdf) can be adjusted up to 7 bar or 100 lb/in2.

Definitely feel free to provide us with the model (and/or KOP source) of the part you're using, to clarify whether it meets all applicable rules.

1 In hydraulics, a bypass loop is used on regulators located after a pump, so as to limit the pressure on the input side of the regulator and avoid overtaxing the pump. Instead of overpressurizing the input, it bypasses the regulator and returns that excess fluid to the reservoir.

[Siri]

At BMR, we had to tell quite few teams that they needed to put a guard over their shooting wheels.Huh, we still haven't been asked to do this. We have one ready, but what sort of guards have the teams needed (i.e. thickness)?

[Rosiebotboss]

I will try to poke a 3/4 inch dowel (or something similar to the diameter of a finger) into the wheel(s). If I can contact any portion of the wheel other than the actual diameter that comes in contact with the "flying disk", I will ask for a modification to enclose the wheels.

[Racer26]

At BMR, we had to tell quite few teams that they needed to put a guard over their shooting wheels.

GTREast didn't ask 4343 to cover their shooter wheel either. 4343's shooter uses an AM Pneumatic wheel, the exterior side of which is completely unprotected by any guards.

I would also hazard a guess that either inspectors have been doing a bang-up job catching unsafe shooters before they hit the field, or the fear-mongering from earlier in the season is largely unfounded. I haven't heard of a single incident of a shooter wheel(s) coming apart/ejecting balancing material on the field.

[Jon Stratis]

GTREast didn't ask 4343 to cover their shooter wheel either. 4343's shooter uses an AM Pneumatic wheel, the exterior side of which is completely unprotected by any guards.

I would also hazard a guess that either inspectors have been doing a bang-up job catching unsafe shooters before they hit the field, or the fear-mongering from earlier in the season is largely unfounded. I haven't heard of a single incident of a shooter wheel(s) coming apart/ejecting balancing material on the field.

All it takes is one instance for someone to get seriously hurt. I certainly HOPE we don't hear of any instances! Plus, we're more likely to see issues as these wheels get more wear and tear on them. Teams are starting to enter into their second or third event (for those teams that do more than 1 event) now, and combine champs (and District champs) into the runtime on these shooters... it could get very interesting near the end of the season, or in the offseason.

[Racer26]

I will try to poke a 3/4 inch dowel (or something similar to the diameter of a finger) into the wheel(s). If I can contact any portion of the wheel other than the actual diameter that comes in contact with the "flying disk", I will ask for a modification to enclose the wheels.

Where did this test originate? I'm honestly not sure if I agree with it or not. As I've said, 4343's shooter you would certainly have been able to touch the wheel. It runs 1:1 on a fullsize CIM, at about 35% power.

I feel like this test is probably a little excessive in terms of its reach, and I dislike the inconsistency with which the provisions of G03/R08 are being enforced with regards to shooter wheels. If FIRST and the GDC had laid out a test like this in the manual, I would have no problem with forcing teams to comply, but they did not, and inconsistency leads to teams who've passed inspection at earlier events not being passed at later events. This type of inconsistency has caused problems at Championship before where teams passed inspection at their regionals, but then failed at Championship because of inconsistently applied rules.

In my opinion, the larger concern is not to keep fingers OUT of a shooter, but keep a disintegrating shooter IN. I wouldn't say an unguarded shooter is any more or less dangerous than the unguarded drivetrains and other mechanisms that are commonplace on FRC robots.

[EricH]

Where did this test originate? I'm honestly not sure if I agree with it or not. As I've said, 4343's shooter you would certainly have been able to touch the wheel. It runs 1:1 on a fullsize CIM, at about 35% power.

2006's competitions, as I recall. Back then, it was in the Manual, or at least somewhere where it could be seen by teams with minimal effort. Lots of robots had to add guards that year...

[Brandon_L]

I will try to poke a 3/4 inch dowel (or something similar to the diameter of a finger) into the wheel(s). If I can contact any portion of the wheel other than the actual diameter that comes in contact with the "flying disk", I will ask for a modification to enclose the wheels.

I feel like a rule like this, upfront in the beginning of the season and in the manual, would clear up 99% of problems teams are having.

[Tristan Lall]

Where did this test originate? I'm honestly not sure if I agree with it or not. As I've said, 4343's shooter you would certainly have been able to touch the wheel. It runs 1:1 on a fullsize CIM, at about 35% power.
2006's competitions, as I recall. Back then, it was in the Manual, or at least somewhere where it could be seen by teams with minimal effort. Lots of robots had to add guards that year...
My recollection was that it was largely based on a suggestion implemented uniformly through the lead robot inspectors. The concern had been expressed that 2006's shooters could cause all sorts of injury, and the LRIs discussed this at length. OSHA standards were discussed, because they establish human-machine safety practices used in United States industry. (Personally, I think it was the wrong decision to conflate the human-machine contact standards used in industry with FRC robots, mainly because of the limited circumstances under which such contact can take place. It was also wrong to conflate the exploding-shooter case with the human-machine contact case. Even though the solution to both is often to install guards, it does not follow that you must install guards to protect against one when the other is present.)

Based on LRI feedback and discussions at FIRST, the standard provided by the then-Chief-Inspector was:
Shooter Shield metric - an easy metric to employ - poke around with a 3/4" dowel. You should not be able to contact any rotating or thrusting mechanisms (except when entering from the shooter "outlet").
The authority for this standard was based on those designs being deemed unsafe per <S01> (http://www2.usfirst.org/2006comp/Manual/4-The_Game.pdf):
<S01> If at any time a ROBOT’s operation or design is deemed unsafe by the head referee, it will receive a 10- point penalty and be disabled for the remainder of the match. If the safety violation is due to the ROBOT design, the head referee has the option to not allow the ROBOT back onto the field unless the design has been corrected. An example of unsafe operation is repeatedly throwing balls off the field at audience members, media personnel, judges, referees, etc. An example of an unsafe design is a shooter mechanism that has a large mass that is stopped abruptly at the end of travel and is at risk of breaking off the ROBOT and becoming a projectile.
That's an example of a good process for establishing consistency between events through rule-compliant consensus standards—even if perversely, that standard had flaws and was not always enforced consistently.

I feel like a rule like this, upfront in the beginning of the season and in the manual, would clear up 99% of problems teams are having.
The 2006 standard was a bit deficient in this respect, because the inspectors' teleconferences took place late in the build season and during the competition season. Teams were not initially advised that the LRIs were planning to use this interpretation across the board, and when confronted with it at events, teams did not always react well (understandably). This led to problems of equity, which events ended up resolving differently.

Also, there were some possible issues with the way FIRST delegated the authority to deem a robot unsafe—was that a head referee responsibility that should have been outside the purview of LRIs, or did the references to safety in the robot rules provide them sufficient authority? (FIRST also has internal procedures for delegating authority among competition officials, entirely apart from the rules. For unfathomable reasons, they don't publish these openly most years.)

[DRH2o]

As we can all see in this thread there are some serious problems with the way inspections throughout all divisions of FIRST are done. We have been to two regionals and have been 1st through inspection at a week 1 event and in the first 10 at a week 3 event. During week 1 the inspection was very quick and not very thorough -- did not measure the perimeter at all (we are 1 inch small) and looked at the floor pick-up and said it was well within the 54" ( we are about 1/4" small corner to corner ). Other components were looked at and questions were asked to the students that they answered well. At the week 3 event the perimeter was measured with a 1/4" rope with knots tied at each end -- there were several of these ropes with inspectors. 54" was not measured at all. We were weighed at 9:00am and had to wait until noon for the inspector. We were the 3rd on their list. Other teams that were passed at the same week 1 event we were at had to make major changes week 3. They agreed the changes should be made, but were confused why they were not noticed week 1. Every year I see robots on the field with bumper covers dragging the carpet and other obvious violations while other well built robots are picked over as if to try to find something wrong. I am not complaining about the inspectors, rather the process. All of the inspectors are volunteers and are doing the best they can to help everyone get on the field. There needs to be clear guidelines that are available to everyone involved.

I was talking to a frustrated inspector this past week about the way they did inspections -- 65 teams were put into blocks of ~12 teams and 2 inspectors had a block. He suggested an "express line" for teams that had passed at a previous regional. There could be a central database that includes weight, size and photo. If these all match between events and inspection is done early ( indicating no time for changes ) then a quick recheck is done to allow inspectors to be free for more involved situations. This is not my idea, but I like it. What do other inspectors think?

[Al Skierkiewicz]

Dan,
Every robot will get an full inspection at every event for several very important reasons. The first is many teams make changes that don't show up until the next event. Not all inspectors are created equal (as hard as we try to train them) and somethings get missed. There are changes to the interpretation of certain rules and there is always confusion between event staff and teams and the way the understand the rules. I can guarantee that every week some team will think outside the box and come up with a solution that does not fit the strict interpretation of the rules.

Dana is referencing the UL Standard Finger test. This was first employed in the regolith year where many teams decided to use fans and props for propulsion. what inspectors and all staff are concerned about is simply safety. We don't want anyone to lose a finger because they could stick it into a rotating device. We certainly don't want any injury due to flying debris. If in the opinion of the staff, your robot poses a threat for either of these, you may/should be asked to correct the problem. As a conscientious robot builder, you should have come up with the solution prior to your event. You don't want to injure any of your students or mentors, do you?

[Gregor]

Is this test being instructed to be conducted at all events, at some events, or only to certain robots that are suspected of being an injury risk?

[Racer26]

Like Gregor, I don't think the issue anyone is taking is with the need to be safe
The issue is the lack of a standard test decreed by HQ and laid out in the manual.

[Phyrxes]

To the best of my knowledge all teams using wheeled shooters at Virginia last weekend were asked to cover their wheels. This caused parts requests for plastic/cardboard to create covers for teams to be the most common request on Thursday. Fortunately most (55/65) robots had passed inspection by Thursday evening so this wasn't a huge issue.

[akoscielski3]

First off, has anyone posted this question in Q&A yet? If no it should be done because we NEED to know, the teams need to know if we need to add a gaurd ans the inspectors need to know if they have to have s gaurd or dont need one.

In my opinion, since it doesnt say anything anout it specifically then we dont need it to be legal. Teams didn't need them last year did they? Why do we need them this year then?

[Racer26]

In my opinion, since it doesnt say anything anout it specifically then we dont need it to be legal. Teams didn't need them last year did they? Why do we need them this year then?

It comes down to the interpretation of G03/R08 by different inspectors. Unless HQ is going to decree a test in a team update, it won't be consistent.

[pyroslev]

I imagined any team that went to a previous week regional would have been able to shortcut things a bit but seeing the explanation that makes sense. Could a remedy to that be that when teams going to further events the Robot Inspectors sign the bag form with a copy of the inspection sheet? If not this season, then next season. I imagined the teams that went to previous events could inspected by noon at least if this were implemented.

Two points of concern from what I saw of the inspectors/teams at the
Virginia Regional.

1. Bumpers: The inspector stated one team need vertical supports added to the frame on the grounds that they could not been unsupported vertically more than 8" from the corner. A quick skim of the rules and nothing mentioning vertical supports in this fashion was in the rules. I found the same on the inspection checklist. Supports were added horizontally at their insistence and to prevent bumpers breaking again.

2. Wiring: I had a large number of teams come to the Tech Support table with symptoms of radio drop outs well into Saturday. Their radios were not wired into the regulated 12v port on the Power distribution board. They were either into the non-regulated section of the board or the regulated 5v port. This concerns me as these teams had either passed inspection or had been partially completed. I estimate I diagnosed 6 teams for wiring that shouldn't have passed inspection otherwise. Others diagnosed teams as well. As many as a quarter of the teams at the Virginia Regional had miswired radios.

In the coming weeks of regional and championships, please make sure you check the wiring on your radio. I hate that we're in the 4th week and radio wiring persists like this.

[Siri]

First off, has anyone posted this question in Q&A yet? If no it should be done because we NEED to know, the teams need to know if we need to add a gaurd ans the inspectors need to know if they have to have s gaurd or dont need one. In my opinion, since it doesnt say anything anout it specifically then we dont need it to be legal. Teams didn't need them last year did they? Why do we need them this year then?I did so several weeks ago, but the answer was (surprise), 'we're not telling'.
A:564 Due to the large number of design parameters which affect the safety of a particular ROBOT MECHANISM it is not possible to provide absolute guidelines regarding compliance with [R08]. When considering MECHANISM safety, teams are advised to consider factors such as velocity, exposure, and material ratings. The Lead Robot Inspector at each event has final authority on any ROBOT'S compliance with [R08].
This answer seems odd, given that some events are making everyone cover their wheels and others are making no one. If inspectors are getting specific guidance, could it be shared publicly? If not, has anyone noticed the patterns in design parameters, as the GDC indicates?

In the end, what you need to be legal is what the inspector requires to be legal, so you'll need them this year if the inspector/LRI. Regardless, 'it doesn't say anything specifically' probably won't fly. Remember that the nature of the average shooter is very different between 2013 and 2012: more wheels-through-boards and fewer wheels-in-boxes. Even if the actual level of danger isn't so different as that, attention to it is up this year.


Could a remedy to that be that when teams going to further events the Robot Inspectors sign the bag form with a copy of the inspection sheet? If not this season, then next season. I imagined the teams that went to previous events could inspected by noon at least if this were implemented.This is an interesting idea. But if inspectors are understandably missing issues--there's so much to check I don't know how it ever gets done--how would relying on previous checks affect the integrity of inspections? (Robots can change, and you bring up issues that have slipped through.) I think I see two basic potential results here. One, negatively because more issues slip through, particularly in the burden of early events. Two, positively, because efforts are better focused, assuming potential issues are identified in another way (without creating resentment). Interesting idea.

[Jaxom]

In my opinion, since it doesnt say anything anout it specifically then we dont need it to be legal.

The rules don't specifically say you can use pool noodles to block frisebees.... :D

I imagined any team that went to a previous week regional would have been able to shortcut things a bit but seeing the explanation that makes sense. Could a remedy to that be that when teams going to further events the Robot Inspectors sign the bag form with a copy of the inspection sheet? If not this season, then next season. I imagined the teams that went to previous events could inspected by noon at least if this were implemented.

I don't think it's a good idea to give previously-inspected robots a pass or even an abbreviated inspection. I've found issues on robots that have passed inspection at TWO regionals. If no one has ever found a problem on a robot I've inspected at that robot's next event I'd be shocked. We're human. On top of being human there are rookie inspectors, inspectors that aren't clear on [name your system], there are inspectors that are seeing their 15th robot in one day, and....

I had a large number of teams come to the Tech Support table with symptoms of radio drop outs well into Saturday. Their radios were not wired into the regulated 12v port on the Power distribution board. They were either into the non-regulated section of the board or the regulated 5v port. This concerns me as these teams had either passed inspection or had been partially completed.

I found a robot like this last year (radio in a standard 12V circuit); asked the team why they did it that way. Answer was "we wired it that way last year." Why did you do it then? "That's how we wired it the year before." I explained why they needed to be in the regulated port & got a "huh...maybe that's why we've been having comm problems for the last two years." :ahh:

[Jon Stratis]

I imagined any team that went to a previous week regional would have been able to shortcut things a bit but seeing the explanation that makes sense. Could a remedy to that be that when teams going to further events the Robot Inspectors sign the bag form with a copy of the inspection sheet? If not this season, then next season. I imagined the teams that went to previous events could inspected by noon at least if this were implemented.


This isn't satisfactory, unfortunately. Teams make changes during an event that aren't always reinspected (the team doesn't ask for a reinspection, and the change isn't necessarily obvious). The teams make hold back 30 lbs from their robot between events and make changes to that as well. Additionally, you have the trouble of inspectors missing stuff... FIRST does the best it can to train inspectors, but there simply isn't enough time available for the volunteers to be trained to a point of uniformity. So, something might get missed by one inspector, and found by another. I've seen it happen while at an event - a team passes inspection, but then another inspector finds an issue while looking at their robot in the queuing line.

Passing the inspection sheet from one event to another simply isn't going to work. And frankly, teams that have already been to an event and passed inspection once can pass it again very quickly as is - At North Star last year there were a few teams that had passed before 9:30, as they could start the process as soon as the robot came out of the bag, knowing they had passed previously and had no changes to make.

The biggest problem we have with inspections isn't getting teams to pass. It's getting teams to come up to start the inspection process early! Those who start early almost always pass early as well.


This answer seems odd, given that some events are making everyone cover their wheels and others are making no one. If inspectors are getting specific guidance, could it be shared publicly? If not, has anyone noticed the patterns in design parameters, as the GDC indicates?


As the response you quoted indicates, the decision is up to the LRI as to what constitutes "safe" on a robot. If the GDC gave the inspectors a clear-cut definition of "safe" with regards to shooter wheels, they would have given it to the teams as well. There have been plenty of threads and posts here outlining the concern over exposed shooter wheels - take a look at your mechanism and see if any of those concerns apply to you. If so, address the concern to make your robot safer... I've never seen an inspector request a team to remove a safety shield.

[DRH2o]

This isn't satisfactory, unfortunately. Teams make changes during an event that aren't always reinspected (the team doesn't ask for a reinspection, and the change isn't necessarily obvious). The teams make hold back 30 lbs from their robot between events and make changes to that as well.

Passing the inspection sheet from one event to another simply isn't going to work. And frankly, teams that have already been to an event and passed inspection once can pass it again very quickly as is - At North Star last year there were a few teams that had passed before 9:30, as they could start the process as soon as the robot came out of the bag, knowing they had passed previously and had no changes to make.

This is the reason for the database with weight and picture. If my robot weighs the same as it did two weeks ago then nothing has been changed -- most likely.

"And frankly, teams that have already been to an event and passed inspection once can pass it again very quickly as is "

If the inspectors know to get to them --- express line -- they still get inspected and things missed will be checked.

[Jon Stratis]

This is the reason for the database with weight and picture. If my robot weighs the same as it did two weeks ago then nothing has been changed -- most likely.

"And frankly, teams that have already been to an event and passed inspection once can pass it again very quickly as is "

If the inspectors know to get to them --- express line -- they still get inspected and things missed will be checked.

We don't deal with "most likely"'s. If a team makes a small wiring change, it won't show up on the scale... but it could have serious side effects. If a team removed their shooter to use on their practice bot and then put it back on, it won't show up on the scale... but they may have attached it wrong and it's sticking outside their frame perimeter now. Weight isn't everything, it only indicates big changes that were made, not small ones. And all it takes is one small change to short a wire to your chassis or have your robot die on the field.

Inspectors know to get to them when the team comes up and tells us they're ready to be inspected. I've always seen inspections handled on a "first come, first served" basis - whoever comes up first gets an inspector in their pit first. The teams who have already been to a regional and been inspected should be the first ones in line, but often they (and a lot of other teams) lollygag around and don't come up to inspections, causing a delay themselves. The concept of an "express line" would give teams fortunate enough to attend multiple events a larger, unfair advantage over other teams who may be ready for inspections at that particular event first.

[pyroslev]

The biggest problem we have with inspections isn't getting teams to pass. It's getting teams to come up to start the inspection process early! Those who start early almost always pass early as well.

Not every regional does it all the same way. At Virginia, teams were inspected in the pits and weighed at inspection to my knowledge.

If FIRST could create a protocol, not even a data base, where teams that had been to previous events, could receive an cursory inspection on load in night. If the Inspectors at that previous event can sign the lock up form, they can do a quick once over and put a copy of the sheet into the bag.

The reason I say during load in is that I've seen enough robot inspectors present to at least try this. If 10 teams were previously at events, let's say 5 do early load in. Things should be calm enough to get a few of them checked out, freeing them up for teams that need a more serious look over.

To ensure things are above board, the inspectors can do a final check before they are allowed to compete in matches, in the event teams do major work.

I say all this because 3 practice matches were skipped by the field in a row cause teams were too nervous to miss an inspection and no teams were qualified to be in the filler line, as they have to pass inspection to be in the filler.

Just my two pieces of copper.

[Jaxom]

Not every regional does it all the same way. At Virginia, teams were inspected in the pits and weighed at inspection to my knowledge.

This is how every inspection I've ever been part of is done. Typically we start with weight & size; hence the "come up to inspection" to start.

If FIRST could create a protocol, not even a data base, where teams that had been to previous events, could receive an cursory inspection on load in night. If the Inspectors at that previous event can sign the lock up form, they can do a quick once over and put a copy of the sheet into the bag.

As several of us have said, there's no "cursory inspection" we can do. Besides, this would change checking in on Wed from a traffic reduction exercise to something that some teams could use to get more time with their robots on Thursday.

To ensure things are above board, the inspectors can do a final check before they are allowed to compete in matches, in the event teams do major work.

Inspections are always supposed to be done after changes; this doesn't do anything to reduced the delays on Thursday.

[Tem1514 Mentor]

At BMR, we had to tell quite few teams that they needed to put a guard over their shooting wheels.

And did you have any team(s) required to put guards over the drive system?

[pyroslev]

This is how every inspection I've ever been part of is done. Typically we start with weight & size; hence the "come up to inspection" to start.

I didn't know that first part so my bad. I've never been with my team when they inspected as student or mentor. I've been volunteering or scouting.

Inspections are usually slow (more so with 65 teams), I've gotten used to that. So many teams don't go over their robot with the list. To any team still sitting there with a bagged robot, check it over again best you can while it's in the bag.

My biggest things from the technical support side is make sure your radio, CRIO and cameras are wired correctly.

[DRH2o]

We don't deal with "most likely"'s. If a team makes a small wiring change, it won't show up on the scale... but it could have serious side effects. If a team removed their shooter to use on their practice bot and then put it back on, it won't show up on the scale... but they may have attached it wrong and it's sticking outside their frame perimeter now. Weight isn't everything, it only indicates big changes that were made, not small ones. And all it takes is one small change to short a wire to your chassis or have your robot die on the field.

Inspectors know to get to them when the team comes up and tells us they're ready to be inspected. I've always seen inspections handled on a "first come, first served" basis - whoever comes up first gets an inspector in their pit first. The teams who have already been to a regional and been inspected should be the first ones in line, but often they (and a lot of other teams) lollygag around and don't come up to inspections, causing a delay themselves. The concept of an "express line" would give teams fortunate enough to attend multiple events a larger, unfair advantage over other teams who may be ready for inspections at that particular event first.

Okay -- don't want to get into a debate, but. I never said they would not get inspected. Exact weight is an indicator of no change. Practice bot -- most of us do not have that luxury, but incorrect instalation would be corrected if found to be a problem.....

You need to be aware of how every regional operates before making assumptions. We get wieghed before 9:00am and have to wait until after noon to get inspected in our pits because of teams having problems passing that have not been inspected before -- there is a problem with that.

The fact is that the inspection process is flawed and needs to be fixed -- I do not have the answers, but was passing on suggestions made by a very good inspector at our regional. This system could work. People just need to be open to admitting that what is being done is not working well.

[Jon Stratis]

Okay -- don't want to get into a debate, but. I never said they would not get inspected. Exact weight is an indicator of no change. Practice bot -- most of us do not have that luxury, but incorrect instalation would be corrected if found to be a problem.....

You need to be aware of how every regional operates before making assumptions. We get wieghed before 9:00am and have to wait until after noon to get inspected in our pits because of teams having problems passing that have not been inspected before -- there is a problem with that.

The fact is that the inspection process is flawed and needs to be fixed -- I do not have the answers, but was passing on suggestions made by a very good inspector at our regional. This system could work. People just need to be open to admitting that what is being done is not working well.

Above bolded for emphasis... you should also be aware of how every regional operates as well - from what you've described earlier, the process you saw at your regional is very different from the process I've seen at other regionals (Kansas City, St. Louis, 2 in Duluth, 2 in Minneapolis, and Champs).

We can't implement any sort of "express lane" or early inspection solely for those teams that had been at a previous regional. It would give them an unfair advantage, allowing them more time on the field during the practice day than other teams who might have been just as ready for inspection but didn't have the benefit of a previous competition. The only fair way to handle inspections is on a first-come, first-served basis, which is the only process I've actually seen employed.

We've also pointed out the difficulties with allowing inspections to "carry over" from one event to the next - there's a very good reason for requiring a full inspection at every event.

I certainly am up for hearing (and passing on) suggestions that can improve the inspection process... But we can't sacrifice fairness for all teams or potential safety issues at the event just to make it easier for teams to get through inspection at their second event, or to reduce headaches from inspectors missing something the first time and catching it the second.

[Alan Anderson]

Exact weight is an indicator of no change.

Exactly matching weight at two different regionals is an indicator of something fishy. :p

We get wieghed before 9:00am and have to wait until after noon to get inspected in our pits because of teams having problems passing that have not been inspected before -- there is a problem with that.

If those teams with problems got into the inspection queue before you did, then I think it's perfectly reasonable for them to get inspected before you do. The underlying problem isn't one of priority, it's one of manpower. You want the inspections to go faster? Volunteer to be an inspector.

[Tristan Lall]

Inspection procedure varies from event to event, and year to year. Lead inspectors do share best practices, but the exact procedures will definitely vary, depending on numerous factors.

When in charge of inspections, I consider equity as being more important than priority, at least in terms of ensuring that all robots are able to compete. However, inspectors don't necessarily have the resources to evaluate either one in any comprehensive sense. Demonstrate a greater need for inspection (e.g. by showing up unfinished) and you may be seen by more inspectors, more often than the team that showed up to be weighed first. One priority-driven consideration is access to the practice field—and at least in that respect, promptly visiting the inspection station is likely to work in your favour.

Also, because of limited resources and uncertainty about teams' individual needs, inspections tend to be organized around efficient use of inspectors' time, rather than efficient use of teams' time. And even then, different inspectors spend different amounts of time for different reasons.

This means that on a practical level, FRC inspection is not currently a deterministic process, and you can't expect that it will operate like a priority queue. (As for whether or not it should be a strict priority system, that's worth further discussion.)

[dtengineering]

To concur with much of what has been said above:

Every robot needs a full inspection at every event. In Atlanta, I once had the opportunity to explain to a team (who had previously passed inspection at two regionals) what a pressure relief valve was, and why it was an important part of the pneumatic safety system. They found the part in their toolbox, said, "Oh... so THAT's what THIS is! Thanks!" and put it on their robot. Then we discussed bumpers, which they also fixed... although that took a bit more effort. But they had passed inspection without the valve or proper bumpers twice previously.

Secondly, there IS an unofficial priority queue at most events I've been to... but the priority isn't for teams who have been to a previous event, it's for teams who are organized, have followed the rules, and did their own tech inspection prior to bagging/shipping their robot. All they need to do is send a representative to the inspection station early Thursday morning and say "Ready whenever you are." They'll have priority over all the teams doing last minute repairs and modifications and saying "Not yet! Not yet!"

Finally, and I don't think I can stress this enough... inspectors want to see teams pass inspection. Teams need to know that if they need help, they should also request an early inspection.... one year during an early inspection I identified a problem that was going to be very difficult for the team to solve (at least not in a way that would make them happy), so I was able to discuss it with a few other inspectors over lunch. I figure that between the inspectors at the table we had probably built at least 30 FRC robots between us. We batted around a few ideas and then someone suggested a brilliant solution that while "out of the box" was still within the rules. I took the suggestion back to the team, they implemented it, and darned if the solution wasn't cited as part of one of the awards that they won. Had we found the problem at 5:00 on Thursday afternoon, it would have been a much... less happy... outcome.

Jason

Edit: One more example... at GTR once, after previously having passed inspection in Portland, we got called for having a pneumatic cylinder that was either 1/2" long or 1/2" short... our spares were all in Vancouver. Tristan <yep... same guy who made the previous post!> was the LTI and while he was quite clear that we couldn't use an illegal cylinder, he was also on his phone to his buddy at the pneumatics supply shop and had a legal replacement waiting for us (at a nice discount) in about half an hour. I'm glad we were inspected in the morning, and not in the late afternoon! I still use that as my personal example of how inspection "should" work.

[bhughes]

Per R24-A, is it legal to also have a metal backing along with wood, so long as it abides by R24-A and R29-B?

We're having arguments inside the team about what the rules say. I don't think its legal, but it'd be really nice if it was.

[EricH]

Per R24-A, is it legal to also have a metal backing along with wood, so long as it abides by R24-A and R29-B?

We're having arguments inside the team about what the rules say. I don't think its legal, but it'd be really nice if it was.

If you look at Figure 4-4, it shows an optional "backing"--though it's more of a clamping system for fabric--that is metal. However, I caution you that R24 (no subpart) and Figure 4-4 combine to bar any other type of metal backing (and note Al's comments on the heavy stuff inspectors have been telling teams to pull out of bumpers, as well--he is, after all, the lead lead robot inspector).

In my opinion, your opinion is correct.

[bhughes]

If you look at Figure 4-4, it shows an optional "backing"--though it's more of a clamping system for fabric--that is metal. However, I caution you that R24 (no subpart) and Figure 4-4 combine to bar any other type of metal backing (and note Al's comments on the heavy stuff inspectors have been telling teams to pull out of bumpers, as well--he is, after all, the lead lead robot inspector).

In my opinion, your opinion is correct.

How exactly do they bar any other type of metal backing though? I'm not sure how they exclude any such thing.

[Jaxom]

How exactly do they bar any other type of metal backing though? I'm not sure how they exclude any such thing.

Because the rule says: "BUMPERS must be constructed as follows," and then lists a very limited set of very specific things. There's nothing there about "optional metal backing." Also note that the optional metal angle is required to be aluminum.

[Mike Betts]

...The fact is that the inspection process is flawed and needs to be fixed...

Dan, et al,

You are an 8th year veteran mentor on an 8th year veteran team. I am quite sure that your students can handle pit duties quite well without you hovering over them...

Volunteer to be an inspector. Your knowledge and insight will be valuable to the community (especially the rookie teams).

Bottom line: You can be part of the solution if you choose to be...

How's this for a suggestion:

<Soapbox>

Every team with greater than 3 years experience donates a mentor on Thursday to help with the inspection process. If you are not a technical wizard, OK. You don't need a Masters in engineering to weigh a robot or measure a set of bumpers.

Think of a 60 team regional with 40 or 50 inspectors. Waiting would be negligable and rookies would receive undivided, top-shelf support. And when the inspectors return to their teams, they take that experience back with them (even veterans can learn)...

</Soapbox>

Regards,

Mike

[Ben Martin]

Bumper question for Al and the rest of the inspection community:
When creating the "rigid fastening system" specified in R24-E with brackets, would you be required to use smaller connection brackets like Andy sells here (http://www.andymark.com/product-p/am-2448.htm), or could you have one continuous piece of attachment material stretching across the frame? I am seeing questions about metal backing on bumpers, and I was curious how inspectors would determine legality if the "rigid attachment system" was a continuous bracket running along the frame for 17+ inches.

[FrankJ]

The bumpers are weight limited to 20lb. With this years smaller frame perimeter that still leaves a lot for a "robust" connection. At some point though I would think it would become a flag to see what other rules you are pushing the limits to.

[JVN]

Because the rule says: "BUMPERS must be constructed as follows," and then lists a very limited set of very specific things. There's nothing there about "optional metal backing." Also note that the optional metal angle is required to be aluminum.

Actually, they say quite a bit more. Paraphrasing rules can be extremely counter-productive in discusssions like this.

Those playing the home game can check out the full manual here:
http://frc-manual.usfirst.org/viewItem/181
Do a ctrl-F for "4.1.6" and read from there

Check out R24E:
Bumpers must attach to the FRAME PERIMETER of the ROBOT with a rigid fastening system to form a tight, robust connection to the main structure/frame (e.g. not attached with hook-and-loop or tie-wraps). The attachment system must be designed to withstand vigorous game play. All removable fasteners (e.g. bolts, locking pins, pip-pins, etc.) will be considered part of the BUMPERS.

This rigid fastening system which is openly listed as a legal part of the bumper is not defined, anywhere. Nowhere. Not anywhere.

So it seems to me that as long as this fastening system fulfills all the other rules regarding bumper construction (the big ones being overall weight, and protrusion distance beyond the robot frame) then teams are allowed to do quite a bit creatively.

If you think back a few years, this fastening system was much more defined. The GDC (I believe) intentionally opened up the rules a bit, not only to make the rules simpler, but also to allow teams more room to do whatever attachment methods they want.

As long as the bumpers weigh less than 20 lbs, are rigid enough to survive competition, follow the construction rules which heavily define the outside face of the bumpers and don't have attachment (hard) parts that stick out too far -- does it matter what the construction is?

-John

[artdutra04]

Exact weight is an indicator of no change.Not quite. You can take off exactly 3.00 lbs of one mechanism and replace it with 3.00 lbs of a different mechanism.

I have also seen robots that have had exactly no physical changes made (except for code revisions) weigh anywhere between 0.1 and 0.4 lbs different between events.

[FrankJ]

I have also seen robots that have had exactly no physical changes made (except for code revisions) weigh anywhere between 0.1 and 0.4 lbs different between events.
Today 11:10 AM

I have often wondered what software weighs.

[blayde5]

To address people's concerns about bumper legality during matches,

During eliminations, we had at least the lead robot inspector behind the field with the volunteers ready to re-inspect any robots as well as make sure they were compliant during the match.

Some times, the head ref would catch something that we couldn't necessarily catch during inspection (for example, one robot was tearing up the field due to its pick-up mechanism) and ask us inspectors to rectify it or at least investigate it before the team took their robot off the field.

I myself was behind the field with the rest of the volunteers quickly making sure there wasn't any obvious flaws that teams missed as an inspector (bumper fabric dragging on the ground, new mechanisms that hadn't been inspected, etc.) A lot of teams had made changes during eliminations to add a new mechanism and those had to be re-inspected quickly before their next elimination match.

Moral of the story: feel free to make changes to your robot, just make sure that they're compliant and then please find an inspector well before your next match starts so we can re-inspect it

[Jaxom]

Actually, they say quite a bit more. Paraphrasing rules can be extremely counter-productive in discusssions like this.

Maybe, but it can also make posts shorter. ;) But in any case, that's not a paraphrase; that's a direct quote, except for adding emphasis to "must". I'd hope that anyone that's concerned about this particular debate has a copy of the rules at his or her fingertips and could read the parts I didn't include.

The question I was answering was "how can you exclude metal backing?" Having the rule written the way it is allows a logical way to do that, and that's all I was trying to say.

As long as the bumpers weigh less than 20 lbs, are rigid enough to survive competition, follow the construction rules which heavily define the outside face of the bumpers and don't have attachment (hard) parts that stick out too far -- does it matter what the construction is?

Apparently, yes:
There are some nice drawings that are part of the rule, in particular Figure 4-4. However, please note, the pool noodles and the bumper rules do not allow for the addition of weight to increase the overall weight of the robot. You may not add steel rod, brass, shot or other high mass material to the interior of the pool noodles. Also note that the optional angle stock shown in Figure 4-4 is specified as aluminum. If your bumpers are modified in a such a way, please be prepared to remove the additional weight at your event.

I think we're well into the "lawyering" of the rules that we've been encouraged not to do. I'm having trouble coming up with a reason to add metal backing to the bumpers for any reason except to add weight. Please share if you have something else in mind.

[ebarker]

I have often wondered what software weighs.

One Strawberry.

[Mk.32]

I have often wondered what software weighs.

I would rather think it's just the scales being calibrated differently/error within the scales.

[Tristan Lall]

I think we're well into the "lawyering" of the rules that we've been encouraged not to do. I'm having trouble coming up with a reason to add metal backing to the bumpers for any reason except to add weight. Please share if you have something else in mind.
Al is describing a situation that comes up every so often, where a team will hide something heavy within the cushion of the bumpers (to adjust centre of mass or increase total mass). If there's no pretense of making it part of any of the elements described in the rules, then it's not allowed.

What he's not saying is that those materials are inherently prohibited in all possible bumper applications.

Teams use enormous aluminum angle to add weight. Teams use heavy fasteners and brackets to add weight. There is no rule against adding weight, and if teams comply with all the other rules, it's legal.

[JVN]

Al is describing a situation that comes up every so often, where a team will hide something heavy within the cushion of the bumpers (to adjust centre of mass or increase total mass). If there's no pretense of making it part of any of the elements described in the rules, then it's not allowed.

What he's not saying is that those materials are inherently prohibited in all possible bumper applications.

Teams use enormous aluminum angle to add weight. Teams use heavy fasteners and brackets to add weight. There is no rule against adding weight, and if teams comply with all the other rules, it's legal.

That is my interpretation, also.

The undefined rigid fastening system can be a heavy, rigid fastening system, as long as no other rules are violated.

I'm not clear if Al is saying something different. I'm also curious if there is an official interpretation other than Al on the forum. I saw someone submitted a Q&A which touches on the subject.

-John

[Alan Anderson]

I have also seen robots that have had exactly no physical changes made (except for code revisions) weigh anywhere between 0.1 and 0.4 lbs different between events.

At the Championship in St. Louis last year, it wasn't unusual to see a robot weight change by several tenths of a pound based on how people were standing around it. I think the air movement in the convention center was strong enough to put noticeable force on the scale when it came from directly above.

[EricH]

That is my interpretation, also.

The undefined rigid fastening system can be a heavy, rigid fastening system, as long as no other rules are violated.

-John

Aye, but here's the thing: He wasn't asking about a fastening system. He was asking about a backing system. Now, to me at least, the way the question was put indicates wanting to put a nice large piece of metal behind the plywood, in addition to the fastening system. Not as the fastening system, but in addition to it.

So, here is a question for you to answer (and may you have the right answer as the inspectors): If there is a heavy piece of metal, that serves no purpose in the fastening system or the bumper, and it is attached to the bumper, is it legal or illegal? Assume for the sake of discussion that the fabric is clamped using an obvious system not involving said piece of metal.

[FrankJ]

So, here is a question for you to answer (and may you have the right answer as the inspectors): If there is a heavy piece of metal, that serves no purpose in the fastening system or the bumper, and it is attached to the bumper, is it legal or illegal? Assume for the sake of discussion that the fabric is clamped using an obvious system not involving said piece of metal.

If it served no purpose to the fastening system, (just there to add stiffness / weight.) I would say that it is not legal. If it is an integral part of the fastening system then you have a good argument for it being legal regardless of the side benefit.

A side story, In the way back days of show room stock car racing. Some people came up with the idea of attaching the roll bars in such a way to make the chassis stiffer. (Bob Sharp cars driven by Paul Newman if memory serves me correctly) Competitors complained until they did the same thing to their cars. I am not trying to equate that to putting metal rods in bumper noodles.

[Al Skierkiewicz]

OK,
Let me try to restate this. Teams regularly come up with unusual bumper designs, some are legal and some are not. It is legal to add aluminum plate to the back of a bumper system to aid in easy mounting of the bumper to the frame. These are most often used in one piece bumper designs. The backing plate is also used to strengthen the bumper in addition to mounting. Backing plate is limited of course by the gap rule. 1/2" plate would obviously violate the bumper rules.
If the team adds something to the bumper to satisfy the supporting structure part of R29, then that weight is required to be part of the robot weight and not the bumper weight. The LRI at each event is trained to make that determination.
The illegal addition of weight which I stated earlier violates several parts of the bumper rules including the hard parts distance limit and unmodified pool noodles.
As to variations in weight. Depending on the materials in use on the robot, humidity plays a significant role from event to event. Also while it wouldn't seem possible, concrete floors do have some flexibility and therefore standing near to the scale can affect it's accuracy. That is why teams should be asked to step back from the scale during weighing. Scales are also somewhat temperature sensitive and so significant cold drafts at floor level can also affect readings. Inspectors should be aware of these variables and know how to accurately measure the weights of all robots. Calibration is checked at minimum every day with known 25 lb. standard weights.
BMartin, I hope this answers your question.
Everyone, a committee was formed last summer to investigate the bumper rules and try to make them easier to understand, more open to design and construction, better for rookies and in general to make it easy for all teams. The result was a recommendation to the GDC which accepted the report and incorporated that into the 2013 rules. Inspectors, veteran mentors and rookie mentors all had input.
On a personal note...I do not like ugly bumpers. I don't like to see flaps hanging down, bumpers that are crooked on the frame or have a sloppy mounting. Teams spend so much time making beautiful machines that look good in print and on TV. Why would you want that image spoiled by an ugly bumper system?

[Al Skierkiewicz]

OK,
Time to start thinking about the Championship and how your robot stand in terms of inspections. Every year we will find robots that had something sneak through in inspections, something missed by a new inspector or something added without being reinspected. So from here on, we will discuss some of those problems that we have seen this season and remind teams of some of the rules and how they are being enforced.

1. If I had a nickel for every time I heard "But we passed at XXXX regional" I would have retired a long time ago. We will find things that other events may not have. Sorry, but you are in the Big Show and everything will come under scrutiny.
2. Bumpers have not been the issue they have been in the past. The bumper committee hopes the new rules have helped with that. However, everyone really likes to see at nice looking robots. Please insure that your bumper covers look nice and don't drag. Strictly interpreted, the cover that hangs down to the floor is out of the bumper zone. I have seen several robots run over the covers while in match play. Please don't be one of them.
3. Frame perimeter issues should be all fixed by now but we will still check every robot.
4. Virtually of all of the later season events have had robots changing design or function throughout the weekend. I expect Champs to be the same. There are rules that limit your changes. A team can make design improvements whenever the pits are open. These modifications are viewed as improving robot function. However, if the improvement requires you to remove robot mechanisms in order to make weight, you may not return to the original design. This violates the rule that requires all mechanisms to be weighed at the same time. If the additions and robot are under the 120 lbs when weighed together, then the mechanisms are considered interchangeable and can be removed from match to match.
5. Make sure you have your Bag and Tag form handy when you enter the venue. I will have inspectors stationed in the pit aisles to make this a quick process. If your forms are not with the robot, make sure that one of the adults coming into the pits on Wednesday afternoon has the form. The one thing I don't want to do is hold up your opening while we get all the forms filled out. I don't know if the Head Refs will be reachable on Wednesday.

The division Lead Robot Inspectors will be Chuck Dickerson, Chris Paulik, Ed Sparks and myself. Jeff Pahl will miss this year but will hopefully return next year.

As an important note for teams using pneumatics. The robot rules are very specific as to the use of compressors. There may be one and only one KOP or equivalent compressor used to pressurize the robot. The compressor may be on board or off board but not both. You may not use a separate legal compressor to fill that tanks than the one you use on the robot. You may not use a shop compressor to fill the robot, ever. Head refs have been watching these practices. At a minimum, they may release stored pressure prior to the match starting. Please plan accordingly.

Until next time...

[CalTran]

OK,
2. Bumpers have not been the issue they have been in the past. The bumper committee hopes the new rules have helped with that. However, everyone really likes to see at nice looking robots. Please insure that your bumper covers look nice and don't drag. Strictly interpreted, the cover that hangs down to the floor is out of the bumper zone. I have seen several robots run over the covers while in match play. Please don't be one of them.


Quick random question about bumpers Al: What's the lightest full set of bumpers you've ever seen? We got inspected at Razorback with a full set of bumpers that weighed in at ~7.5lbs and shocked a great deal of inspectors with bumpers that defied all other bumper physics...our robot has a 108" perimeter, with a, IIRC, 14" gap somewhere and the rest is bumper. The color change for us was one of those nifty |-- shaped fabric covers where you lift it one direction or another for color.

[MechEng83]

What's the lightest full set of bumpers you've ever seen?

Our bumpers are the minimum size 8" corners. A full set (4 of them) weighed in at 7.1 lbs for each of our regionals. We have seperate red and blue sets, so we probably save weight over you by having less fabric. The attachments to the frame are some small aluminum c-channel brackets.

[Al Skierkiewicz]

7.5 lbs is about the lowest weight I have inspected this year. With the need to just cover the exterior corners, several were under ten pounds. However, the type of plywood used really is the determining factor. One team was nearly 18 pounds and was using exterior furniture grade 17 ply plywood. With all the resin and weather protection, the plywood is heavy. Anything over 15 lbs get a long look by inspectors to determine if any illegal weight has been added to pool noodle interiors.

[Andrew Lawrence]

Our bumpers are 90% full (cover everything but a few inches on the front and back of the robot), and a set of them is about 7.2 lbs. We used the normal 3/4" plywood and fabric. It's strong plywood and has never broken for us.

Is this normal?

[Jon Stratis]

I just checked for my two regionals... at Lake Superior, we had one set of bumpers that was 6.0 lbs, and at North Star a set that was 6.2 lbs. I can only imagine that both of those sets were corner-only bumpers!

[CalTran]

See, that's the thing - ours aren't corner only bumpers. I'll get the exact measurement tomorrow, but I believe we had somewhere around 90"-95" of bumpers, all your standard plywood regulation size.

[Al Skierkiewicz]

OK, some teams failed to bag their robot at their last event expecting to not get an invitation. Now that the invitation has arrived (and you have shipped your robot) this is a little bit of an issue. For all of those teams finding themselves in this situation, you need to contact FRC if you have not done so, to let them know. In addition, you will still need your B&T forms with you when you arrive.

[Wayne Doenges]

OK, some teams failed to bag their robot at their last event expecting to not get an invitation. Now that the invitation has arrived (and you have shipped your robot) this is a little bit of an issue. For all of those teams finding themselves in this situation, you need to contact FRC if you have not done so, to let them know. In addition, you will still need your B&T forms with you when you arrive.

Ooops :ahh:

[Al Skierkiewicz]

I should add that if you did not bag your robot before putting it in a crate, then do not open it in St. Louis. Please see the LRI for your division when you load in your pit on Wednesday or Thursday. He will have specific info for you and will direct your team as how to proceed.