Al's Annual Inspection Thread 2015

[GaryVoshol]

Originally Posted by Richard Wallace

I agree this "change" is going to make a lot of work that (IMO) should not be necessary, both for volunteers and competitors. The veneer is wearing thinner every year on the myth of six week build.

So a team has a 4-match turn-back and decides to make a change. 2.5 matches in, they get it done and now expect the inspectors to do the re-inspection. In time for their match. Right.

And, as soon as a team starts making modifications, an inspector should tell the head ref that their sticker is null and void. If they come out without the LRI confirming re-inspection, the whole alliance gets a Red Card. Ouch.

[AdamHeard]

Originally Posted by GaryVoshol

So a team has a 4-match turn-back and decides to make a change. 2.5 matches in, they get it done and now expect the inspectors to do the re-inspection. In time for their match. Right.

And, as soon as a team starts making modifications, an inspector should tell the head ref that their sticker is null and void. If they come out without the LRI confirming re-inspection, the whole alliance gets a Red Card. Ouch.

Oh boy....

As an inspector, I prefer to go out of my way to give the kids a good experience, not look out for opportunities to yell "Gotcha! Red card!"

[rich2202]

If I were an RI, and a team told me they planned to switch between Part A and Part B, I would have them weight with Part A, and then Part B, and note the weights next to a description of the part.

Then, when they came for subsequent reinspections, I would look for the part, check their weight, and if everything seems in order, note which is the current configuration/date/time, and clear them for competition.

That way, we know which is their last configuration when inspected, and if they show up on the field with the wrong configuration ... it is their problem.

[GaryVoshol]

Originally Posted by AdamHeard

Oh boy....

As an inspector, I prefer to go out of my way to give the kids a good experience, not look out for opportunities to yell "Gotcha! Red card!"

No intent of Gotcha whatsoever. In fact, this would be preventing the other 2 teams in the alliance from getting a Red Card, since they have absolutely no way of knowing that the transformer team's inspection was temporarily suspended. If the LRI and HR keep in constant communication, the Red Card will be avoided, not made easier to get.

[EricH]

Originally Posted by GaryVoshol

No intent of Gotcha whatsoever. In fact, this would be preventing the other 2 teams in the alliance from getting a Red Card, since they have absolutely no way of knowing that the transformer team's inspection was temporarily suspended. If the LRI and HR keep in constant communication, the Red Card will be avoided, not made easier to get.

Aye. If a team isn't re-inspected, and this is known BEFORE the match, the OTHER side of T8 comes into play--the team doesn't participate in the match, including their HP. This gives only the team in question a Disqualification (Section 5.5.3, Part D) which assigns no points, rather than a red card. (A Red Card is a Disqualification, but a Disqualification is not necessarily a Red Card.)

And I agree, we're not out there to "Gotcha" teams. If it's a quick fix, I'd rather have the team fix it quickly than apply any sort of DQ or RC--just works out better.

[Al Skierkiewicz]

So here is the next edition of the list (based on the first two weeks)...
1. Please make sure you have your Bag and Tag paperwork with you when you drop your robot off for your event. Inspectors want to check it for accuracy prior to letting you open the bag and begin work at your event. If it is in the bag (not visible), in your mentor's back pocket (who is not coming) or on the workbench back at your build space, it is going to invoke a delay while we process the non-compliance form. Attaching it to the bag with a big, double handle paper clip works very well.
2. Teams have been bagging their robot with the battery in the robot and connected. This is pretty dangerous practice. When packing your robot for the next event, do not put your battery in the robot, please.
3. Inspectors need to see the electronics during inspection. Do not hide them or cover them with conformal coatings. Mounting them upside down is also difficult to inspect and unreliable for operation.
4. You must have the latest firmware installed on your robot. Under the current version of Inspection checklist, these are the versions you should have.
Driver Station – 08021500 or newer <R80> (Note the version number is a date in the format of, DD/MM/YY00)
roboRIO – v23 and 2.1.0f3 <R45>
Talon SRX – v.28 for PWM, v1.01 for CAN <R41, R59>
Jaguars – v109 <R59> for CAN
PCM – v1.62 <R60> if pneumatics are used.
PDP – v1.37 <R61>
Yes this is a repeat, but many of you didn't listen in week 2. The PDP CAN must be connected to the RoboRio CAN.
5. There are two fuses in the PDP. While they may appear to be fully inserted, they are often not. Please be sure to push them down firmly. The top of the fuse should be nearly the same height as the Weidmuller connectors that are mounted next to each one. When not fully inserted these to become intermittent, resetting the radio and/or the RoboRio.

As always, ask your LRI if you have any questions. Do not assume you know the answer. Good Luck everyone.

[ATannahill]

Originally Posted by Al Skierkiewicz

So here is the next edition of the list (based on the first two weeks)...
1. Please make sure you have your Bag and Tag paperwork with you when you drop your robot off for your event. Inspectors want to check it for accuracy prior to letting you open the bag and begin work at your event. If it is in the bag (not visible), in your mentor's back pocket (who is not coming) or on the workbench back at your build space, it is going to invoke a delay while we process the non-compliance form. Attaching it to the bag with a big, double handle paper clip works very well.
2. Teams have been bagging their robot with the battery in the robot and connected. This is pretty dangerous practice. When packing your robot for the next event, do not put your battery in the robot, please.
3. Inspectors need to see the electronics during inspection. Do not hide them or cover them with conformal coatings. Mounting them upside down is also difficult to inspect and unreliable for operation.
4. You must have the latest firmware installed on your robot. Under the current version of Inspection checklist, these are the versions you should have.
Driver Station – 08021500 or newer <R80> (Note the version number is a date in the format of, DD/MM/YY00)
roboRIO – v23 and 2.1.0f3 <R45>
Talon SRX – v.28 for PWM, v1.01 for CAN <R41, R59>
Jaguars – v109 <R59> for CAN
PCM – v1.62 <R60> if pneumatics are used.
PDP – v1.37 <R61>
Yes this is a repeat, but many of you didn't listen in week 2. The PDP CAN must be connected to the RoboRio CAN.
5. There are two fuses in the PDP. While they may appear to be fully inserted, they are often not. Please be sure to push them down firmly. The top of the fuse should be nearly the same height as the Weidmuller connectors that are mounted next to each one. When not fully inserted these to become intermittent, resetting the radio and/or the RoboRio.

As always, ask your LRI if you have any questions. Do not assume you know the answer. Good Luck everyone.

Al, you should have waited until after the update. The firmware requirement for the roboRIO was removed. The image must still be v23.

[Al Skierkiewicz]

Alex,
You are correct, the email telling me that a new inspection checklist was being published came while I was writing the above entry. The difference is the firmware version for the RoboRio. We have been informed by NI that all RoboRios shipped with one of the only two available firmware versions both of which are legal. It is suggested that if you have not updated your RoboRio, do not attempt to install a later version. The installed version will be legal.

[Al Skierkiewicz]

OK, This is going to be a short list for now as I respond to a post elsewhere and some of the reports coming in from regionals this weekend. I know I have said this before but please make sure everyone you know sees this.

Materials that are not safe or cannot be used on FRC robots.
1. Uncoated lead used for ballast. Even if your build location allows lead in it's raw form, if you plan on traveling, the lead needs to be sealed. You can paint it, dip it in tool handle coatings, you can even injection mold plastic around it. Many locations and venues list it as hazardous in it's raw form. If you are using sealed lead, it may not be machined, drilled, cut, etc. while at an event.
2. Mercury in any form. It is hazardous in this country and many other countries. Just shipping it requires specific methods and documentation. Small quantities may be handled differently depending on locale. R8 specifically disallows any switches or contacts that use mercury. If a team happens to spill mercury onto the field, it becomes a hazardous materials site.
3. Any ballast attached using duct tape, ty-wraps, or adhesives. Please think about what you are doing. If the ballast comes loose, your robot, other robots and people near your robot will receive the consequence of your actions. Ballast must be attached with known good fasteners, to the frame of your robot. Use of 1/4" hardware or larger, through the ballast and into the frame, is ideal. In some cases, stainless steel hose clamps may be sufficient but it is up to the LRI at your event to make that call. If the Head Ref or FTA see an issue, they may alert the LRI to check your installation again.
4. Anything that can spill onto the field is also not allowed. This means sand, ball bearings, shot, pebbles, or water or anything else that you can think of.

[IndySam]

Al are you saying a small dumbbell weight (2-5lbs) attached to the frame of a robot with zip ties is some kind of a hazard and would not be allowed?

[Alan Anderson]

Originally Posted by IndySam

Al are you saying a small dumbbell weight (2-5lbs) attached to the frame of a robot with zip ties is some kind of a hazard and would not be allowed?

He has said before that zip ties are not a structural fastener. That's what I told the team in Kokomo using them to hold on their hand-weight ballast. One student suggested that they could attach the weights with duct tape instead...

I did a quick tug test and didn't think they were a problem in that case, so I didn't ask an inspector to review it. In a more collision-prone game, I definitely would have done so.

[Thad House]

I get the zip tie thing, but at the same time I don't. The field is held together with zip ties and Velcro, and it seems to work just fine. As long as you buy good quality zipties, they could easily hold a robot together.

[Alan Anderson]

Originally Posted by Thad House

The field is held together with zip ties and Velcro, and it seems to work just fine.

Velcro holds the field to the carpet, and there's quite a lot of square yards of the stuff doing it. Good luck getting that much holding area on a robot.

Zip ties on the field are used for wire management, not structure. Unless you're talking about the lexan side panels on the original field design, in which case you might be interested to find out that several of them do break on average every event, and they have been replaced with rivets in the new design.

[Jon Stratis]

Originally Posted by Thad House

I get the zip tie thing, but at the same time I don't. The field is held together with zip ties and Velcro, and it seems to work just fine. As long as you buy good quality zipties, they could easily hold a robot together.

The only parts being held together on the field by zip ties are the Lexan covers (NOT structural, these are intended for shielding and to provide a smooth playing surface). In those cases, the physics are well understood - most of the force against those covers will come from head-on collisions with robots, in which case they are pushed against the pipes supporting them. Sliding force has been known to break zip ties on the field, and they are replaced as needed. Additionally, if those zip ties break and the Lexan comes lose, it's not exactly moving - it just flops to the ground. The structural elements to the field (all the aluminum piping) is held together by slotting pieces inside of each other and locking them in place with pins. There is a firm mechanical joint between every part of the field structure, and it's designed so it can only come apart in a very specific way.

Contrast that to a weight attached to a robot. The weight is constantly experiencing acceleration and deceleration as the robot moves around. It can take an impact from another robot, in which case this is two robots hitting each other, not one robot hitting a stationary target. If the robot is spinning in a circle full speed when the zip tie lets go, the weight isn't just going to fall to the floor - it's going to be thrown across the field (and possibly outside of it). This is a much more dangerous situation.

[IKE]

Originally Posted by Thad House

I get the zip tie thing, but at the same time I don't. The field is held together with zip ties and Velcro, and it seems to work just fine. As long as you buy good quality zipties, they could easily hold a robot together.

Emphasis was mine. Often when writing a rules for any sort of sanctioning, the ruless have to written in such a way that if to prevent something dangerous from happening, it is inspectable. For example, in amatuer racing, roll cages are often specified at Steel, of a particular diameter and wall thickness with an inspection hole. While not all steel is created equal, the lowest common denominator is used and specified to ensure that at a minimum the cage should be safe.

As most of us know, Zip-ties vary in quality and strength by a very large range. Do I think you can find Zip-ties that could handle impact loading... Yes. Do I think I can tell the difference between those and "junk ones"... NO (or at least not easily).
A simple McMaster Carr search shows 15 varieties of cable ties with a wide range of ratings. It is also worth noting that with plastics, just because it was originally rated at 100 lbs strength does not mean it will always be that strong. Some plastics degrade with humidity. Other plastic degrade with UV light exposure.
At the end of the day, there is just too high of variation which is why you get the pushback.

Does this mean you will never see a robot with a dumbell ziptied to the back? Doubtfull. It does mean though that once it gets noticed, it will likely be asked to be correctly anchored.

I would still be very impressed if a team showed me the calculations for the resultant G loading of a 10 feet per second robot hitting the wall, the documents that show the cable tie rating, and the calculations and safety factors that make them believe it is OK.*

*for a 10 FPS robot with bumpers that compress 2" ideally it is around 10G. If you assume about 0.25" of deflection it is nearly 100G. Thus a 10 lb dumbell might exert 100 to 1,000 lbs. of force on those restraints.