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Unread 09-03-2015, 18:48
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Re: Al's Annual Inspection Thread 2015

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Originally Posted by GaryVoshol View Post
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!"
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Unread 09-03-2015, 18:56
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Re: Al's Annual Inspection Thread 2015

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.
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Unread 09-03-2015, 19:21
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Re: Al's Annual Inspection Thread 2015

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Originally Posted by AdamHeard View Post
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.
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Unread 09-03-2015, 20:31
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Re: Al's Annual Inspection Thread 2015

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Originally Posted by GaryVoshol View Post
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.
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Unread 10-03-2015, 14:40
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Re: Al's Annual Inspection Thread 2015

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.
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Unread 10-03-2015, 16:55
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Re: Al's Annual Inspection Thread 2015

Quote:
Originally Posted by Al Skierkiewicz View Post
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.
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Unread 11-03-2015, 08:31
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Re: Al's Annual Inspection Thread 2015

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.
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Unread 15-03-2015, 10:39
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Re: Al's Annual Inspection Thread 2015

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.
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Unread 15-03-2015, 10:48
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Re: Al's Annual Inspection Thread 2015

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?
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Unread 15-03-2015, 13:00
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Re: Al's Annual Inspection Thread 2015

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Originally Posted by IndySam View Post
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.
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Unread 15-03-2015, 13:10
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Re: Al's Annual Inspection Thread 2015

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.
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Unread 15-03-2015, 13:54
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Re: Al's Annual Inspection Thread 2015

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Originally Posted by Thad House View Post
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.
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Unread 15-03-2015, 14:04
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Re: Al's Annual Inspection Thread 2015

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Originally Posted by Thad House View Post
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.
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Unread 15-03-2015, 15:12
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Re: Al's Annual Inspection Thread 2015

Scott,
Yes.
Anyone who does not think high speed collisions are not possible should have been at a friendly scrimmage/practice I attended yesterday. One of the robots had a "software" glitch and drove across the field at full speed into the player station.
Thad, I can assure you that zip ties are not rated for dynamic loads and are known to fracture under a variety of conditions, most of which are present during FRC matches. If you watch the field as closely as some of us, you will have noticed the FTA or FTAA running back to the field box and pulling out ties to replace those broken by robots every day, every event.
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Unread 16-03-2015, 02:15
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Re: Al's Annual Inspection Thread 2015

Quote:
Originally Posted by Alan Anderson View Post
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.
In last year's field zip ties and gravity were the only things holding the high goal and its support structure above the heads of the drive team. This year the tote chute's ramp and cover are held together by zip ties and gravity. From my understanding the original AndyMark fields did ocassionally break the rivets that held the polycarb panels which are a structural element in the AM field. I believe that they uprated the rivets used in the production versions because of this.

Quote:
Originally Posted by Jon Stratis View Post
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.
There are zero pins holding the traditional field together this season. Last season there were a hand full of pins used to keep the high goal together but not to keep it supported above the driver's head. The shelf that the high goal structure sat on was attached to the driver's station uprights by zip ties. Yes the shelf had semi circle notches that kept them centered on the upright and served to transfer the load, however without the zip tie it would have been very possible to bump it in a manner that could send the entire structure crashing down. Yes those zip ties were heavy duty, rated for 150lb load IIRC and there were several, but still zip ties were an integral structural element in last year's design. With the impacts the driver's station wall saw last season I was always a little afraid of what could happen during one of those sever impacts. It was normal for the field to grow a couple of inches over the course of an event due to those impacts. I saw many cases where a substantial lump formed in the carpet behind the driver's station due to the impacts stretching the carpet.

I do not know for certain if there are any pins in the AndyMark field because I have only seen the flyer and not seen one in the flesh.
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