What triggers a re-inspection? Really.

FIRST General Forum
1

**TL/DR:**Old guy tells a story then asks “How much change do you have to make to a robot before you need to get it reinspected?”

Hey CD,
I was helping a team get their climber working at NE RIDE (awesome fun competition – really enjoyed being involved).

Anyway, after the draft but before the playoffs, the Bat Signal went up in the pits for a “64:1 gearbox” Really? a 64:1 gearbox - that’s it? Seems like there had to be something more specific they needed than just any 64:1 gearbox some team happened to pack from the gearbox boneyard*. I had to go check that out.

Turns out the team had a CIM + Banebot 64:1 gearbox (BB220???) and a roughly 4" winch drum. Solid enough solution I would think. Should lift 150lbs at about 1 ft/sec drawing about 30A. Not bad. But it was broken, they didn’t have a spare and they needed a work around.

Team 88 just happened to have a VersaPlanetary stash, an extra 775Pro, and a VersaFrame Gusset for a VersaPlanetary** laying around in our pit***.

So I set to work to build up a 250:1 VP with a 775Pro input and an output with their required 1/2 round shaft with keyway****. Should give them very similar performance in terms of climb rate and currents.

We were almost done when the robot had to be carted off to the inspection station to get reweighed and reinspected. I don’t think this was the “every robot that competes in the playoffs” gig. I think this was because they thought that the change required it.

It wasn’t the ONLY reason they didn’t get their climber working before they were eliminated but it definitely was a big part of it.

I am not going to advocate breaking rules or anything but it didn’t seem to me that this was a very significant change. They replaced one legal motor/gearbox for another legal motor/gearbox that essentially duplicated the one they were replacing. If anything the weight dropped by a few pounds.

I would have probably said they’d be okay to just hop in the robot queue and compete.

Would I have been wrong?

What does the CD community think?

Do tell.

Dr. Joe J.

*Any team with more than 4 seasons behind them has such a boneyard: No real use for this gearbox anymore, but it’s too good to toss. What are you going to do with it? Put it in that pile there.

**I swear, I am not on the payroll of the Vex folks. I just like many of their products. I’m just as happy to say good things about BB or AM or WCP or JoeBlow’s FIRST Gadgets as long as they make useful stuff for FIRST teams to more easily realize their robotic aspirations.

***in case we ever get a hankering for some tasty cheesecake. You know what I’m talking about…

****Really folks, use hex shaft if you are transferring torque with a shaft in FIRST applications – Trust me on this. Yes, you can make keyways and keys work but hex is your friend. You’ve got a lot to worry about on a FIRST team. Transferring torque via shafts shouldn’t be one of them. Use hex shaft whenever you can. And buy the AM broach. Worth it.

2

I was inspecting this past weekend and whenever a team came to me after they’d already been inspected telling me that they’d made a minor change (in most cases teams just added a small piece of poly somewhere) I just took a quick look, told them it looked good, but I still had them go re-weigh. Not because I thought the weight would have changed significantly, but I’m just trying to save teams and inspectors from panicking if a team weighs in for elims and the number is off from what is was for quals because the team didn’t re-weigh after the small change. If teams told me this on practice day, I just told them to continue playing practice matches if they wanted to practice and get re-weighed after the field was closed.

3

I mean, yeah, they SHOULD get reinspected, but from my inspection experience, when teams had to get reweighed after their last match we would ask them what was modified if there was any weight discrepancy. So teams obviously make changes without getting reinspected, so even if you get reinspected after the match just played (especially in a hurry), you’ve gotten reinspected more times than most (most teams won’t bother to get reinspected after modifications, but some do).

4

I would say that I05 does in fact require reinspection of the robot in this case. The key word is “identical” in parts D and E of said I05. Changing a BB gearbox for a Versa and a CIM for a 775Pro is definitely not identical. It’s a different COTS gearbox and a different motor, therefore, it needs reinspection.

That being said, it should be a “is this still legal”-grade inspection: Robot on scale, check volume if it’s close to the outside, verify wiring for that motor only, ask about the cost (maybe), “go win this one”. Any reasonable inspector should be able to turn that around in about 3 minutes once the robot arrives at the scale.

5

The official answer is:

I05. Unless the change is listed below, any change to a ROBOT must get re-inspected. If a ROBOT is modified after it has passed its most recent Inspection, that ROBOT must be reInspected before the ROBOT is eligible to participate in a MATCH. Exceptions are listed in A through F (unless they result in a significant change to the ROBOT’S size, weight, legality, or safety).
A. addition, relocation, or removal of fasteners (e.g. cable ties, tape, and rivets)
B. addition, relocation, or removal of labeling or marking
C. revision of ROBOT code
D. replacement of a COTS COMPONENT with an identical COTS COMPONENT
E. replacement of a MECHANISM with an identical MECHANISM (size, weight,
material)
F. additions, removals, or reconfiguration of ROBOT with a subset of MECHANISMS already inspected per I02.

So changing to a different motor and a different gearbox does require a reinspection. In the case where you’re going to be close on time before your next match, get an inspector involved early! Send someone to bring him to your pit. Explain what you’re doing. Ask him to work with you as you finish the change in order to expedite the process. In such a situation, as an LRI I would pull the inspection form and say “They’re XXX lbs, it doesn’t sound like there’s any chance they are going to be overweight. Go help them, make sure everything is safe and legal. If we need to, we can worry about reweighing the robot after their match.” Of course, if the team doesn’t get us involved early, then it takes more time as we need to actually look at the change before waving them on to their match. If teams work with us, we’ll do everything we can (within the rules) to get them on the field for their match, working as fully as possible.

6

I05. Unless the change is listed below, any change to a ROBOT must get re-inspected. If a
ROBOT is modified after it has passed its most recent Inspection, that ROBOT must be reInspected
before the ROBOT is eligible to participate in a MATCH. Exceptions are listed in A through F (unless they result in a significant change to the ROBOT’S size, weight, legality, or
safety).
A. addition, relocation, or removal of fasteners (e.g. cable ties, tape, and rivets)
B. addition, relocation, or removal of labeling or marking
C. revision of ROBOT code
D. replacement of a COTS COMPONENT with an identical COTS COMPONENT
E. replacement of a MECHANISM with an identical MECHANISM (size, weight,
material)
F. additions, removals, or reconfiguration of ROBOT with a subset of MECHANISMS
already inspected per I02.

It doesn’t sound like it was a replacement of an IDENTICAL COTS COMPONENT or MECHANISM so it should be reinspected.

7

Jon and I must have been typing at the same time…

8

As much as I’m not an RI, there’s still a lot to go wrong with a brand new motor that I can point out. For example, if the said motor was taken from a corner of the pit scrap pile as you say, it could have an electrical issue causing it to short to the frame. We actually spent about two hours on Thursday of our competition debugging a short issue until we found one of our sensors we put on after the start of the day. Also the re-inspection of all the connectors being properly insulated and properly gauged is important. Meanwhile, if you’re like our team who actually had to take stuff off after inspection (a gear got stuck in our fuel storage), i don’t think that’s warranting for a brand new inspection. Either way, most changes still should only have a quick glance over the affected areas and a new weight just for the sanity of everyone involved.

9

Absolutely reinspect. Different type of gearbox, different “winch drum”, different motor.

Consider also if it had been the other way, and the 775 pro were swapped out for a seventh CIM.

10

Removing stuff can cause just as many issues as adding stuff. For example, removing a motor could leave exposed wires that could short to the frame. Removing structural members could leave your bumpers improperly supported. Removing gears, chains, or sprockets could result in a part hanging outside your FRAME PERIMETER or digging into and damaging the carpet. So yes, we do still need to look at the change :slight_smile:

11

With a different gearbox and a different motor, that would definitely seem to require reinspection.

With that said, at any event I’ve inspected or competed at, the inspectors would work with teams that knew they were going to need reinspection on a tight timeframe. In a case like this, the reinspection would really only be checking on the changes, and weighing the robot. Weighing might even be left until after a match if time was tight, as long as the robot was far enough under max weight. As mentioned above, if the inspectors knew in advance, they’d be hanging out nearby ready to reinspect and get the team out ASAP.

12

In this case it was a few simple brackets in the complete interior or the robot that had absolutely no electrical nor moving components on them except a small servo which we removed all the wiring for. None of us saw any rule that this could impact, but in hind sight, I should have gone and grabbed one of the inspectors. Being a walking, talking manual makes me a little cocky about some of these things sometimes.

13

Personally I’m fine with any change needs reinspected, as long as reinspection is right-sized for the change.

Add something internal/structural to the robot but the perimeter or volume hasn’t changed? Check for sharp edges and re-weigh.
Modify part of the electrical circuit? Check the new wiring and re-weigh.
Cheesecaked a mechanism? Thoroughly inspect the new mechanism and re-weigh.
Completely build a new entire robot from scratch? Re-Inspect everything.

Re-inspection keeps the competition fair.

14

While I agree that’s a good idea, it’s inconsistent with the rules (emphasis mine):

15

Absolutely they need to get reinspected for that change. The current rules say that you need to get reinspected unless the changes follow a very specific set of changes. We often get reinspected 6-10 times an event because we often drill a new hole before a match and the rules don’t allow that change. I’ve advocated for changing that rule but haven’t been successful and until that happens we will continue to get reinspected multiple times during every event. Most of the time we get reinspected before every match, it’s the exception to the rule that when we don’t get reinspected before a match.

It helps if you get to know your inspectors and tell them that you will be coming by often for them to look at your changes. Know your previous weights and what you changed, if you aren’t close to weight and what you added is clearly/modified is clearly small you often won’t have to be reweighed if you are running short on time.

16

I think our team removed some vision equipment that weighed only a pound or so from our robot back when I was driving. We never re-inspected the robot until after qualifications. When we got to the weigh-in, they simply asked why the robot was lighter and we told them and they just didn’t think anything of it. We’ve also broken pieces of our robot and replaced them before and I don’t recall getting re-inspected because it was an exact replica of what had already been inspected.

So, unless you’re team is straight adding something to the robot or removing a good chunk of it, you’re probably fine to go without re-inspection. I would say that most inspectors aren’t going to care about general maintenance and replacing parts. However, if you’re unsure, you should just ask. Then you don’t really have to worry about it.

17

Rules are there for a reason, everyone is expected to abide by them. We may not agree with every rule, but competition venues are not the right place of discussion or taking short cuts. As others have listed appropriate rules and discussed, everyone must know them and follow. Students learn a great deal from mentors, teaching them to follow rules is one most important thing you can teach. Volunteer inspectors are instructed to weigh robots after last qualification match and if the robot weight is different than the last checked weight they freak out and they have good reason to freak out. Not knowing what has changed and if that change could have given advantage/disadvantage to team or the worse, it was the reason for some accident.

18

Of course the MAIN reason for getting reinspected is because you’re a nice person and don’t want to saddle the LRI and FTA at Saturday lunch with the question of what to do with a robot that’s been competing illegally for the last 6 matches because they didn’t get reinspected.

19

It’s subtle, but I think there’s a difference in the rules between removable mechanisms that you may put on and take off repeatedly over the course of an event and removing something from the robot permanently.

A mechanism that is identified as removable can easily and quickly be inspected to ensure that removing it leaves the robot in a safe state. One that isn’t designed to be removable probably falls under the " (unless they result in a significant change to the ROBOT’S size, weight, legality, or safety)" clause in I05.

20

Your own integrity, plain and simple.

If you believe that you are making a simple change that will not affect checklist that was ran through during inspection, then all should be fine. However, any major changes that may not affect the inspect checklist but do change the functionality of your robot should then be brought to their attention.

I always play it on the safe side and bring the bot to the inspection crew regardless of the situation.