Disabled robots moving

[ollien]

I recognize this is probably a stupid question, but I'm going to ask it anyway. I was contemplating this on my ride home today. At NYC, an inspector told me about a robot that was DQd because they ran their fan after they were disabled. This got me thinking. Though the RoboRIO and legal motor controllers will not function when the robot is in a DISABLED state, provided no other control system rules were violated, is it technically legal, regardless of if it's physically possible, to have an actuator move while the robot is DISABLED? I can't find a rule explicitly stating this one way or the other. The best I can find is the definition of DISABLED: "a state in which a ROBOT has been commanded by the Driver Station to deactivate all outputs." Perhaps this would be in violation of G1?

[NWChen]

I think G1 explicitly applies here:

...Uncontrolled motion that cannot be stopped by the DRIVE TEAM.

A disabled robot cannot be controlled by the drive team, in which case the continued motion of an actuator is uncontrollable and thus unsafe and illegal.

Originally Posted by ollien

I was contemplating this on my ride home today. At NYC, an inspector told me about a robot that was DQd because they ran their fan after they were disabled.

This seems counterintuitive to me. A fan should run while a robot is disabled (but still powered on); for it not to run, e.g. in the case of control by a power-regulating device like a motor controller, would have it turn on/off based on the output of said motor controller. That runs contrary to both R52 and general sense.

[Christopher149]

Fans (at least those that are small and cooling motor controllers and motor) are allowed to run all the time by R52 - we've done it this way for literally forever. About all I can imagine is that this was a large motor-powered fan for deflecting boulders, or a miscommunication.

[ollien]

I didn't see the robot personally, but if I remember our conversation correctly, the fan was wired directly to the robot battery.

Thank you all for answering the original question however! I know it's kind of a nitpick, but I do appreciate it.

[NWChen]

Originally Posted by ollien

I didn't see the robot personally, but if I remember our conversation correctly, the fan was wired directly to the robot battery.

Thanks for the clarification, the robot inspector's decision makes sense then by R48. I do recall a case of one robot at NYNY having an improperly connected fan that needed to be rewired to the PDP.

[cbale2000]

Originally Posted by ollien

I was contemplating this on my ride home today. At NYC, an inspector told me about a robot that was DQd because they ran their fan after they were disabled. This got me thinking. Though the RoboRIO and legal motor controllers will not function when the robot is in a DISABLED state, provided no other control system rules were violated, is it technically legal, regardless of if it's physically possible, to have an actuator move while the robot is DISABLED? I can't find a rule explicitly stating this one way or the other. The best I can find is the definition of DISABLED: "a state in which a ROBOT has been commanded by the Driver Station to deactivate all outputs." Perhaps this would be in violation of G1?

My understanding of the rules is that fans are not required to be connected to motor controllers, as a result, cannot be expected to turn off when disabled. For that matter, motor controllers that use fans are specifically wired so they always run, effectively making Victors and Jaguar motor controllers illegal if the rule was to be interpenetrated this way.

This looks like an obvious case of a ref that needed to seek clarification on the rule. This is the kind of thing that should only require a little common sense, but it seems like more and more this stuff needs to be spelled out for people to avoid lawyering.

[ctt956]

Originally Posted by cbale2000

My understanding of the rules is that fans are not required to be connected to motor controllers, as a result, cannot be expected to turn off when disabled. For that matter, motor controllers that use fans are specifically wired so they always run, effectively making Victors and Jaguar motor controllers illegal if the rule was to be interpenetrated this way.

This looks like an obvious case of a ref that needed to seek clarification on the rule. This is the kind of thing that should only require a little common sense, but it seems like more and more this stuff needs to be spelled out for people to avoid lawyering.

I'd think that if the fan is built in to a motor controller, it's legal as that's part of the controller. As with the practice robot I mentioned above, fans installed that weren't built in should only be a problem if they're unsafe(blades completely exposed).

[cbale2000]

Originally Posted by ctt956

I'd think that if the fan is built in to a motor controller, it's legal as that's part of the controller. As with the practice robot I mentioned above, fans installed that weren't built in should only be a problem if they're unsafe(blades completely exposed).

Right but if the refs translation of the rule is "it cannot have any parts that keep moving even when disabled" then they wouldn't be legal under that interpretation.
I was merely giving an example of how insane that interpretation is because it totally goes against other rules, the intent of the rules, and basic common sense. Now, as mentioned by ollien, this appears to have not been the reason in this case but as OP presented it, it would have been a horrible ruling.

[ollien]

Originally Posted by cbale2000

Now, as mentioned by ollien, this appears to have not been the reason in this case but as OP presented it, it would have been a horrible ruling.

Yeah, I should have been more clear. I was more stating it to give context to my thoughts instead of making it seem like I was some kind of nefarious robo-villain.

[FrankJ]

This is where you graciously ask for the LRI. KOP fans do not require a motor controller so they will run when the robot is powered on. R52. When someone says "it is against the rules" they need to be able to say specifically which rule it is against.

[ctt956]

Originally Posted by ollien

I was contemplating this on my ride home today. At NYC, an inspector told me about a robot that was DQd because they ran their fan after they were disabled. This got me thinking. Though the RoboRIO and legal motor controllers will not function when the robot is in a DISABLED state, provided no other control system rules were violated, is it technically legal, regardless of if it's physically possible, to have an actuator move while the robot is DISABLED? I can't find a rule explicitly stating this one way or the other. The best I can find is the definition of DISABLED: "a state in which a ROBOT has been commanded by the Driver Station to deactivate all outputs." Perhaps this would be in violation of G1?

A fan, as in a cooling fan? Yes, it's possible for those to run when the 'bot is disabled. I've seen Talon fans wired to the Talons' power inputs run while the robot was disabled(this was a practice robot, not competition). As for legality, I'm not sure. I know the head ref makes the decision, but I would say that a team should not be disqualified over a spinning fan unless it poses a fairly significant safety hazard. A warning might be in order, though, since nothing should be moving when disabled. The maybe disqualification if they refuse to fix it(or at least acknowledge it if they can't easily fix it).

[GeeTwo]

This doesn't follow from the robot rules as I read them.

Emphasis mine:

Originally Posted by R52

With the exception of servos, fans, or hard drive motors permitted in R29, each actuator must be controlled by a power regulating device.

Originally Posted by R66 C

Fans may be attached to motor controllers and may be powered from the power input terminals.

The only other mention of fans in the rules is a limit of a 20A breaker (R48, third row of table), the description of allowed fans (R29, last row: from a KoP, or part of COTS devices).

I can find no rule that requires that a fan ever be switched off apart from a main breaker disable; the rules appear to allow it to be run directly from the output of a PDP breaker, though not quite explicitly.

G1 (generic unsafe operation) is a possibility, but this should have been accompanied with a statement as to why it was unsafe/what had to be corrected. (e.g. a large unshrouded fan is an obvious safety hazard, even if it's behind a motor controller).

Edit: No, it may not be wired directly to the battery; you do have to go through a 20A or smaller breaker per R48.