17-01-2007 00:36

Gabe

Re: pic: mounted Anderson

You sure its okay with FIRST that you screw things into the battery plastic?
I love the way it just clicks in, but I would have used epoxy or some other kind of adhesive instead.
(It seems screwed to the battery to me.)

17-01-2007 00:54

Tristan Lall

Re: pic: mounted Anderson

If that's attached to the battery, it's illegal per <R65>.

Is the battery held in only by the Anderson connector? That wouldn't be sufficient—that battery desperately needs to be secured, to avoid it coming loose. (Consider what would happen if your robot were flipped.) Also, it might not be a great idea to put such sharp bends in the 6 AWG wire at the base of the Anderson connector (that will just increase the resistance and cause it to heat up, wasting energy in the process).

17-01-2007 01:09

Elgin Clock

Re: pic: mounted Anderson

The Good:
The Anderson quick disconnect was not tampered with in any way possible.
The quick disconnect housing has 2 holes in the center of it already.

Since they did not drill, machine, or otherwise into that part, it would be legal and I've seen this done hundreds of times with many teams before with no problems.

The Bad:
I do agree some more needs to be done to hold the battery down though. Maybe a velcro strap, or something. Anything.

17-01-2007 01:16

Tristan Lall

Re: pic: mounted Anderson

It's not the Anderson connector that I'm concerned about modifying (though that's not necessarily a great idea either). It's the main battery. Those screws look like they're in the top of the battery, probably in the cutouts beside the vent cap cover. If it's just sitting there, and the screw heads are just for decoration, I could see it being legal—but what are the chances of that?

And yes, I do realize that drilling through that thin flange probably won't be a hazard. But the slightly increased possibility of a stress fracture or some other gruesome fate precludes that sort of modification, no matter the location. I don't think FIRST will look fondly upon this modification, but go ahead and ask the Q&A for permission (describing specifically why this is a safe modification in your opinion), because I know you don't want to have to buy new batteries to replace the modified ones.

17-01-2007 07:40

Donut

Re: pic: mounted Anderson

I don't know for certain, but that metal bracket could just be glued on. 842 has attached handles to their batteries for a couple of years now (pretty sure they're glued), and I don't believe they've had problems passing inspection anywhere before.

17-01-2007 09:17

Richard Wallace

Re: pic: mounted Anderson

Inspectors sometimes make mistakes due to oversight or incomplete understanding of the rules. I've done it, and was lucky to have someone around who caught what I missed.

Gluing components to the battery is not allowed per <R65>. Similar rules have disallowed this in previous years also.

17-01-2007 09:59

Tristan Lall

Re: pic: mounted Anderson

In any case, if you look at the other picture that they posted, it's definitely screwed through* the battery.



*Remember the old joke about drilling holes in the battery (to lighten it, back in the days when the battery counted toward the robot's weight)?

17-01-2007 10:24

Elgin Clock

Re: pic: mounted Anderson

Oh.. through the handle.

Meh. I guess it's a good thing I'm not an inspector then, cause I would let that go.

17-01-2007 10:38

Richard Wallace

Re: pic: mounted Anderson

Elgin, I understand your feeling there. The location of those holes in the battery case is not as dangerous as some other possibilities. Sometimes when a rule violation seems unimportant we are tempted to let it pass. However, as Dave pointed out recently, it is not a robot inspector's prerogative to apply the rules selectively. That would be the same as making a new rule, and making rules is the GDC's job.

In this instance, stress transferred to the battery case through the drilled handle (e.g., due to shock loads when the robot hits something, or by installing a new battery in a hurry) may be outside of the limits considered by the battery's manufacturer when they designed the case. So my opinion is that <R65> makes sense as applied to this situation. But really my opinion about the rule doesn't matter; the rule is there and as an inspector I have to note the violation, and require the team to correct it before their robot can pass inspection.

17-01-2007 14:09

Kris Verdeyen

Re: pic: mounted Anderson

Would attaching sticky back velcro to the battery be considered a modification?

17-01-2007 16:33

sanddrag

Re: pic: mounted Anderson

Do we all have small hands or something? I can pick up the battery with no problem just as it comes. If you can't use both hands. If you don't have two hands free, grab a team mate. It is a probably a good idea to assign one person to be in charge of the batteries anyhow.

17-01-2007 20:18

mizscience

Re: pic: mounted Anderson

No, as that is you adding something to secure the battery, not you trying to permanently attach it to the robot or screwing into it or some other such modification.

17-01-2007 22:21

DonRotolo

Re: pic: mounted Anderson

Hey, at least they find out NOW that it's not allowed, rather than at inspection.

Telling them is GP.

Don

19-01-2008 11:49

PDF32100

Re: pic: mounted Anderson

welll i couldnt find a pic of our last year rock and roll robot but we did have the battery right in the front it was protected we had the anderson connector coming aLl the way from the backk to the front and we did screw it onto the frame so it just clicks in as shown we had no problem with it and no problems given from the judges