Robot Arm C

[bernard]

Robot Arm Wiki
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Past Threads/Forums: 2011 (Trial), 2012, 2013, 2016

[maxxxxx]

How many arms are we allowed to have. I would assume the maximum is two, but I couldn't find it anywhere in the rules.

[windu34]

How many arms are we allowed to have. I would assume the maximum is two, but I couldn't find it anywhere in the rules.

There is no limit

[chaguy2457]

Hey guys, is it possible for one school to have one robot for three teams? Thanks!

[Unome]

Hey guys, is it possible for one school to have one robot for three teams? Thanks!

As in use the same device for multiple teams during a single tournament? Probably not, based on the Building Policy

[laidlawe18]

Hi,

I have motors that are meant for 12 - 18.5 volts. The recommended voltage is 14.8V. If I use a 12V or 9V battery and step it up to 15V say, that would break the 14.4V rule, I assume. Is that correct, or is it just the labeled voltage on the battery. If I use a 14.4V battery, do you think I'll take a significant hit on torque, etc?

[chalker]

Hi,

I have motors that are meant for 12 - 18.5 volts. The recommended voltage is 14.8V. If I use a 12V or 9V battery and step it up to 15V say, that would break the 14.4V rule, I assume. Is that correct, or is it just the labeled voltage on the battery. If I use a 14.4V battery, do you think I'll take a significant hit on torque, etc?

Technically you wouldn't be breaking the 14.4 rule, but some event supervisors might argue otherwise. There is minimal difference in reality between 14.8 and 14.4V for an application like this. You should be fine.

[jander14indoor]

First, usual disclaimer, but I haven't said it yet this year. NOTHING you see on this forum is official!!! Doesn't matter if its Chalker a committee chair, me the National Event Supervisor, or John Doe random person. We can only offer opinions. They are not binding. ONLY the national site can make binding interpretations of the rules.

And in a moment you'll see why.

I disagree with chalker's (yes I know his first name, but custom seems to be to use login names) opinion and advice.
Quoting from the rules: Only commercial batteries, not exceeding 14.4 volts as labeled, may be used to energize each of the Device's electrical circuits. Multiple batteries may be connected in series or parallel as long as the expected voltage output across any two points does not exceed 14.4 volts as calculated using their labeled voltage.

I'm going to focus on the "expected voltage across any two points" wording. If you are using circuitry to step up the voltage you are certainly violating that wording. Its the key words we've used to disallow conversion to 115V AC or stepping down from 115V AC.

While you might not get 'caught', are the consequences worth it? This falls in the same category as making a device that is .1mm too big. What's the benefit vs risk?

So, you can see why I note that NOTHING on this site is official. If you want an official answer, submit a FAQ to the national site, we'll hash out an answer, and give you one that everyone MUST live with.

Thanks

Jeff Anderson
Livonia, MI

[chalker]

Jeff nailed it on the head - my response was a little too short perhaps. Some event supervisors would penalize you for stepping up the voltage to 15V, some wouldn't, and they might each interpret things differently. The bottom line I was trying to emphasize is to just use the 14.4V max battery without stepping it up, that is clearly within the rules. Your motor should operate just fine.

And yes, as usual, this is not the place for official statements.

[GoldenKnightB]

Last year, I saw several teams use “tools”. One example would be putting a “corral” down so the Ping-Pong balls would not roll away. Tools were often left on the playing surface without penalty.

I think that tools are still allowed this year but the new rule 6g(vii) muddies the waters a bit. It reads the run must stop when “Any part detaches from the Device.”

Tools are not parts. That was made clear last year. (If they were parts, then rule 6g(vi) would have applied).

Comments?

I will be submitting this to Nationals for a rule clarification.