Hello again
I am from team 3218 and I had a question about batteries on the robot.
Are we allowed to put an extra battery on the bot if it is only being used as a counter balance to counter the weight from the battery being used for power? the battery would not be connected to anything and would not be any extra power
Thank You
I would not use a battery as a counter-weight. Find some chunks of steel and use those instead.
I cannot quote a specific rule from the manual saying you can’t but I would advise against it. With the leads of the battery or the anderson connector not connected to anything, it would create a potential safety hazard.
I concur with the above Wiifi’s opinion on the safety rules. I do not think that it would be safe, as exposed wires could short. You could also damage the battery!
Using a giant brick of steel (or some other material) would be safer and better.
I did some quick calculations and a battery-sized piece of steel would weigh about 40lbs, which is heavier than the battery iirc. This means you could use a smaller piece of steel, or have a heavier (and possibly more effective) counterweight.
I agree with everything that was already stated.
I suggest that you go to Goodwill or some other thrift shop and buy some free weights. They always seem to have a few random pieces around. Used sporting good shops also sometimes sell extra unmatched weights individually for a modest price.
The advantage of using weight lifting weights is that if you buy them in small weight units the weight will be easily adjustable. They are also more compact, and they come with a convenient mounting hole.
There’s a picture floating around here of a robot with free weights attached to it. I can’t remember the competition or the year but I remember seeing it…
I remember seeing a robot with an arbor press attached to it as ballast…
I think that may have been my doing… >.>
I was on MOEbile pit and the team’s robot was so light their wheels has almost no traction. I used their pit vice as the clamp to attach the press to the frame for even more weight 
Aj,
One and only one battery is permitted on the robot, see R34. Other battery types are allowed if and only if they are part of a COTS computing device or enclosed camera. Weight may be added provided a few items are met.
Free weights, steel plate, vises, etc. must be firmly attached to the robot. Ty-wraps, tape, wire, twine or rope, etc. do not meet the “firmly attached” definition. Attachments can be appropriate hardware, welding, etc.
As to lead, it must be entirely painted or sealed prior to attending an event. It may not be machined at the event.
As to other types of weight, notably shot, sand, liquid, etc., this must be enclosed in a container that will not spill or crack open with the forces normally encountered on the field. More than once, teams have added these items and we spent considerable time cleaning the residue from the field.
Considering the nature of the game, if you climb, it seems that additional weight would work against you.
R34 actually says:
The only legal source of electrical energy for the ROBOT during the competition, the ROBOT battery, is one of the
following 12VDC non-spillable lead acid batteries:…
I’m not saying that using a battery as ballast is a great idea, but is it automatically ruled out by R34? If the ballast battery has nothing connected to its leads, then it’s not a source of electrical energy for the ROBOT.
Of course, there are safety issues to be addressed, and I think there are better ways of adding ballast to a robot. But, I can’t resist a good debate.
I’m just saying I don’t think the battery as ballast is inherently illegal.
That is why I didn’t quote R34, it is debatable if the battery is not being used as an energy source. I think for safety’s sake it should not be legal, and if you were to ask it on Q & A they would probably rule against you using it as a counter-weight.
Cal,
Please note that all references to the battery in the robot rules is in the singular, meaning one. This has been answered in the Q&A for several years in this fashion. However, I do not remember seeing that question asked this year. If there is still some confusion, someone should ask to remove all doubt.
I would say that having an extra part of acid and lead is by definition unsafe. One is dangerous enough.