Subject: Re: Reducing contact resistance for low volt use?
Summary: What do you think of these ping times eh?
Reply-To: You can't see me, and I pass right through planets...
References: <email@example.com> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org>
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Date: Tue, 07 Jan 2003 12:49:11 GMT
NNTP-Posting-Date: Tue, 07 Jan 2003 07:49:11 EST
On Tue, 07 Jan 2003 02:07:59 GMT, jmuchow@SPAMMENOTcamlight.com (John
Muchow) Gave us:
>>>> Hahahah... #2 wire on a "D" cell. How hilarious. Your devices stall
>>>>from the raw weight you put on them.
>The weight of #2 wire is inconsequential in a 250lb, 9HP robot.
>Several builders use even larger gauges to their battery packs (20-30
>cell strings of C cells, typically) and almost all of those
>connections are soldered.
If the weight of it is 250 Lbs. , one can certainly put more
>>>> Again, testing banks is one thing. Single cells, entirely another.
>>>>Testing them to the point where their voltage drops to nil due to
>>>>short circuit loading as opposed to "normal" discharge rates...
>>>>Not needed. If your discharge rates are of such a nature, you are
>>>>stepping outside the specs for the battery's proper use.
>Yes! You finally get it!
>There is NOTHING in a combat robot that is used at the component's
>spec. In fact, a builder who does so has almost no chance of winning
>an event and will challenged by other builders to explain why they are
>wasting their time building such a machine.
The motion control industry does quite well at arriving at point B
from point A from mechanics operating within the spec. I could build
such a machine, beat you, and beat you worse still, were I to *tweak*
mine out the way you describe.
> We don't need thousands
>of hours of life. If the motors, batteries, wires, etc., last a few
>hours, we're happy. If they last 3 minutes during a fight, we're even
With a 250 gross weight, batteries could easily be the winning
factor. Not how well you make a small bank work, but how well you
make the balance between bank size, available space, and electrical
>100A discharge current, though at the high end of the scale, is not
>unheard of. Plotting voltages and time-to-discharge curves for
>discharge currents from 5A to 100A is a great way to see if there are
>any differences between manufacturer's cells (and at waht current
>levels they occur). If not, GREAT, we can purchase the least
>expensive ones. If there is, we need to know.
It could easily vary from battery to battery, and from lot to lot.
It could just as easily appear as if a random batch all behaved
exactly the same.
>>>> Denying that, and moving forward with the improper usage doesn't
>I would *never* use a component in my 'bot at its rating (except for
>radio receiver max Vcc). That's "proper usage" in a combat robot.
So is using the right capacity bank. THEN, you can push *THAT*.
>Improper usage is sticking to the ratings. It's a waste of time and
>money as all the competition will have faster, more powerful, and more
>dangerous 'bots to stomp mine with as I limp around the arena.
I have seen motion control mechanisms push some quite large loads on
transit beds of machinery, pretty damn quickly.
>>>> Like I said, you need MORE batteries in parallel, not series.
>No, I don't.
>If we can run our batteries at high discharge current levels (without
>having to parallel additional strings of cells together), then I have
>more weight for armor, weapons, etc.
Sounds silly. A minute ago, speed was king. Now, speed is
sacrificed for "armor".
The "bullet proof" panels in armored limos are made from aluminum
plates. Quite light in weight, actually. Are some of your bots
toting firearms? If not, how much "armor" could possibly be needed,
when a simple aluminum plate stops bullets in cars, everyday?