zignig Wrote:
-------------------------------------------------------
> Thanks Forrest,
>
> So from your reply I glean Strip Board will not
> take the current (I hate magic smoke

) to drive
> the motors (17 NMEA VEXTA steppers).
>
I was running some motors that were pulling right at 2 amps/phase. I fried a few traces on startups.
>
> I suspect that multicore wire soldered directly
> pin to pin on the power side of the bridge would
> do the job, or even soldering naked wires along
> the lengths of the track would be even better for
> heat sinking.
>
In most cases just filling the trace with solder did the trick. I got to the point of using about #22 single core pin-to-pin to cover the power tracks and ground connections just to be safe.
I don't like magic smoke, either.
One word of caution. Those diodes with the L298N. Make sure you have them hooked up absolutely correctly before you put power to the board. I had some exciting times learning that.

>
> On a side note, some of the Vorroni work that you
> are doing is very cool. I see that you are using a
> finite element approach (mmm more RAM).
>
RAM's cheap on a PC. Any time I can substitute RAM for code complexity, I'll do it.
>
> You may
> want to look at run length encoding the zones in
> both X and Y axes that way you can just deal with
> the edges of the zone.
>
Too complicated. I like code so simple that I can come back to it in a couple of years and understand what I did in no longer than an hour or two.
>
> You also may want to look
> at post-processing your 'abstract art' and relax
> the edges based on an optimization variable
> (curent for example)
>
I solved the current problem by making sure that Tommelise's steppers don't draw more than an amp at 12v and most times don't draw more than half an amp. I respect the L298N, but it's too dangerous to let a bright 12 year old fool with because of the high amperage levels. As a result, I use the much cheaper SN754410 which can handle 1.1 amps/phase max. It's pretty hard to get that one to do magic smoke.

>
> this would have to be done
> away from the pin areas. .....aaanyway , like I
> said, very cool.
>
I'm looking at some post processing and on-the-fly optimization schemes that will cut down the tool path length and preserve traces, as is, that need to stay minimalised, like the ones to the clock crystals and USB connections.
>
> p.s if anyone wants alternate photos of BORIS,
> speak up and I will post more.
>
Yes, I want alternate Boris pics. Post more and ask Adrian to include you on the Builders Blog so that you can post more formally.
Edited 1 time(s). Last edit at 10/21/2008 11:06PM by Forrest Higgs.