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<DIV><SPAN class=370124516-20092004>Hi John</SPAN></DIV>
<DIV>No fuzzy logic! When the stick moves. something deterministic should
happen!</DIV>
<DIV><SPAN class=370124516-20092004>I suspect that the existing ESC makers
already have all the hardware needed, as brushless brakes only require an
intentionally retarded commutation timing, while brushed motors require the
additional shorting transistors. But you can never have enough projects going at
once ... eh?</SPAN></DIV>
<DIV><SPAN class=370124516-20092004>We'll t</SPAN>alk later,</DIV>
<DIV>Dean</DIV></DIV></DIV>
<DIV> </DIV>
<P><FONT face="Times New Roman">Dean Pappas</FONT> <BR><FONT
face="Times New Roman">Sr. Design Engineer</FONT> <BR><FONT
face="Times New Roman">Kodeos Communications</FONT> <BR><FONT
face="Times New Roman">111 Corporate Blvd.</FONT> <BR><FONT
face="Times New Roman">South Plainfield, N.J. 07080</FONT> <BR><FONT
face="Times New Roman">(908) 222-7817 phone</FONT> <BR><FONT
face="Times New Roman">(908) 222-2392 fax</FONT> <BR><FONT
face="Times New Roman">d.pappas@kodeos.com</FONT> </P>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> discussion-request@nsrca.org
[mailto:discussion-request@nsrca.org]<B>On Behalf Of </B>John
Pavlick<BR><B>Sent:</B> Friday, September 17, 2004 9:19 PM<BR><B>To:</B>
discussion@nsrca.org<BR><B>Subject:</B> RE: Motor Costs Comparison (more
pro-electric)<BR><BR></FONT></DIV>
<DIV><SPAN class=400170301-18092004>Dean & Matt,</SPAN></DIV>
<DIV><SPAN class=400170301-18092004> Yes. I forgot to mention the the
"programmability" factor of an electric motor. Whereas a glow motor's
characteristics come from mechanical things (bore, stroke, port timing, etc.),
an electric motor and speed controller can work together to alter the torque
curve. Some speed controls take advantage of this now, but most people
don't realize it. The better speed controls use a non linear type of output
(I'm oversimplifying here) to make the electric motor "feel" more like a glow
motor. I haven't worked much with the brushless motors but I have a bit of
experience with the can motors (from R/C car racing). It seems like what we
need is a speed controller with a P.I.D. control loop. The currently available
ones are one dimensional / open loop. The throttle stick simply increases or
decreases the output of the motor. The speed controller just changes the PWM
duty cycle in direct response to the stick position. We need some feedback and
Fuzzy Logic to do this right. Dean: If you design the hardware, I'll work on
the code...</SPAN></DIV>
<DIV><SPAN class=400170301-18092004>
<P><FONT size=2>John
Pavlick<BR></FONT></P></SPAN></DIV></BLOCKQUOTE></BODY></HTML>