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<DIV>I hate to be a party pooper, but a constant speed control loop is not
permitted under the existing FAI Rules as I understand it for our wet engines.
Is it allowable for the dry whiners?</DIV>
<DIV>BTW, I am all for closed loop control devices...</DIV>
<DIV> </DIV>
<DIV>John Ferrell <BR><A
href="http://DixieNC.US">http://DixieNC.US</A><BR></DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=d.pappas@kodeos.com href="mailto:d.pappas@kodeos.com">Dean Pappas</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, September 20, 2004 12:52
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> RE: Motor Costs Comparison (more
pro-electric)</DIV>
<DIV><BR></DIV>
<DIV>
<DIV>
<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>
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<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></BLOCKQUOTE></BODY></HTML>