I agree with Stu on the cost/effort part, although the current performance
of my speedometer means I will have to do SOMEthing in the future... The
problems with doing an electronic speedo/odometer are (a) the part where the
mechanicals meet the electronics and vice versa (gotta drive that odometer
somehow, in an accurate way), and (b) making the electronics bulletproof
enough to survive years of heat, moisture, vibration, and electrical
glitches. In my recent tach guts redesign (still haven't tested it... maybe
this weekend) about half the parts were there just for voltage regulation
and protection from spikes.
Hmmm... use a Hall sensor pickup on the wheel studs... programmable counter
to drive a solenoid to advance the odometer... a tach meter movement for the
speedo... yeah, that's it... some Tardis paint to make it all fit inside the
case...
Theo
-----Original Message-----
From: stuart_brennan@agilent.com [mailto:stuart_brennan@agilent.com]
Sent: Wednesday, October 18, 2000 8:33 AM
To: Tigers@autox.team.net
Subject: Electronic Speedometer?
Yeah, an optical pickup off the driveshaft would work great. UNTIL that
rally you are on goes up a dirt road and some mud splashes up on the
lens....... Magnetic might be better. Better yet, use the standard
Speedometer cable location to mount an encoder of some type, then go to
electronics.
I may be an EE, but don't count me in on any design efforts. Why make
something more complicated than necessary? The stock setup, with a
different tooth count or a custom recalibration of the Speedometer, will do
just fine. Probably cost less in cash and effort than messing around with
your own electronic design, too.
Stu
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