A picture is worth a thousand.......
Having thought about this some more, Jon, you're right about kid's toys and
what you are brought up on, as I said a few days ago, boats (and for that
matter most aeroplanes) manage by steering from the wrong end.
The problem with rear steer is that it requires anticipation (and a blind
faith in the future) on the part of the driver. Consider a car off the
desired centre line, within the limitations of the character set (you'll
need to select a monospaced font for this like Courier or Lucida):
(For the example we'll assume a simple reverse tricycle for the rear steer,
I can't cope with trying to get offset rears to look right)
You start a fair way offline, and turn towards the line:
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+-------+ | +-------+ |
| / / | | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | \ | |
+-------+ | +-------+ |
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| |
Once heading back towards the line you straighten up
/ | / |
/ / | / / |
/ / / | / / / |
/ / | / / |
/ / | / / |
/ / | / / |
/ / | / / |
/ / / | / / / |
/ / | / |
/ | / |
This is where it gets to be different.
With a front steer you basically get to the line and point the wheels down
it (obviously there's a progression, but you get the idea).
With rear steer, you need to correct BEFORE you are aligned (like turning
the back of a boat in against the dock).
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/ | / |
/ | / / |
/ | / / / /
/ / / /|
/ / / / |
/ / / / |
/ / / / |
/ / /| / - / |
/ / | / |
/ | / |
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(sorry about the "-" for the rear wheel, but there's nothing between that
and "/" in the character set - I'm sure you get the idea)
Once you're back online, everything's hunky dory:
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+-------+ +-------+
| | | | | | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | | | |
+-------+ +-------+
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Except that you have to effectively anticipate the correction to each minor
deviation in the same way. I'm sure you could condition yourself to it,
but at the end of the day is it worth learning a whole new driving style?
It's also worth noting that neither boats or planes are so concerned
about accurately following a line; they concern themselves only with the
next waypoint, so maybe in today's non-SA GPS era the solution is in
driving to a correction indicator rather than what you see out of the
window.
It's all very well my saying all this - the likelihood of ever having to
prove it is zero. Good luck to any of you guys who have the ability,
money and commitment to actually try any of this out.
Jon Hobden
Horley, England
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