I was googling around looking for other items when I decided to do a rear
wheel steering search. Of course, the Thrust Site came up but as I read
about the mini they used to test their concept of rear steer, I though you
all would like to read the article. I copied the info and pasted it here for
those who do not wish to surf... the url is
http://www.thrustssc.com/thrustssc/Driver/Testing_the_Mini.html
the article is by Andy Greene
mayf
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Rear-wheel steering? You must be mad!' This is the reaction that a lot of
people, including several respected academics, have had when they hear about
Thrust SSC's unique steering concept. After all, the most unstable vehicle
known, the shopping trolley, is rear-wheel-steered, so it can't be a good
idea......... can it? (Mayf's note - shopping carts in this country
generally tend to be front steer). It was to counter exactly this criticism
that Glynne Bowsher, the car's designer, built the rear-wheel-steered Mini
to demonstrate that it is a stable vehicle - it's actually easier to drive
accurately in a straight line than a normal road car! But when Thrust SSC
runs on the desert this Summer, it will be running on a low-friction
surface - what will happen to the steering then?
To find out, the SSC team asked the Defence Test and Evaluation Organisation
at Chertsey in Surrey to help. Part of the Defence and Experimental Research
Agency which has already helped the project so much, Chertsey has a huge
range of vehicle test facilities - they test everything from main battle
tanks to McLaren F1 cars on their tracks. They have a large 'slip pan' which
can be covered in water to produce a low-friction surface, which is where
the Mini and I went to try and simulate the sort of handling surface that
the SSC will experience in the desert.
The initial plan was to find out where the limit of rear-wheel steering was,
what happened at the limit and how I could recognise and control rear-wheel
skids. There was only one problem - I couldn't make the rear wheels skid!
Even at the limit, with the front wheels sliding sideways in a turn or
locked under braking, the rear wheels gave positive control all the time,
leaving me nothing to investigate! Peter Bates, Chertsey's Deputy Facilities
Manager, came along for the ride and said afterwards: 'We've seen a lot of
vehicles on here, but nothing like this - the handling is amazing'. This
adds to all the other evidence that shows that Glynne was right - this
really is the best way to steer Thrust SSC.
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