Hi John;
Two or three years ago I wrote the technical committee a letter with a
proposal for a rear steer 500CC streamliner. The reply I received was from
John Bjorkman who I believe was head of the tech committee at that time. The
gist of their analysis was that the concept would rely to much on the
traction available to the rear wheels for stability. I failed to see any
difference in the traction availability front Vs rear steer because if you
loose traction the center of gravity try's to get ahead of the center of
lateral pressure and the car spins. I believe the great bias of weight on
rear drive cars is what causes them to be unstable and require devices like
fins and wings to keep them straight. The rule book now defines an
automobile as having front wheel steering, a concept that the FIA does not
embrace.
Jim in Palmdale, who got over it long ago.
----- Original Message -----
From: john robinson <john@engr.wisc.edu>
To: Jim Dincau <jdincau@qnet.com>
Cc: <land-speed@autox.team.net>
Sent: Wednesday, May 24, 2000 1:48 PM
Subject: Re: Fuel and Gas Class
> Howdy,
> ummm, whom have you been talking to about the rear steer
concept?
> I have not been told I can't do it, but that I could expect MANY
inspectors
> investigating the vehicle when it hit tech inspection. The word I have
> gotten from Alan Fogliadini is that no one can say I can't do it, but that
> I should PLEASE take their ADVICE and not do it, due to the many unknown
> and therefore possibly unsafe conditions that may arise from the testing
of
> the vehicle. At this time I am continuing with this as a concept only, but
> I still wish to leave open an option to build it.
> I also agree with your brother, those are the same reasons I was
> attracted to this concept. I have some drawings now and >may<, after this
> Speed week, begin building it, although I still wish to discuss this more
> with as many people as possible while at the Salt before welding anything
up.
>
>
> At 03:13 PM 5/24/00 , you wrote:
> >My brother is convinced this concept can be made to work in a streamliner
> >with the right design. Driving the front wheels and steering the rear
allows
> >a less complicated compact design that keeps the maximum weight over the
> >drive wheels, keeps the cg ahead of the lateral center of pressure,
reduces
> >the wetted area and requires the least compromises in streamlining. The
tech
> >committee won't even let us try it with a test mule so I guess we will
never
> >know.
> >Jim in Palmdale, where it has been 90 Deg. at 10 AM and 70 Deg. at 3 PM
> >with 30 MPH gusts .
> >
> >
> >
> >----- Original Message -----
> >From: john robinson <john@engr.wisc.edu>
> >To: dahlgren <dahlgren@uconect.net>
> >Cc: <land-speed@autox.team.net>
> >Sent: Wednesday, May 24, 2000 12:12 PM
> >Subject: Re: Fuel and Gas Class
> >
> >
> > > well, my thoughts were that the car is very narrow, 27 inches or so,
with
> >a
> > > long tapered tail that was not just empty space....
> > >
> > > At 01:55 PM 5/24/00 , you wrote:
> > > >I am losing something here the big speed secret and obvious advantage
of
> > > >rear steer is ????????????????????????????????????
> > > >Dahlgren
> > > >
> > > >john robinson wrote:
> > > > >
> > > > > Howdy,
> > > > > well now lets see..............
> > > > > ifn you take a long narrow streamliner with the front
wheel
> >drive
> > > > > non steering, and put the driver behind the engine, and then
behind
> >him the
> > > > > staggered rear steering wheels with only about 8 inches track, you
> >would
> > > > > use a mustang steering rack(#1) between the two rear wheels, and
then
> >take
> > > > > two mustang steering racks and weld them together so the driver
input
> >would
> > > > > go forwards, then backwards to the actual steering rack
#1),( which
> >would
> > > > > reverse the steering, the steered wheels would turn left as the
driver
> > > > > turned his wheel right, making the car GO right. )
> > > > > The kicker is that there is a delay between what the
driver
> >feels,
> > > > > and his input, which can produce a pilot induced oscillation as he
> >tries to
> > > > > catch up to the actual motion of the car. This motion is
considered to
> >be
> > > > > at about 1 Hz (the driver makes a correction, the car SLOWLY
begins to
> > > > > respond, the driver inputs additional steering,because he "feels"
that
> >the
> > > > > car is not responding correctly, then he finds the car to be
> >correcting too
> > > > > quickly and he reverses his inputs, always chasing the vehicle,
and
> >causing
> > > > > finally an out of control situation. This can be seen when
watching a
> > > > > single engined taildragger pilot learning to taxi the airplane for
the
> > > > > first time.
> > > > > However, I believe a disciplined driver CAN control a
> >vehicle
> > > > > designed with rear steer. I think that if the driver is in the
middle
> >of
> > > > > the car, rather than the end, he would feel less steering input
from
> >the
> > > > > motion of the car, thereby would not feel the need to input
> >corrections,
> > > > > and would not begin the PIO described above.
> > > > > Wasn't the car Beckett drove a sports car of some sort? a
> >short
> > > > > wheel base, wide track, mid engine something? I think this would
be
> >very
> > > > > difficult to try to rear steer, VERY little visual input available
to
> >the
> > > > > driver for corrections, which is why I thought the driver
positioned
> >in the
> > > > > middle of a streamliner would be advantageous, lots of car left in
> >front of
> > > > > him for visual reference, and less "feel" inputed to his butt than
if
> >he
> > > > > were in the tail of the car.
> > > > > The reference to Thrust' $2 million computer was to the
body
> > > > > positioning for aerodynamics, rather than controlling the actual
> >steering,
> > > > > this is information from the magazine articles I have seen.
> > > > >
> > > > > At 12:06 PM 5/24/00 , you wrote:
> > > > > >Now there is a Kernal of knowledge from Left Field.... Hey
John...
> >tell us
> > > > > >about this.... sounds interesting.. K
> > > > > >----- Original Message -----
> > > > > >From: John Beckett <landspeedracer@email.msn.com>
> > > > > >To: john robinson <john@engr.wisc.edu>;
<land-speed@autox.team.net>
> > > > > >Sent: Wednesday, May 24, 2000 12:08 PM
> > > > > >Subject: Re: Fuel and Gas Class
> > > > > >
> > > > > >
> > > > > > > John
> > > > > > >
> > > > > > > I think what Dan was trying to say is the rear steer has
been
> >tried
> > > > > > > before mostly unsuccessfully. I know cause I was one that
tried
> >it. The
> > > > > >only
> > > > > > > high speed success that I am aware off was the Thrust project,
but
> >they
> > > > > >had
> > > > > > > a $2,000,000. computer making the necessary corrections for
the
> > > > "pilot".
> > > > > >If
> > > > > > > you asked Andy Green today about rear steer I don't think he
would
> > > > offer
> > > > > >any
> > > > > > > encouragement for the concept.
> > > > > > > Another point I would like to make however, is that none
of
> >the
> > > > > > > governing bodies need to worry about adding rules to ban rear
> >steer
> > > > > > > vehicles. It just doesn't work at speed and I don't believe
you'll
> >ever
> > > > > >get
> > > > > > > it going fast enough to get into trouble. And if you do
somehow
> > > > manage to
> > > > > > > make it work, well God bless you, innovation is what it's all
> >about.
> > > > > > >
> > > > > > > John Beckett, LSR #79
> > > > > > >
> > > > > > > ----- Original Message -----
> > > > > > > From: "john robinson" <john@engr.wisc.edu>
> > > > > > > To: <land-speed@autox.team.net>
> > > > > > > Sent: Wednesday, May 24, 2000 9:57 AM
> > > > > > > Subject: Re: Fuel and Gas Class
> > > > > > >
> > > > > > >
> > > > > > > > Howdy,
> > > > > > > > ohhhh yeah, Definitions section IV-2 Automobile.(some
> > > > snipping) ....at
> > > > > > > > least 4 wheels not aligned....(snip).. steering assured by
at
> > > > least (2)
> > > > > > > > front wheels, .(snip) .....One pair must be on the same
> >transverse
> > > > > > > centerline.
> > > > > > > > OK, then the Special Construction Category statement
"Innovation
> >is
> > > > > > > > unlimited." is governed by the definitions sec IV?
> > > > > > > > John still looking at rear steer concept Robinson
> > > > > > > >
> > > > > > > > At 08:22 AM 5/24/00 , you wrote:
> > > > > > > > John,
> > > > > > > >
> > > > > > > > Also look at the portion defining automobile which indicates
> >that at
> > > > > >least
> > > > > > > > two wheels must be on the same axle. There is a statement
that
> > > > requires
> > > > > > > the
> > > > > > > > steering to be by the front wheels as our friends with the
rear
> > > > steer MR
> > > > > > > > found out a few years ago. Sorry I am unable to quote
chapter
> >and
> > > > verse
> > > > > >on
> > > > > > > > this one as my books are in my race day brief case.
> > > > > > > >
> > > > > > > > Dan (you can lose pistons without NOS too) Warner
> > > > > > > > ----- Original Message -----
> > > > > > > > From: john robinson <john@engr.wisc.edu>
> > > > > > > > To: <land-speed@autox.team.net>
> > > > > > > > Sent: Wednesday, May 24, 2000 5:42 AM
> > > > > > > > Subject: Re: Fuel and Gas Class
> > > > > > > >
> > > > > > > >
> > > > > > > > > howdy,
> > > > > > > > > Andy Green did it like that, only cost 30 million $ or so
and
> >took
> > > > > > > what,
> > > > > > > > > 6-7 years..........
> > > > > > > > > I think you >can< run in line wheels, just need to have
four
> >of
> > > > > >them(or
> > > > > > > > > more) ifn I remember the rule book on this
one....looking it
> > > > up now,
> > > > > > > aha!
> > > > > > > > > ...."must have at least four wheels, but they need not be
> > > > arranged in
> > > > > >a
> > > > > > > > > rectangular configuration" , Streamliner section V page
> > > > 41....is what
> > > > > > > the
> > > > > > > > > '00 rules say...
> > > > > > > > >
> > > > > > > > > At 10:13 AM 5/23/00 , you wrote:
> > > > > > > > > Should still work, maybe? Per the rule book the wheels
must
> >be
> > > > > >offset,
> > > > > > > > > cannot be inline. See Al teagues car. Otherwise isnit it
> > > > classified
> > > > > >as
> > > > > > > a
> > > > > > > > > "ahem" motorcycle or some such? But, adding the stagger
> >control to
> > > > > >the
> > > > > > > > rear
> > > > > > > > > does indeed work same as front stagger. Wow, what a
> >concept!!!
> > > > > > > Shouldn't
> > > > > > > > > take more'n ten years to sort it out...
> > > > > > > > >
> > > > > > > > > mayf
> > > > > > > > > At 02:39 PM 5/23/00 EDT, V4GR@aol.com wrote:
> > > > > > > > > >Won't work in Jacks car. Front wheels are inline. Have
to
> >switch
> > > > > > > system
> > > > > > > > to
> > > > > > > > > >rear wheels. Should work than. Rich Fox
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > > >
> > > > > > > > >
> > > > > > > > > L.E. Mayfield
> > > > > > > > > 124 Maximillion Drive
> > > > > > > > > Madison, Al. 35758-8171
> > > > > > > > > ph: 1-256-837-1051
> > > > > > > > >
> > > > > > > > > http://home.hiwaay.net/~lemay
> > > > > > > > >
> > > > > > > > > lemay@hiwaay.net
> > > > > > > > >
> > > > > > > > > Sunbeam Tiger, B9471136
> > > > > > > > > Sunbeam Alpine Bonneville Land Speed Racer,
> > > > > > > > > '66 Hydroplane Drag Boat (390 FE)
> > > > > > > >
> > > > > > > >
> > > > > > > > John Robinson, Mechanician
> > > > > > > > Mechanical Engineering University of Wisconsin
> > > > > > > > 1513 University Ave.
> > > > > > > > Madison, Wi. 53706
> > > > > > > > 608-262-3606
> > > > > > > > FAX 608-265-2316
> > > > > > > > Current World Land Speed Record Holder
> > > > > > > > Bonneville Salt Flats
> > > > > > > > H/GCC 92 cu.in. 1980 Dodge Colt
> > > > > > > > 131.333 MPH set 1995
> > > > > > > > 136.666 MPH set 1996
> > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > >
> > > > >
> > > > > John Robinson, Mechanician
> > > > > Mechanical Engineering University of Wisconsin
> > > > > 1513 University Ave.
> > > > > Madison, Wi. 53706
> > > > > 608-262-3606
> > > > > FAX 608-265-2316
> > > > > Current World Land Speed Record Holder
> > > > > Bonneville Salt Flats
> > > > > H/GCC 92 cu.in. 1980 Dodge Colt
> > > > > 131.333 MPH set 1995
> > > > > 136.666 MPH set 1996
> > >
> > >
> > > John Robinson, Mechanician
> > > Mechanical Engineering University of Wisconsin
> > > 1513 University Ave.
> > > Madison, Wi. 53706
> > > 608-262-3606
> > > FAX 608-265-2316
> > > Current World Land Speed Record Holder
> > > Bonneville Salt Flats
> > > H/GCC 92 cu.in. 1980 Dodge Colt
> > > 131.333 MPH set 1995
> > > 136.666 MPH set 1996
> > >
> > >
>
>
> John Robinson, Mechanician
> Mechanical Engineering University of Wisconsin
> 1513 University Ave.
> Madison, Wi. 53706
> 608-262-3606
> FAX 608-265-2316
> Current World Land Speed Record Holder
> Bonneville Salt Flats
> H/GCC 92 cu.in. 1980 Dodge Colt
> 131.333 MPH set 1995
> 136.666 MPH set 1996
>
>
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