Howdy,
No, I won't subject a non driver to this, tech would really get me
for that one, (Hmmm I can get a false drivers license off the internet,
somehow convince a nondriver that it can be done, and turn him loose with a
car I spent a year or better building......Nah I don't think so)
the vehicle I have been designing has even less track at the rear
than the front, 24 inches front, 8 rear....
as to forces on tires and moment axis front versus rear...
wheel torque, aligning torque, positive inclination angle, wheel
plane, direction of wheel heading, tractive force, direction of wheel
travel, positive slip angle, spin axis, lateral force, normal force,
overturning moment, rolling resistance moment. are these the forces I
should study?
The forces and moments imposed on the steering system emanate from
those generated at the tire-road interface. These forces are measured at
the center of the contact with the ground and provide a basis by which to
analyze steering reactions. they do not change if the steered wheel is
front or rear.
a kids' wagon has steering which has been banned at the Salt, and
so would not represent real world conditions....
And I have a few supporters of this concept....
At 06:24 PM 5/25/00 , you wrote:
>OK John...it sounds to me like you're going to build this thing no
>matter what!!!
>I don't have time to explain how caster is different on the rear than on
>the front. It's taken me over 50 years to learn the "little" that I
>have. Go buy every book you can that pertains to racing front and rear
>suspension. Then put them all into practice, then maybe you will learn
>what the differences are in front and rear caster.
>I realize you aren't going around corners at B-ville, but you sure will
>go around in circles.
>Are you going to find some one who has never driven a car before to
>drive this for you?
>When you have a wider track in the rear of your rear-steered car and the
>more you get out of shape, you can't power it back straight. It won't
>work. Go get your self a kids wagon, turn it around backwards, hook it
>to your car on a 20 ft. pipe, have someone pull you down the road at 50
>MPH and see how straight you go by steering the rear.
> If we're lucky we get to race at B-ville once or twice a year.
>Everyone on the list that has nixed this idea has seen some of these
>problems.Why compound all the other problems that we encounter in Land
>Speed Racing by doing something that no one has really made work well
>yet?
>
>john robinson wrote:
> >
> > Howdy,
> > OK, I want to hear how caster works differently rear compared to
> > front..... and if your rear steer steers with a wider track, so what? we
> > are not making corners here(sorry, I mean on the Salt), as to Davenports'
> > lakester, isn't that one a rear drive car? this will make a big
> > difference...So far we've been discussing FWD rear steer, something that
> > has weight forwards which will cause the rest of the vehicle to follow a
> > lot easier than the rear drive weighted vehicles that spin easy . I grant
> > it is not a "natural" feeling driving a rear steer, but it would be, if you
> > had not driven anything else......
> >
> > At 02:14 PM 5/25/00 , you wrote:
> > >Hi List:
> > >O.K. guys.. I'll put my 2-bits in here. Rear Steer-no-no-no-no and then
> > >again no..ha ha
> > >Think about it..when you go into a corner which wheels get there first?
> > >The front (most of the time). If you are steering with the rear wheels,
> > >you have to start steering sooner than normal and your rear wheels will
> > >take a wider track than your front wheels. This is not a natural feel
> > >or reaction. Even if you have 10,000 HP to pull the rear of the car, it
> > >will not go straight. You will have to steer it. We have already heard
> > >about overcorrecting problems and the faster you go the more they are
> > >multiplied. Also, caster works different on the rear than on the front.
> > >And it would take to long to explain it here, but it is way different.
> > >Les Davenport says that the lakester can get 15 degrees off straight at
> > >300 MPH so quick that even with rear wheel power it's hard to handle.
> > >Just think what it would be like if you had no power to the rear wheels
> > >and were trying to steer with them!!
> > >We all like new ideas and want to try to make something work that others
> > >can't, but this is definitely a no-no.
> > >In 1997 there was a front wheel drive modified roadster, rear steer at
> > >B-ville. I watched the car try to make a couple of passes. It had an
> > >axle in back with about 20 degree caster in it. I don't think they even
> > >got a full pass on the car. We watched it from the starting line and the
> > >car was all over the course,.
> > >Just my humble opinion, but I wouldn't spend time trying to make it
> > >work.
> > >Russ #902 M.R.
> > >The Garbage truck motor man.
> >
> > 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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