Fly-By-Wire Gas Pedal for better speed control

Discussion in 'General Motoring' started by Nomen Nescio, May 12, 2006.

  1. Nomen Nescio

    Nomen Nescio Guest

    Most of us have become aware it is rare for a fatal accident not to be
    felonized. It used to be unless there was wanton disrespect for laws, life
    and property, an automobile accident was just that, an accident. Civil,
    not criminal laws applied. Today, if you are overspeeding, easily proved
    from your car's tell-tale chip, and you cause a fatal, you will be
    prosecuted for vehicular manslaughter.

    Given that, your car should be reducing your driver workload to stay legal.
    That is not the case. Your gas pedal is working overtime to make speed
    control next to impossible. Compared to older model cars, the modern gas
    pedal is far too sensitive. Press it down 15% of its travel and your car
    does not pick up to 15% of its top speed; it will likely do 85 mph! This
    fault makes it hard not to gradually pick up speed unconsciously on an
    extended drive, where your foot "gets tired." You should not have to
    constantly monitor the speedometer to keep from creeping up in speed. Most
    drivers cannot help but speed up, slow down, and cycle that way for the
    whole road trip. Cruise control, the auto-makers' solution, is like a
    Microsoft patch, something to fix a defect that never should be in the

    A solution is a fly-by-wire throttle. The car's computer can do wonders
    with this idea. Here's how it would work:

    The computer constantly monitors your car's performance and adjusts the
    sensitivity accordingly, just like your CD burner tests read performance
    before you rip your favorite music to a CD-R. Thus, it adjusts pedal
    sensitivity according to car load, outside temperature, pressure, effect of
    gradient, rolling resistance, gas octane, etc. from a default baseline.
    This is not as hard as it sounds. From the throttle position sensor, MAP
    sensor, incoming air temp sensor, etc. it gets all that data. The only
    other sensor needed is an accelerometer. The computer would calculate
    everything and then adjust the gas pedal potentiometer signal to make the
    pedal LINEAR. Thus, press down 50% of pedal travel and your car will go
    50% of its top speed under the conditions. So, if the top speed of your
    loaded car is 75 mph on a steep mountain grade, pressing down 50% will
    yield about 40 mph. Also, there can be force feedback on the pedal to
    further enhance control. Too light a pedal makes for a sinking pedal and
    speed creep. A linear solenoid or torque motor could be computer
    controlled to increase pedal resistance with increasing pedal depression.
    This feedback is in contrast to the featherweight pedal at any position in
    current setups. Force feedback makes for excellent control cues to the
    right foot.

    There would be a world of difference between the above described gas pedal
    and the one in your present car. Speed and power would be far easier to
    control and most importantly, maintain homeostasis. Unintentional
    overspeeding, a prime factor in accidents would be largely eliminated.

    Attorneys: The car can be blamed in court for unintentional overspeeding.
    This is a viable defense for valid engineering deficiencies built into
    today's models. Gas pedal setups in all cars of the last 25 years are
    ultra-low ratio; that is, a small movement of the pedal causes a large
    movement of the intake manifold air-flow valve and results in an
    oversensitive pedal. The reason for this faulty design decision is due to
    competitive sales forces at work. That car which is perceived to be more
    powerful, sells. Any car can be made to seem more powerful by rigging the
    pedal so a little touch cracks the air-flow valve wide open.
    Unfortunately, control suffers from this unethical ruse.

    There is also a problem with ultra-low ratio steering, but I will address
    that in a later post.
    Nomen Nescio, May 12, 2006
  2. Nomen Nescio

    Whoever Guest

    Did I not just read a post by you where you were advocating junking modern
    electronic engine and transmission management in cars?
    Whoever, May 13, 2006
  3. WHAT?!?!? A post from Nomen regarding automotive electronics that
    not one single time compares auto systems to airplane systems?

    He must be getting ill, call the doctor!

    Ted Mittelstaedt, May 13, 2006
  4. <top post>

    Everybody should be able to easily FEEL what the foot is causing the engine
    to do, and the eyes should SEE what the car is doing relative to the ground.
    Speeding is speeding, and is ONLY a result of the foot being a bit to
    aggressive, and the eye a bit too blind.
    </top post>
    Jeff Strickland, May 13, 2006
  5. Nomen Nescio

    Matt Whiting Guest

    Yes, Nomen is out to lunch as usual. However, I will say that I'm not a
    fan (yet, anyway) of the throttle-by-wire systems. Maybe after some
    further development. I have a new Sonata (yes, I realize it isn't a
    Chrysler) with an electronic throttle and standard shift. The throttle
    is very light (no feel as with conventional throttles) apparently due to
    very light springs, the engine is very quiet, and the clutch is also
    very light compared to other standard shift vehicles I own (Chevy K1500
    pickup and Jeep Comanche pickup) or have owned in the past (everything
    from VW Beetles to an Opel Manta).

    This makes starting out smoothly a real challenge. It is hard to feel
    or hear what is going on and it is hard to watch both the tach and
    traffic at the same time. And the engine, while quite powerful when
    revved, has very little torque below 1200 RPM. So, unless you want to
    wear the clutch by revving to 2000 before engaging it, it is all too
    easy to stall it.

    Matt Whiting, May 13, 2006
  6. Nomen Nescio

    philthy Guest

    d c told us in obd training that the a set of electric motors was cheaper
    than a cable and throttle body gm has been using this electric throttle since
    philthy, May 14, 2006
  7. Nomen Nescio

    hartless Guest

    Your Hyundai is using a electric throttle!
    hartless, Jun 22, 2006
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