DIYbanter - View Single Post - Snow Cover On Roof Provides Wind Protection?

Jim Yanik

(Doug Miller) wrote in
:

In article ,
(Don Klipstein) wrote:
In , Doug Miller wrote:

The thing that really stood out to me was the statement by Toyota's
president that they're going to look into programming a brake
override for the throttle.

I have only one question: WHY IN GOD'S NAME WAS THAT NOT THERE FROM
THE BEGINNING?

*Programming* a throttle override by the brake? As in relying on
lack
of electronic malfunction in order to have the brake reliably apply an
override onto the throttle?

Since the override becomes necessary only in the event of a throttle
malfunction, for the override to not work would require a second
malfunction. Clearly two simultaneous malfunctions are *far* less
likely than any single malfunction.

For additional safety, a mechanical interlock could be constructed --
but the electronic systems are more reliable.

under normal conditions,the operator would/should not be applying both
throttle and brake at the same time.

However,I question any need or benefit for throttle-by-wire(TBW) in an
auto.
the old mechanical throttle cable and throttle position sensor at the
butterfly works fine,and has less chance for malfunction,particularly on
newer vehicles.In fact,TBW is added complexity and cost,and more prone to
failure.
It violates the KISS principle,too.

As has been demonstrated by the Toyota SW problem,TBW can suffer
programming errors,SW glitches,or component malfunctions resulting in loss
of control of the vehicle.And there's no backup or redundant system as
there are in aircraft.A critical failure and your engine runs away.

after checking Wiki,I found these "benefits" for TBW;
"The significance of ETC is that it much easier to integrate features to
the vehicle such as cruise control, traction control, stability control,
and precrash systems and others that require torque management, since the
throttle can be moved irrespective of the position of the driver's
accelerator pedal."

IMO,if you need a computer to control your traction or vehicle
stability,you should not be driving. If your vehicle needs "stability
control",it's an inherently unsafe vehicle,and should not be on public
roads.

--
Jim Yanik
jyanik
at
localnet
dot com