This is a very interesting topic to me. Where can I find more
information about the ABS? And the VSC? How did people at LEXUS mixing ABS
and VSC? I'll be working on this subject soon, so I'll need all the
information I can. There are some interesting articles in the SAE web
(http:\\www.sae.org), but I need more information.

   Thanks.

-----Mensaje original-----
De:     Wayne Foletta [SMTP:wayne@ELECTROTEK.COM]
Enviado el:     viernes 23 de enero de 1998 17:55
Para:   PICLIST@MITVMA.MIT.EDU
Asunto: Re: [Way OT] ABS brakes.

Oyvind:

Modern ABS systems use hydraulic pressure, temperature, and each wheel's
rotational velocity to compute a skid condition before it happens. The
brake hydraulic pressure is modulated and or reduced to equalize the
rotation of all wheels. Below a certain speed the ABS affect is near
zero (as when stopped or slowing to a stop from a low speed).
Many systems (like the Boeing 747 I worked on in the early 70's) use
cross or diagonal wheel (or wheel carriage or bogie) systems such that
even with a system error the braking fails to a balanced set of normally
braked wheels.

- Wayne Foletta
BMI - Saratoga, CA

> ----------
> From:         Oyvind Kaurstad[SMTP:oyvind.kaurstad@NOFAC.ABB.NO]
> Reply To:     pic microcontroller discussion list
> Sent:         Friday, January 23, 1998 4:11 AM
> To:   PICLIST@MITVMA.MIT.EDU
> Subject:      [Way OT] ABS brakes.
>
> This is way off topic, but it is related to electronics, and
> could theoretically be related to PIC's... :-)
>
> Modern cars have ABS brakes, which is a system made to
> prevent the wheels from locking up.
>
> This system have sensors on the wheels that senses whether
> it is rotating or not. Usually it is sensing on a toothed disk of
> some kind. (Probably some kind of hall-effect gadget)
>
> This is perfectly suited to sense if there is rotation or not.
>
> But here comes the interesting part:
>
> How can a car with ABS brakes come to a stop in a hill?
>
> Why don't the ABS-system release the brakes when the car stops?
>
> And now you might say that the ABS-system is deactivated below
> a certain speed, which is absolutely correct.
>
> But what if a car standing still starts to slide? Will the ABS-system
> be able to release the brakes?
>
> Just wondering....
>
>
> -Oyvind