If ABS works by comparing wheel speeds
11-21-2004, 04:36 PM
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If ABS works by comparing wheel speeds
How can you drive in a straight line, press the brakes (not hard), and pull the handbrake (making the rear wheels lock and thus having a huge difference in speed between the rears and the fronts) without having the ABS go psycho?
11-21-2004, 04:54 PM
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ABS should be much more simple than this. iirc the basic concept is to keep the wheels from locking
up so you can maintain steering. I'm not sure exactly how the audi system does it, but I don't think it is overly complicated. If anything I would think that you would have to worry about the esp going crazy if you pull the ebrake (parking brake) while in motion.
11-21-2004, 05:04 PM
#4
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e-brake is mechanical...
Doesn't matter what the program does, you are overriding it with a mechanical system. I'm sure the ABS computer is screaming, but what can it do?
11-21-2004, 06:47 PM
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Reexamining.
You are applying some pressure to the brakes. ABS is monitoring for wheel lockup. You pull the parking brake, applying a disproportionate amount of brake force to the rear wheels, causing them to lock up. Shouldn't you feel pulsing as ABS releases the brake system's hydraulic force to the rear discs in order to unlock the wheels (even though it can't) since the fronts are still spinning?
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11-21-2004, 06:54 PM
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Also good. Honestly, I don't think the ABS would 'do' anything in that situation- It would (m)
percieve the rear wheels as having locked up, and trigger the ABS, but since they're stopped by an external force, there's nothing it can do about it.
