Liam..... your jumps in logic are....... interesting!
Two articles from Wikipedia cover this discussion. I have claimed that ‘rocking’ between locked and unlocked WORKS as a way of improving braking. The fact that modern ABS need NOT involve ‘locking’ (and that’s not at ALL clear from your posting) does NOT deny that it still WORKS when you lock ‘instantaneously’
Here's the section you need:-
"Early ABS
Anti-lock braking systems were first developed for aircraft use in 1929, by the French automobile and aircraft pioneer, Gabriel Voisin, as threshold braking on airplanes is nearly impossible. An early system was Dunlop's Maxaret system, introduced in the 1950s and still in use on some aircraft models.[2] These systems used a flywheel and valve attached to the hydraulic line that fed the brake cylinders. The flywheel was attached to a drum that ran at the same speed as the wheel. In normal braking the drum and flywheel would spin at the same speed. If the wheel slowed suddenly the drum would do the same, leaving the flywheel spinning at a faster rate. This caused the valve to open, allowing a small amount of brake fluid to bypass the master cylinder into a local reservoir, lowering the pressure on the cylinder and releasing the brakes. The use of the drum and flywheel meant the valve only opened when the wheel was turning. In testing, a 30% improvement in braking performance was noted, because the pilots immediately applied full brakes instead of slowly increasing pressure in order to find the skid point. An additional benefit was the elimination of burned or burst tires."
http://en.wikipedia.org/wiki/Anti-lock_braking_system
You'll note that the ORIGINAL ABS system involved LOCKING the wheels momentarily.... as I said from the beginning!
I have NO DOUBT that modern ABS works much better than the old systems.... however, this does NOT deny that the earlier systems were NOT so subtle and used EXACTLY what we were discussing.... a brake system which 'rocked' between FULLY locked and 'partially locked'..... in such vehicles....... the wheels REPEATEDLY lock!
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BUT
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I just noticed ONE comment within that article: 'threshold braking"
It's NOT a term I have heard mentioned before..... but I find it EXACTLY matches what I have been describing as 'semi-lock' and it does EXACTLY what I have been CLAIMING for it!
"http://en.wikipedia.org/wiki/Threshold_braking"
OK..... in karting, we are more BRUTAL (or subtle) with it but it COMPLETELY confirms what I have been claiming from the VERY FIRST MOMENT of our discussion......! We karters CAN reduce our braking distance by using this ‘semi-lock/threshold’ braking technique…. which you seem to have doubted!
This is a Woody Allen: Annie Hall/cinema queue moment.......!
Perhaps modern ABS CAN do it better…. So what... for the terms of this discussion about karts?
Ian
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