http://www.autoweek.com/apps/pbcs.dl.../61106011/1024

 

Interesting article. With all the other improvements on cars using electrical components, it is a wonder that brakes haven't been modified yet.

 

In some ways, these act like servo drum brakes - rotational force from drum/shoe friction increases the pressure of shoe on drum. If you have ever had to stop hard while backing up in a car with all drum brakes and no power boost, you might remember how much harder the brake pedal needed to be pressed. That's becaues there is no servo action going backwards. Current disk brakes have nothing equivalent to drum/shoe servo effect - for any sizeable vehicle they need a power boost. These wedge/disk brakes give servo action for disk brakes - cool.

But using electric power at the caliper rather than hydraulic is whole separate issue. Electronics have become pretty reliable and hydraulics can fail. But hydraulics rarely fail without warning, while electronics sure can. I have a BMW motorcycle with brakes boosted by an mechanically and electronically controlled pump. When that thing is off, it really takes a strong pull on the lever to stop - the bike goes from being able to do a "stoppie" with one finger to taking a crushing pull for an ordinary rapid stop. BMW is dropping that design starting this year.

Another problem I have with that article is the statement that this new brake design can cut stopping distances by 50%. Tire/road friction will not be increased and so there's no way stopping distances can be reduced by 50% - at least not compared to current brakes in good condition.

This does look like a major advance, but why the exaggeration?

Allen