Wedge brake system.

To sum it up, you still have the same way the car brakes. But the brake pads are not driven by a fluid as in todays cars, rather than by small electric motors.
 
nit quite, they're "driven" by the rotation of the wheel itself. the motors are only there to adjust the amount of brake pressure.
 
Ah well, I must admit I missed that bit before. But remembering the video, it does make some sense now. :p
 
i just watched the vid, i didn't understand how it was supposed to work before that either. ;)
 
I think there will be trouble getting good brake feel (Mercedes found that out using brake by wire even with normal brakes), and also they will have a very hard time getting linear brake application or smooth slow stops. For panic stops it looks great though.
 
Mad Cow said:
Can somebody explain this to me? I saw the video but still don't get how it works.:dunno:
Click to expand...

The actual friction mechanism works the same as disc brakes (you have two pads squeezing a disc to make it stop). The only difference is how the pads are pushed against the disc.

Normal disc brakes just push the pads directly inwards. This system instead moves them to the side (in the direction that the disc is moving). Since the pad is on rollers (watch the animation again), it's pushed inwards as it moves sideways.

The advantage of this system is that the disc will now pull the pads further forward, pushing them harder against the disc and sustaining its own squeezing force. This greatly reduces the work required by the calipers, so you can use low-power electric motors.

geoff_a_pult said:
I think there will be trouble getting good brake feel (Mercedes found that out using brake by wire even with normal brakes), and also they will have a very hard time getting linear brake application or smooth slow stops. For panic stops it looks great though.
Click to expand...

The system already has a torque sensor for the ABS system, so they should be able to get linear brake application as long as the motors can react fast enough (and I'm guessing they can; you wouldn't want sluggish brakes!). If they're clever, they'll use the torque sensor to drive the feedback through the pedal as well (i.e., the resistance in the pedal will be proportional to the amount of torque being applied to the wheels). They say the whole system is programmable, so I'm guessing that means it's possible to make it emulate the feel of hydraulic brakes.
 
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Okay, here's a mean one: what if you go down a slope backwards with a trailer, and you'd like to stop?? :p
 
Well in that case all your braking power is on the front wheels anyway and you will end up locking up and being dragged, depending on the momentum developed before you get on the brakes.
 
the Interceptor said:
Okay, here's a mean one: what if you go down a slope backwards with a trailer, and you'd like to stop?? :p
Click to expand...
The brakes will work exactly the same in that case, only the pads will move backwards instead of forwards. They'll still be pushed against the disc, since the rollers sit in V-shaped valleys:

Code: 
*At rest*

  ===================== <-- brake disc

  ????????????????????? <-- brake pad
  \*/\*/\*/\*/\*/\*/\*/ <-- rollers and slopes

*Braking while moving forwards*

  ===================== 
 ?????????????????????  
  *  *  *  *  *  *  *  
  \ /\ /\ /\ /\ /\ /\ / 

*Braking while moving backwards*

  ===================== 
   ????????????????????? 
    *  *  *  *  *  *  *  
  \ /\ /\ /\ /\ /\ /\ /
 
You're right! Thanks for the explanation (and the nice picture!). :wave:
 
but there's problems people! :D

1. if the electrics systems fail, there's no brakes at all - apart from the hand brake.

2. It's a full power brake - that means one thing - no feel!

3. Annnd these brakes look like that as the pads start wearing, it'll get loads closer to the point where they'll just skip to the next "valley"

oh and it'll be a lot harder to check if there are faults with the wires than if there are leaks in the hydraulic system.

Buuuuuut, there'll be less unsprung weight, less sprung weight, less force required to use the brakes and so on.


Although I'd much much MUCH rather have brembo written on my brakes than siemans.
 
Blythy said:
but there's problems people! :D

1. if the electrics systems fail, there's no brakes at all - apart from the hand brake.

2. It's a full power brake - that means one thing - no feel!

3. Annnd these brakes look like that as the pads start wearing, it'll get loads closer to the point where they'll just skip to the next "valley"

oh and it'll be a lot harder to check if there are faults with the wires than if there are leaks in the hydraulic system.

Buuuuuut, there'll be less unsprung weight, less sprung weight, less force required to use the brakes and so on.


Although I'd much much MUCH rather have brembo written on my brakes than siemans.
Click to expand...

1) Actually, if you look at it they take the handbrake out as well. (I'm guessing they intend to have the hand brake or e-brake system simply engage the rear brakes selectively), so if the electric system fails the e-brake will be gone too.
That isn't a real issue though, because it should be easy enough to design it with a mechanical interlock that steps in and makes the brakes apply when there isn't any electrical current. (That way if the electronics fail the car will automatically apply brakes and stop. Of course this could result in unexpected full lock-up braking at autobahn speeds, but that is probably better than finding out later you have no brakes)

2) Yup! You should be used to in by now though- every power system that has been added has taken a bit of feel with it. Active steering< Power steering< unassisted, brake-by-wire< normal hydraulics, turbo throttle response< NA. The future= Point the car where you want it to go, and it will. No feedback necessary.

3) The skipping to the next valley isn't an issue because in real life they will either simply design it so that the valleys retain the rolling pins when the pad is fully worn off, or they will design it so that the neutral position of the motors advances as the pad wears. It is a flaw in the simulation they created, not in the basic idea.

From what I understand, it will actually add a few pounds of unsprung weight as well, instead of decreasing it. If you look at the simulation, it has most of the components of a normal brake, plus the electric motors and the rollers and slopes. The only part cut out (correct me if I'm wrong) is the hydraulic fluid feed, which really has negligible mass.


It seems like a cool concept to me, but I don't see it panning out as a great development in sports cars' braking power for one reason-
Why aren't F1 cars running them yet?
 
ryosuke said:
arg, hopefully not!:glare:

i hate it, electronic brakes, electronic suspension, electronic differential, electronic steering, electronic acceleration, electronic engines...i want a goddamn car that smokes, squeals, locks ity tyres up, slides, does burnouts and i don't want it to fail when i switch on my mobile.;)
Click to expand...

then get a miata.
 
1) Actually, if you look at it they take the handbrake out as well. (I'm guessing they intend to have the hand brake or e-brake system simply engage the rear brakes selectively), so if the electric system fails the e-brake will be gone too.
That isn't a real issue though, because it should be easy enough to design it with a mechanical interlock that steps in and makes the brakes apply when there isn't any electrical current. (That way if the electronics fail the car will automatically apply brakes and stop. Of course this could result in unexpected full lock-up braking at autobahn speeds, but that is probably better than finding out later you have no brakes)

I myself would put a spring in somewhere as a failsafe. Also legislation says that there must be a mechanical parking brake.
 
Its not that it will suddenly be on all cars and you dont have a choice anymore. Just give it a chance, see how it works and then judge. All the problems can be solved and it doesnt necessarily have to have no feel. Also its not quite right that all old cars without power assistance had more feel than new ones. The normal car for everyone today is a lot better to drive with a lot more feel to it than it was in the past. World doesnt only consist of expensive sports cars.
 
Without watching the video or looking at the pictures, I have arrived at the conclusion that this system is crap for the standard auto. How often do you have to stop from 200 on a day to day basis? Furthermore, braking in most cars with ABS is already at the threshold of what the car and its tires can withstand. More braking power will make no difference whatsoever; if manufacturers want to decrease the braking distance for cars, give us 4-wheel disc as standard, with better tires.
 
ryosuke said:
arg, hopefully not!:glare:

i hate it, electronic brakes, electronic suspension, electronic differential, electronic steering, electronic acceleration, electronic engines...i want a goddamn car that smokes, squeals, locks ity tyres up, slides, does burnouts and i don't want it to fail when i switch on my mobile.;)
Click to expand...


i agree in essence, but i think that overtime people will be able to get character out of these components, especially if the italians spend enouph time with them

as a person who drives a car that fits your description above, i am concerned about the overuse of electronic parts, if its no good we'll probably go back to mechanics, if you do your research you'll find that, for instance, electric cars came out before gasoline driven cars, doesnt mean that just because it was "more advanced" that we kept that technology, it simply didn't work


im the most worried about electronic steering, most (american) car companies cant get proper steering feedback with mechanics, how the hell am i supposed to know what the front tires are doing with poorly tuned electronics?
 
I believe it to be a good thing. I'm sure its going to be loaded with safeties so there won't be any failure of brakes. This will be better for the average driver who doesn't know anything abour cars, unlike many on this fourm who have some clues.
Even though it will take the feel out of the brake system and make it harder to feel the car, if you wanted to drive on a track you simply wouldn't have this car because it wouldn't be fun.
The whole point of all these electronic systems is to try to make driving easier by having ESP, TCS, so in extreme conditions you will be able to drive.
Bring on innovation!
 
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