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Model #3 brakes: electromechanical. No more fluid?

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Hadn't seen that. While feasible, sounds expensive with all the sensors and redundancies required.

The Differences Between Hydraulic and Electromechanical Brakes

Looks like Hitachi offers a system:
http://www.hitachi-automotive.us/Products/oem/DCS/BrakeSystems/index.htm

We will see. Removing yet another fluid-based, hygroscopic system with seals that age, would be great.

Chassis
  • Double wishbone, virtual steer axis front suspension with coil over twin-tube shock absorbers and stabilizer bar
  • Independent multi-link rear suspension with twin-tube shock absorbers and stabilizer bar
  • Variable ratio, speed sensitive electronic power steering
  • Electromechanically boosted four wheel anti-lock disc brakes with electronic brake force distribution
  • 18” Aero or 19” Sport wheels with all-season tires
 
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We will see. Removing yet another fluid-based, hygroscopic system with seals that age, would be great.

Chassis
  • Double wishbone, virtual steer axis front suspension with coil over twin-tube shock absorbers and stabilizer bar
  • Independent multi-link rear suspension with twin-tube shock absorbers and stabilizer bar
  • Variable ratio, speed sensitive electronic power steering
  • Electromechanically boosted four wheel anti-lock disc brakes with electronic brake force distribution
  • 18” Aero or 19” Sport wheels with all-season tires
I wonder what the word "boosted" means. Does Boosted mean that its helping and/or assisting the hydraulic?
 
We will see. Removing yet another fluid-based, hygroscopic system with seals that age, would be great.

Chassis
  • Double wishbone, virtual steer axis front suspension with coil over twin-tube shock absorbers and stabilizer bar
  • Independent multi-link rear suspension with twin-tube shock absorbers and stabilizer bar
  • Variable ratio, speed sensitive electronic power steering
  • Electromechanically boosted four wheel anti-lock disc brakes with electronic brake force distribution
  • 18” Aero or 19” Sport wheels with all-season tires
Yes, removing fluid cuts down on maintenance and not having to route brake tubing during production would save labor and possibly weight. Just plug and play harnesses and install the major components. Intrigued to say the least.
 
I suspect these are hydraulic brakes with electric boost/control (as opposed to vacuum assist in ICE vehicles), very similar, if not the same, to the Bosch iBooster used in the Model S.
This. The specs say electromechanically boosted and the iBooster is an electromechanical hydraulic brake booster... as opposed to traditional vacuum boosted hydraulic brakes.
 
Confirmed by a service tech - the model 3 does use brake fluid.

Also confirmed by the fellow that roasted out his brakes pads and cooked off some of the fluid on the race track. Model 3 Track Day: Laguna Seca :cool:

However, from visual inspections from underneath, the rear brakes at least seem to have an redundant electro-mechanical means of engaging the calipers. This is the "emergency brakes". On the S/X this was, IIRC, done via a 2nd set of calipers per wheel.
 
Any car with Stability Control has electromechanical assist.

You won't see non-hyd brakes for awhile if ever.
First they'd have to be 'always on'. If you have a power issue, the brakes must engage. This can make for some fun times when working on a car. You want to disconnect the battery to work on the brakes, but you could not. It won't roll well either if there is an electrical issue.
1.5 - If the brakes are 'always on' like airbrakes on trucks, trains, and heavy equipment, you have to waste electricity constantly.
Second is hyd lines and calipers are cheap, light, with analog feedback.
Third would be regen. Electric cars have the best of both. Virtually no additional weight for 'electric' braking, but you always have your backup hyd system just in case.
 
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First they'd have to be 'always on'. If you have a power issue, the brakes must engage.
Yeah, hydraulic brakes have a fail-safe in that even "power braking" is usable to some extent without the power assist. That's really hard to duplicate on electro-mechanical braking without a fail-close of the calipers that by itself could be problematic. Your brakes engaging suddenly with no way to disengage them is a pretty daunting, squirrel situation under which to maintain vehicle control and not get smoked.
 
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Yeah, hydraulic brakes have a fail-safe in that even "power braking" is usable to some extent without the power assist. That's really hard to duplicate on braking without a fail-close of the calipers that by itself could be problematic. Your brakes engaging suddenly with no way to disengage them is a pretty daunting, squirrel situation under which to maintain vehicle control and not get smoked.

Large trucks all have air brakes. They were developed for trains (Westinghouse made his fortune, and was good friends with Nikola Tesla, not the car, the scientist) because it was hard to keep the brakes reliable with many cars, and you needed brakemen to physically operate the brakes by hand wheel. By making them Always On without air pressure, if something broke or came loose, the train would stop, and brakemen stopped getting killed and maimed. IIRC. Something like that at least.
 
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Large trucks all have air brakes. They were developed for trains (Westinghouse made his fortune, and was good friends with Nikola Tesla, not the car, the scientist) because it was hard to keep the brakes reliable with many cars, and you needed brakemen to physically operate the brakes by hand wheel. By making them Always On without air pressure, if something broke or came loose, the train would stop, and brakemen stopped getting killed and maimed. IIRC. Something like that at least.
Yup, if there is a separation in the middle of your chain of rail cars because a link failed or something then fail-close is VERY MUCH what you want. Especially if you're coming down grade...or going up grade and those loose cars start heading backward down the track who knows how far (and potentially into the face of a train that's expecting the train ahead of it to be going forward). Not much concern about steering there. ;)

Similar with large trucks/buses in that concern about what you'll plow into if you don't slow down right damn now is more a concern than any lose of maneuvering due to the brakes kicking in hard.