This is a most excellent place for technology news and articles.
Brembo’s new “Sensify” braking system takes that one step further, eliminating the hydraulic system entirely and relying instead purely on electronic brake-by-wire and electric motors
OK now show us a scenario where the vehicle is badly damaged in a traffic collision, the electrical system is compromised, (possibly even on fire) and show me the vehicle slowing to a stop safely with no electrical systems functioning what-so-ever or GET OUT OF HERE WITH THIS INSANITY
I'm with you, but playing devil's advocate... A hydraulic brake line can be damaged in an accident as well. Simple brakes with a proportioning valve or similar mechanism likey doubles your redundancy for most failures of downstream brake components but that's not guaranteed.
It does say electric motors are a part of the system which could be like the electronic parking brakes in many modern cars. Maybe they default to a closed/braking condition if power is lost?
I will not be the one risking my life or my family's life or the lives of other families to be an early adopter of this tech, but it could work with rigorous engineering and testing.
Oh I'm with you there, but hydraulic hard lines and high pressure brake lines are thousands of times more rugged than electrical wires and cannot be rendered useless by software mistakes or operating system crashes. The ABS controller, computer functions of a regular car can fail catastrophically, the vacuum system can be breached and made useless, but the hydraulic brake pedal is still capable of slowing a car to a stop.
"I'm sure this will end well." -Absolutely nobody, anywhere
In fact, according to BMW, drivers of current EVs pretty much never activate their mechanical braking systems, relying instead on their electric motors to handle the job.
I didn't think the regen could bring a car to a complete stop, like at a stop sign or a red light. They're certainly not using the motors to hold your place on a hill, are they?
Or are they just saying BMW drivers never stop when they're supposed to?
I mainly use it, but I i definitely have to use the brake when i need to get less speed or in an emergency. My car does roll forward automatically and engine brake automatically too.
Yes I use regen braking for nearly all my stops at lights and stop signs. I’d say 80-90% of the time.
I never apply brakes when on a hill, as regen braking covers that to.
I never apply brakes when on a hill, as regen braking covers that to.
But what about coming to a complete stop on a hill? There's no way for regen to do that, there has to be motion for it to work.
Do you know for a fact that your car (in "B" mode or whatever it is you're using) doesn't engage mechanical brakes on your behalf when appropriate? Or is this an assumption?
Well that sounds terrifying. There's a reason why the brake hydraulicsystem is actually two separate hydraulic systems, for diagonally opposite wheels. The only single-point-of-failure is the brake pedal.
Their leaving out the critical details on how this will electric system will be fail safe, or even legal.
The announcement was light on details about both the system itself and how its fail-safes are implemented.
Maybe they'll return to spring actuated mechanical brakes that are released when everything is working. (More common in heavy industry, and I believe also truck brakes)
Come with me on an ADHD journey!
Spring actuated, or well, any type of ‘fail closed’ brake design would definitely work.
But what happens if it fails closed (due to no power - the only failure mode I’ve considered below) and the vehicle needs to be moved?
Are they gonna do that thing they do with elevator emergency brakes with the spinning balls that engage the brakes only if a certain inertial threshold is reached? That way as long as they aren’t going too fast, the car can be pushed off the road?
Or are they gonna let you plug in a phone to charge the brake system enough to disengage the failsafe?
Maybe there will be a sweet-ass lever under the center console like the one in the first Jurassic Park movie where people have to pump it to prime the system?
My favorite iteration of this nonsensical idea is that new cars are going to come with a crank in the front, like old-school model T’s, so that in an emergency, people can wind up their cars to release the brakes.
(Please consider all of the above as me having too much time on my hands, and not a real critique of your statements. I think failsafes are a good idea. I’m just a silly.)
Diagonally opposite? No, it's front and rear. However, brake fluid reservoirs haven't been split for decades now, so if your fluid leaks out, every wheel is affected. It's still highly unlikely that you're going to have a leak that suddenly dumps all the fluid, unless you're driving a very old and rotten car, in which case you probably know what you've gotten into.
Brakes that "fail on" while the vehicle is moving can be catastrophic for some dingus in a car. Truck drivers have much more intensive training and specialized licensing.
Hydraulic brakes in a car will still stop the car in a relatively controlled fashion even if the system is incredibly degraded, and they are purely mechanical. With wires, there's a chance that the brakes go from "working normally" to "not working at all" without any warning. Hydraulic brakes fail gradually.
No. It is diagonally opposite. All rear will cause the veichle to fishtail and similar issues with all front braking in case of failure. Thus the parking brake is infact not an emergency brake but a parking brake.
Show me one car that has diagonally opposite hydraulic brakes. I dare you.
They're all split front/rear because the different axles provide different braking power. Most of the braking happens in the front; rear is primarily for stability. When you press the pedal, in fact, the rear brakes engage slightly before the front in order to add stability while braking.
Here’s an entire manufacturer: Seat
Interesting, I was unaware of that one.
I'll look more into it later, learn about its failure modes and whatnot, but off the top of my head, it seems like it would still be a less effective system. I think I would much rather have one axle working. That mitigates the case where the two wheels are on different frictional surfaces, which could leave you with just a single wheel braking.
And still, if the fluid reservoir is a single undivided container, I'm not able to imagine a case where two wheels - horizontal or diagonal - would fail at once.
The only single-point-of-failure is the brake pedal.
And even then, only on cars with those stupid electronic parking brakes instead of a proper mechanical emergency brake.
Preach! Looking at you, Nissan. Need a computer to change brake pads. Are you outta your goddamn mind?
Pulling the handbrake on a moving vehicle is generally speaking really bad idea. It'll stop, yeah, but it'll be really scary for a moment before that.
