Electric Handbrake / Emergency brake - Why? 10

[NickJ67]

Whats the reason for manufacturers moving towards electrically actuated, push-button handbrakes these days?

Having recently had to deal with one as fitted to the VW Passat, I have to say that it alone would prevent me from buying/leasing what is otherwise a pretty good car - such a pain to use when maneovering on a steep slope. I have also had the entertainment of watching my neighbor having to deal witha malfunctioning one on her Renault Scenic (non-release scenario).

Seems to me that they must be more expensive to fit and more prone to malfunction than a good old fashioned cable and lever arrangement - what am I missing? Am I a luddite....?

Regards

Nick

 

[jmw]

I today drove my brother in-law's VW something or other (Passat) 2litre TDi diesel.
This has 6 speed tiptronic automatic transmission.

I couldn't find an emergency/parking brake anywhere. It appears there is a button to press somewhere - I didn't have it long enough to work it out. It wasn't where Audi put their's....

I recall a time, long ago when my master cylinder failed (Mk1 Escort Mexico). So how did I stop? I used the gears and careful application of the handbrake.

What do you do when you have a parking brake... i.e. one of those press to apply and press to release brakes, or you have an electronic controlled brake?
I guess you get on your mobile phone to the police......


JMW

http://www.ViscoAnalyser.com

 

[evelrod]

As I recall in what started the recent Toyota recall, the "phone to the police" did not work out all that well!

Rod

 

[jmw]

Yes, that was in my mind when I posted. I guess if your brakes fail you are on your own.
Perhaps an ejector seat?

But it suggests that what we have with the electronic brake is a parking brake and that we now do not have an emergency brake.
Is that good?

JMW

http://www.ViscoAnalyser.com

 

[patprimmer]

The main braking system does have the second circuit for emergencies.

If my car was accelerating out of control I certainly would be looking for things to rub up hard against instead of waiting to crash head long into something.

Regards
Pat
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[NormPeterson]

Seems to me that the driver should always have ultimate override capability where getting stopped is concerned. If that means always being able to decouple the engine from the drive wheels in some fashion and having to then work through unassisted brakes, so be it. It should be the driver's responsibility to be aware of this possibility, in enough detail to let the rev limiter worry about keeping the engine intact in the meantime.


It would be worth knowing whether these electric/electronic P-brakes can even be applied at any speed, or if they are restricted to use under some nominal speed just to prevent the possible consequences of "unintended rear wheel only brake application".


Norm

 

[evelrod]

Again, here is a prime example of why we should have "proper" driver training and not what passes, at least in the US, as 'training'. Unlike my driver training, zooming around empty lots, dry lake beds, doing 'donuts' and bootleg turns just for 'kicks', today you get arrested. Too bad. It was a valuable education.

Without the experience of actually doing the things necessary to pull your arse out of deep do-do, how the heck do you expect results any different than the Lexus crash? I'm a member of the 'spun at high speed' fraternity. BTDT too many times, actually. Brake failure can be mitigated by, as Pat puts it, rubbing up against something. Better...Learn to control the car. Learn what to expect when you pull the wheel over hard at high speed. It's doable, trust me. It might just save your life one day.

Rod

 

[GregLocock]

"I may be a lone voice, but am of the view that we have gone way too far toward electronics, and in the process, sacrificed reliability and often, progressive failure (with warning), and many other characteristics inherent in mechanical controls for the programmability of electronic controls.For example, what is the cost / benefit of trading the tried and true ignition key (mechanical) with the electronic "start" button?What would be the tradeoffs of trading off the mechanical steering linkage with a electrically activated one?"

Well, you are an engineer, /you/ figure it out. Let's assume, just for laughs, that the people in the industry behave in a more or less rational fashion and don't eat LSD for breakfast.

Incidentally you can't buy a car with a purely electrically linked steering system, they all work even with no electrical power applied. That is an amazingly bad example for your argument, getting rid of the steering column and going all electric would actually be a positive for safety.


Cheers

Greg Locock


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[rmw]

Better...Learn to control the car. Learn what to expect...

until it becomes instinct.


rmw

 

[patprimmer]

It takes practice to make it instinctive and practice to keep it instinctive.

Practice can get you into a lot of trouble with the law. Don't ask how I know.



Regards
Pat
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[Gearloose1]

The issue of "all electric" steering was actually studied quite extensively by all the major automakers.

Every time, the final decision came to "no" for much the same reasons that brakes are not brake by wire --- too risky.

The closest we came in steer by wire is the current electric assist to replace the hydraulic assist.

When you are dealing with millions of units and with potential liability involving them easily $3m per unit failed X failure rate and cost to retrofit / recall, the dynamics of the industry call for innovation in mostly low risk places... or at least.. perceived low risk... like the electronic ignition key.

I am watching carefully how the rear camera system vs. regular mirrors is working out.

My bet - we will not see a mirrorless car in 20 years. There may be only 1 mirror, and it may be tiny, but there will be one.

 

[jmw]

I hated the rear view camera approach on an Audi I drove. It messed up all my perception of position and distances and, being in the lower centre console, was awkward to view and gave a restricted view.
Using the mirror I can move my head side to side to get a wider view. Moving my head side to side to see stuff not in the camera's view made me look like an idiot - and you don't get a joystick to wiggle the camera probably because that would be just one more distraction.

JMW

http://www.ViscoAnalyser.com

 

[patprimmer]

Actually my money is on camera and LCD type rear mirrors within a few years. Like all things electronic, the performance will improve at an astonishing rate until images are clear and undistorted, resolution is crisp, night vision is strongly enhanced and cameras with quite small lenses will be at the front outside top edge of both front guards (fenders) and one in the middle of the rear tailgate area. The rear one will automatically look down as reverse is selected.

This will not only enhance overall rear vision to cover spots not easily covered by mirrors, but will also remove a significant amount of frontal area from a very high ir speed region of the body and will reduce overall width and remove one of the most prone to damage items from the exterior of the car.

As we will no longer need to adjust the mirror to accurately reflect the image to our eyes, the coverage will remain constant to whoever is driving and not require adjustment for each driver or driving position.

Al this with a relative cost saving if the cost of electronics and energy for glass making follows the trends of the last 20 years

Regards
Pat
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[jmw]

An LCD is cheaper than a mirror?

At what point do the drivers stop thinking?
Should we design cars for idiots or simply keep them off the roads?

PS, you'll need to have an in car camera to allow the ladies to use it to do their make-up and it means having to placew the display where it is convenient to use for that purpose.

OK, that's me red flagged for being sexist. Sorry ladies.

JMW

http://www.ViscoAnalyser.com

 

[jmw]

PPS You'll also need image reversal when selecting the in car view for doing the make-up.

JMW

http://www.ViscoAnalyser.com

 

[evelrod]

Sadly, I see this all electronic trend continuing as we progress further into the "nanny state" environment. Full "fly by wire" electronic controls are not only possible, but probable in the very near future. A guess on my part, maybe ten to twenty years. That's "ten years from an engineering standpoint" and "twenty years from the political point". Seeing how the "moon project" of the late 60's went so well (really, shouldn't we have a functioning colony on the lunar surface by now?), it may take a few decades longer for really big and meaningful changes to be implemented. It will happen, despite our "best" efforts. Not the changes I'm in favor of...then again, I'm obviously too old to understand.

Rod

 

[Lou Scannon]

I hear ya Rod, I'm nostalgic not for everything in my old days & even beforehand that was different from nowadays but for many things; and most of the "progress" I foresee I can do without... grump grump grump...

I forgot what I was going to say

 

[Gearloose1]

"PS, you'll need to have an in car camera to allow the ladies to use it to do their make-up and it means having to placew the display where it is convenient to use for that purpose. "


That can be done with an LCD that is programmed to display a pic of same person circa 17 or 18, with motion sensors detecting her motions and expressions and replicating it on the screen with a synthesized avatar like likeness.

It will be an incredibly popular option for $15,000 in today's dollars when it is available.

 

[patprimmer]

Many cars have a vanity mirror that is separate to the rear view mirror.

An electronic failure in a mirror does not cause a life threatening situation. It is a lot easier step than a steer by wire system from a litigation point of view.

It also eliminates a blind spot where the existing mirrors are mounted.

What did a laptop computer cost 10 or 20 or even 5 years ago.

They where a months salary or more, now they can be less than one days salary.

Regards
Pat
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[NormPeterson]

Electronic involvement is a very good solution for things that need continuous monitoring and adjustment, such as with the engine's control system.

What I'm not sure I agree with is the trend (mandated or otherwise) toward making cars "smarter" in order to compensate for drivers who are dumber or who allow themselves to become more distracted.

I'm more concerned that with electronic everything it becomes possible to develop and produce a vehicle that might inherently be of only marginal stability, with the level of stability required for public consumption provided electronically. It might only require something as simple as an inop ABS wheel sensor to potentially put a driver who has had no opportunity to experience other than linear behavior, in over his head when it all goes offline. Wasn't there a recent Lexus SUV J-turn tipping issue that got solved electronically? 40 years ago, it'd have been the carbon-based brains that got "reflashed" and some useful general human knowledge would have come out of it.


Pat - you have to pick your times and places for keeping your driving practice "current", although you don't have to get deep into "arrest me, officer" territory to keep your skills a step or two ahead of most other drivers.

I rarely use cruise control, as by doing so neither foot can be all that near the pedals that they would need to be near should the traffic situation suddenly deteriorate, and when fumbling around to get on the right side of said pedals could be disastrous. I doubt that I could even stand being essentially a passenger with a steering wheel to hang onto for more than a few minutes at a time, and I suspect that there would be times where I'd be at risk of falling asleep.


Norm