1 2 3 4
GameboyRMH
GameboyRMH GRM+ Memberand PowerDork
10/22/12 8:38 a.m.

Yeah a lot of newer cars have electrically-actuated handbrakes, they're a maintenance nightmare.

Curmudgeon
Curmudgeon MegaDork
10/22/12 9:31 a.m.
GameboyRMH wrote: Yeah a lot of newer cars have electrically-actuated handbrakes, they're a maintenance nightmare.

First time I saw that in a KIA ad, my knee jerk reaction: are we really that damn lazy as a people?

Javelin
Javelin GRM+ Memberand MegaDork
10/22/12 9:40 a.m.
Jay wrote: When was the last time your blender/fridge/home theater system was brought down by a "computer glitch"?

About two days ago.

yamaha
yamaha Dork
10/22/12 9:44 a.m.

Just remember how well just the electric power assist went in GM vehicles.....

Curmudgeon
Curmudgeon MegaDork
10/22/12 9:54 a.m.

Magnasteer was actually pretty cool. It was glitchy as hell, though. Its glitchiness was an inconvenience, rather than life threatening and it had the mechanical system as a backup.

Max_Archer
Max_Archer Reader
10/22/12 3:40 p.m.

The cool thing about steer-by-wire, in my mind, would be the ability to customize steering ratios at will. Imagine being able to set the car to formula-style steering for the AutoX course. Put a force-feedback unit like those in high-end sim racing steering wheel setups and you could have tons of feedback, and set it so that you'd only have it when you wanted it, too.

Flight Service
Flight Service UltraDork
10/22/12 5:23 p.m.
Max_Archer wrote: The cool thing about steer-by-wire, in my mind, would be the ability to customize steering ratios at will. Imagine being able to set the car to formula-style steering for the AutoX course. Put a force-feedback unit like those in high-end sim racing steering wheel setups and you could have tons of feedback, and set it so that you'd only have it when you wanted it, too.

That's what we did at Clemson with our units. Modularized production for LHD and RHD, adjustable ratios for preference and for safety.

Osterkraut
Osterkraut UltraDork
10/22/12 8:22 p.m.
Strizzo wrote: In reply to Osterkraut: We do, in fact have cable actuated brakes as a backup to hydraulic brakes. That's why it's called the emergency brake.

As previously mentioned, any attempt to use the parking brake to bring a car down from speed would result in a situation quite like the loss of steering control...

Flight Service
Flight Service UltraDork
10/22/12 10:27 p.m.

In reply to Osterkraut:

If you yank it like an idiot...nevermind.

nocones
nocones GRM+ Memberand Dork
10/22/12 10:43 p.m.

My wifes outback has the electronic parking brake. It won't engage above ~2 mph. I'm not really sure what would happen if the brakes failed. Probably would get to try out all those airbags. It is a manual trans so there is always downshifting.

sobe_death
sobe_death Reader
10/23/12 4:46 a.m.
nocones wrote: My wifes outback has the electronic parking brake. It won't engage above ~2 mph. I'm not really sure what would happen if the brakes failed. Probably would get to try out all those airbags. It is a manual trans so there is always downshifting.

They will activate, you just have to have your foot on the brake pedal already. Doesn't help if you're trying to hoon it, but it does help if you're in an emergency situation.

GameboyRMH
GameboyRMH GRM+ Memberand PowerDork
10/23/12 7:57 a.m.
Osterkraut wrote:
Strizzo wrote: In reply to Osterkraut: We do, in fact have cable actuated brakes as a backup to hydraulic brakes. That's why it's called the emergency brake.
As previously mentioned, any attempt to use the parking brake to bring a car down from speed would result in a situation quite like the loss of steering control...

I've driven cars with only a parking brake, but you have to drive them like a big rig and be especially vigilant for people slamming on the brakes in front of you for no apparent reason. 100-0 takes nearly 1/8 mile with only the parking brake in a Samurai.

Wally
Wally GRM+ Memberand UltimaDork
10/23/12 9:47 a.m.
GameboyRMH wrote: As previously mentioned, any attempt to use the parking brake to bring a car down from speed would result in a situation quite like the loss of steering control...

I've driven cars with only a parking brake, but you have to drive them like a big rig and be especially vigilant for people slamming on the brakes in front of you for no apparent reason. 100-0 takes nearly 1/8 mile with only the parking brake in a Samurai.

I would think 0-100 in a Samurai would take longer than that

Mitch Hedberg said: I rent a lot of cars, but I don't always know everything about them. So a lot of times, I drive for like ten miles with the emergency brake on. That doesn't say a lot for me, but it really doesn't say a lot for the emergency brake. It's really not an emergency brake, it's an emergency "make the car smell funny" lever.
GameboyRMH
GameboyRMH GRM+ Memberand PowerDork
10/23/12 9:55 a.m.
Wally wrote: I would think 0-100 in a Samurai would take longer than that

Oh it sure does. If you put low-profile tires on one, it takes about 1/3 mile. If you have any kind of offroad tires on it or you're driving into a headwind, it takes infinity miles.

Osterkraut
Osterkraut UltraDork
10/23/12 10:16 a.m.
Flight Service wrote: In reply to Osterkraut: If you yank it like an idiot...nevermind.

Here's the situation: You're cruising along, 55mph. Suddenly, your brake line ruptures* as you apply the brakes to stop before hitting the car an acceptable distance in front of you, which is coming to a stop. Do you?

A) Gently apply the parking brake, reaching full lock about the time your knees enter the back seat of the other car.
or
B) Rapidly apply the parking brake, potentially locking up the rear wheels and you go spinning off somewhere.

Lose/lose.

I will change my original statement to: the parking brake is an ineffective safety system for a variety of reasons, including a potential for a loss of control very similar to the loss of steering.

*Yes I realize brake systems are dual channel, but in GRM land anything not directly connected can't have redundancies., apparently.

Beer Baron
Beer Baron PowerDork
10/23/12 12:07 p.m.

I'm not so afraid of this as all you guys are. I just want to know... why? What advantage does this offer over a mechanical linkage? High performance airplanes need to be able to make micro corrections faster than humans are possibly capable of. We have yet to advance the capabilities of cars to outdo the limitations of human performance. What gain does this make?

I mean, maybe you could make an awesome racecar where you intentionally set up the handling to be so darty that a human can't keep it from spinning on their own, and this would be a way to allow super-agile handling. Clearly, that is not what it's being purposed for.

So... why?

yamaha
yamaha Dork
10/23/12 12:29 p.m.

its just a disaster waiting to happen without a mechanical linkage. I'd adopt this idea if they give me an ejection seat in the car.

Curmudgeon
Curmudgeon MegaDork
10/23/12 12:39 p.m.

The Stealth bomber won't fly without a computer making the constant microadjustments needed.

http://en.wikipedia.org/wiki/Northrop_Grumman_B-2_Spirit

In order to address the inherent flight instability of a flying wing aircraft, the B-2 uses a complex quadruplex computer-controlled fly-by-wire flight control system, that can automatically manipulate flight surfaces and settings without direct pilot inputs in order to maintain aircraft stability.[79] The flight computer receives information on external conditions such as the aircraft's current air speed and angle of attack via pitot-static sensing plates, as opposed to traditional pitot tubes which would negatively affect the aircraft's stealth capabilities.[80] The flight actuation system incorporates both hydaulic and electrical servoactuated components, it was designed with a high level of redundancy and fault-diagnostic capabilities.[81]

Notice 'redundancy'. They KNOW something will barf at some point, thus they anticipate it by building in backups.

Even with all that, its only operational crash was due to a moisture problem with the fly by wire and programming.

On 23 February 2008, the B-2 Spirit of Kansas, 89-0127 crashed on the runway shortly after takeoff from Andersen Air Force Base in Guam.[105] B-2 89-0127 had been operated by the 393rd Bomb Squadron, 509th Bomb Wing, Whiteman Air Force Base, Missouri, and had logged 5,176 flight hours. It was the first crash of a B-2. The two person crew ejected safely from the aircraft and survived the crash. The aircraft was completely destroyed, a hull loss valued at US$1.4 billion.[106][107] After the accident, the Air Force took the B-2 fleet off operational status until clearing the fleet for flight status 53 days later on 15 April 2008.[108] The cause of the crash was later determined to be moisture in the aircraft's Port Transducer Units during air data calibration, which distorted the information being sent to the bomber's air data system. As a result, the flight control computers calculated an inaccurate airspeed, and a negative angle of attack, causing the aircraft to pitch upward 30 degrees during takeoff.

If Northrop Grumman and Boeing together, at a cost of a billion dollars a pop, can't make that type of thing 100% then I have not much faith in a bunch of cost cutters in a boardroom somewhere having my survival as their first concern in the dsign of steer by wire. Nope, gimme some mechanical linkage.

93EXCivic
93EXCivic MegaDork
10/23/12 12:45 p.m.

In reply to Beer Baron:

Why? Cause some damn bean counter higher up said to engineers I bet we could make cars cheaper if we do this.

Osterkraut
Osterkraut UltraDork
10/23/12 1:14 p.m.
Curmudgeon wrote: The Stealth bomber won't fly without a computer making the constant microadjustments needed. http://en.wikipedia.org/wiki/Northrop_Grumman_B-2_Spirit In order to address the inherent flight instability of a flying wing aircraft, the B-2 uses a complex quadruplex computer-controlled fly-by-wire flight control system, that can automatically manipulate flight surfaces and settings without direct pilot inputs in order to maintain aircraft stability.[79] The flight computer receives information on external conditions such as the aircraft's current air speed and angle of attack via pitot-static sensing plates, as opposed to traditional pitot tubes which would negatively affect the aircraft's stealth capabilities.[80] The flight actuation system incorporates both hydaulic and electrical servoactuated components, it was designed with a high level of redundancy and fault-diagnostic capabilities.[81] Notice 'redundancy'. They KNOW something will barf at some point, thus they anticipate it by building in backups. Even with all that, its only operational crash was due to a moisture problem with the fly by wire and programming. On 23 February 2008, the B-2 Spirit of Kansas, 89-0127 crashed on the runway shortly after takeoff from Andersen Air Force Base in Guam.[105] B-2 89-0127 had been operated by the 393rd Bomb Squadron, 509th Bomb Wing, Whiteman Air Force Base, Missouri, and had logged 5,176 flight hours. It was the first crash of a B-2. The two person crew ejected safely from the aircraft and survived the crash. The aircraft was completely destroyed, a hull loss valued at US$1.4 billion.[106][107] After the accident, the Air Force took the B-2 fleet off operational status until clearing the fleet for flight status 53 days later on 15 April 2008.[108] The cause of the crash was later determined to be moisture in the aircraft's Port Transducer Units during air data calibration, which distorted the information being sent to the bomber's air data system. As a result, the flight control computers calculated an inaccurate airspeed, and a negative angle of attack, causing the aircraft to pitch upward 30 degrees during takeoff. If Northrop Grumman and Boeing together, at a cost of a billion dollars a pop, can't make that type of thing 100% then I have not much faith in a bunch of cost cutters in a boardroom somewhere having my survival as their first concern in the dsign of steer by wire. Nope, gimme some mechanical linkage.

Or how about, if Northrop Grumman and Boeing together decide that fly-by-wire is worth the risk at the cost of a billion dollars a pop, maybe the it's good enough for a 20,000 dollar car...

The B-2 is a horrible example for your logic because without fly-by-wire it wouldn't even exist. Nor would the F-16. Or F-22. Or F-35. You show me a drive-by-wire car that's the F-22 to the F-15 in maneuverability, or the B-2 to the B-1 in RCS, and I'll be very, very for it.

Also, isn't Senna's death suspected to be from a failure of a mechanical steering device? Should we be clamoring that only tiller steered automobiles are safe?

Curmudgeon
Curmudgeon MegaDork
10/23/12 1:20 p.m.

You miss the point. A $20,000 (or even $200,000) car won't have anywhere near the same level of redundancy that a billion dollar airplane does.

You want another Pinto fuel tank memo to surface?

http://en.wikipedia.org/wiki/Ford_Pinto

According to a 1977 Mother Jones article by Mark Dowie, Ford allegedly was aware of the design flaw, refused to pay for a redesign, and decided it would be cheaper to pay off possible lawsuits. The magazine obtained a cost-benefit analysis that it said Ford had used to compare the cost of $11 repairs against the cost of settlements for deaths, injuries, and vehicle burnouts. The document became known as the Ford Pinto Memo. This document was, technically, not a memo regarding the Pinto specifically, but a general memo Ford submitted to the NHTSA in an effort to gain an exemption from safety standards; it was also primarily focused on the cost of reducing deaths from fires resulting from rollovers, rather than the rear-end collision fires that plagued the Pinto. It was nonetheless submitted in court in an effort to show the "callousness" of Ford's corporate culture.

Osterkraut
Osterkraut UltraDork
10/23/12 1:32 p.m.
Curmudgeon wrote: You miss the point. A $20,000 (or even $200,000) car won't have anywhere near the same level of redundancy that a billion dollar airplane does.

You missed the point. Even a $200,000 car is 0.02% of the value of a B-2. Do you think the B-2's systems are five thousand times better?

novaderrik
novaderrik UltraDork
10/23/12 2:07 p.m.
GameboyRMH wrote:
Osterkraut wrote:
Strizzo wrote: In reply to Osterkraut: We do, in fact have cable actuated brakes as a backup to hydraulic brakes. That's why it's called the emergency brake.
As previously mentioned, any attempt to use the parking brake to bring a car down from speed would result in a situation quite like the loss of steering control...
I've driven cars with only a parking brake, but you have to drive them like a big rig and be especially vigilant for people slamming on the brakes in front of you for no apparent reason. 100-0 takes nearly 1/8 mile with only the parking brake in a Samurai.

i drove my 66 Lincoln Continental over 20 miles to get it home after a brake line ruptured.. that was when i found out if the emergency brake worked- it did- and learned on the fly how to make a 5300 pound car come to a safe stop from highway speeds with only the e brake and the shifter... i actually got pretty good at it by the time i got it home. that car did have the dual circuit brake system that is supposed to keep half of the brakes working when a line ruptures, and i lost all of the normal brakes when the line that goes from the frame to the rear end blew out. the parking brake on that beast allowed me to drive the car somewhat normally with a bit more effort- will the new cars do that? and will the redundant backup systems on this magical new "steer by wire" setup do the same thing?

Osterkraut
Osterkraut UltraDork
10/23/12 2:23 p.m.
novaderrik wrote: and will the redundant backup systems on this magical new "steer by wire" setup do the same thing?

Oh I dunno, what's redundant mean?

yamaha
yamaha Dork
10/23/12 2:26 p.m.

In reply to Curmudgeon:

Honestly the pinto wasn't the beginning of this problem......I remember the 65-6 mustangs, the gas tank was the trunk floor......filled by a rubber neck that went to the tailight panel. Pretty much the same setup, yet nobody cared in the 60's

1 2 3 4

You'll need to log in to post.

Our Preferred Partners
YLnv0CKS0CrCykWGWnFKysTUzkqoWQhoW1Wkp8sIGZklky1zDF0HXrw6njE3v0zU