AutoBrake Connection: Connecting Motion Sensor to Brake Line

[Mike Bettua]

When is the motion sensor being connected to the brake line of the automobile?

 

[SteamKing]

What motion sensor? I'm afraid being terse and cryptic is not helping.

 

[xxChrisxx]

What motion sensor? I'm afraid being terse and cryptic is not helping.

I assume he means city safety braking systems provides braking assistance or even brakes for you. Typically a laser at the front.

It has some sort of accumulator and actuator on the hydraulic circuit.

 

[Mike Bettua]

Would you or wouldn't you recommend mandating that on all vehicles like the third brake light has been?

 

[jim hardy]

NO !

I won't tolerate a machine that presumes to think for me.

I'm fed up with being forced to buy and maintain junk i neither need nor want.

 

[xxChrisxx]

NO !
I won't tolerate a machine that presumes to think for me.
I'm fed up with being forced to buy and maintain junk i neither need nor want.

Can't stop the march of technology.

The rule of thumb is if you want to know what safety technology will be on your car in 10 years, look at the Mercedes S class today.

Assisted braking and collision detection is a perfectly logical evolution of safety systems. In many instances of emergency braking people don't apply enough force, or simply forget to steer out of the way.

In 10 years we'll all be saying how marvellous the new safety systems are. The same way that airbags, ABS and stability control are seen as essential safety aids today.

 

[jim hardy]

The same way that airbags, ABS and stability control are seen as essential safety aids today.

Exactly why i keep my 1968 Ford.

 

[xxChrisxx]

Luddite ;)

Late 60s. Isn't that after the introduction of the collapsible steering column? You must be some sort of safety hippy. Real men don't mind speared through the chest when they crash.

 

[jack action]

The same way that airbags, ABS and stability control are seen as essential safety aids today.

Exactly why I keep my 1969 Chevrolet.

Can't stop the march of technology.

Fatalist ;)

 

[jim hardy]

If you're a poor driver you might get some good from ABS.
Or it might kill you.
Statisticaly it's of no benefit.




NHTSA :
http://www.nhtsa.gov/cars/rules/regrev/evaluate/808206.html

All types of run-off-road crashes - rollovers, side impacts with fixed objects and frontal impacts with fixed objects - increased significantly with ABS. Nonfatal run-off-road crashes increased by an estimated 19 percent, and fatal crashes by 28 percent.

Rollovers and side impacts with fixed objects - crashes that typically follow a complete loss of directional control - had the highest increases with ABS. Nonfatal crashes increased by 28 percent, and fatal crashes by 40 percent.

Frontal impacts with fixed objects, where the driver is more likely to have retained at least some directional control prior to impact, increased by about 15-20 percent, both nonfatal and fatal.

The negative effects of ABS on run-off-road crashes were about the same under wet and dry road conditions.

The reason for these negative effects is unknown. One possibility is that average drivers may at times steer improperly in panic situations. Because ABS preserves steering control under hard braking, cars may be swerving or heading off the road.

The observed effects of ABS on snowy or icy roads, while not statistically significant, were all similar to the effects on wet roads - i.e., positive for multivehicle collisions, negative for run-off-road crashes.

The overall, net effect of ABS on police-reported crashes (including multivehicle, pedestrian and run-off-road crashes) was close to zero.

The overall, net effect of ABS on fatal crashes was close to zero.

 

[jim hardy]

Luddite ;)

Dandy ;)

 

[Damo ET]

If you're a poor driver you might get some good from ABS.
Or it might kill you.
Statisticaly it's of no benefit.




NHTSA :
http://www.nhtsa.gov/cars/rules/regrev/evaluate/808206.html

You can't be serious! That paper is from 1994.

Something a little more up to date.
http://en.wikipedia.org/wiki/Anti-lock_braking_system

Damo

 

[jack action]

You can't be serious! That paper is from 1994.

Something a little more up to date.
http://en.wikipedia.org/wiki/Anti-lock_braking_system

You can't be serious!

The sections titled 'Effectiveness' and 'Regulations' from your source basically confirm the findings of the 1994 study previously mentioned.

 

[edward]

If you're a poor driver you might get some good from ABS.
Or it might kill you.
Statisticaly it's of no benefit.




NHTSA :
http://www.nhtsa.gov/cars/rules/regrev/evaluate/808206.html

I think that it is of less benefit than it could be. It is statistically of no benefit because many people do not realized that with ABS they can still steer clear of a collision with the brakes fully engaged. A lot of people became wary of ABS in the early years and rightfully so. The 1990's vehicles seemed to be a trial and error period.

http://www-nrd.nhtsa.dot.gov/Pubs/811182.pdf

I have a 1972 International Harvester 1/2 ton truck. It has no power steering, no power brakes and no A/C. Ironically International had ABS as an option even way back then. I thought it was an expensive toy and opted out.

ABS on the rear wheels of trucks is essential for safety. A truck with no load in the bed is especially prone to skidding.

 

[xxChrisxx]

Most crashes occur in urban areas (particularly at junctions), and motorways have Armco barriers so going off road isn't as much of an issue. It's the reason the EU have made ABS mandatory on all cars.

The main problem with ABS is that people panic and forget to steer. I've seen it of several occasions, a clear escape path to the side, someone under ABS just plows straight into the back of the car infront.

Modern 4 channel systems are so good now that they are very close to threshold braking. You can feel the car squirming as it pluses the wheels in succession.

 

[Mike Bettua]

Wouldn't it prevent accidents in situations where the driver fell asleep at the wheel?

 

[jim hardy]

How much automation is too much? Aviation industry is struggling with that now.


I expect the brakes to do what i command them. If i want all four wheels locked i expect the brake calipers to obey my right foot.

I would welcome a switch that allows me to engage an electronic gizmo that'll apply brake to whichever drive wheel loses traction. Have more than once contemplated two separate parking brake handles..

"Newer" and "Better" are not synonyms.
That Mercedes Benz marketing men can create in some people a desire for fancy doodads does not create in me an obligation to spend three years' salary for one. Let alone maintain that silly stuff.
I drive two-thousand dollar cars because they last me half as long as forty thousand dollar cars.
I took my '92 Oldsmobile out on the ice last winter to familiarize myself with how its ABS behaves. I wasn't impressed, it pushes the front from side to side as if attempting to steer . When the ABS dies of old age i will remove it.

I used to repair computers as part of my job; see my signature. I simply will not own an automobile with a computer in control of throttle butterfly plate , brakes or power steering.

However - being a controls guy I doappreciate the benefit of closed loop fuel mixture control, so long as it fails to a "Limp Home" mode and provides a diagnostic message.

old jim

 

[cjl]

I took my '92 Oldsmobile out on the ice last winter to familiarize myself with how its ABS behaves. I wasn't impressed, it pushes the front from side to side as if attempting to steer . When the ABS dies of old age i will remove it.

Judging modern ABS behavior on the basis of a '92 Oldsmobile is not really giving it a fair chance - the modern systems behave dramatically different, and I would never want to drive on a slick surface without modern ABS. Can it be done? Sure, but the additional control under braking is really nice to have when descending a long icy hill at 30 or 40 miles per hour. I also like ABS in my fun car, since I appreciate the protection against flat spotting the tires when I take it to the track. The automated braking on the other hand is too much, in my opinion.

 

[xxChrisxx]

I like the idea of preprimed brakes that allow maximum deceleration even if you only use minimal pedal effort.

Fully auto braking is slightly more dubious, especially with pedestrian recognition. How long til the kids figure out you can jump into the road and then jump back and cause the car to emergency brake... fun times.

 

[edward]

NO !

I won't tolerate a machine that presumes to think for me.

I'm fed up with being forced to buy and maintain junk i neither need nor want.

But Jim the electronic stability control systems have multiple sensors that can decide what you want.

The ESC system uses several sensors to determine what the driver wants (input). Other sensors indicate the actual state of the vehicle (response). The control algorithm compares driver input to vehicle response and decides, when necessary, to apply brakes and/or reduce throttle by the amounts calculated through the state space (set of equations used to model the dynamics of the vehicle.

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

I have to admit that I was impressed when I took a new Infinity out for a test drive. I did a quick double lane change while going through a curve and it was flawless.

A lot of accidents happen when people lose control or run off of the road in a curve and ESC really helps with that. On the other hand will drivers come to rely on the systems when they do dumb things like making a double lane change in a curve? What happens if there is a flaw in just one sensor?

I am old school myself and I just don't trust that many sensors on a vehicle.

 

[cjl]

What happens if there is a flaw in just one sensor?

Generally, the vehicle can detect the anomalous sensor data, and respond in one of several ways. If the sensor is redundant, it can ignore the sensor. If the sensor is not redundant, the vehicle can continue to operate in a degraded mode where at worst, it simply behaves as it would have with no electronic stability control.

 

[jim hardy]

Judging modern ABS behavior on the basis of a '92 Oldsmobile is not really giving it a fair chance

I guess you do have a point, it's an older car now.
Funny how as we get old time compresses - I've had that Oldsmobile for fourteen years now and it's still my new "Sunday-Go-To-Meeting" car.
Last of the rear drive nineteen foot-long stationwagons with that Pullman car ride. Only thing i'd trade it for would be a Model A Ford with hydraulic brake upgrade, to the end of achieving ultimate simplicity.
"No check engine light, no metric bolts, No Problem! "

old jim

 

[xxChrisxx]

I enjoy old cars, they so have a soul and personality, and mood swings. But they simply can't compare to modern machinery for getting a task done. For all the talk of simplicity, new cars are simply more robust.

Modern unreliability means you arrive at your destination annoyed because there is a yellow light on your dashboard.

Old school unreliability means you don't arrive at all.

Cars are cars, modern equipment is fundamentally no different to old stuff if you follow simple rules of keeping the engine watered, oiled and clean and electrics free from moisture.

 

[edward]

I guess you do have a point, it's an older car now.
Funny how as we get old time compresses - I've had that Oldsmobile for fourteen years now and it's still my new "Sunday-Go-To-Meeting" car.
Last of the rear drive nineteen foot-long stationwagons with that Pullman car ride. Only thing i'd trade it for would be a Model A Ford with hydraulic brake upgrade, to the end of achieving ultimate simplicity.
"No check engine light, no metric bolts, No Problem! "

old jim

I had an old 1936 ford with mechanical brakes when I was in high school. Come to think of it they were anti lock brakes, and also anti stop, at times. Keeping the cables lubed and everything adjusted was essential.

Even the hydraulic brakes had to be adjusted. We went a long time with no major change In brakes until the self adjusting brakes came along in the 1960's.

I wonder what lies in the future. The New Honda Accord hybrids use a fly by wire electric servos to apply the brakes.

What makes this even more impressive is the fact that Honda is using brake-by-wire technology where electro servos apply pressure to the calipers instead of brake fluid fed through hydraulics. The Accord does have a master cylinder feeding fluid to brake lines, but they end at electric transmitters that send a signal to the electric servos.

http://www.autoguide.com/manufacturer/honda/2014-honda-accord-hybrid-review-3522.html

 

[jack action]

Modern unreliability means you arrive at your destination annoyed because there is a yellow light on your dashboard.

There must be fairies and unicorns in the world you live in. You should read the news about GM, Toyota, http://blog.caranddriver.com/honda-taking-heat-for-hiding-deaths-injuries-from-exploding-airbag-recalls/, Hyundai and Volkswagen, to name a few.

Old school unreliability means you don't arrive at all.

Cars are cars, modern equipment is fundamentally no different to old stuff if you follow simple rules of keeping the engine watered, oiled and clean and electrics free from moisture.

A well maintained car from the 50's is just as reliable as one from today (Everybody relied on their cars to go to work back then and the ones who arrived weren't consider the «lucky ones»). But routine maintenance had to be done more often and if it wasn't done, the car was unreliable, just like today's car. The difference between old and modern cars is that the simplicity of old cars made them cheaper to buy, but demand more maintenance and they were not as idiot-proof as modern cars (for example, a carburetor is easy to flood if you keep pushing the gas pedal with the ignition off). The problem with the complexity of modern cars is that once their maintenance-free period is over, they're only good for the scrap yard as they become too expensive to repair.

I prefer to see this as different philosophies rather than one better the other. IMHO, the only true improvements that have been done in cars are in the materials (tires, lubricants, etc.). So I agree with you, cars are cars.

 

[jim hardy]

Old school unreliability means you don't arrive at all.

No, it means you might arrive with greasy hands from a simple roadside repair.
Modern reliability means Onstar calls the tow truck for you.

Jack is right it's a philosophy thing - some of us secondhand lions refuse to accept we're helpless.

 

[Mike Bettua]

Chevy or Tesla?

Regarding ("Ford"/"General Motors") (and/or) ("Tesla Motors") why do you prefer the one that you prefer?

 

[jim hardy]

Regarding ("Ford"/"General Motors") (and/or) ("Tesla Motors") why do you prefer the one that you prefer?

I won't buy any foreign car because i have yet to find a decent shop manual for one. My Toyota service manual was a disaster , so never again.

You just can't beat the US Big 3 factory issued manuals. Particularly with today's plethora of sensors and interactive systems.

 

[jim hardy]

Regarding ("Ford"/"General Motors") (and/or) ("Tesla Motors") why do you prefer the one that you prefer?

forgot to mention - i like Chryslers from the early 90's because you don't need a code reader. And they're considerably simpler than today's extravaganzas.
You switch ignition off to on four times, leaving it on. The ECU sends you the trouble codes on "check engine" light, and on the electronic odometer if it has one. Look 'em up on the internet and you've saved a trip to the shop.
That procedure located a defective thermostat, oxygen sensor, egr solenoid and throttle position sensor on a friend's 'handyman special' 95 Dodge Minivan . Fixing them improved it from 17 to 24 mpg highway. And it extinguished the 'check engine' light.

On GM's you can do the same thing but it requires crawling under the dash to insert a paperclip into an obscure plug.

Post '96 you can use the el-cheapo $40 reader from Sears, or have the guys at an auto parts store read them for you with their loaner. Probably on foreign cars too.

 

[edward]

In the past few years new uses have come along for the onboard diagnostics port. First there was a device that plugged into the port so people could monitor their teenager's driving habits.

It has gone a step further now and insurance companies want people to use a device that let's them check on you.

I was just offered such a deal from Hartford. Just plug the widget into the OBDII and a private company will uses cell phone equipment to monitor; my speed, acceleration rate, miles driven, and g forces continuously.

The one that didn't make any sense was the GPS monitoring? Do they really need to know where I am at all times?? Especially since the GPS monitoring did not provide any kind of theft protection. It was like Lojack without the Lojack.

They did mention that all of my driving data will be stored in a computer in another country.

For all of this I may or may not receive a 5% to 15% premium savings. It took about 20 minutes to read the disclaimer. The deal breaker for me was that they may sell my information to anyone.

If I failed to return the widget when ask for it I had to pay $100. What if someone reaches in the window when I am stashing groceries in the truck and steals the thing?

I have a feeling that this will soon be mandatory.

http://allthingsnav.navigation.com/article/mining-data-port-ii-look-usage-based-insurance-programs