USAF feels Oleg's pain

[julian265]

Originally Posted by Azimech

Can you believe carmakers wish to delete the physical connections between steer-wheels and pedal-brakes? I'm no luddite, but this goes too far.

+1 to that. Hydraulic brakes are so simple and reliable... Perhaps a good reason to change it is if you have a completely automated braking system, but my experiences of ABS have been poor, with it degrading braking on surfaces other than smooth bitumen roads. I'll never forget the ~2003 camry that chattered it's way into an (empty) intersection, after we started braking side-by-side coming down a wet road on a slight hill. My '83 car stopped without issue. Traction control is another story of mis-automation. Try a gravel road/driveway on a moderate incline and it struggles.

Originally Posted by WTE_Galway

Unfortunately programmers as a profession are not subject to the industry self regulation and/or government certification that governs the conduct of architects, engineers, lawyers, doctors, surveyors, accountants and other professions.

The software industry is more akin to book or music publishing then any of the more traditional "professions" .

The law makers might actually have to understand the programming process to try to regulate it... Or the government will outsource the writing of the regulations YET AGAIN and force people to PAY to find out what they are required to do.

Regulations are an interesting topic, I think what prevents a lot of mistakes within engineering are the numbers of people that check the designs, which is often the exact opposite with programming. I don't see a reason to impose regulations on non-safety critical programmers though.

[swiss]

Originally Posted by julian265

+1 to that. Hydraulic brakes are so simple and reliable... Perhaps a good reason to change it is if you have a completely automated braking system, but my experiences of ABS have been poor, with it degrading braking on surfaces other than smooth bitumen roads. I'll never forget the ~2003 camry that chattered it's way into an (empty) intersection, after we started braking side-by-side coming down a wet road on a slight hill. My '83 car stopped without issue. Traction control is another story of mis-automation. Try a gravel road/driveway on a moderate incline and it struggles.

Well, actually ABS decreases braking distance - on any surface other than on dry tarmac.

I remember following experiment, which involved braking in snow, with and without ABS, with and without winter tires.

ABS vs conventional, winter tires:
ABS<conventional

ABS vs conventional, summer tires:
Conventional<ABS

The latter is explained by the conventional wheel locking up, building a wedge of snow in front of the tires which increases friction.
The ABS however is confused, because then summer tires can't get any grip on the snow - and the ABS doesn't want to let them slip, as result the brake stays open...

Is it possible your camry had shitty tires?

[Azimech]

Who knows... it wasn't his Camry.

But anyway, the argument wasn't against ABS, which can be switched off (in the models I drive in, 1 circuit breaker) but the total absence of a hydraulic/mechanical linkage to the pereiopodical appendage (leg). Even a hydraulic system with a leak or a faulty brake vacuum pump will stop your car but if you are pushing the pedal linked to a rheostat while you've lost complete electrical power, maybe smashing your windscreen and blowing in the wind might help (choose your context).

[swiss]

Originally Posted by Azimech

Who knows... it wasn't his Camry.

But anyway, the argument wasn't against ABS, which can be switched off (in the models I drive in, 1 circuit breaker) but the total absence of a hydraulic/mechanical linkage to the pereiopodical appendage (leg). Even a hydraulic system with a leak or a faulty brake vacuum pump will stop your car but if you are pushing the pedal linked to a rheostat while you've lost complete electrical power, maybe smashing your windscreen and blowing in the wind might help (choose your context).

I'm your side here.
But they could design it like pneumatic truckbrakes where your need the air pressure(in our case epower) to keep the brakes open - if their system leaks air, the truck just brakes and stops.

[Azimech]

Keep in mind the pneumatic brake system of a truck is very complex and redundant, with two pressure gauges which a driver is trained to check and act upon. All (competent and awake) drivers will stop the truck before the brakes kick in, at a safe location with opportunity to warn the traffic behind him. I had to learn this stuff.

If a car loses all power and starts braking, it could be at an unsafe spot, without emergency and brake lights. That could lead to utter disaster, especially on a dark, wet road (in a corner, on a downwards slope, etc.)

Even if the system has some kind of a capacitor and warns the driver before the brakes kick in, a lot of people ignore warning lights, interpret them wrong or simply have no clue what it means. My mother is notorious. If I didn't fill up her engine oil every now and then, she called me with the message that a combination of four lights (yes, the Citroën BX does that) came on during corners. Zero oil pressure. I've explained to her a dozen times what it means, that the manual is in the glove compartment, the oil in the trunk and how to fill up the engine. She just doesn't want to remember I guess. Finally I gave up and just bought her a different BX that doesn't use oil at all.

[swiss]

Originally Posted by Azimech

Keep in mind the pneumatic brake system of a truck is very complex and redundant, with two pressure gauges which a driver is trained to check and act upon. All (competent and awake) drivers will stop the truck before the brakes kick in, at a safe location with opportunity to warn the traffic behind him. I had to learn this stuff.

If a car loses all power and starts braking, it could be at an unsafe spot, without emergency and brake lights. That could lead to utter disaster, especially on a dark, wet road (in a corner, on a downwards slope, etc.)

Sure, but have to have a plan. What is it?

[Azimech]

Could you redefine your question please?

[julian265]

Originally Posted by swiss

Well, actually ABS decreases braking distance - on any surface other than on dry tarmac.

I remember following experiment, which involved braking in snow, with and without ABS, with and without winter tires.

ABS vs conventional, winter tires:
ABS<conventional

ABS vs conventional, summer tires:
Conventional<ABS

The latter is explained by the conventional wheel locking up, building a wedge of snow in front of the tires which increases friction.
The ABS however is confused, because then summer tires can't get any grip on the snow - and the ABS doesn't want to let them slip, as result the brake stays open...

Is it possible your camry had shitty tires?

It wasn't mine, I was driving next to it. It was ~3 years old at the time.

I don't claim to know about ABS and snow... I don't drive through any - but my mate's cars with ABS have each become (a little dangerously) confused on loose dirt roads, which we frequent. Hence as Azimech mentioned, they take out the ABS fuse, and regain predictable brakes.