Auto or manual

Kenai said:
Out of interest, if it did only continue to apply the brakes after a braking action, what would you call the function?
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Probably just a 'latch' or a 'catch', possibly a detent.
As you describe it in the quote above, it's essentially no different to a retractable Biro™ or a door latch. You wouldn't call that an automatic mechanism, would you?

Kenai said:
'manual hold' doesn't really sound right for a system that continues to apply the brakes after you release the brake pedal :p
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Could just call it the brake-hold or brake-detent.

TBH, I think in this instance calling it "automatic" is more for marketing purposes than being technically correct... like how people 'literally' misuse the term "literally".
Automatic things are generally perceived to do something, like an auto-pilot. They don't automatically sit there doing nothing.

Saying that, there are plenty of other things that continue to hold something in place after you let go, though none of which are considered (or called) automatic. Tools like squeeze-clamps, for example.
 
ttaskmaster said:
Could just call it the brake-hold or brake-detent.
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If I have my foot on the foot brake and release the brake, the car continues to hold pressure in the brake lines until I apply the throttle. This is, in my vehicle at least, called 'hill start assist' and is not 'automatic' anything. This is also not the system I am talking about.


TBH, I think in this instance calling it "automatic" is more for marketing purposes than being technically correct... like how people 'literally' misuse the term "literally".
Automatic things are generally perceived to do something, l
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Which Auto Hold does. Let me talk you through exactly what my car does with the auto hold system enabled.

If the car comes to a halt, the car will automatically apply the parking brake - not hold the brake lines, not 'latch' anything, but automatically operate the parking brake actuator mechanism without me specifically requesting it to. The car itself performs this action when certain parameters are met, such as vehicle speed 0mph after previously being greater than 0mph.

If I switch the auto hold system off, then the handbrake is only applied when I physically pull the handbrake switch in the cabin.

The fact we're still going round and round with this is getting ridiculous.
 
I recently went from a VW Passat 2.0 TDI 170 manual to a F11 535D. I find the fact I don't need to change gears anymore amazing, always has the right gear and the changes are super smooth. Paddles I'm not sold on. I thought I'd possibly use them but the gearbox in sport mode is plenty good enough. I'll never go back to a manual again.
 
[TW]Fox said:
If I switch the auto hold system off, then the handbrake is only applied when I physically pull the handbrake switch in the cabin.
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maybe already mentioned, but your comment begs the definition.
- a mechanism that replaces some action a human would otherwise have to perform is automatic
 
[TW]Fox said:
If I have my foot on the foot brake and release the brake, the car continues to hold pressure in the brake lines until I apply the throttle. This is, in my vehicle at least, called 'hill start assist' and is not 'automatic' anything. This is also not the system I am talking about.




Which Auto Hold does. Let me talk you through exactly what my car does with the auto hold system enabled.

If the car comes to a halt, the car will automatically apply the parking brake - not hold the brake lines, not 'latch' anything, but automatically operate the parking brake actuator mechanism without me specifically requesting it to. The car itself performs this action when certain parameters are met, such as vehicle speed 0mph after previously being greater than 0mph.

If I switch the auto hold system off, then the handbrake is only applied when I physically pull the handbrake switch in the cabin.

The fact we're still going round and round with this is getting ridiculous.
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Weird, what you call hill start assist (why would you need this in an automatic car?) is now called Auto Hold, which thankfully doesn't apply the handbrake (why would you do that?) at all until you put the car in Park and turn it off.
 
Clarkey said:
Weird, what you call hill start assist (why would you need this in an automatic car?)
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Because even a ZF8HP will allow slight rollback on a steep hill I guess, but I broadly agree. It's very useful in a manual but I didn't even notice I had it in the 5 Series until I was trying to reverse down hill once.
 
[TW]Fox said:
If I have my foot on the foot brake and release the brake, the car continues to hold pressure in the brake lines until I apply the throttle. This is, in my vehicle at least, called 'hill start assist' and is not 'automatic' anything. This is also not the system I am talking about.
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So there already is a plausible term for such a system... although arguably a misnomer as it would presumably be intended for use in situations other than just hill starts...

[TW]Fox said:
Which Auto Hold does.
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Maybe, but that's no longer what we were discussing. Kenai specifically detailed a different setup, to which I responded with what you just quoted.
 
auto hold and hill hold assist arent the same technically
well according to audi anyway

Mine lists both

i think this gets to the crux

"Some vehicles may have both Hill-Hold and Hill-Start Assist, while the principal is the same, a hill-start assist function is usually only intended to prevent your vehicle from rolling backwards as you transition from the brake to the throttle. An Auto-Hold function is intended to hold the vehicle in place until the throttle is pressed which could be several minutes or more."
 
ttaskmaster said:
It's literally called a 'radiator', but it doesn't actually 'radiate' anything. It convects.
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It literally radiates heat, that's how it works. This radiated heat then rises and forms a convection current in the room/space/whatever which then heats the room. The radiator still heats the surrounding air by radiating. So it has a very literal, and correct, name.


Anyway, back on topic. My Focus has hill-start assist only. That is, if it detects I'm on enough of an incline it'll hold the brakes on for a few seconds after I release the brake pedal to ensure I don't rollback. It's a torque convertor automatic, so in most cases it'd start creeping but the creep isn't strong enough when on anything more than a moderate incline so it's a nice feature to have.

I'd be interested to know how the car would handle an automatic handbrake (and associated auto-hold feature). Because, for the car's stop/start to work, I have to be in gear and with the brake pedal held hard enough. Once I'm ready to start moving off, lifting the brake pedal slightly triggers the engine to start, and then of course the creep kicks in straight away. If my car were to have auto-hold (ie. auto handbrake at stops), how would lifting off the brake pedal react then? I guess the car would know it's just activated auto-hold, and therefore wouldn't start the engine until I hit the throttle again? At which point the engine would restart and then auto-hold (handbrake) would disengage?
 
Ah but Fox has been saying that his auto hold will hold until the throttle is hit again. And it holds by applying the electronic handbrake. On mine it only activates for a few seconds. If I don’t touch the throttle the brakes still self-release after those few seconds are passed, which would let the car roll backwards.

Manufacturers seem to be using the term a little interchangeably which must be adding to the confusion but the two technologies seem different, so should have separate names.
 
Hill assist (line pressure) vs auto hold ( handbrake)

My M3 has hill assist as its a DCT but it also has a manual handbrake. Hill assist will hold the car long enough for the engine to restart and start accelerating
 
squerble said:
It literally radiates heat, that's how it works. This radiated heat then rises and forms a convection current in the room/space/whatever which then heats the room. The radiator still heats the surrounding air by radiating. So it has a very literal, and correct, name.
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Actual radiated heat is a very small percentage of the total heat output, otherwise you'd not be able to mount them so close to wall without burning your wallpaper.
Also, heat does not rise.
 
ttaskmaster said:
Actual radiated heat is a very small percentage of the total heat output, otherwise you'd not be able to mount them so close to wall without burning your wallpaper.
Also, heat does not rise.
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Hot air is less dense that's why it rises:confused:. They radiate heat then convect it around the room. Also vacuums do create a vacuum (that's how they work).
 
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