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ABS and handbrake

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Only regular brakes. Handbrakes are not intended to ever be used while the car is in motion :) Which is why it works great for racing games, because it gives instant drift, rather than stopping the car (eventually it will stop the car, but nowhere as fast as regular brakes with ABS will).

Edited by VildNinja

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On pre-everything-smart cars, hand brakes were implemented with a steel wire that pulled on a balancing lever which distributed the force to the two sides (more or less evenly). The only thing that influenced this "hard-wiring" in some way was a screw that allowed you to shift balance slightly to one or the other side. To properly adjust your brake, you would drive slowly, at 5-10km/h and gently pull the handbrake. Then you would turn the screw to the opposite side to which the car was drifting. Once it wasn't drifting (noticeably) any more, you would let it at that. That's pretty much all "control circuitry" in hand brakes, traditionally. So... no... no ABS :-) Of course, modern cars have all kind of electronic shitnick thingies, including electric hand brakes that have a little motor with a worm gear doing the "pulling". Other than the traditional "wire" type, these brakes usually only know the states "on" and "off", which makes their main use -- hill start on manual transmission -- impossible without some very complicated additional electronic trickery that prevents the car from rolling backwards. Their second most important traditional use -- bringing the car to halt in an at least somewhat controlled way in case of hydraulic failure -- also won't work any more because either the super smart computer will not let you engage the brake at all while the car is moving, or it will instantly block the wheels. That, and they freeze in winter... My old Prius had a steel-wire foot brake that works like a traditional one. But of course they couldn't help being extra smart and added a little motor on top, which will fasten the brake when the vehicle loses power (it has no other functionality!). So if one day you change your starter battery, you will face the big surprise that you can't drive your car afterwards -- for some mysterious reason it won't move. Until you discover that someone had pulled the parking brake. Grrr...

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OK! Thanks for info. If you're in, for example, gear 1 and you're driving ar approximately 30 km/h. The engine is turning at around 5000 RPM. You pull handbrake. Will the engine stall?

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Impossible to tell. There used to be a mantra "brake must be strong enough to tame engine at all times" but that's for the main brake.

The hand brake, or parking brake as it is sometimes called, is not really designed for that purpose. It's for preventing the car to roll down a hill, to do a hill start, and to serve as emergency brake if everything else fails. It's not really meant to be able to subdue the engine (although it might). Whether or not the engine stalls depends on your particular car's design.

5,000 RPM in gear 1 is usually pretty close to the maximum possible torque, so it might very well be that the hand brake is unable to stall the engine in this condition.
Also note that the hand brake often (usually, almost always) address the rear wheels while the majority of non-pony cars has front transmission. So, while the brake might be able to stop (or effectively stop) the car, it might still not stall the motor. Front wheels might do a burn-out while rear wheels stand still (or slide very slowly). Burn-out with front wheels would be a funny thing to see though, don't think I've seen that in my life.

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Yeah... Currently I'm experimenting with BMW M3 E92 specifications and it's RWD + rear wheel handbrake.

By the way - what is a common torque amount of the handbrakes?

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I can tell you that when I owned a small car (1 litre manual transmission Nissan) it was my first ever car and I accidentally drove it half a mile with the handbrake on. (doh).

It didnt stall at all in first, seemed slightly sluggish in second and stalled when going to third, which is where I realised the problem after a couple of tries, stopping and looking at the dashboard. :P

So yeah for a few cars you have to be in a reasonably high (read: middle) gear for handbrake to stall it.

It doesn't do your handbrake any good at all, BTW. You could factor that into your game if you want realism :)

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That's automaticly in since I apply torque for brakes. Since at lowest gears you get more torque, it can fight handbrake if it's not too strong. Once torque reduces, engine gets unable to turn the wheels as the firctional torque of handbrakes is bigger. From what you told it soulds like the handbrake has sort of low torque.

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That's automaticly in since I apply torque for brakes. Since at lowest gears you get more torque, it can fight handbrake if it's not too strong. Once torque reduces, engine gets unable to turn the wheels as the firctional torque of handbrakes is bigger. From what you told it soulds like the handbrake has sort of low torque.


Yeah, it's only really designed to hold a stopped car from rolling downhill :)

Sounds like you've got the physics sorted nicely then...

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That's automaticly in since I apply torque for brakes. Since at lowest gears you get more torque, it can fight handbrake if it's not too strong. Once torque reduces, engine gets unable to turn the wheels as the firctional torque of handbrakes is bigger. From what you told it soulds like the handbrake has sort of low torque.



Sounds like you've got the physics sorted nicely then...

I wish I would. They feel right, more or less, but they're not that right.:D

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