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Sadly you are wrong with this car. There is no hydraulic piston that connects the break pedal to the breaks. Take a look at the parts and how they are connected. This is becoming more common inside of more vehicles these days as electronics gets more prevalent. The Toyota Prius hasn't had a mechanical break pedal for its entire existance. I think you are confusing the emergency mechanical break that is a wire that connects the emergancy break to the rear hydraulic break system. That is mechanical. But the hydraulic break pedal parts are purely computer controlled.
I too would be shocked if there is no mechanical hydraulic failsafe brake.

I do notice the master brake cylinder on the firewall where it normally is in front of the brake pedal.

Update

Confirmed by inspection. Mechanical connection from pedal to master cylinder.

yticolev is correct
 

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The only minor bug thing is, when you are nearly on a full stop and release the paddle at 1 or 2 miles, the car seem's to set it self on nutral and the car is on the "loose".. but i will get another try of the Niro EV in a couple of weeks for a full week-end and try all of it's feature.!
That is not a bug, but a feature. I believe that the EV has three levels of regen, plus a coast level you activated by trial and error. I hope that level also defeats the crawl "feature" of the other Niros, if so, great!
 

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Discussion Starter #24
KIA has, like many others, gone to great lengths to make the car behave like a standard IC car. In gear, it creeps forward as if in idle, release the throttle and it decelerate as if compression braking but it's all artificial...... Why not use the throttle to go and the brake (pedal, that is) to slow or stop and use max regeneration prior to friction braking and tell the driver when the friction brakes are used.

Please don't mention the 737 Max crashes unless you have, at the minimum, reviewed the flight data traces and have 3000 hrs PIC time in the 737...
 

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No manufacturer will tell you when the mechanical disk brakes are being used. The goal is to make a hybrid seem like a normal car behaves for braking and overcome the well known strange brake blending in hybrids. To do otherwise makes hybrids appear weirder and will cost sales.

Why does it matter when? You already know how to drive the car for greatest efficiency. If you do drive this way, physical brake use is minimized automatically. This is proven by how long the brake pads last on other hybrids. You can do this on manual shift cars as well. It was 140,000 miles on my last car before I had to replace pads. But if you are into jerky driving, your pads will not last as long.
 

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Physics please

Quick correction to an earlier post- it is very much possible for regen braking to be effective down to and including 0 rpm. A classic physics class demo is to short circuit the input of an electric motor and then try to turn it. You can't. Since the resistance is zero, it would take an infinite force to generate an electric field (the motor operating as a generator). There are practical limitations due to the electronic brake controller having to dissipate too much current as you approach zero, but there is no theoretical reason why it isn't possible.
 

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Quick correction to an earlier post- it is very much possible for regen braking to be effective down to and including 0 rpm. A classic physics class demo is to short circuit the input of an electric motor and then try to turn it. You can't. Since the resistance is zero, it would take an infinite force to generate an electric field (the motor operating as a generator). There are practical limitations due to the electronic brake controller having to dissipate too much current as you approach zero, but there is no theoretical reason why it isn't possible.
I think the resistance to turning with a shorted winding is the same as the maximum starting torque.
 

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Discussion Starter #28
No manufacturer will tell you when the mechanical disk brakes are being used. The goal is to make a hybrid seem like a normal car behaves for braking and overcome the well known strange brake blending in hybrids. To do otherwise makes hybrids appear weirder and will cost sales.

Why does it matter when? You already know how to drive the car for greatest efficiency. If you do drive this way, physical brake use is minimized automatically. This is proven by how long the brake pads last on other hybrids. You can do this on manual shift cars as well. It was 140,000 miles on my last car before I had to replace pads. But if you are into jerky driving, your pads will not last as long.
I suppose it's the geek in me. Always wanting to know how and why. I could see KIA starting friction braking as soon as you touch the brake, all the way to only using them when regen is exhausted. The brake light is similar; is it certain regen braking, brake pedal, brake hydraulics pressurized, certain deceleration rate, some combination or what?

Does it matter? To my wife, for whom I bought the car; absolutely not, but to an auto enthusiast on a car forum, it does.

The marketing aspects, specifically making the car seem as "normal" with respect to the purely IC engine car; I understand but I don't have to like it. It just seems illogical but for one small consideration.......people don't buy weird cars.

On the other hand, it's all software anymore so why not? Coasting is more efficient than regen, regen is more efficient than friction so why not let the driver use that if he wants.

The pure EV's are going that way in all sorts of ways
 

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Discussion Starter #29
Quick correction to an earlier post- it is very much possible for regen braking to be effective down to and including 0 rpm. A classic physics class demo is to short circuit the input of an electric motor and then try to turn it. You can't. Since the resistance is zero, it would take an infinite force to generate an electric field (the motor operating as a generator). There are practical limitations due to the electronic brake controller having to dissipate too much current as you approach zero, but there is no theoretical reason why it isn't possible.
Isn't there a difference in resistance braking where power is being dumped into a resistor and dissipated as heat as in a locomotive and regenerative braking where if the EMF generated becomes too little to charge the battery, resistance is only friction?

I think the resistance to turning with a shorted winding is the same as the maximum starting torque.
I might agree if the generator is of the perminent magnet type but not if a rectified alternator. Wouldn't an alternator without a power source exhibit internal friction only. Using more power than you make isn't regenerative braking.
 

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I might agree if the generator is of the perminent magnet type but not if a rectified alternator. Wouldn't an alternator without a power source exhibit internal friction only. Using more power than you make isn't regenerative braking.

"I think the resistance to turning with a shorted winding is the same as the maximum starting torque."

I'm going to take back this comment. A shorted winding does not have zero resistance but it will be less than the battery. Starting torque is also limited by the battery thus less than short circuit resistance torque.
 

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Discussion Starter #32
Coasting is more efficient than regen, regen is more efficient than friction so why not let the driver use that if he wants.
What's stopping you?
Try it. It takes such a fine touch as to be near impossible. I suppose you could select neutral on and off but I'm not sure that would be good for the trannie. Just releasing the throttle would be easy. The premium Niro with nav, I believe, has a coast mode as it looks ahead at terrain.
 

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The kniro.net site has a description of the braking system. The first graph on the page (see attachment) gives the impression that friction braking is used more frequently in normal driving than we might like to think. It also suggests that regenerative braking is doing most of the work of stopping the car at very low speeds close to zero, but that the last drop in speed to a full stop is managed primarily by hydraulic (friction) braking. One can imagine that if you limit yourself to a light press on the pedal, you can probably spend more time in the regen (light grey) than in the friction(dark grey) part of the graph.

This page also points out that in normal operation the braking is managed electrically, but "If the PSU or the IBAU is broken, IN valve and OUT valve are closed, and CUT valve is off. Therefore, the brake force is generated by only pressing a brake pedal manually by a driver. "
 

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Discussion Starter #34
Superb! The big news to me is that the motor is used to regenerate according to that. Units are not mentioned but if the graph is constant deceleration, it makes sense. At high speeds, the gen makes too much energy for the system to accept. As speed decreases, regen is capible of "that" level of deceleration until a very low speed then it's all friction.
 

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Discussion Starter #35 (Edited)
Imagine a series of similar charts with ever decreasing levels of deceleration. The grey area would gradually retreat in speed until, at some level, it would be gone. I'm not really sure how this relates to the indicator, however.

Notice how regenerative braking rapidly goes to 0 at very low speeds.
 

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Try it. It takes such a fine touch as to be near impossible. I suppose you could select neutral on and off but I'm not sure that would be good for the trannie. Just releasing the throttle would be easy. The premium Niro with nav, I believe, has a coast mode as it looks ahead at terrain.
Your first sentence does not reference anything. From your second sentence, apparently you are talking about coasting, not regen braking. Yes, putting it into neutral is coasting. No harm done any more than shifting into drive from a stop. Try it! Revs are matched, no wear on the DCT will result.

But in normal traffic, I find there are not many opportunities for coasting. Instead, I rely on the gentle regen slowing that happens when you take your foot off the pedal (or in my case, release the cruise control). That usually doesn't annoy traffic behind you. In any case, coasting instead of regen (or creep) is a preference. I agree that it would have been better for Kia to let us choose rather than making the choice for us. The workaround if you want to coast is to shift into neutral (not hard). When in neutral, all braking will be mechanical.
 

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Kia (and other companies) figured out it’s best to not be specific because there will be people who will use an indicator to try and eke out as much regen energy as possible and fail to actually stop, causing more accidents.
 

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Discussion Starter #38
Yeah, the lawyers are alive and well. The lane keep is another example. It is far better than the GM version I've driven but still disconnects without a bit of driver participation. Yticolev is correct in that there are few real world opportunities to use coast. With speed limits, traffic and cruise control; knowledge of friction braking is more a novelty than practical.

The geek in me still wants to know.

Niro has kindled a serious interest in a pure EV specifically a Tesla....
 
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