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Discussion Starter #1
I sure am ready to optomize hybrid driving. By that I mean off gas is coasting and on brake is regeneration. If we had a friction brake indicator, we could learn how to optomize slow downs and stops for max regeneration. I have to say, however, I like this car like it is more than any other new car I've ever bought.
 

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I sure am ready to optomize hybrid driving. By that I mean off gas is coasting and on brake is regeneration. If we had a friction brake indicator, we could learn how to optomize slow downs and stops for max regeneration. I have to say, however, I like this car like it is more than any other new car I've ever bought.

You do. On the left side of your dash there is a ECO indicator. The lower part of the dial is for regenerative breaking. Optimum is the point where the line goes from thin to thick. Around that point the car is getting the most power from the electric motor without needing the breaks to slow down.
 

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Discussion Starter #3
I think the key is like you said, "around that point", is it there or when it gets full scale or somewhere else? KIA did such a good job of making it seamless that, unlike some other EV's, I can't tell.

Do you KNOW that's where it is or have a reference?

I just want a little light that lights as the friction brakes are touching. I've even thought of rigging one up. When a bit younger, it would already be installed.
 

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With normal "braking", the mechanical brakes don't engage. If you drive like you own a hybrid, the mechanical brakes will only engage in the last few feet of a full stop. Regen braking at speed can be amazing. Often coming to a stop, I will lower my set speed on cruise control by 30 mph, pretty brisk slowing (same effect as the brake pedal). Of course, I try to slow down earlier, but don't like to annoy traffic behind. I use the "hand throttle" (cruise control) for 90% of all driving above 20 mph.
 

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Discussion Starter #5 (Edited)
I have to ask, how do you know that? KIA blends it so well that the friction brakes could engage when you first touch the pedal all the way to your post. If I knew how big the generator was I could guess by comparing it to the 60hp traction motor. I know that just prior to the "power" zone, the IC is not operating so if the generator was 60 hp equivalent, the deceleration might be the same as the acceleration with just the traction motor. Even that is not necessarily so.

I suppose cruise control deceleration is as good a guess as any as long as its not smart cruise as that has access to friction brakes.

Incidentally the physics of regenerative braking are such that a complete stop is impossible.
 

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Ford Fusion had a "Brake Score" screen. It graded you on how much regen brakes vs. friction brakes you applied.

After a while, you did learn good hybrid braking techniques.
 

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Incidentally the physics of regenerative braking are such that a complete stop is impossible.

Correct, and if you pay close attention you can actually feel the moment when the motor disconnects and the friction brakes replace it - somewhere around 5-6mph or so.
 

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Discussion Starter #8
I think you may be mistaking the sudden release of autonomous braking associated with smart cruise.
 

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Discussion Starter #9
Ford Fusion had a "Brake Score" screen. It graded you on how much regen brakes vs. friction brakes you applied.

After a while, you did learn good hybrid braking techniques.
That would sure be a step forward. If you could reset it easily, you could test just where the friction brakes join in.
 

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I have to ask, how do you know that? KIA blends it so well that the friction brakes could engage when you first touch the pedal all the way to your post. If I knew how big the generator was I could guess by comparing it to the 60hp traction motor. I know that just prior to the "power" zone, the IC is not operating so if the generator was 60 hp equivalent, the deceleration might be the same as the acceleration with just the traction motor. Even that is not necessarily so.

I suppose cruise control deceleration is as good a guess as any as long as its not smart cruise as that has access to friction brakes.

Incidentally the physics of regenerative braking are such that a complete stop is impossible.

Start at the top of a big hill and use one of those thermal laser temp readers on the rotors of your car. Front ones are the best, but do all of them if you'd like. then start down the long hill. Your going to need to press the break but don't let it get deeper than the point where the regen bar widens from the thin to the thick section. Drive down the hill to the bottom and then let the car come to the stop, again not getting deep into the regen section. At the bottom use the temp laser reader to get the new temperature of the rotors. If you were using the friction breaks down the hill then they would be substantally hotter. If they are around the same temp then your using the electric motor to slow down.
 

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Discussion Starter #11 (Edited)
Great idea, I'll try that.

I'll use the E brake for the final stop and use the front ones for temp measuring.
 

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Talking about regen breaking, tried an EV on the last week end! very cool car.. liked the ride, all smooth and verrrryyy powerfull... You can stop the car with the left "paddle shift" behind the steering wheel. it's stop quick and easely without touching the breakes.! there is 4 regen mode on the model.


The only thing is if you are on the cruise system, it won't stop the car with the paddles..
 

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Incidentally the physics of regenerative braking are such that a complete stop is impossible.
Teslas do the impossible then! You can one pedal the Tesla down to a full stop on regen only. Regen is completely independent from the brakes on a Tesla. Only by depressing the brake pedal do the disk brakes activate.

The motor in the Niro is capable of peak rated HP and torque in both acceleration and deceleration. Why would you think not? The bigger the motor, the better the deceleration and acceleration. Both can be awesome unless otherwise limited by software.
 

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Discussion Starter #14
Regeneration is always totally separate from brakes by definition. There is an awful lot of quibbling on the Tesla boards as to whether one pedal driving uses nothing but regeneration or uses the brakes for a final stop. I suppose if the charge resistance is enough the last movement of rotor can be stopped by the stator.....and I stand corrected in practice. I know you realize that the brake pedal is near meaningless any more. Software has access to the friction brakes regardless of pedal operation.

The 60hp motor could be used for regeneration in Niro but I don't think it is. I believe it uses the HSG (hybrid starter generator) for regeneration and engine starting. I hope I'm wrong but all the simplified diagrams I see list them as two separate units. The motor I believe is in the transaxle and the HSG connected by a belt visable under the hood. I don't know how powerful the generator is.

Taking Niro on a 500 or so mile trip tomorrow and looking forward to playing with the IR thermometer in an attempt to see where friction and regeneration relate.
 

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Regeneration is always totally separate from brakes by definition.
Um, no. Most hybrids and EVs (other than Tesla) blend the two when more deceleration is required. And most historically have done a bad job at this with strange braking feel. The Niro/Ioniq are better than most, which is why you are wondering when the hydraulic brakes add to deceleration.
 

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I have said it on a different thread and will say it again here. The brakes on the Niro are effectively a brake by wire. Take a look at the parts and it is a brake sensor. It doesn't have any hydraulic fluid running through the actual break linkage, rather an electronic sensor that tells a computer how hard you are pressing. This is not like a regular car that the brake pedal has a piston that connects directly to the hydraulic brake pump.





The Niro has a sensor that is more of a potentiometer that detects an amount of travel and converts that into an electronic signal that the computer decides how fast the break is getting pushed along with the displacement and then figured out if it needs to engage the hydraulic breaks or not, or the amount of regenerative braking that takes place.


 

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Discussion Starter #17
Regeneration is always totally separate from brakes by definition.
Um, no. Most hybrids and EVs (other than Tesla) blend the two when more deceleration is required. And most historically have done a bad job at this with strange braking feel. The Niro/Ioniq are better than most, which is why you are wondering when the hydraulic brakes add to deceleration.
By definition.... slowing or stopping can use eather or both but the systems are separate. Tesla blends them as well... in certain modes and circumstances. You're right, Niro is sure good at blending them.

I drive my daughter's Lief quite a bit and my daughter can tell when friction brakes start but I can't. Of course regeneration is an order of magnitude better than Niro as it's a pure EV.
 

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Power brake unit is hydraulic and assists braking power. When car fails, it no longer adds power, but the brakes still work, the hydraulic system is still manually activated by foot pressure. Obviously, it takes a lot more pressure than when the power brake system is working. I can promise you the car manufacturers would be facing billions of dollars of lawsuits if deaths occur because a lack of redundant braking circuits. It would be nuts to remove them on cars. Even plane manufacturers where it makes for better engineering resist taking out mechanical systems. On the 737 Max, there were mechanical safeties in place, but the ESU apparently did not allow the pilots to operate them - the last crash the pilots are documented taking the proper steps to correct the electronic controls. Do you want that to be the case in the Niro when all systems go out? Picture driving at 70 mph and your drive by wire brakes and steering no longer work.
 

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Power brake unit is hydraulic and assists braking power. When car fails, it no longer adds power, but the brakes still work, the hydraulic system is still manually activated by foot pressure. Obviously, it takes a lot more pressure than when the power brake system is working. I can promise you the car manufacturers would be facing billions of dollars of lawsuits if deaths occur because a lack of redundant braking circuits. It would be nuts to remove them on cars. Even plane manufacturers where it makes for better engineering resist taking out mechanical systems. On the 737 Max, there were mechanical safeties in place, but the ESU apparently did not allow the pilots to operate them - the last crash the pilots are documented taking the proper steps to correct the electronic controls. Do you want that to be the case in the Niro when all systems go out? Picture driving at 70 mph and your drive by wire brakes and steering no longer work.

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.
 

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By definition.... slowing or stopping can use eather or both but the systems are separate. Tesla blends them as well... in certain modes and circumstances. You're right, Niro is sure good at blending them.

I drive my daughter's Lief quite a bit and my daughter can tell when friction brakes start but I can't. Of course regeneration is an order of magnitude better than Niro as it's a pure EV.
@Mal , You are absolutly right. Thhe Leaf has the same system than other BEV's that can make the car stop with the "forward" pedal.. (can't say gas pedal anymore! hahaha) For Nissan, it's called the "e-Pedal"





Now, for the Niro EV, it's not directly on the "forward pedal", but on the left paddle shifter behind the wheel. and it's fun too use.. did a lot of them on last week-end!
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.!


 
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