Traction Control and Electronic Stability Control

[JejuSoul]

Does anyone have reports of how well these actually work?

Both of these can be turned off, but I am not sure why you would do so. Anyone have experience with this?

The manual suggests turning these off on a dynamometer. Can someone explain what happens if you don't.

 

[mysoulev]

we used to have Aircare here in Vancouver where vehicles were tested on dynamometer to simulate driving condition, the test result won't be valid if you don't turn off ESC.

this car has no emission so this test won't be necessary but i guess it could still be tested for EPA rating.

 

[SoulEV2016]

Does anyone have reports of how well these actually work?
Both of these can be turned off, but I am not sure why you would do so. Anyone have experience with this?

1) Traction control cut the power when a wheel slip.
ABS sensor are used for this.
Only 1/8 of rotation is used to cut the power.
And then, a median power is applied if you keep the full throttle to permit to move forward even on gravel, rain or snow.

Traction and stability use other sensor : yaw sensor.
They permit (1 front and 1 rear) to stabilize the car with action of : cut power + brake 1 or 2 or 3 or 4 brake regardless of the position (the system can brake the front right wheel and the rear left wheel for example).






2) I have a big amount of hours on racing road ... and i love the rainy day because the special alphalt don't let flow the water off the track (that why beginner driver always crash on racing circuit with rain ... and medium speed).

so, you can exactly sense the division of weight (front/rear) and go crabbing with the car without problem ... and test the stability strategy that the builder have integrated in the car.

the direction (steering wheel) is used to orientate the stability system :

- if you run like a pro with against-steer trajectory, the car brake and cut the power (even when you don't touch the brake and use full thottle).

- if you drive like a normal person, the car mitigate the power and brake each wheel to turn the car
in the direction of the steering wheel : but ... at the end, if you are to fast, the car "simply" use a large trajectory (and crash in the safety rail).

That's why run in rainy day fast and brake hard is the better way to learn the weight of the car (and grip of tire).

Traction & Stability is more like for fast speed in snow or aquaplanning of high speed.
On this situation, yaw sensor is a better tool because it can act on each wheel separatly to keep the car in line.

The better example is this : drive at 153km/h ... and truck overtaking at the last 75m (at 90km/h) ... on a curve.
- In a normal situation WITHOUT Stability control, you brake, the car change the division of grip (left/right -front/rear) ... and you crash in the safety rail.
- With Stability control, you brake = the car stay in line ... but braking is more longer (because brake lock/unlock wheels to stay in line).

That's why people are afraid of the ABS function because "the car don't brake !".
But, it's not the case ... the car brake but follow the steering wheel orientation.

 

[SoulEV2016]

traction control is a problem on dynamometer : it's sense the little difference on the reels and restrict the power on motor because the ABS right sensor rip from the ABS left sensor.

stability control is a problem on dynamometer because the yaw sensor is more accurate on static use ... and the car can have echo vibration on the reels, the stability strategy can create echo on brakes because of the static car and moving wheels.

Compare this to the effect of 2 microphones and 2 speaker in the same proximity range : Larsen Effect.

 

[SoulEV2016]

Both of these can be turned off, but I am not sure why you would do so.

i choose the Soul EV for this, too ... because i can turn OFF the traction control AND the stability control.
on normal use (well ... in my country), traction control is a bad point to pass the power on the road.

why ?

because human has the ability to sense the variance of a wheel that slides (body sensation, back, hands, arms) and the delay to retrieve the full power after an traction control "limitation" (of power).

so ... in my case, i can react more quickly on the slides than the traction control, even on STOP and white painting or rain environment (or, more likely, on gravel).

It takes like 1500-2000km to feel the difference and adapt the throttle to the tire and power.
but, with electrical motor and locked transmission, it's very easy ... than a turbo delay or an 4WD sporty car (that's why tires is very important on this 4WD cars ... not on the Soul EV because we can mitigate this on the road).

it's strange, but on the Soul EV, the differential is not like other product ... more like a LSD feeling (you can have more grip when you turn and keep the full thottle, the car turn more inside the corner).

it's cool.

the others car losing grip and don't stay inside the corner ... i have more sporty and less heavy cars than the Soul EV to compare.

the only "low" problem on the Soul EV is the suspension (speed of the coilover, for the tasters).
but hey ... it's a "normal" car after all.

 

[JejuSoul]

Thanks for the replies. Here in Korea there is discussion about a problem on the Ioniq EV.

https://youtu.be/7LvBjOCvaNk

On a very steep curved turn on rough surface the Ioniq slips and fails to make the turn. We assume this is something to do with traction control and that the battery pack for the Ioniq is at the back, making the car back heavy. Hyundai has been investigating this issue from last week. two different users reported this issue. "It's originated from weight distribution and traction control is working for unexpected situation. it makes car inoperable in curved uphill."

I don't think Soul EV has this problem. I have done much steeper curves than this. And I have never read anything about such a problem with the Soul EV. The battery pack on the Soul EV is much better balanced than the Ioniq EV.
There's a discussion about balance here - http://m.blog.naver.com/ecoev/220650295679

 

[mysoulev]

I don't think Soul EV has this problem.

before entering the garage, i have to make a 90 degree turn up a fairly steep driveway, on a wet day if the wheel slips half way up the driveway, i have to back off and pick up some momentum. so the SoulEV may have the same "problem".

 

[mysoulev]

1) Traction control cut the power when a wheel slip.
ABS sensor are used for this.
Only 1/8 of rotation is used to cut the power.

is this in reference to the SoulEV or EV in general, when i floored the accelerator on the SoulEV, i could hear quite a bit of wheel slip before the ESC light came on.

i saw a youtube video that shows a P100D in wet/rain condition go from 0-60 in 2.7s, i heard cutting power to the motor is much quicker than mechanical pumping.

 

[SoulEV2016]

i could hear quite a bit of wheel slip before the ESC light came on.

With the Soul EV (and others cars), you don't have notification of loosing traction if it's to quick (less than a 1/2 rotation of tire or less than 10m and thottle OFF in this distance).

I don't have notification when stability control operate (distance = less than 30m).
the (auto) brakes do the job to keep the car in line of the steering wheel.

traction or stability are notified when the distance is more than 20m on straight line or 50m on curve (usually, when the stability have finished his job ... after the curve).

---

strange reaction for the ionic ... perhaps the front radar/left detector for collision ?
i don't have this situation (very little speed and high uphill with full steering wheel range).

i have underground parking but no problem like this.

 

[SoulEV2016]

i heard cutting power to the motor is much quicker than mechanical pumping.

ABS sensor (on wheels) are used to mitigate the power in the electric motor controller.
it's very easy to do this with electric traction/propulsion chain.

it's more easy to do this with ABS sensors AND Hall sensors in the motor.
electric motor controller use a 4st stage now : vector torque control (current modulation on the motor wire) because chip control and software in the electric controllers are very fast now.

on petrol engine, it's less accurate.
that's why builder use brake to mitigate in a reduced time.