Well, I guess we'll see how Tesla works it out soon. I also prefer the one pedal action as it currently is; I'm just a little curious whether extra regen squeezed into the same amount of pedal travel would make it more difficult to avoid driver induced oscillation.
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P85D - Electric Mechanical Braking System
- Thread starter drewfabrics
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- Driving Dynamics Model S
I'm not seeing the logical connection here. The car with regen on the accelerator also has to cut regen over bumps or risk a skid. So again the car's choice will be between surging forward or using the friction brakes to keep it natural.
How is regen on accelerator supposed to make the situation better?
Walter
Can someone please start a thread advocating to take the regen off the accelerator pedal so that everyone here arguing to keep it on the accelerator pedal will have some place to argue about that?
Nobody in this thread is advocating moving the existing regen off the accelerator.
Nobody in this thread is advocating moving the existing regen off the accelerator.
On my VW e-up parts of the regen is on the initial pressing of the brake-pedal and its perfectly smooth as well. You can choose between 3-4settings of regen on the accelerator-pedal and the rest is on the brake-pedal.
In the most aggressive mode the regen on the accellerator-pedal is very similar to a Tesla Model S.
This works very well and new drivers have no problems adjusting. Best of both worlds from my point of view.
Having driven over many washboard surfaces and expansion joints with the Model S, the regeneration doesn't stop just because the wheels slip a bit. Regeneration always stops and you get that no-brakes feeling in the Prius under the same circumstances. If Tesla puts regen on the brakes it will have the same feeling as the Prius. That's not something I would want. With all the regen on the brakes, TC, ABS, VSC can all work independently of the regen--that can't happen when the brake pedal has regen.
I'm not sure where you're thinking there's value in TC, ABS, and VSC *not* being coordinated with regen. It sounds like Tesla made a different design decision than GM and Toyota when it comes to the risk of a skid from rough surfaces (hadn't read that before,) but there's no connection between the decision whether or not to cut regen when a wheel starts to slip and the decision to put regen on the brake pedal.
My Volt cuts the regen over rough surfaces without my foot on the brake while I'm in L - that's actually when it is most disturbing; being on the brakes already makes it less of a shock and gives me more chance to respond faster.
I think I'd prefer it if regen were more tightly integrated into the rest of what the car was doing - so that it uses the brake pads to make up for regen when there's an issue (due to low temperatures, or high states of charge, or wheelspin,) and uses regen in the place of brakes everywhere it can for best energy recovery.
The decision about how much regen to put on the accelerator is independent of that design approach - and most of the cars already give the driver the choice of two or more settings, including the Model S.
Walter
I think the last sentence was supposed to start "With all the regen on the accelerator,"
I just got back from a drive involving various types of roads and speeds. And I realized why many of us who have had the model S for some time are resisting this discussion of putting regen on the brake. I've learned to drive more smoothly so that I really don't think there's much more regen to be gained. I rarely use my brakes other than the last 5mph at a stop sign or traffic light. In a panic stop situation I like having pure braking, and the occurrences are infrequent enough that I don't see much range to be gained.
Those who feel they will get a lot of additional regen off the brakes are likely unfamiliar with one-pedal driving. Or from an efficiency standpoint they would be better off adjusting their driving style vs braking often and capturing a little extra regen.
Let the objections begin!
wow the straw men keep coming.
Nobody is, or needs to, argue for "a lot of additional regen off the brakes."
Everybody who likes accell regen as it is now, and the limited braking effect as it is now. Terrific. Keep that EXACTLY AS IT IS. !! no changes to the accell regen at all.!!!!
The only change is:
During that rare occasion when you do have to press the brake pedal (because you need to stop faster than the current braking effect from accel lift off) imagine you get the exact same additional braking effect. But the only difference is: instead of making brake dust, you are making electricity.
Can we all agree that making electricity is better than making brake dust?
No matter how much you love having the current accel regen why would that cause to "resist" putting additional regen on the brakes.
Why the fetish with heat and brake dust?
You are correct. Fingers were apparently on cruise control.
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Everyone agrees that making electricity is better than making brake dust, but since it's a rare occasion, why add all that extra complexity and poor brake feel for insignificant gains.
Exactly. And I'd rather see TMC expend those development resources on lots of other features, Model X, Model 3, and the Supercharger buildout.
JRP3
Hyperactive Member
Yeah there seems to be a disconnect with reality. I'm all for A pedal regen, but the ibooster rather eliminates the "complexity" argument against additional regen on the brake pedal. The hardware is there, if the software can make it seamless, why not use it?
The iBooster device and control software exists but it still requires software development, integration and testing - hopefully lots of testing considering its critical nature. I want many things and as I've pointed out above I'm not against brake pedal regen if it's completely seamless. But I don't think there's much there to be gained considering how little the brakes are used, so it's not high on my list.
The reality is that it's all about constraints and trade offs - where Tesla will get the biggest bang for its limited bucks/skilled people. Based on my experience and understanding I would put the effort elsewhere. But we are not going to decide this on a forum, Tesla will make the decision based on much more information and experience than we have here. So there's no point in continuing this debate. I'll agree to disagree and we'll see what Tesla does.
Umm... Electromechanical brakes and the iBooster are on cars in the wild now - every car with the Autopilot sensors has the new brakes, too.
(Much of this discussion has been about what else Tesla could do with the iBooster and dual motors, which obviously can't happen before December, but all of the hardware is already delivered.)
Walter
Umm my point is that Tesla probably includes this functionality on the Ds that will be delivered in December. The "software development, integration and testing" for the simple function of using the brake pedal to trigger add'l regen is already done. It could be part of the reason for the increased range in addition to the power curve of the additional motor.
Those on this thread saying the Tesla can't do what they imagine (incorrectly) that Toyota could not do (use the brake pedal to trigger add'l regn) will probably be shown wrong in December. (They were actually shown wrong with the Toyota/Tesla RAV4 EV already many months ago.)
It is so amusing to see the hand wringing and fretting about the looming prospect of regen from the brake pedal.
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MartinAustin
Active Member
techiesjc
Member
Yes HE is sure... I have a new P85+ that I took delivery of on 9/29/14 at the factory. Today I picked up the car from the Fremont SC. I have the new HW on my P85+ as they had to replace the iBooster (Electro-mechanical brake assist). I only went in to have an AC Compressor Fan noise looked at and get Frunk/Trunk chrome trim kits installed. The service record actually has the Tesla part number for the iBooster called out on the swap out of the part.
thecloud
As rhythm raced inside, the ship came alive
@techiesjc: did you have the "ticking" noise issue prior to getting the iBooster replaced? (See issues on new cars). I have the ticking on my P85, which I took delivery of on 9/28, one day before you did. Haven't taken it in for service yet since the consensus on the other thread was that this was "normal"... maybe not!
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