Cruise Control improvements

[N4HHE]

LOL. "Neck snapping"? "Slammed"? Sounds like using the S cruise control is like the Space Mountain ride at Disneyland. I find the sensation of changing 1MPH barely perceptible and the regen upon disengagement gradual.

+1 MPH jerks like a bad manual shift or a hotrod automatic transmission. Tap the +1 CC while watching the power meter: 15-20 kW jumps to 80 kW then falls below 10 before stabilizing back where it was before. No one who has studied control theory would find that oscillation acceptable.

+5 MPH is much smoother now than +1 MPH.

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The +1 and +5 trim works for me. However, when TACC disengage, MS should simply cruise down by removing power to the motor like an ICE, and without regen. Regen may light the brake light and annoy the car following you. It will be up to the driver to decide whether application of brake is needed or not. When driver do decide to apply brake, then both regen and brake may be applied.

Yes, +1 and +5 works but +1 isn't up to the expectations of a Honda or Toyota, much less a Tesla.

Agree that disengaging the CC should not result in aggressive regeneration unless the driver applies the brake.

 

[Shaggy]

My Fusion Energi's adaptive cruise has an 'Eco' option, where the speed is allowed to climb a couple of mph downhill and drop the same on an uphill as it will slowly get back to the set speed. With Eco disengaged, it does it's best to hold the defined speed. Does the Model S' cruise do the same or have a similar feature?

The adaptive part is following time based .8, 1.4, 2, & 3 seconds; so at faster speeds the distance is greater. Does the Model S' cruise do the same or have a similar feature?

When I disengage, the normal regen starts. When slowing the car does NOT have City Stop, so at around 15 MPH, it disengages the break and warns you to take over breaking to a stop. If I read correctly the Model S will bring you to a full stop with it's adaptive cruise and hold the stop?

I never get a chance to play with the cruise on the test drives... so I thought I ask here.

 

[redi]

I find my older CC disengagement to work perfectly - just as I would want. It slows just like it would if I lifted off the pedal, just as expected. Easily moderated if I want something less with the right pedal. If manually disengage the CC it usually means I want max slow right now, just like I'd anticipate. If you don't want this then set the regen to low.

I drove a new loaner recently with the adaptive cc and found that it "hesitated" and rolled off more gradually upon disengagement. Possibly because of the new hardware. I did not like the way it seemed to lag on the disengagement, gradually rolling into full regen.

 

[RAW84]

+1 MPH jerks like a bad manual shift or a hotrod automatic transmission. Tap the +1 CC while watching the power meter: 15-20 kW jumps to 80 kW then falls below 10 before stabilizing back where it was before. No one who has studied control theory would find that oscillation acceptable.

+5 MPH is much smoother now than +1 MPH.

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Yes, +1 and +5 works but +1 isn't up to the expectations of a Honda or Toyota, much less a Tesla.

Agree that disengaging the CC should not result in aggressive regeneration unless the driver applies the brake.

I've never experienced this with changing +1 driving on a relatively flat surface, only when on a hill.

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My Fusion Energi's adaptive cruise has an 'Eco' option, where the speed is allowed to climb a couple of mph downhill and drop the same on an uphill as it will slowly get back to the set speed. With Eco disengaged, it does it's best to hold the defined speed. Does the Model S' cruise do the same or have a similar feature?

The adaptive part is following time based .8, 1.4, 2, & 3 seconds; so at faster speeds the distance is greater. Does the Model S' cruise do the same or have a similar feature?

When I disengage, the normal regen starts. When slowing the car does NOT have City Stop, so at around 15 MPH, it disengages the break and warns you to take over breaking to a stop. If I read correctly the Model S will bring you to a full stop with it's adaptive cruise and hold the stop?

I never get a chance to play with the cruise on the test drives... so I thought I ask here.

No eco mode, it tries to maintain constant speed. For really steep declines it may speed up some, tho.

There are 7 following distances. Number 1 being the closest, number 7 being the furthest. Number 1 is closer at lower speeds than it is at higher speeds. I don't know how each step correlates with time.

Yes the adaptive cruise control will follow the car in front of you to a complete stop. It will not do a good job stopping behind a car that is already stopped in front of you. If it thinks you're on a highway, it will resume as long as traffic resumes within 30 seconds, if it thinks you're not on a highway that drops to 5 seconds. If you're stopped longer than those thresholds, you'll have to manually tell the car to resume (either by pulling back on the stalk or pressing the accelerator pedal).

 

[Andyw2100]

My Fusion Energi's adaptive cruise has an 'Eco' option, where the speed is allowed to climb a couple of mph downhill and drop the same on an uphill as it will slowly get back to the set speed. With Eco disengaged, it does it's best to hold the defined speed. Does the Model S' cruise do the same or have a similar feature?

The adaptive part is following time based .8, 1.4, 2, & 3 seconds; so at faster speeds the distance is greater. Does the Model S' cruise do the same or have a similar feature?

When I disengage, the normal regen starts. When slowing the car does NOT have City Stop, so at around 15 MPH, it disengages the break and warns you to take over breaking to a stop. If I read correctly the Model S will bring you to a full stop with it's adaptive cruise and hold the stop?

I never get a chance to play with the cruise on the test drives... so I thought I ask here.

No eco mode, it tries to maintain constant speed. For really steep declines it may speed up some, tho.

As RAW84 points out, our TACCs do not have any sort of special ECO mode.

I actually suggested the need for something like this within the first couple of days of TACC being released. I'm still hoping Tesla will eventually give it to us. Not only could it save some energy by functioning as your Fusion Energi's does, allowing the set speed to vary some going up and down hills*, but it could also save energy by being somewhat less aggressive when it finds space in front of it and the car needs to get up to speed. It could also slow down sooner, as opposed to having to use regen or even the friction brakes later.

*I'm not sure I'd want TACC ECO mode to exceed the set speed going down hills. Perhaps whether or not TACC ECO mode does that could be a separate, user-selectable option for that mode.

 

[mknox]

I find my older CC disengagement to work perfectly - just as I would want. It slows just like it would if I lifted off the pedal, just as expected. Easily moderated if I want something less with the right pedal. If manually disengage the CC it usually means I want max slow right now, just like I'd anticipate. If you don't want this then set the regen to low.

I've always felt this way too. Even with my old ICE cars, I would always start pressing down on the gas as I disengaged the Cruise so as to avoid the lurch of deceleration unless it was my intent to slow briskly.

 

[N4HHE]

I've always felt this way too. Even with my old ICE cars, I would always start pressing down on the gas as I disengaged the Cruise so as to avoid the lurch of deceleration unless it was my intent to slow briskly.

Yes, but the ICEmobiles do not engine brake so hard as to warrant illuminating the brake lights.

Also most ICE CC's physically move the accelerator pedal so one can apply foot and find the current CC position to take over from. On the Model S one has to press the accelerator enough to drive faster than the CC to be able to disengage smoothly, reliably.

Knowing enough about the mathematics of control theory to be dangerous, I believe my Model S simply changes the desired speed when +-5 or +-1 MPH is selected. Lets the standard equations deal with the error. The reaction is sudden and excessive. And upon reaching target speed there is another excessive overreaction. Just watch the kW gauge.

On my M-class the +-1 MPH trim can not be felt or seen as a blip on the tach. +-5 MPH is also a smooth change. Disengaging cruise results in typical ICE automatic transmission "creep" grade of engine braking: not much. No matter its a diesel. The M-class CC doesn't move the accelerator pedal but with so little engine braking one can wait to press the accelerator until after the CC has disengaged.

 

[mknox]

Yes, but the ICEmobiles do not engine brake so hard as to warrant illuminating the brake lights.

But I guess what I was saying is that if I don't want that to happen, I just depress the accelerator as I disengage, but there may be circumstances where I do want rapid deceleration and then this would be a good thing since I wouldn't have to jump on the brake as quickly.

Also most ICE CC's physically move the accelerator pedal so one can apply foot and find the current CC position to take over from. On the Model S one has to press the accelerator enough to drive faster than the CC to be able to disengage smoothly, reliably.

I don't think I've had an ICE physically move the pedal since the '80s when cruise control was a manual affair that just pulled on a cable attached to the throttle linkage. All of my recent cars have behaved exactly like the Model S.