steering wheel toggle for drive mode

[TaosEV]

How about a paddle or toggle switch on the steering wheel to switch back and forth between D and Eco? Those seem to be the two modes we're using most on the flats and hills here.

 

[JoeS]

Better yet: have the car always coast when letting off the go-pedal, but have the paddle by the steering wheel provide variable regeneration. I have such a joystick on my modified Gen1 Insight and love it. This concept could be designed so the user could select their preference as, for example, some people like having regen when letting off the go-pedal, so that amount could also be user-selectable.

Gotta get the car makers to stop trying to make electric cars behave like ICE!

 

[jennrod12]

Agree! I'd love it if the car would coast when letting off the go-pedal.

Jenn

 

[Don]

I don't think it's ever going to coast like an ICE car does in neutral simply because we don't have one - No matter what, we still have a 7 to 1 reduction gearbox spinning an electric motor directly connected to the rear wheels . . . . which is why Mitsu warns us against towing the car with the rear wheels on the ground. I suspect the greatest wear and tear to the drivetrain will come from coasting, where the gearbox is spinning the motor, rather than the other way 'round. Supplying the exact amount of current to the motor to keep it 'freewheeling' is probably the best way to go, both in terms of greatest range and the least wear on things . . . . unless and until Mitsu sees fit to give us an over running clutch between the motor and the gearbox like the old manual overdrive transmissions used to have - With those you had a choice of true freewheeling or engine braking at the flip of the overdrive switch. If they ever do that, it would make it the PERFECT car for RV'ers to tow behind motor homes!!

Don

 

[fjpod]

Truth is...that in the normal ICE with automatic transmission, the car is braked by the transmission when you take your foot off the gas. You have to move the gear lever to get into neutral, and this practice is frowned upon, and as Don pointed out, you are not really freewheeling in the imiev.

 

[JoeS]

Don, we are well aware that the iMiEV's electric motor is direct-coupled, and that putting it into N does not physically disengage anything. Yes, the motor is spinning, but with no power being applied (it's shut off by the N switch) it's essentially freewheeling. The wear-and-tear is certainly no greater than keeping it in D.

The mass of our very small motor and transmission is negligible compared to the mass of an ICE and its flywheel and drivetrain. In case you missed it, here's where it's been discussed:
http://myimiev.com/forum/viewtopic.php?f=2&t=232
http://myimiev.com/forum/viewtopic.php?f=10&t=244
… and we had a beautiful cross-section drawing of the motor which I now can't find. Someone?

Putting the vehicle into N is electrically equivalent to keeping your foot balanced on the go-pedal trying to keep the red needle exactly in the middle between the blue and green zones. I submit that simply putting it into N is easier, faster, and certainly less distracting when driving.

The stated reason by Mitsubishi why they don't want us putting it into N while driving is the possibility of inadvertently putting it into R or P, and that we will "lose regenerative braking" (DUH, that's what we want!). See Owner's Manual Warning Page 3-36.

If I were towing the iMiEV, I certainly would want to lift up the drive wheels and not rack up millions of unnecessary revolutions on the motor/drivetrain.

 

[Don]

Putting the vehicle into N is electrically equivalent to keeping your foot balanced on the go-pedal trying to keep the red needle exactly in the middle between the blue and green zones. I submit that simply putting it into N is easier, faster, and certainly less distracting when driving.

I don't know about that Joe - *I would think* that the electrical equivalent of keeping the needle centered on the line between the blue and green zones *would still have some current flowing in the motor* to prevent you either accelerating or decelerating . . . . otherwise, you're effectively using the drag of the unpowered motor and trans for braking

Does lifting your foot off in 'D' still have the forward 'idle current' applied to the motor that we feel when we shift from 'N' into 'D' at a stop? If so, that would seem closer to the electrical equivalent you described, at least to me

Whatever - I still wish it had an electric overdrive clutch in the transmission so you could truly coast when you wanted to. They could hook that clutch to the neutral switch and then we'd really have a neutral
Don

 

[JoeS]

I don't know about that Joe - *I would think* that the electrical equivalent of keeping the needle centered on the line between the blue and green zones *would still have some current flowing in the motor* to prevent you either accelerating or decelerating . . . . otherwise, you're effectively using the drag of the unpowered motor and trans for braking

If I am to believe the Power Gauge is simply an ammeter, then the midway point between blue and green represents zero going into/outof the battery, as the motor itself has no reason to absorb current.

Does lifting your foot off in 'D' still have the forward 'idle current' applied to the motor that we feel when we shift from 'N' into 'D' at a stop? If so, that would seem closer to the electrical equivalent you described, at least to me

Shifting from D to N when the car is stopped and the brake is on (disabling the drive) doesn't budge the needle. Foot off the brake, and you might feel a slight jerk like in an ICE (I'll have to try that to be sure, if I can get our iMiEV away from my wife).

I still wish it had an electric overdrive clutch in the transmission so you could truly coast when you wanted to. They could hook that clutch to the neutral switch and then we'd really have a neutralDon

Agree with you there, but adding a clutch would increase weight and complexity. My old Saab has a freewheel (a uni-directional drive), but that concept wouldn't work for us as our motor reverses direction for reverse. I still believe the N switch electrically disconnects the motor (in both directions) and accomplishes what we want with a minimum of complexity. A more sensitive ammeter would tell us that.

 

[Don]

I understand what you're saying and I'm sure you're right - That 'N' removes all current from the motor and centers the ammeter with no current flow. Certainly the best scenario if you want to coast down a hill or gradually slow to a stop or to make a turn - Probably less energy used than maintaining a steady speed and then regenerative braking just before the turn or stop . . . . I think

I'm still learning how to drive this thing and I'm not sure I really know all I think I know, probably because the car tries it's best in many ways to mimic an ICE with an automatic (especially if you use the 'D' or 'Eco' modes) and we've always had manual transmission cars, which is why driving all the time in 'B' mode seems to work the best for us. We're used to definite engine braking when you lift your foot - We've always downshifted manual cars for added engine braking. My son got my old '86 Supra from me when I had 130,000 miles on it and then he drove it another 30,000 and the guy he sold it to got the original factory brake pads . . . . neither of us had ever changed them

I'm very used to maintaining a steady throttle, easing up a tiny bit to slow and adding a tiny bit to gain a bit of speed and this seems to work really well with this car. I'm getting 60 to 70 miles per charge, discharging down to 2 bars remaining and this with the A/C on most of the time. We're really happy with the range so far . . . . better than we had expected and the performance is certainly more than we ever thought too

Back to the original sugggestion - I'd sure like to see at least one paddle on the steering wheel - Making it user programmable so it does what each individual would like it to do would be SUPER - Shift from 'D' to 'N' for Joe, shift between 'D' and 'Eco' for Taos and I'd like mine to shift between 'D' and 'B' - C'mon Mitsu . . . . let's make this happen!

Always eager to learn more from you guys who have so much eaperience with EV's - Thanks to the forums, our learning curve is quickly improving

Don

 

[jennrod12]

I've just started playing with driving more in D mode in "slow and go" traffic, as opposed to my usual E mode, after reading comments in this forum. I can see the benefits. I still shift to E after I come to a complete stop, so I don't jack-rabbit start, but it's more like coasting when I lift my foot off the go-pedal in D than when I'm in E.

Thanks for all the tips on driving styles, folks!

Jenn

 

[Don]

It coasts more because it's regenerating less - Depending on your traffic situation, that may be a plus . . . . or not. If you're trying to blend in with other traffic and drive more like a 'normal' car in traffic, the 'B' mode works there, as you can maintain everyone else's pace and when they slam on the brakes, you just use regen

I've come to the conclusion that there is no right or wrong way to use the various driving modes - Mitsu gave us several choices and you use what works for you depending on how and where you drive and what your conditions are - I just wish they had given us a more practical way to switch between the modes without having to fiddle with the shifter all the time

All of this has come as a pleasant surprise - I didn't have a clue before we bought the car that it had so many positive features we could actually use. The car continues to surprise me everyday!

Don

 

[JoeS]

Don - for maximizing your mileage utilizing the "shift" lever, you might have a look at the March 15 posting ("Coasting in Neutral") in the Hypermiling thread:
http://myimiev.com/forum/viewtopic.php?p=1210#p1210

 

[Don]

After 3 weeks driving the car, I figured out what I'd personally like in the way of paddles on the steering wheel

For me, one programmable paddle on the right side of the wheel would do it. 3 choices of user programmable functions would be really nice . . . . or, just pre-program the paddle from the factory to do the following:

1.) If you usually use the 'D' mode for most of your driving, allow the paddle to be programmed to activate the regenerative braking function when you toggle it

2.) If you usually use the 'Eco' mode for most of your driving, allow the paddle to be programmed for the 'D' mode when you toggle it, for that sometimes needed burst of power when you need to 'punch it' to get out of the way

3.) If you usually use the 'B' mode for most of your driving, allow the paddle to be programmed for 'Neutral' when you toggle it so the car will coast freely

If allowing user programming would be too complicated or costly, just program all 3 of those permanently so when you're in the selected driving mode, your paddle gives you those three functions. This shouldn't cost much to do and would make the car much more versatile to drive

Don