22 August 2009

Constant speed versus constant fuel?

Accelerator pedal position in the Mini E is very nearly constant when cruising. It might be close to what engineers would call a constant speed control. By contrast, my foot moves a lot when driving a piston powered car in the hills at steady speed. Perhaps the accelerator pedal in a piston car is closer to a constant fuel rate per stroke, and then the vehicle speed varies widely with engine speed, terrain, gear selection, wind, etc. if the pedal does not move.

I have commented to friends about how easy the Mini E is to drive because of the nearly stationary position of my right foot, but I had not mentioned it in this blog until now. Well, last week when my wife was driving she observed that the Mini E brought to mind that old Irish verse "May the road rise to meet you". It never really made any sense to her and maybe it is a bad literal translation but that fact that the car goes up hills so easily without the driver even having to press the pedal any harder brought the verse to mind.

(I'm starting to get slightly worried that my wife likes this car more than she likes me. The law of unintended consequences is always lurking. Perhaps I am not as easy to get along with as the Mini E. Ha ha. Maybe I should learn from my car.)

I have paid very close attention and when I hold my foot as steady as I can, the Mini E does slow slightly on up hills and speed up slightly on down hills. But only slightly and much less than any other car. I missed not having cruise control at first, but figured it was one of those features that they just did not get to in time. Every prototype project has some features that don't get done in time. But with this car, you hardly miss cruise control.

1 comment:

  1. Hi Jim, enjoying your posts.

    One reason the MINI E feels so steady with power might be because electric motors have all their power at almost all RPMs, unlike gas engines that have rev ranges/power bands.

    Great feeling to mash the pedal and just go when at speed, no downshift and no revving.

    I love the feeling of the electric motor, very addicting car to drive.

    Chris #402