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It's sad to see us discuss changing traffic patterns to fix what is wrong with cars.
The original topic was a "peoples car" along the lines of the Model T, the original VW, and many other examples such as the mid 70's Honda Civic with the cvcc engine.
By now most here know my preference for a hydraulic IVT drive located in the area normally reserved for friction brakes.
Massive reductions in power train components, the ability to change the load to maximise BSFC, or eliminate the necessity to modulate electric power delivery to a drive motor, as well as superb regenerative energy recovery percentages, compared to more complex designs.
Maybe one day people will look at the totality of the situation and see a simple solution. That's where I am today.
How much energy do you really need to be able to recover, and how much energy to you really need to apply to eliminate the small percentage of very wasteful periods in daily operation of your car.
Sure it would be great to redesign the roads to match the hypermilers skills perfectly. Sharp upgrades to pulse at max BSFC, with downgrades perfectly matched for engine off coasting.
Ever driven US 1 down the Florida keys? Try making a left hand turn on that road when traffic is heavy, and there are no lights to interrupt the bumper to bumper traffic at 50 MPH. I have watched people sit there for 15 minutes trying to make a left turn, when they could have turned right, made a U turn, and another right turn, in less than 1 minute.
How do you get great mileage in severe mountainous terrain. The lighter car has lower sectional density and would coast downhill at a lower terminal velocity. It would also require much less fuel to climb the same grade. Carrying around hundreds or pounds of batteries in steep terrain means much of your energy capacity is dedicated to increasing the elevation of the battery pack itself.
Having driven my Insight for over 20k miles now, I can see the logic Honda applied to the design of that unique car. I would just change the power train to a hydraulic IVT and the storage to a flywheel or accumulator. Either one would have about the same range capability as the original battery-electric motor combination, which was not very much. I would also reduce the engine size to 600 CC and add an electric supercharger.
I think what is not well understood, by some, is you really don't need much.
How many times do you have to accelerate rapidly to 60 MPH, or stop rapidly from the same speed. That's where your energy losses are the greatest and the storage really only needs to be capacitive to cover the normal stop and accelerate to speed cycle you hate when you get nailed by a poorly timed light.
I have seen objections to high density capacitive type recovery and application because it will not allow recovery of the available energy in severe elevation situations.
To me the best solution to driving in extreme grades is to minimize the vehicle weight, since this directly reduces the total power necessary to climb the grade, but it also means you have less weight behind the same drag forces, which reduces the top speed of the vehicle in a downhill coast.
Now, I know that may not be the best solution, and I would certainly like to hear from those who may have alternatives.
regards
Mech
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