Well, apparently its Ford's turn to test, and then reject, hub motors.
Every car manufacturer has announced them, built a prototype, tested
them, and then quietly abandoned them. No exceptions to this
inevitable course of action. Porsche learned their lesson in 1890.
Mitusbishi learned it three years ago. Now it is Ford's turn. Every
car manufacturer must learn the lesson for themselves, it seems.
Hub motors look very attractive until you get into the details. Then
the project is crushed under the weight of the mound of negative
engineering details that must be addressed. You discover that to fix
the annoying list of problems become prohibitively expensive, and you
revert the the conventional frame-mounted single motor. In a nutshell:
1) Unsprung weight. (This should alone should kill the hub motor.)
2) Unacceptable modes of failure in a highway capable vehicle. (i.e.
Single wheel locks, sending the car into the oncoming traffic.)
3) Hostile motor environment. Increased weight and cost dealing with
motor reliability.
4) Increased cost and complexity of multiple drive systems.
5) Motor mass and cost is greater because higher torque is required.
(At the same HP.)
6) Brakes get difficult and unusual.
7) The traction wiring is not centralized.
Mitsubishi went from four wheel hub motors, to two wheel hub motors,
and then finally gave in to the inevitable. They actually made up a
new meaning for MIEV. Originally it stood for "Mitsubishi In-wheel
motor Electric Vehicle" and after they threw in the towel on hub
motors it became "Mitsubishi Innovative Electric Vehicle."
Bill Dube'
At 05:23 AM 4/30/2013, you wrote:
http://www.plugincars.com/ford-prototype-offers-intriguing-possibilities-future-electric-cars-127085.html
[images] First Drive: Ford Prototype Electric Car with In-Wheel
Motors By Nikki Gordon-Bloomfield Apr 26 2013
[images
http://www.plugincars.com/sites/default/files/ford-inwheel-detail-wheel-620.jpg
Ford In-Wheel Motor Prototype Vehicle
http://www.plugincars.com/sites/default/files/ford-inwheel-pullingout-620.jpg
http://www.plugincars.com/sites/default/files/ford-inwheel-detail-under-hood-620.jpg
http://www.plugincars.com/sites/default/files/ford-inwheel-back-road-620.jpg
] For many years, in-wheel electric motors have been used in
electric bicycles. Even some electric motorcycles use hub motors to
reduce mechanical complexity, improve efficiency and save space. But
except for a few prototypes, in-wheel
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