If they really want hub motors, how much of a compromise would it be to build it more like a transaxle drive. That is, have a short axle with the motor fixed to the chassis - one for each wheel.
As I see it, the main compromise is the additional space needed and a bit more weight (the axles). Plus, it would still have some of the potential failures Bill points out. Peri -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bill Dube Sent: 30 April, 2013 7:24 AM To: Electric Vehicle Discussion List Subject: Re: [EVDL] EVLN: Ford Prototype Electric Car with In-Wheel Motors 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-fu ture-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.j pg >http://www.plugincars.com/sites/default/files/ford-inwheel-detail-under-hoo d-620.jpg >http://www.plugincars.com/sites/default/files/ford-inwheel-back-road-620.jp g >] 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 _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
