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I was expecting some well funded critical response to that post. As you might have noted, I was not proposing to eliminate mechanical brakes for exactly the reasons described by you. But when you see that major automobile companies turn out cars which do no regenerative braking because this has been deemed 'unsafe' by the KBA, then you might understand that somewhat polemic post. Long before EVs were a topic, system architectures to make that perfectly safe have been thought out. Of course, you would need a high-rate storage element in addition to the battery. AND you would preferably have a redundant resistive element too.
My post was largely influenced by what I've seen in terms of efficiency and usability when engineers can go to work on the EV topic unfettered by the type of rulings applicable to 'normal cars' and the common perception of how a vehicle should be build. I can even see the merit of an ICE, especially if it is running at it's optimum point of operation.
And given my occupation, you can imagine that those examples were related to (mostly thick-skinned) vehicles painted in mottled shades of green.
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I don't know why the KBA think regeneratve braking is unsafe. Do you have a reference preferably in english? Is it completely banned or do they say you must have friction as well?
All cars I know of that have Stop-Start and most if not all with "Smart" alternators use at least a low level of regenerative braking.
You can not of course have just regenerative braking. This is becuase it only applys a retarding force when the rotor is moving. A frictionless system with regenerative braking will take forever to come to a complete stop and will slowly creep if external force (gravity on a slope, wind) is applied. You can of course DC injection brake to a stop. Injection braking consumes power which sort of defies the purpose. There will always be some kiind of friction brake or transmission lock on a car.
All hybrids and EV's use regenerative braking. If they did not they would have no advantage due to the mass of the batteries and motors. My plug in hybrid allows you to dynamically control the amount of regeneration using paddles on wheel. On a highway off ramp with a upslope I can come to a controlled stop without using the brake pedal (regenerative and friction) at all. At high speeds the retardation available from the paddles is so high the system puts the brake lights on.
Currently I can't see any advantage in one motor per wheel for road cars. Unsprung weight is too high for integral wheel motors. Motor speeds are not well matched to wheel speeds so some gearing is needed. Overall with current technology a single motor (per axle maybe) driving a differential gear and two drive shafts is still optimal for road cars. Separate motors and gearboxes add weight and friction losses. For 4WD and heavy vehicles one motor per wheel, possibly with geared hubs / portal axles, becomes a viable option. Controlling motor speed and torque for handling and traction control is trivial wih modern motor drive systems. You could actually dispense with conventional steering and control direction by differential drive with a one wheel per motor set-up. Might need some castoring to prevent tyre scrub. The safety case might be a bit of a challenge and keeping steering may be cheaper than meeting the relability and integrity requiment of a differential system.