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My lambofeeties and chevrolegs get some great MPG!!
My co-worker just left Ford last year, and he said the way they design the motorized foldable mirrors is retarded. Instead of using limit switches to detect when the mirror is folded in or out for motor cutoff, they use locked rotor sensing back at the control module that reads the current draw. It burns out the motor and is only good for a few thousand cycles, if that.
Most of the time they get stuck folded in when they fail. Adding limit switches would require an extra wire or two in the harness, and limit switches cost extra. Anything to shave a few pennies.
My co-worker just left Ford last year, and he said the way they design the motorized foldable mirrors is retarded. Instead of using limit switches to detect when the mirror is folded in or out for motor cutoff, they use locked rotor sensing back at the control module that reads the current draw. It burns out the motor and is only good for a few thousand cycles, if that.
You may not realize but this is how most cars detect the windows up/down as well... It's a very normal design proven reliable. I would guess as reliable as most cheap limit switches with extra wiring, but no real data. If they are having reliability issues, it's their implementation that's crap. A DC motor running at very low load while moving then hits a very short stall period b fore being shut off is not going to cause the motor to burn up. Only if it is stalled for a long time at high current can it heat up enough to cause any damage. Every since time a DC motor is turned on it sees maximum current (stall current). It's not bad for the motor or coils as they are designed for it. Now the amount of time necessary to stall a motor and run at max current is variable based on many factors (including heat dissipation and epoxy used to hold internal wiring). The choice to NOT use more mechanical parts and the electronics to control was not just for $$$ savings but most likely reliability. As I said, if their system isn't working well it's their implementation that sucks. This system has been used reliably for decades in other ways and means gen by other companies (Mercedes example above) with high reliability. Just because he worked there do any make him an expert on all aspects of design. Neither am I, but at least you can easily see for yourself the reliability in other vehicles as comparison.My co-worker just left Ford last year, and he said the way they design the motorized foldable mirrors is retarded. Instead of using limit switches to detect when the mirror is folded in or out for motor cutoff, they use locked rotor sensing back at the control module that reads the current draw. It burns out the motor and is only good for a few thousand cycles, if that.
This is the annoying part. Government requires a side view mirror to be flat. Some trucks have an additional curved mirror I order to avoid blindspots, but the main mirror has to be flat. This is the reason for blindspots, not the fact that it's a mirror. Camera will have a different FOV, a mirror could to if it was legal. Passenger mirrors are allowed a very small curve as long as they state "objects in mirror are closer than they appear". I guess the worry is if the mirror curve throws off your perception you may think you have room to merge when you don't. I assume it side view mirrors got replaced, the camera would have to follow the same rules for vision as the mechanical parts, but it's the government so making sense and being consistent was never their M.O.
Understood, I'm just giving another point of view and pointing out there is plenty of reference data available. I don't doubt your friends intelligent, but until you actually test it and find the right hardware, it's easy to think an idea is better, but without testing and validation, it's just an unproven idea that may or may not be better or worse. I have no doubts the method would work, just doubts that it would be a noticeable improvement for the cost (which is what all manufacturers go by).
I didn't say I wanted it, I am just saying it's already there... And I would imagine any replacement technology would still have to follow the same regulations.
This has not been my experience. Most people have all 3 mirrors adjusted to provide sight behind them. Most people leave the side mirrors to provide just a bit of the side of their car, but mostly providing a view of the lane next to them.