Flying By Wire

[gregers]

I'm done now.

 

PHEW................ :) :)

Edited November 20, 2009 by gregers

[seatkid]

Just like to add my 2p worth.

 

I run an electronics manufacturing business and having designed safety critical software and hardware for many years in the past, I feel qualified to comment.

 

Some relevant points first

Cable operated throttles - I've seen and heard 1st hand accounts of more stuck open throttles than broken cables. My sister had a mondeo that, at the thottle end, slipped off and jammed the throttle wide open. They are not fail safe really.

 

Don't assume engineers are smart or thorough with their thinking. They are under pressure to spend as little time as possible on a problem from many directions. I know myself what a headache it is. Probably only NASA engineers get paid to keep thinking about the risk of killing someone.

 

The reason that the ECU software is the way it is, is because it was a simple solution that a lot of (not so bright) managers can understand, and it took no time to think about or implement. Simple and cheap solution.

 

BUT, in this case, restarting the car, resets the problem - this is not because it "knows the zero point" - you can start a car with your foot on the throttle pedal - its just because the dual pot sensor agreed with itself. A little more thinking/testing/looking at past experience would suggest that this can be done on the fly, i.e. restore control if the sensor starts behaving itself. Put in some limits maybe, light a warning light, whatever.

 

In the end, I can dip the clutch, brake hard, switch off the ignition etc

 

I have some suspicion that accidents have happened because of this kind of event - maybe even fatal ones - only to be put down to driver error by investigators. In the end, I know why it like it is, but if more people are aware, they may think twice about that "risky overtaking maneuver" that I'm sure we've all done on occasion.

Edited November 21, 2009 by seatkid

[Scorpiorefugee]

Hear Hear!

 

But will anyone listen?

 

I hate to think what may have happened if some young mother with children aboard had been driving instead of you and the white van man had not been so understanding.

 

Probably down to driver error as you say.

 

I used to teach electronics and agree everything you say. The solution is not beyond the reach of any good O-level student.

[big_kev]

Before we get carried away with potential dodgy electronics........

 

 

 

Please remember that nearly all accidents ( 99% +, if not more ) are caused by the pilot control unit malfunctioning .