Posted on 03/15/2010 3:54:27 PM PDT by dickmc
While the Toyota portion of the article is informative, the really interesting is the authors remarks on:
As anyone with experience in embedded systems will tell you, there are nasty software bugs that can be extremely difficult to reproduce in a laboratory test environment. To illustrate, I'd like to describe one such bug we encountered at the Jet Propulsion Laboratory while developing the flight software for NASA's Mars Pathfinder spacecraft....
much more experience is detailed in the article here which is quite interesting and well worth reading.
(Excerpt) Read more at latimes.com ...
Could be RF interference. There is a ton of RF energy floating around, especially in urban areas and along roads. RF interference wouldn’t be hard to prove one way or the other, though. Half an afternoon with Toyota, a signal generator and PA and I could determine fairly conclusively whether or not RF was the culprit.
This is of no danger to anyone, but a friend of mine has a 2 year old Caddy. When she parks her car on the North side of the local JCPenney store her remote door locks will not work. If she parks on the east side they work fine. The problem only happens there and can be duplicated each and every time. The service dept can duplicate the problem at that location but no where else. The only thing they have come up with as a possibility is the RFID transceiver at JCPenney. Her answer is “just park on the east”.
The F-86 Sabre is a "jet fighter". So is the MiG-15.
Jus' Sayin'.
But do they have 100 million lines of code?
The more I hear the more I think this goes beyond software.
≤]B^)
We have lots of military jets that are "fly by wire". F16, F117 and F22. The aerodynamics of the F117 are such that only a computer can fly the damn thing.
Actually the aerodynamics of most fighter planes are “geometrically unstable” to be flown by controls directly linked to the pilot. Computers make thousands of minute adjustments per second to keep the plane stable in flight.
This isn’t just with the F-117.
Could be a reflection off the building from a high powered FM or TV transmitter nearby, or a harmonic from a combination of sources like that. Anything powerful enough to cause a problem like that should be fairly easy to identify if you have the right test gear and knowledge of how to use it. The RFID transceivers have very low effective radiated power. I doubt that is the source. There might be a cell site on the roof of the JC Penny's that could be interacting with a high power RF source, causing a harmonic that the door locks don't like, too. That would be the first place I'd look.
"The answer is.....is.....42."
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.