The results of a ten-month study by 30 NASA engineers of possible electronic causes of unintended acceleration in Toyota vehicles was released today by the U.S. Department of Transportation (DOT).
NASA found no evidence that a malfunction in electronics caused large unintended accelerations," said Michael Kirsch, principal engineer and team lead of the study from the NASA Engineering and Safety Center (NESC) based at NASA's Langley Research Center in Hampton, Va. Technical Support to the National Highway Traffic Safety Administration (NHTSA) and the Reported Toyota Motor Corporation (TMC) Unintended Acceleration (UA) Investigation, and Technical Assessment of Toyota Electric Throttle Control (ETC) Systems.
Way in the past I was involved in a "sneak circuit" incident, where we used NASA testing methods to discover an unexplained behavior of a process control system where software, hardware, and process equipment where tightly integrated. That process emerged from NASA's work on the BART trains in the Bay Area, where train doors would open without cause, in spite of all the saftey interlocks. At the time, the concepts of "fail to safety" and "fail safe" where just starting. Nancy Leveson was at UC Irvine and participated in some of our "fail safe" software and hardware designs.
For those seeking clarity about how "complex systems" are built, tested and operated, Nancy's research efforts are a good place to start. The concept of Comprehensive Risk Management in Complex Engineered Systems, includes engineering, architecture, human-centered design, and accident models. This is the operational definition of a "system." These elements are inseparable. If the hardware and software are "engineered" so are the processes and the people that participate in them
