MADISON, Wis. -- Following an Oklahoma court judgment against Toyota for “unintended acceleration” in some of its cars, after which Toyota agreed to settle with the plaintiffs on punitive damages, the greatest frustration for court-watchers has been the blockade on information about what one expert witness referred to as Task X.
During EE Times’ interview with Michael Barr, CTO and co-founder of the Barr Group, who was an expert witness during the trial, he discussed the death of “Task X,” which he believes ultimately caused “loss of throttle control” and also “a disablement of a number of the fail-safes.”
So what is Task X? What tasks is Task X supposed to perform?
Barr said he’s not allowed to talk about specifics on Task X. However, the trial transcript offers ample clues about what it does.
EE Times went back to the transcripts of Bookout v. Toyota Motor and found the following:
On the witness stand, Barr described Task X as “kitchen-sink” function because of an extensive list of chores it’s designed to perform within an automobile’s electronic system.
In the context of the trial, he explained that Task X helps manage throttle control. “It selects the next throttle percentage, whether it should be 100 percent, 50 percent, 20 percent,” he testified. “And it does that based on looking at the accelerator pedal position, whether the cruise [control] is on.”
Further, Task X executes the cruise-control code. This makes it responsible both for turning on cruise control, maintaining speed in cruise control, and turning off cruise control.
More importantly, Task X “also is responsible for many of the fail-safes on the main CPU,” Barr said during the trial.
Excerpts of the court transcript
EE Times is publishing a portion of the court transcript relevant to Task X. The following Q&A was carried out when Benjamin E. Baker, Jr., representing the plaintiffs, called expert witness Barr to the stand:
A [Barr] So the ultimate conclusion from the presence of these defects is that the software could malfunction. And the most dangerous such malfunction would be if the car had a portion of its software that was working, and that part was running the combustion feeding air and fuel and spark to the engine at the same time that the part that the driver was interacting with through the accelerator pedal or the cruise control switches was not listening to the driver because it crashed or hung, like one application might crash on your desktop while another one is still running.
Q [Baker] And are the defects that you're describing here that can cause an unintended acceleration, can that occur when the cruise control is on?
Q Can it occur when the cruise control is off?
Q And it is the same software defects that would relate to both?
Q Let's go to the next slide. You're talking about the software malfunctions here?