Saturday, February 4, 2017

Nissan Qashqai: Sudden Unintended Acceleration?




Driver who killed woman denies mistaking accelerator for brake


2 February 2017



Ann Diggles told Preston Crown Court that her car would not stop before hitting a pedestrian


A driver whose car surged forward and killed a pedestrian has insisted she did not mistake her accelerator for the brake.
Ann Diggles was trying to park her Nissan Qashqai when it hit Julie Dean, 53, in Leyland, Lancashire, in 2014.
The 82-year-old denies causing death by dangerous or careless driving and claims a vehicle fault was to blame.
She told Preston Crown Court: "There is quite a gap between the two pedals. There is no way of mistaking them."

'Lengthy driving career'

Lawyers for the retired nurse said a malfunction in the automatic car's electronic throttle caused by an undercharged battery led to the vehicle surging forward of its own accord in an "uncommanded acceleration".
Prosecutors claimed Mrs Diggles mistakenly pressed the accelerator pedal instead of the brake.
Prosecutor Richard Archer said: "You cannot come to terms with the fact that, after a lengthy driving career, you made such a fundamental mistake."
She responded: "If I thought I could have made this mistake, I would have said so and not put myself through nearly three years of waiting."
Earlier, she told her barrister Alistair Macdonald QC, that she knew her car "like the back of my hand" and the pedals of the brake and accelerator felt "totally different".

Brake 'not working'

The crash happened as Mrs Dean stepped out of a charity shop.
Mrs Diggles, who was attempting to park, said: "I went into drive and I put my foot very gently on the accelerator to cross the road and then the car just took off. It surged forward.
"I can remember taking my foot off the accelerator quickly and I'm sure it went on to the brake and the brake didn't appear to be working.
"Then I saw this lady. I think she had her back to me and it just wouldn't stop before I got to her."
The trial continues.


Its very simple to design a fail safe. For example the pedal operates two potentiometers in opposite directions. This will give two pedal different position signals which can be checked against each other, yet don't behave the same in a failure
If you take a pedal sensor apart you'll see that is exactly how they are designed, there are multiple resistance tracks rather than just one. Also designed so that a break in a track or failure of the wiping contact results in a safe failure mode. The angle sensor at the throttle end uses a similar scheme.

http://www.pistonheads.com/gassing/topic.asp?h=0&f=23&t=1650498&i=40


http://www.bbc.co.uk/news/uk-england-lancashire-38...
article said:
A driver whose car surged forward and killed a pedestrian has insisted she did not mistake her accelerator for the brake.

Ann Diggles was trying to park her Nissan Qashqai when it hit Julie Dean, 53, in Leyland, Lancashire, in 2014.

The 82-year-old denies causing death by dangerous or careless driving and claims a vehicle fault was to blame.

She told Preston Crown Court: "There is quite a gap between the two pedals. There is no way of mistaking them."
"If I thought I could have made this mistake, I would have said so and not put myself through nearly three years of waiting."
more
http://www.bbc.co.uk/news/uk-england-lancashire-38...
article said:
akuma Nakamura, who is responsible for engine control systems development at Nissan, was asked by prosecutor Richard Archer: "Is it possible, in your opinion, for a malfunction in an electronic throttle to cause sudden acceleration of the vehicle?"

Mr Nakamura replied: "I think that's impossible."

He said the system, in which the computer rather than the driver controls the throttle opening settings, had a self-diagnostic feature and that any problem would have been recorded.
He didnt fully discount that it was possible
The problem is that if the software has crashed - how do you know whats going to be recorded?

http://www.pistonheads.com/gassing/topic.asp?h=0&f=23&t=1650498&i=0




Markbarry1977
346 posts
17 months
Yesterday (13:25)
My gut instinct is that the dear old lady has probably by the law of averages got the wrong pedal but firmly believes she
hasn't.
Having said that, how many times have I had to restart a pic or iPhone.
In my previous job I wrote software for a specific air traffic control system. The software had been in use worldwide for
some 20 years. One day in a simulator running regression testing on a new modification there was a major safety error in
the software found, nothing to do with the new change but in the original baseline software. Admittedly the scenario and
user/operator switch and key actions requires to trigger the error were very specific and the chances of it happening
millions to one but a student controller during a free play session happened to trigger it. He argued that it had happened
we all said no you must have imagined it. In the end we replayed a recording of the test session. He was right we were
wrong and all resources were dropped on everything to fix this problem.
My long winded point is that even when someone says it's impossible, there's always that one in a million sequence of
things that can cause unexpected errors.