iMiEV has a "black box" recorder

Post by **zzcoopej** » Thu, 29 Jan 2015, 00:21

I wonder if the Police would think to extract data from our iMiEV in the case of a serious accident. All sorts of info including speed, acceleration etc. What are the legalities?

Post by **reecho** » Thu, 29 Jan 2015, 00:29

Police not so much....unless it involves fatalities.

Insurance companies on the other hand, are a lot more ruthless.

RAC TCU Snapshot

Post by **T1 Terry** » Thu, 29 Jan 2015, 02:38

Quite interesting findings, it shows there was an error in the throttle control which possibly cause the crash. At -2.5 secs the accelerator was only at 28%, yet the throttle was at 100%, the next 100% accelerator measurement was probably due to a panic reaction, the next 2 recording show zero accelerator yet the throttle was still at 24% then 33% at the point of impact, yet the driver was applying the brake. I think the RAC was very lucky to get away with that one as were Holden themselves.

T1 Terry

Post by **acmotor** » Thu, 29 Jan 2015, 06:13

That may just mean that we don't understand the throttle number vs accelerator number. Maybe 24 is the position for idle ? And there is a skew in the data logging, like a software dash pot. Someone might explain.

Anyway, the vehicle was way over the speed limit in hoon territory and would have taken some time to get there, fly by wire fault or not. The driver just made up some tale about snatching the wrong gear. They usually say it was a roo or cat jumping out in front of them.

As an RAC customer I am quite happy not to be paying premiums to cover high risk driving behaviour of others, not to mention the injustice of getting away with a $50,000 lie.

Agreed though, let's hope the defence lawyer is tech savvy.

Post by **reecho** » Thu, 29 Jan 2015, 07:26

The figures are accurate. Don't assume there is a direct relation to pedal position vs. throttle position especially on cars with servo controlled throttle.

Post by **zzcoopej** » Thu, 29 Jan 2015, 12:45

reecho wrote:
Insurance companies on the other hand, are a lot more ruthless.

RAC TCU Snapshot

Thanks for the info, I didn't realise it was already happening.

Post by **Gabz** » Thu, 29 Jan 2015, 13:38

i thought it was only the EV trail cars which had recorders so that they had solid data for reports.

saying that Tesla and Nissan do too and it reports back to the mothership on regular basis.

Post by **T1 Terry** » Thu, 29 Jan 2015, 14:13

acmotor wrote: That may just mean that we don't understand the throttle number vs accelerator number. Maybe 24 is the position for idle ? And there is a skew in the data logging, like a software dash pot. Someone might explain.

Anyway, the vehicle was way over the speed limit in hoon territory and would have taken some time to get there, fly by wire fault or not. The driver just made up some tale about snatching the wrong gear. They usually say it was a roo or cat jumping out in front of them.

As an RAC customer I am quite happy not to be paying premiums to cover high risk driving behaviour of others, not to mention the injustice of getting away with a $50,000 lie.

Agreed though, let's hope the defence lawyer is tech savvy.

They are all percentage of throttle or butterfly open position, at 28% accelerator position the throttle opened to 100%, this would cause a rapid acceleration and explain the higher speed, then 100% as a panic reaction, 0% yet 24% throttle, that's close enough to 1/4 throttle, then 0% and 33% throttle or 1/3rd throttle. A definite engine management problem, not the drivers, he may well have been a hoon, but that was not the cause of this loss of control, it was a computer fault. The RAC may well have lifted the lid on a can of worms it can't close down again resulting in all fly by wire cars being pulled off the road until a solid answer is found.
There was a series of collisions in the US with another makers car that was fly by wire, all reporting uncontrolled throttle openings, this certainly adds fuel to that fire.

T1 Terry

Post by **Johny** » Thu, 29 Jan 2015, 14:34

Curious that RAC choose to ignore, or had insufficient expertise to recognize, the discrepancy in accelerator vs throttle position.
It would be helpful to look at data not associated with a crash to see normal operation.

Post by **reecho** » Thu, 29 Jan 2015, 16:50

Gabz wrote: i thought it was only the EV trail cars which had recorders so that they had solid data for reports.

saying that Tesla and Nissan do too and it reports back to the mothership on regular basis.

My 2010 I-Miev did have a "tracker"in it.....

Needless to say it's not in the car any more.

Post by **acmotor** » Thu, 29 Jan 2015, 17:27

ok, so we are all armchair detectives.

Just thinking, if this was a fuel injected motor then knowing the injector pulse width ratio may be more useful in establishing the engine power since airflow through inlet manifold is an emission controlled function in modern ICEs.

Keep in mind, the driver reported snatching the wrong gear and not a throttle problem. Needless to say, he was travelling at nearly twice the speed limit at the time.
Terry, I hear what you are saying, but in this situation seems, on the basis of the data presented, to just be hooning gone wrong.
You may yet be proved correct when grandma doing the shopping suffers the same fly by wire accelerator fault ?

Edit: also, when the driver was confronted with the data, his response seemed to be 'oops caught out.'

Post by **iDaVID** » Thu, 29 Jan 2015, 18:00

So do these "black boxes" also track your location etc via the GPS or other means?

Post by **Johny** » Thu, 29 Jan 2015, 18:43

iDaVID wrote: So do these "black boxes" also track your location etc via the GPS or other means?

Generally no.
This article is admittedly old (I think 2005) but indicates the type of data stored.
http://www.crashspeed.com/airbag_control_module.htm

Post by **reecho** » Thu, 29 Jan 2015, 18:45

yes they use GPS for location and 3G (or GPRS) to transmit data.

The airbag control modules do not. They use speed and gyro sensors...

Post by **iDaVID** » Thu, 29 Jan 2015, 19:02

So, if they can track our Mievs either through this "blackbox" or the mobile phone system, the insurance companies (&/or police) could get that info I gather if they investigate a claim &/or accident?

Post by **Johny** » Thu, 29 Jan 2015, 19:10

There appear to be two "black boxes" under discussion here:
1. The ones fitted to iMievs for the Victorian EV trial.
2. The airbag control module.

Number 1 is NOT standard.
Number 2 does not have cell phone connections and is refers to contents of an EEPROM chip fitted to the module that is available to download.

The Nissan LEAF has a system called Carwings that does have a cell phone module but the standard garden variety iMiev doesn't.

Post by **iDaVID** » Thu, 29 Jan 2015, 19:13

Thanks Johny.

I was getting worried there for a bit thinking Big Brother is watching over us kind of thing.

Post by **zzcoopej** » Thu, 29 Jan 2015, 19:53

Johny wrote: There appear to be two "black boxes" under discussion here:
1. The ones fitted to iMievs for the Victorian EV trial.
2. The airbag control module.

Actually 3.
I was originally thinking about the data available via the OBD interface. It certainly has more detail than the airbag, however I'm not sure it takes GPS data as that is a screen on Canion, however for my iMiEV its all blank.