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Drive by wire with no over-rides?

With the advent of sophisticated electronics, modern airliners and now even modern cars are often described as "fly by wire".

The goal here is to use computers to help pilots and drivers to control things with the minimum of effort and to compensate for human foibles in a way that is supposed to improve safety.

Unfortunately, on rare occasions, such fly by wire systems can cause issues, very real and potentially life-threatening issues.

The Boeing 737 Max 8 aircraft crashes that occurred just a few short years ago are perhaps one of the most striking examples of this -- where fly by wire systems were supposed to compensate for critical changes to the aircraft design that would have otherwise made the craft impossible to fly.

Now there's a new danger being created by modern "drive by wire" systems, as one happless UK driver discovered to their cost just the other day.

According to media reports, UK motorist Brian Morrison found himself inside a runaway EV, powerless to stop the vehicle and at grave risk of crashing.

Apparently the MG EV refused to slow down and even the brakes were ineffective at forcing a stop.

Unable to control the speed of the vehicle, which was locked at a constant 50Km/H, Morrison ended up calling police who used a rolling road-block maneuver to surround the vehicle and bring it to a halt.

"Experts" are claiming that they may never discover the bug in the car's complex computer systems that caused the issue -- and that has to be a buge worry for all EV drivers, MG owners in particular. If it happened before, it could happen again and without a definitive fix in place it becomes only a matter of time before the but resurfaces, perhaps with a fatal outcome.

Putting my "skeptic's hat" on for a moment though, I have to wonder whether the driver actually did try everything possible to halt the vehicle.

Surely nobody would design any kind of vehicle for use on the public roads where the brakes were incapable of overpowering the drive-train so as to bring it to a halt in the case of a control-system failure. If that is the case, how on earth can such a vehicle be legally used on the road?

This sounds an awful lot like a cruise-control failure where the vehicle was set to maintain 50KPH and where the computer failed to disengage that cruise-control when it should have. Even so, application of the footbrake or handbrake should have been able to stop the car.

In most EVs, braking is done in two stages... initially by way of regeneration, where the motors are actually switched into "generation" mode so that the kinetic energy of forward movement is converted into recovered electrical energy to recharge the battery. The second stage is good old fashioned brake-pads on disks. Surely that second stage should never be "by wire" and should be an immutable connection between pedal and pads.

Of course it's possible that the ABS system also failed in some strange way such that the braking pressure was never applied to the pistons in the calipers but once again this would seem to be an unacceptable design flaw. ABS systems should never respond to computer-failure such that the brakes don't work -- they should fail such that the anti-lock may not work so that the car's movement can still be arrested.

To be honest, EVs do pose a lot of new risks to drivers and road-users. Perhaps there should be more education as to those risks and the possible mitigations.

For instance, should all EVs have a "master switch" which is operated by a system completely separate to all other systems on the vehicle -- such that the main battery can be disconnected simply by pressing sequence of buttons on the keyfob? This would be the ultimate "disarm" feature that EVs may need, if Mr Morrison's situation is to be avoided and other reports of unintended/uncontrolled acceleration as we've seen reported with other EVs.

The Boeing 737 Max 8 debacle notwithstanding, we don't allow airliners to use fly by wire systems without incredibly stringent third-party testing and verification, so why are some EV manufacturers endangering innocent road users by shipping code that is simply "near enough for a mellow-puff"?

Is it time to introduce standards for the software used in modern EVs? If so, who would administer the certification and can we even be sure it would make any difference to the outcome -- given that *all* software has bugs and it is pretty much impossible to prove the correctness of any non-trivial software system?

Carpe Diem folks!

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