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Short and concise statement from Police Scotland:

> Around 10.35pm on Sunday 1 October, we received a report of a driver unable to stop his electric car on the A803 heading towards Kirkintilloch. The car was travelling at a low speed and officers carried out a controlled halt with the aid of a police vehicle. There was no damage to either vehicle. The driver arranged for the vehicle to be recovered

I know nothing of electric vehicles, but couldn’t he turn the vehicle off?
I don't think it has a 'power' switch that you can flip to cut power. In fact I'm not sure many ICE vehicles will do that these days. If I press the 'engine start / stop' button in my car while I'm not stopped, I don't think it will stop the engine.
>I don't think it has a 'power' switch that you can flip to cut power.

There should be.

And an entirely manual brake.

In gas vehicles pressing and holding it should turn it off you are in motion.
It will also turn off power brakes and power steering, making it really hard to control.
It is exaggerated, when you're moving it's much easier to steer. The hydrolics will also stay pressurized for a bit, long enough for you to get to the side of the road. The scenario where you need to cut the power probably means the small risk is worth it.
It will if you hold it down long enough.
According to a more extensive, and more lurid report [1] the driver "tried the park button, engine off button, everything"

It also says "Police worked with their engineers and tried everything" - even taking the car key out of range by passing it out the window to a police car driving alongside.

[1] https://www.thescottishsun.co.uk/motors/11320530/electric-ve...

I now am an advocate that the driver should be able to reach the fireman's disconnect for the battery from inside the cabin seated in the driving position.
For others who may have been curious like me:

MG Motor UK Limited (MG Motor) is an automotive company owned by SAIC Motor UK, headquartered in London, owned by the Shanghai-based Chinese state-owned automaker SAIC Motor. [0]

[0] https://en.m.wikipedia.org/wiki/MG_Motor

I wonder what happened here. Isn't it a requirement for cars to have emergency brakes for situations when the normal method of braking fails?
The handbrake is usually fully manual, but it's also not terribly strong especially against an electric motor in its optimal torque region. That leaves you with the regular brakes. Now, I don't know if they're vacuum-assist hydraulic or brake-by-wire on electric cars such as this ..
Every car has some form of brake by wire today. The independent traction control and stability manager relies on electronic intervention between the pedal and the brakes. Even on hydraulic systems they have actuators (a box under the hood) between your master cylinder and caliper.
I drive an almost 20 year old car. I'm going to have such a future shock when I eventually get a new one :(
I got a work trim truck about 5 years ago. No camera, no OnStar, no Bluetooth, no key fob, regular turn key, manual parking brake, etc. It's actually very basic and I love that. It was cheaper than any midsized or large SUV.

I would love it if I could keep it and turn it electric one day. Once the battery densities are 1kwh/kg it would probably swap nicely by replacing the engine/accessories/gas tank with batteries and replacing the transmission with an electric motor. The electronics in most electric cars are a turn off for me. I want it to be simple.

They've been doing this for nearly 30 years now, to varying degrees. It all started with ABS. Then they added traction control, then they added regenerative braking (for EV's) and so on. It's been decades since your brake pedal has had a direct mechanical connection to your drums and your calipers. Even ABS adds computers and sensors between your pedal and the brake.

Generally, these systems are very reliable, but occasionally things go wrong. So far the analysis has been over an order of magnitude of lives have been saved by using this technology than have been lost due to its going awry. Ultimately, this is the argument that's going to be used for self-driving cars.

Regular braking on electric cars partly involves the motors themselves - this regenerative braking helps to convert the kinetic energy of the vehicle back into stored energy in the battery by turning the motors into generators (vs. turning it into as heat as happens with standard friction brakes.) If you ever drive an electric car, you'll find the "engine braking" (i.e. the slowdown you get when you take your foot off the accelerator pedal) is quite a bit more pronounced than on an ICE car.

There are also friction brakes of course, but it's possible the driver, standing on the pedal to try and slow his runaway car, had caused them to overheat, which renders them completely useless.

The slowdown when taking your foot off the pedal is set by the mfg. it is by no means universal even if it’s common to have significant braking. Some cars are tuned to mimic the coasting of ice vehicles.
Handbrakes are frequently being replaced by electronic parking brakes.
Both of my old-fashioned ICE cars have electrically actuated handbrakes. Audi/Volkswagen started implementing them at least 10 years ago.
If you got a steel wire parking brake you won't even notice pulling it at speed on many models. (Don't try this at home ...). You can usually apply more torque on front wheel drive with the motor than the brake can hold since the front is heavier.

Newer cars usually have some electronic parking brake that might just refuse to do its thing. And the key is not connected to a relay over the batteries usually nowadays.

ABS vents can lock you out from using the main wheel brakes.

Welcome to the future of drive by wire cars.

I hate electronic parking brakes. WTF are they good for in an emergency? I guess that's why they call them parking brakes and not emergency brakes. Are we really that lazy that we can't put on a brake manually anymore?
They've never been strong enough to stop your car in an emergency if the engine is running away.

Anyway, the reason they've gone electronic is to add hill assist. Let your foot off the brake and you stay in place until you hit the gas. A lot of people like that.

The hill assist is done through hydraulic actuators of the regular brakes.

Emergency brakes won't bring you to an immediate stop, but they do slow you rapidly if properly adjusted. If your engine is running away, shifting to neutral or killing it is more important.

Ye I dislike them too. I can never learn whether to push or pull the button without mechanical feedback from tightening a wire.

It is somewhat easier to start in hills if you are bad at matching the torque. I guess that is the marketing benefit. However of the computer messes up the release you are in a bad spot if e.g. half way stuck in a ditch or whatever.

Edit: If you have anti roll back braking the vehicle need to be able to engage the parking brake itself so that the fail state isn't that the car starts to roll again.

On my hybrid Fusion, if I push the button for the parking break while it is moving then it pulses the parking break. Which I suppose is good for a controlled slowing the vehicle down. If it is barely moving then it locks the parking break on and stops instantly, but anything over a few miles an hour gets the pulsing (and slowing) action.
Actually, I've had cars with manual parking brakes that had the anti roll back. So the fail state would be that the car starts to roll again. I've never had it fail though. It doesn't seem like that would be a terrible condition as you'd be back to it being a normal car and you weren't in motion anyways.
Because most modern car brakes are complex beats with tons of electronic wizardry. So parking brakes are using those existing electronics. Makes sense.

Not that it would mean much simply being mechanical, I have a car where the parking brake mechanically enganges at the rear prop shaft. And believe, all that brake does is supporting parking if the road isn't too steep.

> Isn't it a requirement for cars to have emergency brakes for situations when the normal method of braking fails?

No. Cars usually have parking brakes, which can be more or less useful as emergency brakes, but that is not their primary function and they are not designed or usually very useful for that purpose for a vehicle stuck with more than minimal power being applied.

This article (https://www.thescottishsun.co.uk/motors/11320530/electric-ve...), which features a picture of the driver looking displeased, doesn't mention the emergency break but says that he tried everything, even turning off the engine. Police had engineers from the car company on the phone trying to come up with ways to stop the car. I have to assume the emergency brake came up as an option.

Maybe activating the emergency brake requires using a touch screen?

The emergency brake is probably electronic and it wouldn't shock me if it was locked out if the car was in motion or defeated by some other similarly idiotic assumption. I hope I'm able to be buried in my 20+ year old cars at this point.
I think the MG4 has a brake by wire system, although those are supposed to have a failsafe built in but if it's not electro-hydraulic there might not be a mechanical link between the pedal and the callipers. Handbrake will be electric too, so activation depends on enough of the car brain functioning.

Keyless ignition usually has an override for a running car too, in a ford pushing the button three times within a few seconds turns the combustion engine off. Wonder if that's the same in electric cars, otherwise the only way I can think to kill it is isolate the batteries, same as emergency services would do in an accident.

Another, more detailed account link to elsewhere in the comments pointed out that the police were even on the phone with engineers from the car manufacturer - if there was such a magic sequence apparently it didn't work. Yeah! Software Everywhere!
There's the parking break, but depending on how fast you're going it might be a bad idea to use that instead of crashing in a straight line (you probably gonna swivel)
the "emergency" brake is actually the parking brake. it cannot hold up against engine power. if you have a car you can try this yourself.

apparently the car in question was stuck in a mode where there was a constant torque request (throttle setting) that was enough to overpower the brake. or, the car helpfully wouldn't allow engaging of the parking brake while the car was still in "D" mode.

i would also have tried opening the door. many cars will take the car out of gear when a door is opened. (frustratingly to me, as it can in rare occasion be helpful to crack open the door when in reverse, to look down for parking lines etc. a very loud warning chime would be better for me personally than this nanny feature.)

60 Minutes had a program where they looked at cars that did not stop when you press the break. And all of their tests, no matter what, even if they were holding down the gas pedal, pressing the break, brings the car to a stop.

Unless there is shown to be a physical defect or fault that prevented the brakes engaging, I am inclined to believe the driver is at fault.

I'm sympathetic to car manufacturers in situations of very brief unintended acceleration, where the driver could plausibly have hit the accelerator instead of the brake, or something loose in the car could have got stuck under one of the pedals.

But in this case, the problem lasted long enough for the driver to call the police, and a convoy of police vehicles to escort him for some 15 minutes.

To me it sounds like the driver's reaction was calm and controlled, with plenty of time to assess the situation. Another report on the same incident [1] says the driver tried the park button, the engine off button, police got advice from engineers, they even tried passing the car key to another car. And that the dash showed "nine warning lights."

Given these facts, it seems very unlikely the driver was, for example, confusing the accelerator and the brake, or failing to press the brake sufficiently hard.

[1] https://www.thescottishsun.co.uk/motors/11320530/electric-ve...

Time to make a phone call doesn't necessarily mean anything. This poor family[0] had time to call 911 and still crashed.

https://www.twincities.com/2010/02/23/a-lexus-barreling-out-...

The article says that the driver was met by a convoy of police cars and then after a 15 minute drive around with the police escort, they did a rolling stop.

I could imagine someone making a mistake and accidentally pressing the wrong pedal, etc., but it seems very unlikely that after 15 minutes at 15mph in a police convoy, the guy still couldn’t work out how to press the brake pedal properly.

"Unless there is shown to be a physical defect or fault that prevented the brakes engaging, I am inclined to believe the driver is at fault."

What about an electronic defect?

That's the interesting part to me - you're relying on the data logs from a system for court which in theory might not match what actually happened and may not leave an observable physical defect. For example but not specific to this case, if there was an error that actuated a brake through the traction control system but it wasn't recorded due to the initiating error.

https://www.thescottishsun.co.uk/motors/11320530/electric-ve...

> Police worked with their engineers and tried everything to bring the EV motor to a stop.

Your thoughts?

Was this the good old "Toyota unintended acceleration" fiasco? I still don't know who to believe on that one.
I guess Toyota is not the only car that moves forward even after you break.
brake
Fly by wire - controlled by software. God help us all.
Worst viral marketing campaign for a reboot ever? Speed 3: Slow & Steady