How an EMC problem can kill people and a company

[Mr. Scram]

That's what I mean I feel sad for them.

Also if this wasn't been in the news so big and the government didn't respond so dramatic, the whole investigation procedure would have been different.
I said it before, I agree that some critical safety system seems to be missing, but this way time, effort, money and even maybe a potential very nice product is just completely being wasted. (not to talk about the workers who have to find a new job, also not very nice to have on your CV)
That's what you get when people only think about the problems, and not about solutions, so unfortunate.

As I understand it, an entire vehicle category is effectively being eliminated because of one accident. You have to wonder whether this improves things, as people will now flock to regular vehicles for transportation with all the associated risks and costs. There's a fair chance that things have actually been made worse, but that the cost is hidden in numbers people are already used to.

[Kjelt]

This does not have to be the end.
The inventor/owner can still wait till the storm is over in the mean time invent all necessary safety systems to upgrade the 3500 stints that have been sold and then when the time is right sell these upgrades and restart sales with the safe version.

Paid how?

What do you mean paid how ? 
You mean how the inventor gets paid in the meanwhile?
He pays himself from his savings of his massive earnings he made the previous years on selling the 3500 units.

[b_force]

This does not have to be the end.
The inventor/owner can still wait till the storm is over in the mean time invent all necessary safety systems to upgrade the 3500 stints that have been sold and then when the time is right sell these upgrades and restart sales with the safe version.

Paid how?

What do you mean paid how ? 
You mean how the inventor gets paid in the meanwhile?
He pays himself from his savings of his massive earnings he made the previous years on selling the 3500 units.

No the people you need to make these improvements happen.

[Mr. Scram]

No the people you need to make these improvements happen.

How do you develop a product?

[b_force]

No the people you need to make these improvements happen.

How do you develop a product?

That depends per person.
But a product like a Stint definitely not just by yourself.

[Mr. Scram]

That depends per person.
But a product like a Stint definitely not just by yourself.

So how do products with teams of more than one person get developed?

[b_force]

That depends per person.
But a product like a Stint definitely not just by yourself.

So how do products with teams of more than one person get developed?

At least with some money to pay the wages.

[Mr. Scram]

At least with some money to pay the wages.

How can startups pay for this?

[Berni]

At least with some money to pay the wages.

How can startups pay for this?

By bullshiting investors to give them money. Just like solar roadways, fontus, ubeam etc

[Mr. Scram]

By bullshiting investors to give them money. Just like solar roadways, fontus, ubeam etc

I wouldn't quite describe investments and loans like that, but there you go. That's how it's done. If the owner of the IP of this company can show there's still a viable business, there will no doubt be someone who is prepared to provide them with money to get it going again.

[cdev]

Its good we've discovered now that AC currents running in railroad tracks may sometimes play havoc with the control electronics in some EVs if those electronics aren't designed properly with grounding and shielding throughout so that everything is resistant to them. That seems like common sense.

Putting STRAPPING all the boards grounds at a common ground potential and perhaps shielding all the cables inside of a metal braid sleeve would likely fix it..

That seems like a best practice that most designers would/should be doing but its possible some forgot to, so putting that as a requirement in regulations is a good thing. They probably don't need to specify a testing scenario, just describe the good practices needed to avoid the problem.

[glarsson]

If it plays havoc with electrics in electrical vehicles then it will play havoc with electronics in other types of vehicles. We haven't seen this, so the problem either does not exist of it is already solved. What's left is an incompetent bicycle manufacturer...

[eugenenine]

BTW, has anyone tried turning off their non electric car in any gear while it's moving.
It turns into a pneumatic abs break without the use of any break. the engine itself makes the car stop.Maybe something with a piston cylinder and a solenoid valve can introduce similar safety feature in electric car

I have.  With the particular (pretty average conventional, AFAIK) gasoline engine in my car, opening the throttle doesn't seem to do anything.  It moves air (the exhaust sound changes), but there is little backpressure, so the load isn't much more than the resistance of the engine moving alone.

Then I think your car is broken. Either gasoline or diesel engine brakes with the throttle closed due to compression. This is useful (and strongly recommended) when going down long slopes because your brakes will burn up if you use them. Having the ignition on or off doesn't matter if you have a mechanical coolant pump because that will keep circulating cooling water throughout the engine. Big trucks have an extra valve in the exhaust to create extra back pressure.

More likely his car has an automatic transmission and the difference between the input and output shaft is pretty low when coasting so the torque convertor allows it.

Wife's car was like that, you could take your foot off the gas on the highway and it could take miles before it coasted to a stop.

Even worse was Chrysler's auto transmission which would shift to a higher gear when going downhill to allow coasting.  I had to replace the brakes in ours every fall after driving in the mountains of WV because it prevent ed you from engine braking.  Yes it would actually over-ride what you had selected with the shift lever.

[nctnico]

This does not have to be the end.
The inventor/owner can still wait till the storm is over in the mean time invent all necessary safety systems to upgrade the 3500 stints that have been sold and then when the time is right sell these upgrades and restart sales with the safe version.

Paid how?

What do you mean paid how ? 
You mean how the inventor gets paid in the meanwhile?
He pays himself from his savings of his massive earnings he made the previous years on selling the 3500 units.

No the people you need to make these improvements happen.

You also have to take into account that Stint is likely to receive some big claims. Even with an investor the company may not be financially viable. That doesn't mean someone can buy the IP and produce an improved version (which will take an investment as well). From the information available it seems Stint slapped together some circuit boards from China and made something which works. There isn't even an English version of the software to read the information from the motor controller.

[cdev]

Bicycles are different than cars because of the way the chassis is divided into two parts, with the front wheel rotating and the front handlebars serving as an anchor for the various electronics and "control surfaces". That makes it entirely possible that assuming 'grounding' between the main part of the bike's body and the handlebars (through greasy roller bearings?) wouls not be wise without additional strapping. But people do it, bike mechanics in particular are used to only running a single positive wire for tail lights, etc. Fine for a light but inadequate for digital electronics.. If I was designing an e-bike I would definitely - right at the start- make sure all PCBs were strapped together with a flexible, thick conductor that could not be detached without disabling the entire bike. I could see bad design though, especially when they were designing a really cheap ebike, using a cheap cable harness which might not always make positive contact, or worse, just assuming that the two were grounded when in fact they were not, and that causing problems - even if there was a ground loop larger than an inch or so - a really powerful magnetic field might induce a voltage causing some onboard computer to throw an error and reboot, lets say. (enough to make bits flip?) Reboot might well mean vehicle immobility while the computer recovers. That may be what happened.

Really the worst possible thing that could happen on a train track with a train coming!

Brakes should always be manual and non-electronic if possible! But on some cars, even the brakes are computerized. (this is done to prevent the loss of control that happens when brakes seize up on ice or similar) "anti-lock brakes" a highly desired safety feature.

[eugenenine]

In a car you have two mechanical breaking systems with enough power to fight the engine. The Stint has less control than a bicycle and the breaks did not have sufficient power to fight the engine at full power. The thing was a mess and an accident waiting to happen.

Actually you don't.  That was part of the Toyota problem.  The brakes can stop a vehicle at speed but when the accelerator was stuck full on the brakes quickly overheated and faded to less that useful.  We have random safety stops here and they had me set the parking brake then try to move the vehicle to make sure the parking brake held but if your vehicle is already moving at 70+ mph it takes a lot more force to stop it than it does to hold it already stopped, I haven't seen many parking brakes capable of stopping a vehicle moving at high speed.

[cdev]

The moment either a story like this which indicates a design mistake that could be dangerous emerges or even when they become aware of a potential defect internally, that hasnt impacted anyone, either way, an effected company should go into high gear, not just offering a free retrofit, they should pay to have the retrofit done on their dime, as quickly as possible.

If a customer wants a return rather than retrofit, they should offer to buy it back, maybe for a price that is somewhere between the new price and its resale value without any potential issues. And eat the cost difference.

Turning a potential disaster into an opportunity to build customer loyalty.

If society doesnt incentivize that kind of behavior and strongly deincentivize corporate irresponsibility it wont be long before we have a world where corporations ignore consumer safety, choosing to fight lawsuits rather than fix things. At least here in the US its an ugly secret that lawyers rarely take many kinds of cases on contingency, because even in really egregious cases of error or even intentional abrogation of responsibilities on all levels, for decades - on a big corporation's part, (and that happens all the time with profitable products) the value of a human life varies a lot with many peoples lives simply not being valuable enough in terms of damages to make a lawsuit 'worth it' for an attorney. (Its based on lost income and 'pain and suffering'.) The perception of plaintiffs in cases where some policy or product is at error getting huge damages in court is not backed up by statistics, instead the statistics show a dismal picture of people being injured and not ever getting the justice they need. (or if they have insurance often that insurance contains a 'subrogation' clause which means the insurer gets whatever money they might win, to repay them for whatever money was paid on their behalf, first)

There is a general perception in society that things are supposed to get better for people but honestly, we really need to work much much harder to get businesses to do the right thing, as a matter of habit, otherwise even though we know more now than we once did, it won't translate into more safety.

[b_force]

At least with some money to pay the wages.

How can startups pay for this?

By bullshiting investors to give them money. Just like solar roadways, fontus, ubeam etc

That doesn't happen overnight plus they already have a bad reputation (doesn't matter if it was their fault or not)

I guess filing for bankruptcy makes a lot of sense.
They're not responsible anymore for any claims and customer service.
Once people forgot the name you bring out something similar under a different brand and a different look.

[nctnico]

Brakes should always be manual and non-electronic if possible! But on some cars, even the brakes are computerized. (this is done to prevent the loss of control that happens when brakes seize up on ice or similar) "anti-lock brakes" a highly desired safety feature.

That is not quite right. Even without power braking, anti-lock brakes, etc working the brakes on a car will still work. You'll have to put your foot down harder but they will work. OTOH I doubt that the brakes are powerfull enough to stop the car with the engine running at it's peak output power.

[helius]

The ABS is typically pneumatic, while the main brakes are hydraulic. So the calipers have both fluid and air (or vacuum) actuators. Even removing the ABS module will leave the hydraulic brakes functional (any car with a brake fluid tank has that manual system, assisted with a pressure booster).

[glarsson]

The ABS is typically pneumatic, while the main brakes are hydraulic. So the calipers have both fluid and air (or vacuum) actuators. Even removing the ABS module will leave the hydraulic brakes functional (any car with a brake fluid tank has that manual system, assisted with a pressure booster).

None of the cars I have looked at has an ABS system matching this description.

[helius]

I should have prefaced it with "in my experience..." as I don't claim universal knowledge. Still, I'm curious how else a vehicle with a central master brake cylinder can implement ABS with individual wheel slip detection and response.

[nctnico]

I should have prefaced it with "in my experience..." as I don't claim universal knowledge. Still, I'm curious how else a vehicle with a central master brake cylinder can implement ABS with individual wheel slip detection and response.

Perhaps read first before making assumptions. A car with ABS definitely doesn't have pneumatic and hydraulic actuators on the calipers! There is a hydraulic ABS unit (often called an 'ABS pump') sitting in between the hydaulic line from the master cylinder and the hydraulic lines to the individual wheels. I don't know how this unit works internally but Google should be able to tell.

[glarsson]

I should have prefaced it with "in my experience..." as I don't claim universal knowledge. Still, I'm curious how else a vehicle with a central master brake cylinder can implement ABS with individual wheel slip detection and response.

The ABS system for a car normally has four or three channels. A three channel system does not treat the rear wheels individually.

Each channel has a valve in the ABS unit that can release hydraulic pressure and therefore lighten the brake power. The ABS electronics use wheel sensors to sense wheel rotation nd then decides what wheel/wheels, if any, needs reduced braking force. When a valve pulses the hydraulic pressure you can feel, and hear, vibrations in the brake pedal.

The hydraulic pressure is created, just like in non-ABS brakes, by the master cylinder with assistance of vacuum servo, vacuum pump, and/or hydraulic pump.

If the car has stability support, e.g. ESP, it is usually integrated into the ABS unit. An extra set of valves is used to add hydraulic pressure to one of more brake calipers.

[helius]

I see. Thanks for educating me on the specifics.
In the video nctnico posted, you can see 12 small cylinders in the ABS controller. As they are not covered in DOT4, I presumed that they were pneumatic valves, but without a full understanding. They are actually only the outer inductor part of a hydraulic valve whose inner part is sealed into a separate block.

With the electrical part removed, the hydraulic ABS valves remain in their normal position, which allows pressure to actuate the calipers when the brake is pressed. When the valves are pulsed by the ABS system, they unload the pressure from the calipers which reduces brake force. There is also a motor in the unit to provide braking force independent of the master cylinder for traction control (which combined with electronic throttle control, can reduce power to the wheels if they are spinning due to too much torque).