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Crittes and Self driving cars

Safety
#1

Dear Ray,

As today’s cars become more automated they require numerous sensors located around the vehicle. I assume the sensors are connected by wires to various controlling modules, and safe operation requires a steady stream of data from the sensors. What happens if an input is interrupted without warning as nearly happened to me when a wire from traction control was hanging on by a single strand after being nearly chewed off by a critter. Also my 4 wheel drive failed due to chewed wire.

Like many vehicle owners, I have a vehicle that is parked outside. And like many owners, I have continuous trouble with critters chewing on the wires. (The manufacturers don’t seem to care about this because the damage isn’t covered under the warranty).

I know a broken wire will throw a warning light and code, but what about one that hasn’t quite severed and separates while driving?

I guess my question is: - as manufacturers add more automated inputs, is the likelihood of failure increased by the additional opportunities for critters to cause problems?

Chris
Easton, PA

#2

Ray unfortunately doesn’t participate here (though we’d be delighted if he did!)

It goes without saying that autonomous cars will have error checking routines that test everything before the car moves, and while the car is moving. If a critical wire is chewed through the car will discover that and shut itself down until it’s fixed. Presumably while it’s moving it will at least attempt to move to a safe location before it shuts down.

There will also most likely be redundancy such that one wire being chewed through won’t disable the whole car while it’s running. For instance, in airplanes the control hydraulics are triple-redundant, which means you can lose the primary and secondary hydraulic systems entirely and still maintain control of the plane because there’s a third system as double-backup.

#3

The auto manufacturers face additional liability for problems when they sell autonomous vehicles. It seems to me that if certain things are wrong, like your critter concerns, the car will park itself until the issues are resolved. It might, or might not, drive itself to the shop when told to do so, but that’s about as for as it would go.

#4

It is not because they don’t care because the problem is a low percentage of vehicles effected and the task of building a vehicle that could not be effected would add an outrageous amount of money to vehicle cost.

#5

Though it would help if they chose plastic insulation that wasn’t derived from plants such as corn. Rodents think it’s food.

#6

Rats! New Cars’ Soy-Coated Wires Give Rodents Plenty To Chew On
https://www.forbes.com/sites/michaeldunne/2017/02/19/rats-new-cars-soy-coated-wires-give-rodents-plenty-to-chew-on/#623a86f3780a

#7

One solution that seemed to work for me a few years ago (with a likely mouse problem) were multiple tins of chewing tobacco. I punched a few holes in the top of each to let the smell escape, and taped each securely in safe places within the engine compartment.
They seem to keep the critters out, and my wires unchewed.

#8

I’m extremely confident manufacturers have considered this. I know some of the systems for self driving vehicles have multiple redundant systems all running in parallel.

A lot of people seem to think that when autonomous vehicles become widely available we’d all at once have autonomous vehicles everywhere. It’s going to be gradual. First systems will also have manual controls so a human can easily take control (this is happening now with Uber cabs in Pittsburg).

These systems are still years away from final release. They’re in Alpha test right now. Which means there will be bugs and problems to solve. Then Beta…which means more bugs and problems to solve.

Try not to judge autonomous vehicles on the technology today. The technology is changing rapidly. Software is changing and growing at tremendous rates. Even requirements are changing based on new bugs/problems they’ve encountered.

#9

Yup. But only when critters are part of the equation.
It’s commonly believed that the probability of failure increases with increased complexity despite the presence or absence of critters. However, modern cars’ failure rates are far lower, and modern cars’ longevity greater, than the cars I grew up with largely DUE to leaps in technology, in design, manufacture, and also in the cars themselves. Much of that could be and often is described as increases in complexity. Ergo, the theory of increased complexity increasing the probability of failure is clearly either incorrect or far more complex than the average person thinks. I think it’s the latter.

What I believe will increase from critter damage because of increased complexity is not the likelihood of a failure, but rather the difficulty diagnosing the problem.