By Stephen Evans
BBC News, California
Scientists at Stanford University in the US are attempting to turn the car into a friend for life, by getting it to talk to you in a way that puts you in a good mood for safe driving.
Talking cars might be able to warn drivers of approaching hazards
I have seen the future of the car and it is a friend.
Or rather, I have heard the future of the car, and it is a friend.
In fact, it speaks very like you do. It has the same intonations and figures of speech and patterns of grammar.
You talk to it, and it talks back to you in a helpful way. It is your buddy.
'Human guinea pig'
I know this because I have been to the Communication Between Humans and Interactive Media Lab (CHIMe) at Stanford University which does much of the work for the world's big car companies.
So the question is: how should your car talk to you so it does not make you angry and so, the research shows, a worse driver?
It is important that the car gets its soothing words right
The answers are found in darkened rooms at the lab.
When I was there, a human guinea pig was sitting in a car seat. Ahead of her was a screen with a road, and traffic coming towards her.
She had a rear-view mirror on which she - and I - could see the cars disappearing behind.
The driving conditions can be changed so it feels to the driver in the simulator that it is windy or the road is slippery.
The driver was wired with sensors to detect heartbeat and perspiration and all the other physical signs of calmness or tension.
And in some tests, the faces of the drivers are videotaped.
Safer, smarter driving
So what do we learn?
The first thing is that people who are feeling down react best to a very depressed, boring car voice. They drive worse with a chirpy, "let's turn that frown upside-down" sort of voice.
They may have them in films, but can cars have personalities in real life?
Professor Clifford Nass, whose laboratory this is, concludes that the proverb "misery loves company" is completely wrong. It should be "misery loves miserable company".
In his spare time Professor Nass is a magician, but not one of those ever-so-clever ones who gets the trick right first time.
He is a psychologist and he knows that the way to win audience sympathy is to show vulnerability, so he gets the trick wrong, then wows the audience by getting it right in a final, unexpected flourish.
The magic he is working for the car companies is to devise the right voice to make driving safer, certainly, but also a voice that gives the car a character that you like, so it seems like your friend or the other half of your driving team - you and the car.
As he puts it: "A team mate bucks you up when you're down.
"A team mate takes over when you need it to take over. And people luuuurv team mates."
Professor Nass told me that a Japanese car company developed voices that warned drivers they were driving badly.
Perhaps cars could say "feed me" when they need to recharge
But laboratory tests then showed that the voices made the driving worse.
The first voice said, for example, "You are not driving well, please try to drive more carefully." This annoyed drivers and their driving worsened, prompting the next message: "Please pay more attention and drive more carefully."
Things went from bad to worse until... "Pull over now, please!" The by-now-pretty-angry driver ignored this, and it all ended in a crash... happily only in the lab.
So it is important that the car gets its soothing words right.
If someone else cuts you up, for example, your car should not say, "What a jerk!", as Professor Nass puts it, but something like: "That was a really bad piece of driving. I thought you handled it really well."
Professor Nass's tests show that driving improves when the car explains why it has done something.
So it might tell you it grabbed your steering wheel and pulled you over because you might not have noticed there was a truck coming the other way.
Best friends forever?
The professor's star-turn though, is his work on voice mimicry.
He has done experiments which show that we like it when people copy us, but hate it if the copy is so close that it is mimicry.
So he has developed a way for the car's voice to change as you, the driver, talk to it. And that, he says, is what humans do unconsciously.
And herein lies the route to nirvana for the big car companies.
Imagine if the voice of your car morphed, by mimicking you, and got to seem familiar. Like your trusted friend or buddy.
The companies were initially worried by this development and feared people would be loathe to sell their cars. It would be like relinquishing an old, frayed but faithful friend.
But what if the character of your old car could just be transferred to your new one, simply by moving a cheap computer chip?
That, the companies thought, would be simply brilliant. They could then say: "If you buy my brand, your old buddy will be with you. Buy from another company, and you're starting from scratch."
As Professor Nass told me: "They think this is the greatest possible thing they could possibly have. They could make you effectively stick with their brand at almost no cost to them and unbelievable profit".
So in future, your car could be your friend for life. And if that's the case, who needs humans?
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