About a month ago, one of my children started learning to drive. Much to our (mutual) surprise, it turns out that I’m the favoured parent to be sitting in the passenger seat, which means that I’ve spent quite a few hours watching a (human) driver learning how to operate a car safely. Most of the time, at least.
As a result, I consider myself an expert in general stuff about driving, automotive safety and the rest, and I’ve decided that this extends to the subject of self-driving cars. I’m not such an expert that I feel qualified to tell you how to you should design such a car, but I do feel that I can give some pretty useful pointers as to what not to do, along the lines of such august previous articles as:
- 7 tips on how not to write a book
- How not to make a cup of tea
- 10 ways to avoid becoming a start-up founder
What we’re looking to do here is consider how a self-driving car should behave if you want it to seem like a(n inexperienced) human driver. Here are some tips.
1. Teach it to stall
This is a key part of learning to drive in the UK, where most drivers (until recently, at least) have learned on cars with manual (that is “non-automatic”) gearboxes. As a result, learning to stall at inopportune moments is a key skill that the self-driving car needs to master. Alongside this is the ability to judder and “bunny hop” when trying to move off having recovered from the stall. Key places to do so are junctions, roundabouts, and traffic lights. If you can get your automatic gearbox-equipped vehicle to stall, you get extra points: impressive.
2. One thing at a time
Single-threaded programming is much, much simpler than multi-threading. This is a stroke of luck, because new drivers can only concentrate on one thing at a time. They can steer, change gear watch your speed (more on this below), observe roadsigns or avoid other road-users, but you shouldn’t expect them to do all at one time. The same should go for the vehicle that you’re designing. Use a random number generator to decide which one of these to prioritise, and then ignore the others until you’re done
3. Full beam all the way
When you’re driving in the dark, you need to be able to see what you’re doing. The best way to do this is to ensure that your headlights are on full beam. All of the time. Some self-driving cars don’t rely on visible light to negotiate the road, but headlights are also important for letting other road-users know you’re there. And the best way to do this is not only to put them on full beam when you set off, but also not to dip them when other vehicles approach. That way, everyone will know you’re there. They may not be happy, but they’ll know you’re there.
4. (Very) Slow is good
Exactly how fast you go shouldn’t be easily guessable – that would make life too simple for other road-users. It’s important to have some sort of algorithm for this, so let me suggest one:
speed = limit/5 * rand (limit/2)
This is a good start, but there are times when you want to add extra surprise: at random intervals, the car should accelerate to about 10% over the speed limit. For added realism, you should be careful to avoid this happening at obvious times such as at the beginning or end of a reduced speed limit – somewhere in the middle is perfect.
5. Fear birds
We live in a rural village, which means that there are lots of birds sitting in the middle of the road most of the time. Favourites are pheasants, partridges, magpies and wood pigeons. Nobody wants feathers (and worse) in their front grill, so it’s important to avoid them. The best way to do this is to make sure that you don’t get too close to them, but this is difficult if they’re everywhere. Fear them. Slow down wherever you can, and not just where you see birds, but where you suspect there might be some – but make sure that other road-users don’t have too much notice. For this, see our next point below.
6. Manoeuvre, signal, mirror (or something like that)
New drivers are taught that there are three important things you need to do every time you do anything like turn off the road, come to a stop or avoid a obstruction (such as birds – see above). These should allegedly be done in a particular order, but real human learner drivers don’t stick to this order, so it’s important to bring a little randomness into the equation. Obviously, self-driving cars don’t need to use mirrors, so in lieu of this, add a little swerve here or there – which is something that learner drivers do when they use their mirrors, so should serve instead.
7. Have a “tutting” passenger
One of the key parts of getting used to driving, as any learner will tell you, is having a passenger next to you, making disapproving noises at (for you) unexpected moments. You’ll need to ensure that there’s some mechanism in the self-driving vehicle to deliver such sound effects. For added realism, you can add panicked cries of “slow, slower, SLOWER, STOP, STOP NOW!” Followed by “Right. We were very lucky there. Get out of the driver’s seat: I’m taking over.” Once you get there, you know that you’ve really succeeded.
- I should point out that to make any extrapolations from this article to the actual driving of the child mentioned above would be grossly unfair.
Title image by Colin on Flickr.