How to test self-driving car software?

Cars are complex machines, blending electronics and mechanics that whizz down the highway at speeds of 60 miles per hour or more. As drivers, we don't necessarily want to think about it, but the fact remains that there's a lot that could go wrong. And this is with our hands on the wheel, eyes on the road, and feet on the pedals. Introduce the concept of autonomous vehicles controlled by self-driving car software running AI algorithms fed by a network of sensors plus other data, and everything gets more complicated still. Fortunately, folks are thinking about exactly these kinds of problems.