The promise of autonomous cars has no doubt been an exciting and intoxicating one for technophiles everywhere, not to mention those who see driving as a chore that must be endured, rather than enjoyed. There's no shortage of autonomy evangelists - Tesla CEO Elon Musk is a famous example, Ford reckons it will have its first truly self-driving car ready by 2021 and BMW and Mercedes have similar timelines - while ridesharing companies and Silicon Valley tech giants like Uber and Google are also bullish on fully-autonomous vehicles. And why wouldn't they be? Without a driver taking a cut of fares, profit margins for those businesses would explode, while also giving the public cheaper rides and potentially freeing them from the financial burden of owning a car. But according to one of the world's biggest manufacturers of the advanced sensors that make autonomous cars possible, the utopian vision of completely hands-off, point-to-point driving is highly unlikely for the foreseeable.