Few big ideas have excited tech investors over the past few years as much as self-driving vehicles, and billions of dollars have been spent developing driverless cars, trucks and delivery vans.
But after the sharp acceleration in investment in US-based self-driving start-ups, from $282m in 2015 to $4.5bn last year, according researchers at CB Insights, entrepreneurs in the market are now preparing for a change of gear.
Of the dozens of companies to emerge over the past four years, a handful of autonomy pioneers has been able to secure such unprecedented sums of funding that some predict the rest will be unable to keep up.
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