Humans are the only ones putting the breaks on self-driving cars

According to the World Health Organisation’s Global Status Report on Road Safety 2013, the total number of road traffic deaths worldwide “remains unacceptably high”, with more than 1.24 million people killed each year. But worryingly, even in countries that do have the necessary laws in place – as is the case in the US – the number of road-related deaths each and every year still sits at just over 36,000. So when Google set out to design the world’s first fully autonomous vehicle, it wanted to create something that would “shoulder the entire burden of driving”.

In order to make that dream a reality, Google created a car that looks like something out of a child’s play set – but it is no toy. The tiny little prototype was designed around one thing: safety. It has sensors everywhere that allow it to remove all blind spots – something that is physically impossible for human drivers. These same sensors are capable of detecting objects from as far as 200 yards away, which is essential if the cars are to navigate their way through the hustle and bustle of city streets, packed public highways and tricky intersections. Not only that, but the prototype vehicle has been capped at 25mph, meaning that, if an accident does occur, the damage to it, and more importantly, to those in the other vehicles is dramatically reduced.

“On the inside, we’ve designed for learning, not luxury, so we’re light on creature comforts, but we’ll have two seats (with seat belts), a space for passengers’ belongings, buttons to start and stop, and a screen that shows the route—and that’s about it”, wrote Chris Urmson, Director of Google’s Self-Driving Car Project in a post on the company’s official blog.

On the road
Prior to letting its prototypes loose on the streets around Google’s headquarters in California, the team behind the pint-sized prototype put its software and sensors through its paces, attaching it to a fleet of Lexus RX450h SUVs.

“That fleet has logged nearly a million autonomous miles on the roads since we started the project, and recently has been self-driving about 10,000 miles a week”, wrote Urmson. “So the new prototypes already have lots of experience to draw on – in fact, it’s the equivalent of about 75 years of typical American adult driving experience.”

But in the event that Murphy’s Law should manage to manifest itself, all the prototype cars, as well as being capped at 25mph, have been equipped with a safety driver, whose job is to act as a failsafe should anything go wrong.

Prior to the cars embarking on the journey into the unknown, Urmson explained how he was “looking forward to learning how the community perceives and interacts with the vehicles”. But, according to the department’s monthly report for June this year, a couple of drivers chose to get up close and personal with the autonomous vehicles, resulting in traffic accidents.

On both occasions, however, the Google car (which was driving autonomously at the time) was not at fault. In fact, the other drivers simply didn’t pay enough attention, rear-ending Google’s automaton at low speed. Both incidents caused only minor damage to the cars’ rear bumpers and sensors. But, perhaps most importantly, there were no injuries reported in either accident.

“Given the time we’re spending on busy streets, we’ll inevitably be involved in collisions; sometimes it’s impossible to overcome the realities of speed and distance”, said the report. “Thousands of minor accidents happen every day on typical American streets, 94 percent of them involving human error, and as many as 55 percent of them go unreported.

“In the six years of our project, we’ve been involved in 14 minor accidents during more than 1.8 million miles of autonomous and manual driving combined. Not once was the self-driving car the cause of the accident.”

Human error
Some of the worst disasters and accidents in history can be attributed to simple human error. Which is why, when attempting to create something for which reliability and safety are of the utmost importance, the optimal design tends to be the one that can eliminate humans from the equation altogether. People only need to look at the statistics for road traffic accidents to see the inherent benefit of having robots behind the wheels, not humans.

The National Highway Traffic Safety Administration examined approximately 2.2 million car crashes across the US, with the intention of identifying the primary cause of each incident. In the report, researchers noted the “critical reason, which is the last event in the crash causal chain, was assigned to the driver in 94 percent of the crashes”. The remaining six percent was evenly attributed to vehicular failure, the environment (adverse weather conditions, etc), and what the report calls “unknown critical reasons”.

The two million crashes that arose as a result of driver error were then broken down into smaller categories: “Recognition error, which included driver’s inattention, internal and external distractions, and inadequate surveillance, was the most frequently assigned critical reason. Decision error such as driving too fast for conditions, too fast for the curve, false assumption of others’ actions, illegal manoeuvre and misjudgement of gap or others’ speed accounted for about 33 percent of the crashes. In about 11 percent of the crashes, the critical reason was performance error such as overcompensation, poor directional control, etc.”

It is easy to let the mind wander when out on the open road, but, nowadays, there are even more things that have the power to distract people. Easily the most dangerous of them all is the humble smartphone. The American Automobile Association even released a video entitled Distractions and Teen Driver Crashes to highlight the dangers of using mobile phones while driving.

All this information makes one thing abundantly clear: the biggest threat to human life on the road and the integration of autonomous cars into wider society is human error and people’s reluctance to forfeit their automotive autonomy.

Google’s driverless cars have managed to travel more than 1.8 million miles without causing an accident, underscoring the proficiency of their software and sensors to adequately anticipate the actions (and mistakes) of human motorists. Equally, however, it also shows that those same motorists are inept at reacting to the actions of autonomous vehicles.

In an interview with The Guardian, Anuj Pradhan, a behavioural scientist at the University of Michigan, explained how there is a lot of data being collected about how autonomous vehicles react to human motorists, but very little to the contrary. “We do not fully understand the human reaction where self-driving cars are involved”, he said. “It’s an important question that we haven’t started looking at yet. Self-driving cars may have a ‘better’ driving style but it may not be a human driving style, and that could affect how we predict or react to them.”

All or nothing
Google is not alone in its ambition to create a car capable of shouldering the burden of driving. Jaguar, Volvo, Nissan and Lexus are all tirelessly working away to bring their own iterations onto the market, which means that, sooner or later, and whether they like it or not, people will be forced to share the tarmac with robots.

One way to make the transition a little less painful (and hopefully reduce the number of collisions between man and robot) is to hide some of the driverless cars’ distinguishable features – mainly the abundance of sensors scattered on the top, tail, front and flanks of the vehicle. Pradhan even suggests coming up with a way of identifying the vehicles to encourage other drivers to exercise a little extra caution: “Should self-driving cars have a special marking so we can react accordingly? If I see a learner driver, I give it a little more following distance. Perhaps that’s how regular drivers would react to a self-driving car.”

No matter how the transition is managed, it will surely, as has been the case with practically every other groundbreaking piece of technology, generate much debate. Advocates of a world where people are free to text and drive will welcome them with open arms, while petrolheads who believe driving is best enjoyed with both hands firmly on the wheel will call them an abomination.

Such conflicting views about the future of motoring actually pose the biggest challenge to the proliferation of driverless cars. For the vehicles to be a true success, people must forgo their right to drive en masse.

So far, car designers have boasted about all the time that can be saved in a driverless world, but few have really shown what all those extra minutes could be spent on. Mercedes-Benz made a decent attempt of showcasing the more nuanced advantages to its driverless concept car, the F015 Luxury in Motion.

“Anyone who focuses solely on the technology has not yet grasped how autonomous driving will change our society”, said Dr Dieter Zetsche, Chairman of the Board of Management of Daimler and Head of Mercedes-Benz Cars in a statement on Mercedes’ website. “The car is growing beyond its role as a mere means of transport and will ultimately become a mobile living space.”

One of the most appealing things about driverless cars is improved safety, but that attribute is seriously undermined by the existence of other drivers on the road, who, as the data shows, find it difficult to read and react to the movements of their robotic counterparts. It is essential, therefore, that car manufacturers push home the wider benefits of driverless cars, as safety is simply not enough to tempt all motorists to forfeit their right to drive. The technology must be embraced wholeheartedly if it is to make a dent in the death toll.