Regulators in the US have said the artificial intelligence system that pilots a self-driving Google car could be considered the driver under federal law.

The National Highway Traffic Safety Administration told Google of its decision in a letter to the company, posted on the agency's website this week.

This decision is a major step towards ultimately winning approval for autonomous vehicles on the roads and means that they eventually won't need to legally have a licensed human driver on board.

Regulators in the US have said the artificial intelligence system that pilots a self-driving Google car (pictured) could be considered the driver under federal law. The National Highway Traffic Safety Administration told Google of its decision in a letter to the company, posted on the agency's website this week

On 12 November, Google's self-driving car unit on submitted a proposed design for a self-driving car that has 'no need for a human driver,' the letter to Google from National Highway Traffic Safety Administration Chief Counsel Paul Hemmersbaugh said.

'NHTSA will interpret 'driver' in the context of Google's described motor vehicle design as referring to the (self-driving system), and not to any of the vehicle occupants,' NHTSA's letter said.

'We agree with Google its (self-driving car) will not have a 'driver' in the traditional sense that vehicles have had drivers during the last more than one hundred years.'

Major automakers and technology companies such as Google are racing to develop and sell vehicles that can drive themselves at least part of the time.

All participants complain that state and federal safety rules are impeding testing and eventual deployment of such vehicles.

California has proposed draft rules requiring steering wheels and a licensed driver in all self-driving cars.

Karl Brauer, senior analyst for the Kelley Blue Book automotive research firm, said there were still significant legal questions surrounding autonomous vehicles.

This decision is a major step toward ultimately winning approval for autonomous vehicles on the roads and means that they eventually won't need to legally have a licensed human driver on board. The agency said it will interpret 'driver' in the context of Google's motor vehicle design and not to any of the vehicle occupants

But if 'NHTSA is prepared to name artificial intelligence as a viable alternative to human-controlled vehicles, it could substantially streamline the process of putting autonomous vehicles on the road,' he said.

GOOGLE'S SELF-DRIVING TRUCKS Google is developing both delivery drones and self driving cars - but a new patent reveals it is also building a smart delivery truck. The patent details plans for driverless trucks with lockers inside the cargo area and a pin code that give customers access to packages. Customers would receive a message when the vehicle is nearby - meaning the end of uncertainty over delivery times. The Autonomous Delivery Platform patent describes locker-like containers in the cargo area, which the receivers would type in a code or scan an NFC chip to claim their packages. Trucks would use sensors, video cameras and range-finding lasers to navigate the road and obstacles that may get in its path. Customers would receive a notification when the truck is about to arrive and if t is late, the truck will also let them know via text. Google has also suggested that receivers could pay for their packages when they receive them, turning the self-driving trucks into a vending machine on wheels. Advertisement

If the car's computer is the driver for legal purposes, then it clears the way for Google or automakers to design vehicle systems that communicate directly with the vehicle's artificial pilot.

In its response to Google, the federal agency offered its most comprehensive map yet of the legal obstacles to putting fully autonomous vehicles on the road.

It noted existing regulations requiring some auto safety equipment can not be waived immediately, including requirements for braking systems activated by foot control.

'The next question is whether and how Google could certify that the (self-driving system) meets a standard developed and designed to apply to a vehicle with a human driver,' NHTSA said.

Google is 'still evaluating' NHTSA's lengthy response, a company spokesperson said on Tuesday. Google executives have said they would likely partner with established automakers to build self-driving cars.

Google told NHTSA that the real danger is having auto safety features that could tempt humans to try to take control.

Google 'expresses concern that providing human occupants of the vehicle with mechanisms to control things like steering, acceleration, braking... could be detrimental to safety because the human occupants could attempt to override the (self-driving system's) decisions,' the NHTSA letter stated.

NHTSA's Hemmersbaugh added that federal regulations requiring equipment like steering wheels and brake pedals would have to be formally rewritten before Google could offer cars without those features.

Earlier this week, Google was awarded a patent for self-driving delivery trucks. The patent details plans for driverless trucks with lockers inside the cargo area and a code to give customers access to packages. They would receive a message when the truck is nearby, meaning the end of uncertainty over delivery times

For example, current federal rules require alerts on dashboards if tire pressure runs low.

NHTSA said a test would need to be created that shows the vehicle computer is informed of the problem. It also raised the question of whether humans in the vehicles should also be made aware.

In January, NHTSA said it may waive some vehicle safety rules to allow more driverless cars to operate on US roads as part of a broader effort to speed up development of self-driving vehicles.

Transportation Secretary Anthony Foxx said the administration may seek new legal authority to allow deployment of autonomous vehicles 'in large numbers,' when they are deemed safe, the department said.

The process of rewriting federal regulations governing the design, placement and operation of vehicle controls could take months or years.