Drivers who like to check their email or do their make-up at traffic lights, beware.
General Motors, the largest U.S. auto manufacturer by sales, is preparing to launch the world's first mass-produced cars with eye- and head-tracking technology that can tell whether drivers are distracted, according to people with knowledge of the plans.
Seeing Machines, an Australian group listed in London, has signed an agreement with safety-goods maker Takata to supply GM with tracking devices for up to 500,000 vehicles over the next three to five years.
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The gadgets will start by measuring the rotation of the head so they can alert drivers if they are not spending enough time looking in certain areas such as the road ahead or the rear-view mirror.
"Safety doesn't sell cars - sexy sells cars," said Ken Kroeger, Seeing Machines' chief executive. "But once cameras are there, they can be expanded for other features and purposes."
GM said it could not comment on future product plans.
The car is the next frontier for using "smart" sensors to gather and crunch consumer data, along with the home and the workplace. The move is part of the escalating fight over who can use technology to make money from drivers - whether via dashboard apps, streaming music or even watching movies in self-driving cars.
"The key way for carmakers to differentiate themselves is how they enable the consumer and create and share content," said Thilo Koslowski, analyst at research group Gartner. "The user experience is an untapped opportunity that will crown the leader in this space."
Carmakers are boosting their digital offerings in response to fears tech groups will steal market share in the coming era of "connected cars". Automotive consultancy SBD estimates that the number of these vehicles will grow from 5.4 million in 2012 to 36 million in 2018, which would represent nearly a third of all cars expected to ship that year.
Mr Kroeger said Seeing Machine's equipment could eventually allow drivers to activate an app by simply looking at a certain point in the car and then touching a button on the steering-wheel. The devices could also be used to detect the identity of the driver as a guard against theft - or to stop a teenager using the family car after 10pm at night.
The technology raises significant privacy concerns over how manufacturers and insurers will store and handle the data, though Seeing Machines' devices will not keep or transmit the information, at least initially.
Insurance companies are already investing in telematics to monitor driver behavior using smartphones and "black boxes", which feed information back and adjust premiums according to that individual customer's use of the car.
Seeing Machines' devices involve cameras backed by algorithms that can identify features of drivers' faces, such as the rotation of the head and the frequency of eyelid blinks. It then imposes this information on a three-dimensional map of the interior of the car so it can tell to an accuracy of one degree what the driver is looking at.
The company is investing in technology that will be able to tell how hard a driver is thinking by monitoring the dilation of the pupils, and combines facial information with sensors for vital signs such as blood alcohol levels and heart rate.
The news comes as GM and Takata face controversy over their products. The carmaker is being investigated by the US Congress over its failure to recall millions of vehicles over more than a decade despite flaws in the ignition mechanism. Several manufacturers, including GM, Toyota and BMW, have also recalled thousands of cars because of a defect in Takata airbags.