Cameras, lasers and sensors: Volvo reveals how its driverless cars will work
The automaker began its driverless car project in Gothenburg, Sweden, in 2014 and expects that driverless cars will be on Swedish motorways in two years' time.
"The key to success is combining sensors, computers and a chassis system in a clever way," said Erik Coelingh, a technical specialist at Volvo.
How will Volvo's driverless cars work
An autonomous car relies on precise geo-positioning. Volvo is testing a positioning system with 360 degree view of the car's surroundings using radars, cameras and laser sensors.
A tri-focal camera in the windscreen will detect imminent objects in front and beside the car. For a medium field of view, the camera can follow lane makers on the road. Objects further away, like debris will also be detectable.
The camera will help the car determine its distance from an object (a pedestrian or another unexpected hazard for example).In addition, there will be a multiple-beam laser scanner mounted on the front of the car below the air intake. This scanner has a very wide field of view with a range of 150 metres, to distinguish between objects like cars and debris.
The car also has medium-range radars mounted at each corner of the chassis to measure the distance to measure distance between guard rails and cars in the next lane.
An additional two long-range radars will be placed in the car bumper and twelve ultrasonic sensors will be placed around the car to identify objects close by.
Data storage
The car will be fitted with two independent computer systems for backup. If one fails the other will be able to stop the vehicle safely, Volvo said. Both the brake and steering system have backups too.
The cars are connected to a cloud service at the traffic authorities' control centre which sends the latest map data and traffic information to the car.
Cars will prompt drivers to take over from autopilot in the case of extreme weather or possible malfunction. If a driver does not respond, the car will assess a good place to stop.
Volvo said one of the biggest challenges was designing an autopilot feature that can deal with emergency situation where a driver cannot regain control.
This means that cars will drive on selected roads like motorways as there is little oncoming traffic, cyclists and pedestrians in Sweden. It hopes that by 2017, the public pilot in collaboration with legislators, transport authorities and the city of Gothenburg will begin.
Here in the UK, however, driverless car trials are not limited to designated roads, and driverless pods were given the green light on public roads this month.