An artificial vision system intended as a safety backup for drivers is under development by the National Information and Communications Technology Australia (NICTA) lab in Canberra.

The Driver Assistance System (DAS) optically checks roadside signs and alerts the driver if there is no response to critical signs, such as those indicating speed limits.

Three cameras provide the primary inputs. One mounted behind the rearview mirror scans the road ahead. Two cameras fitted to the corners of the dashboard generate a stereo image of the driver’s gaze to monitor where he or she is looking.

This information is interpreted by software in the DAS’s central control unit, which is programmed with a database of all known road signs. A further input comes from the speedometer.

The road “view,” the driver’s awareness of same and vehicle speed thus are monitored and combined in a closed loop to support the driver in making decisions. The DAS’s automated sign recognition software checks for any lapses in attention due to distractions, such as cell phoning, or some other lack of concentration.

Every scanned sign is compared with the DAS database of stored images of symmetrical shapes, including octagons, triangles, diamonds and circles.

If there is a speed limit, for example, that the driver hasn’t acknowledged – perhaps the brakes aren’t applied – the system sounds a warning. Stop and yield signs also are monitored, with the system taking into account if the driver is slowing down. These key signs also can trigger the alert.

Less critical signs, such as directional information at road intersections, are ignored, but could appear on a discrete visual display the driver can view when convenient – if trying to determine if the proper route was followed, for example.

Robert Bosch GmbH recently showed similar technology for a sign-recognition system. (See related story: Bosch’s Solution For Speeding)

The development of DAS is an ongoing safety project at NICTA.