Traffic Sign Recognition (TSR)

Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC

Traffic Sign Recognition (TSR) captures image data of the road scene. The Image Processing Module (IPMA), within the camera, infers speed limits implied and read from the scene.

The IPMA also obtains information about the current road from the navigation system through the High Speed (HS) Controller Area Network (CAN) comfort and chassis systems buses via the Body Control Module/Gateway Module (BCM/GWM) assembly. This data includes the current road speed limit, road type and country.

The IPMA combines the available speed limit information from both the navigation and vision systems, to provide a more accurate and consistently available speed limit value.

The speed limit value is sent from the IPMA to the BCM/GWM assembly using the HS CAN chassis systems bus. Then from the BCM/GWM assembly using the HS CAN comfort systems bus the vehicle speed limit value is sent to the Instrument Cluster (IC) and Head Up Display (HUD) which displays the information to the driver.

To indicate how recent the information is, the displayed sign fades away in a series of steps as the distance increases from the location of the sign. The driver can also use the system to provide a warning of speeding, by configuring the system to flash the speed limit sign in the display when the vehicle exceeds the displayed limit by a set amount.

Speed alert can be switched on and off, or the settings can be adjusted by the driver to display three different settings:

• Vehicle speed equals the detected speed limit.
• Vehicle speed is 5 mph (10 km/h) above the detected speed limit.
• Vehicle speed is 10 mph (20 km/h) above the detected speed limit.

Rain and snow speed limits are indicated, when applicable, as are towing speed limits, when a trailer is connected to the vehicle. Speed limit information from the navigation system is displayed for roads with no sign information.

If the navigation system is not available, or the off-road navigation is selected, the Traffic Sign Recognition (TSR) system will use the camera only, but cannot perform to full functionality.

The system can be switched on and off via the Instrument Cluster (IC) message center menu. The system will operate up to a maximum speed of 155 mph (250 km/h).

The performance of the Traffic Sign Recognition (TSR) system may also be affected in the following conditions:

• During adverse driving conditions, if the camera has impaired vision (reduced visibility, less than 0.6 miles (1 km), for example heavy fog, rain, snow, or soiled windshield.
• Signs are rotated greater than 15 degrees in pitch, yaw or roll, compared to the road surface.
• Concealed or covered sign information.
• Non-conforming road signs.
• Accuracy and validity of navigation data (i.e. up to date).
• Traveling in an area not covered by the navigation system.
• Driving in direct sunlight, leading to overexposure and reduction in contrast.
• Vehicle not in a supported country.

In the event of a system fault, the feature is suppressed until the fault is rectified. The driver is informed via an Instrument Cluster (IC) text message and warning symbol.