Drowsy Driver Detection

Adaptive Cruise Control (ACC/DASM) Radar 

The ACC/DASM radar is mounted to a bracket located on the front bumper beam the behind the lower grille. The ACC/DASM radar and bracket are replaced together as a unit.

Body Control Module (BCM) 

The BCM performs the gateway capability between both the CAN-Interior High Speed (CAN-IHS) and CAN-Chassis (CAN-C).

Instrument Panel Cluster (IPC) 

The IPC is used to display Drowsy Driver Detection (DDD) system visual and audio event alerts to the driver. The IPC will also store DDD event alerts in memory.

The DDD system is set to be available when the following conditions are met:

• No DDD system faults are present
• Vehicle speed does not exceed 200 km/h (124 mph)

When criteria is met the ACC/DASM radar transmits a Controller Area Network (CAN) message indicating that the system is actively monitoring for DDD.

Once the DDD system is available, the ACC/DASM Radar monitors the steering wheel inputs to create a range of acceptable tolerances. Those inputs are:

• Counterclockwise positive angle
• Steering speed value

The ACC/DASM radar also receives the following signals as part of the DDD algorithm:

• Accelerator pedal position
• Brake pedal status, brake and driver brake pedal torque signals
• External lights and headlamp switch signals (i.e. hazard, fog, switch positions)
• Turn signal indicators
• Steering wheel switch commands
• Engine speed signals
• Engine status signal
• Cruise control (normal or adaptive) state
• Wheel speed
• Active Lane Management (ALM) steering control request
• Steering column torque signal

Other inputs used:

• ALM information from the camera to detect lane crossing
• Detection of a jerk in the steering wheel movement that is outside of the tolerance band that has been mapped by the DDD system at the beginning of the ignition cycle

When using the signals and systems to determine the DDD algorithm, when there is a suspected instance of a drowsy driver the DDD system will trigger an alert. The alert will be a visual and an audible alert. The ACC/DASM radar is in control of the activation and deactivation of these warnings by transmitting a signal to alert the driver. This signal will be continuously transmitted until the ACC/DASM radar receives signal from the steering wheel switch command. This command is initiated by the customer selected "OK" on the hard switch. The IPC will then activate a drowsiness detected stored message.

Whenever there is a fault detected in any of the systems and inputs used by the DDD algorithm, the ACC/DASM radar will disable the DDD system, set a Diagnostic Trouble Code (DTC) and then alert the driver that the system is not available via a message on the IPC.