If some traffic sign does not allow overtaking, the
activation of the STS will be automatically disabled. The
”STS Enabled” rear sign is used to inform the overtaking
drivers that the vehicle in front of them is equipped with
the cooperative system. Hence, drivers closely approach the
rear of the vehicle to enable STS by pressing some contextaware
button on the steering wheel. Since the overtaking
vehicle also detects the ”STS Enabled” sign, the context for
the button is automatically set by sign recognition.