Signaling¶
A vehicle's signals are encoded in an integer, each by one bit, encoding whether the according signal/... is on or off. Most signals are rather meant to be used by an external application. However, a few signals are computed in each step.
Computed Signals¶
The following signals are computed in each time step. The value set via TraCI is only retained for the current time step.
- VEH_SIGNAL_BRAKELIGHT: The brake light is set whenever the vehicle is standing (not stopped) or when the vehicle decelerates beyond a threshold value. The signal value is used by the vehicles when trying to avoid jamming on an intersection.
- VEH_SIGNAL_BLINKER_RIGHT and VEH_SIGNAL_BLINKER_LEFT: The blinker is activated in either of the following conditions
- The vehicle is about to take a turn at an intersection (activated 7 seconds before reaching the intersection)
- Either of the continuous lane-change models is active
- A desired lane change cannot be executed due to neighboring vehicles.
- a vehicle is about to stop for parking
- the vehicle is stopped on a lane that is not the rightmost usable lane (emergency blinkers on both sides are active)
- VEH_SIGNAL_EMERGENCY_BLUE: when switched on, a blinking blue light is shown in the GUI for vehicles with vClass="emergency" and shapeClass="emergency"
Defined Signals¶
The following table shows the defined signals.
| Name | Bit |
|---|---|
| VEH_SIGNAL_BLINKER_RIGHT | 0 |
| VEH_SIGNAL_BLINKER_LEFT | 1 |
| VEH_SIGNAL_BLINKER_EMERGENCY | 2 |
| VEH_SIGNAL_BRAKELIGHT | 3 |
| VEH_SIGNAL_FRONTLIGHT | 4 |
| VEH_SIGNAL_FOGLIGHT | 5 |
| VEH_SIGNAL_HIGHBEAM | 6 |
| VEH_SIGNAL_BACKDRIVE | 7 |
| VEH_SIGNAL_WIPER | 8 |
| VEH_SIGNAL_DOOR_OPEN_LEFT | 9 |
| VEH_SIGNAL_DOOR_OPEN_RIGHT | 10 |
| VEH_SIGNAL_EMERGENCY_BLUE | 11 |
| VEH_SIGNAL_EMERGENCY_RED | 12 |
| VEH_SIGNAL_EMERGENCY_YELLOW | 13 |
Note
Sending a negative signal value immediately resets all signals to their computed values.