Configure Built-in Traffic Flow

Select Traffic Flow from the Case Resource Library and drag it into the Case Editor workspace. Configure parameters in the properties panel on the right.

Traffic flow-based testing can automatically generate traffic participants in the virtual scene, simulating complex real-world traffic conditions through a traffic behavior model.

• Vehicle Types: Users can select or deselect vehicle types based on category and thumbnail. For each category, a behavior slider allows adjustment of vehicle behavior strategy between conservative, moderate, and aggressive.
• Vehicle Type Ratio: Users can flexibly adjust the proportion of different vehicle types to match the target simulation environment (e.g., suburban, urban).
• Element Density: Users can set the traffic congestion level in the virtual scene for different element types (vehicles, pedestrians, bicycles) using the traffic flow slider.

SUMO Configuration

The built-in traffic flow module in SimOne is developed based on SUMO. Additional parameter adjustments can be made by modifying configuration files.

Configuration Files

Config Type	Location	Description
Global Config	SUMO\config\sumoConfig.json	Global configuration affecting all maps
Map Config	SUMO\	Private configuration for the current map
Map Config	SUMO\	SUMO runtime configuration
Map Config	SUMO\	SUMO vehicle type configuration

Global Configuration

SUMO\config\sumoConfig.json

Parameter	Default	Description
SUMOIP	127.0.0.1	SUMO service IP address
SUMOPort	58289	SUMO service port
StepLength	0.03	Simulation step length
SUMOWindowsExe	sumo.exe	SUMO executable name on Windows
SUMOLinuxExe	sumo	SUMO executable name on Linux
HasMainVehicle	TRUE	Whether an Ego Vehicle is present
NewVehicleForbiddenRange	200	Spawn exclusion radius around the Ego Vehicle (meters) — SUMO vehicles will not spawn within this range
DensityCoefficient	1	Density coefficient
EnablePrediction	FALSE	Enable SUMO trajectory prediction (10 prediction points)

Map Configuration

SUMO\

Parameter	Default	Description
MaxVehicleNumber	No limit	Maximum number of SUMO vehicles
PreRunDuration	90	Wait time (seconds) for vehicle loading. If set below 0, the default value of 90 is used
LaneChangeAggressive	FALSE	Enable vehicle following diversity
VehicleRange	200	SUMO vehicle subscription range (meters) — vehicles within this range of the Ego Vehicle are subscribed; those outside are ignored
PersonRange	100	SUMO pedestrian subscription range (meters)
EdgeRange	10	Edge subscription range
SkippedFrameCount	10	Number of frames to skip at the start of simulation
CreateEvenTrafficflowAtStart	FALSE	Generate uniform traffic flow at simulation start
TimeToTeleport	0	How long a vehicle may wait before being teleported; defaults to 300. Non-positive values disable teleporting
VehicleDensityPerMap	1	Vehicle density setting for the current map; supplements the DensityCoefficient setting

SUMO\

Parameter	Default	Description
gui-message	TRUE	Enable SUMO-GUI log output. Set to false if the SUMO GUI becomes unresponsive
pedestrian.behavior	onlyonce	Pedestrian behavior; valid values: round, onlyonce
pedestrian.max-num		Maximum number of pedestrians
pedestrian.frozen		Enable pedestrian freezing — SUMO freezes pedestrians outside a certain range of the Ego Vehicle to improve performance
pedestrian.frozen-range		Pedestrian freeze range; only effective when pedestrian.frozen value="true"
bike.behavior	onlyonce	Bicycle behavior; valid values: round, onlyonce
bike.max-num		Maximum number of bicycles
lane.bike-num	3	Maximum number of bicycles per lane

SUMO\

Parameter	Description
length, width, height	Vehicle dimensions
maxSpeed	Maximum vehicle speed (m/s)
accel	Vehicle acceleration
decel	Vehicle deceleration
minGap	Minimum gap between vehicles (m)