The UC-win/Road has a variety of traffic simulation functions. In this topic, we introduce its advanced settings and control settings related to the traffic flow simulation.

Change the traffic volume and speed by lane

The amount of traffic can be specified by the number of vehicles generated per hour on each road. In addition, the amount of traffic, speed, and traffic profile (ratio of vehicle type) can be set by lane too. This setting allows you to reproduce traffic situations according to each road, for example, you can make differences in congestion by lane, reproduce bus lanes, or run many trucks on the left lane and faster vehicles on the passing lane on highway.

Go to "Edit" tab - "Traffic" on the menu and click "Generator" to open "Traffic Generator List" screen.

Select an object traffic flow and click "Edit" to open "Traffic Generator Editor" screen. Click [+] mark and lanes are displayed. You can configure the volume of traffic, initial speed, and profile for each lane.

Specify the traveling direction of specific vehicles

Normally, vehicles traveling on roads created in the UC-win/Road change directions at intersections and branches at random. This means the same vehicle does not always go to the same direction when repeating simulations. If you want to see an autonomous driving on a specific route or to make a certain vehicle go to a fixed route in scenarios, please add a vehicle group and fix the route.

This setting allows you to make a certain vehicle go to a specific direction. For example, you can make a scenario with an emergency vehicle coming from behind overtakes the vehicle in operation and turns left at the next intersection.

First, create a vehicle group and a profile for the specified vehicle. On the menu, click "Vehicle Groups" in "Traffic" in "Edit" tab to open "Vehicle Group Editor" screen. In "Vehicle groups", click "New..." and create a new vehicle group (emergency vehicle in the image). In "Performance profiles", create a new profile by clicking "New..." or copying the profile of other vehicles. In the image, the performance profile named "Ambulance" is added.

Make sure that only "Ambulance" is checked in the performance profile when "Emergency vehicle" is selected in the vehicle group, and "Ambulance" is not checked for other vehicle groups. Select any sound profile for "Ambulance".

Next, assign the created performance profile. Open the model editor of the vehicle model to be controlled, and change the vehicle performance profile to the newly created profile (Ambulance here) in "Vehicle editor" tab. If you want to control one vehicle among several same type vehicles like passenger car, create the controlled model by copying the normal vehicle model and use a different profile between randomly traveling models and the controlled model.

After finishing the vehicle setting, decide a travel route. Left click and right click an intersection on the route and open "Intersection Editor" screen. You can specify the direction of travel for each vehicle group in "Drive paths" tab. To make "Emergency vehicle" turn left in the image below, click the arrows on the routes, check "Emergency vehicle" group in the table on the right, enter a value only in the weight of left direction and 0 in the other weight fields. By entering a weight value in only one field like this, the vehicle with its profile checked moves only in the decided direction.

Setting of intersection where left turns on red are allowed

Vehicles are controlled to obey traffic lights at intersections, but there are intersections where vehicles can turn left on red signal in the real world. This type of intersections can be reproduced by setting vehicles not to obey the signal on a specific route on the intersection edit screen. This setting is editable only when opening the edit window from the plan view. In "Traffic Controls" tab on the edit screen, click an entrance point (green bar) at the edge of the drive path where you want to allow the left turn on red signal. The selected route is displayed in green. Put a check in "Override" in "Current Drivepath" and select "Uncontrolled", and vehicles running on this route will not obey the traffic light. If you select "Stop" instead of "Uncontrolled", vehicles will always make a temporal stop at the stop point, and if you select "Give way", vehicles will always give way when another vehicle comes.

Fig.9 Turn left on red is allowed.