Applications and driving behavior parameters of lane changing

Vissim distinguishes between the following lane changes:

• Necessary lane changes in order to reach the next connector of a route. These are triggered by:

• the vehicle route
• in the context of dynamic assignment by the path
• when a desired lane is set via the COM interface

For a necessary lane change, the driving behavior parameters contain the maximum acceptable deceleration for the lane changing vehicle and its trailing vehicle on the new lane. The deceleration depends on the distance to the emergency stop distance of the next route connector.

• Free lane changes, if more space is available on the new lane or if longer driving at the desired speed is required:

When a free lane change is performed, Vissim checks whether both desired safety distances are maintained on the new lane:

• the desired safety distance of the trailing vehicle to the lane changing vehicle
• the desired safety distance of the lane changing vehicle to its preceding vehicle

The safety distance reduction factor is applied to both desired safety distances.

By default, a lane change takes 3 seconds.

You cannot change the degree of "aggressiveness" for free lane changes. You can, however, influence free lane change by changing the safety distance. You set the safety distance values in the model parameters of the car following model (Editing the driving behavior parameter car following model).

In both cases of lane change, upstream and downstream, the Min. clearance must be respected (Editing the driving behavior parameter Lane change behavior).

When deciding on a lane change to overtake a slow vehicle, a vehicle considers its own current maximum speed depending on the lane change behavior:

• when the lane change behavior Free lane selection is selected
• when the lane change behavior Slow lane rule, Fast lane rule is selected and the preceding vehicle or the neighboring vehicle is driving slower than 60 km/h and therefore the rule is ignored

Since the maximum speed is defined by the maximum acceleration and the current gradient, taking the maximum speed into account prevents HGVs from starting to overtake on gradients, for example, without being able to overtake because they cannot reach their desired speed.

In 2D animation, a current change of lanes, as well as the desire to change lanes is visualized via a small red line to the right or left of the vehicle (representing the turn signal), from the defined Lane change distance on. In 3D animation, a current lane change and the desire to change lanes is shown via a turn signal, if this is defined for the 3D model of the vehicle.