Inputs, routing decisions and routes guide pedestrians

When pedestrians are added to the network via pedestrian inputs, they are guided to their destination via routes obtained through routing decisions.

Using pedestrian inputs to add pedestrians to a network

You can define pedestrian inputs on pedestrian areas or have them automatically generated from an OD matrix. In doing so, you also generate routing decisions and routes to destinations (Pedestrian OD matrices).

• If you define pedestrian inputs for pedestrian areas, you also need to define routing decisions for pedestrians.
• At least one route per pedestrian is required that is included in a time interval of the pedestrian input and belongs to the pedestrian composition of the input. This is automatically the case, when for the routing decision, you specify the attribute AllPedTypes (All pedestrian types). However, if you choose a pedestrian class that only includes some of the pedestrian types, a pedestrian type might be used at the pedestrian input, but no route will be defined for it. In this case, the simulation would be canceled and an error message displayed. A routing decision, for which the relative volumes of all routes are set to NULL for a time interval, is treated as if it did not exist.
• A routing decision assigns each newly generated pedestrian a route that has been defined for his pedestrian type or pedestrian class. If there is more than one route for a specific pedestrian type, a route is chosen randomly according to the relative volumes of individual routes.
• Each route leads via a sequence of areas and ramps, which form the route locations.

Strategic routes guide pedestrians throughout the network

• A pedestrian always walks towards his next routing point.
• When a pedestrian reaches a route location which has been assigned a time distribution in the attribute TmDistr (Time Distribution), he waits for the period defined.
• If this was not the pedestrian's last route location, he walks on to the next route location.
• However, if this was the last route location of his route and if the area of the route location contains a routing decision with routes for this pedestrian type or class, he is assigned a new route that he will continue to follow.
• If there is no route for the pedestrian, he is removed from the network.
• If the area with the last route location contains a pedestrian input, the pedestrian is removed from the route, as it is assumed that routing decisions on areas that contain a pedestrian input are specifically meant for new pedestrians coming from this input.
• If the last route location lies in an area that has been assigned the attribute PTUsage > Waiting area, the pedestrian remains in the network, if there is no routing decision for this area. He waits for a suitable public transport vehicle to board (Attributes of areas) and (Modeling pedestrians as PT passengers).
• There may be several "tactical" options for pedestrians to get from one route location to the next. For example, they can pass by obstacles, keeping left or right or use stairways and ramps to get to their destination. Moreover, pedestrians must be able to sidestep each other. Viswalk automatically performs the calculations and makes the decisions for such actions during the simulation. In multi-level scenarios, Viswalk internally computes a routing graph. The routing graph consists of the route locations you defined and additionally contains a route location for both ends of each stairway and ramp on the route. The routing graph thus includes relevant information on all routing variants that lead via the same level or via different levels that are connected via stairways or ramps. Based on the routing graph, Viswalk determines the shortest path between two route locations. The shortest path is used for the pedestrian's tactic movement. In Viswalk, pedestrians prefer routes without stairways or ramps, even if these are shorter. If instead you would like pedestrians to use stairways or ramps, place your route locations on the desired ramps.

Requirements for assigning routing decisions

The following requirements must be fulfilled for a pedestrian to be assigned a new route.

• A routing decision has been defined for this area.
• A routing decision becomes effective for its pedestrian type through class dependency.
• The pedestrian currently has no route. The might be due to the following:
• The pedestrian was newly generated.
• In this time step, the pedestrian has reached the final route location of his current or previous route.
• The pedestrian has alighted from a public transport vehicle and is entering an area that has been assigned the attribute PTUsage > Platform edge (Attributes of areas) and (Modeling pedestrians as PT passengers)..