Using weight distributions

The weight of vehicles of category HGV is defined via weight distributions. Weight distributions are irrelevant for other vehicle categories.

You need to assign each vehicle type to a vehicle category. From the weight and power distribution data assigned, Vissim randomly selects a value for each vehicle with a vehicle type under vehicle category HGV. The weight and power distribution values are independent from each other. This means Vissim may assign high power to a low-weight vehicle. Using the weight and power data, Vissim calculates the specific power (in kW/t). The specific power is limited to a range between 7 and 30 kW/t, so that no unrealistic weight/power combinations are created. If a value < 7 kW/t is calculated, the specific power is set to 7 kW/t. For values exceeding 30 kW/t, the specific power is set to 30 kW/t.

The specific power has an impact on acceleration and deceleration behavior (Using acceleration and deceleration functions). This is particularly important for links with gradients. Using the specific power, Vissim calculates the percentile used to select the relevant acceleration curve from the distribution of acceleration functions.

Weight distributions are defined independently from the vehicle type.

The probability increases up to the maximum weight defined, reaching the value 1.

Note: Vissim provides typical default values for desired distributions.