A critical review of Austroads Report AP-R621-20
Revised version published as Austroads Report AP-R647-21 “Management of Traffic Modelling Processes and Applications”
Diverse capabilities of software packages
Most software packages listed in the Austroads report model categorisation table have capabilities for modelling intersections and networks, use a mixture of analytical and simulation modelling techniques, and involve macroscopic, mesoscopic and microscopic levels of detail. Therefore, the relationship between model categories and software packages is a complicated one. Forcing groups of software packages into boxes in an inconsistent model category scheme creates misleading impressions.
Assessment of software packages
It is recommended that the listing of software packages is removed from the table of model categorisation. A separate table such as the one shown below could be prepared for the assessment of applicable model categories and key model features applying to individual software packages. This would help with the selection of software packages for the specific purposes of traffic and transport modelling projects. Consultation with software developers is recommended in developing such a table. Such an assessment table should be updated regularly as the modelling capabilities of the software packages extend continually.
Table: Proposed table for assessment of software packages
Software | SIDRA | Software X | Software Y | |
Model Categories | ||||
Model Type | Strategic Transport Model | x | ||
Large Area Traffic Model | ✓ [1] | |||
Intersection and Small Area Traffic Model | ✓ | |||
Model Level of Detail | Macroscopic | x | ||
Mesoscopic | ✓ | |||
Microscopic | ✓ | |||
Modelling Technique | Simulation | ✓ [2] | ||
Analytical | ✓ | |||
Key Model Features | ||||
Road Geometry | Lane based | ✓ | ||
Link / Lane Group based | x | |||
Approach based | x | |||
Vehicle Paths | Acceleration - deceleration | ✓ | ||
Fuel, emissions, operating cost | ✓ | |||
Four-mode elemental | ✓ [3] | |||
Three-mode elemental | x [3] | |||
Pedestrians | Signalised crossings | ✓ | ||
Unsignalised crossings | ✓ | |||
Traffic Control | Signals | ✓ | ||
Roundabouts | ✓ | |||
Give-way or stop sign control | ✓ | |||
Uninterrupted flows | ✓ | |||
Capacity Model (Capability to estimate key model parameters) | Saturation flow (Signals) | ✓ | ||
Follow-up headway and | ✓ | |||
Follow-up headway and | ✓ | |||
Network Model (Link-based and lane-based models) | Signal platoons | ✓ | ||
Capacity constraint | ✓ | |||
Queue spillback (exit blockage) | ✓ | |||
Midblock lane changes | ✓ | |||
Midblock inflow and outflow | ✓ | |||
Network signal timing | ✓ | |||
Demand Modelling | Peak Flow Factor | ✓ | ||
Variable demand modelling | x[4] | |||
Traffic Demand Estimation | Traffic assignment | x[4] | ||
OD matrix estimation | x[4] | |||
- Up to 50 intersections.
- Includes signal platoon simulation (second-by-second lane-based movement of platoons) as a mesoscopic simulation feature.
- Four-mode elemental vs three-mode elemental model of drive cycles.
- Under development