Published November 11, 2022
The Department for Infrastructure and Transport in South Australia developed the Tactical Adelaide Model (known as TAM) to provide a brand-new industry paradigm via a maintained and governed multi-modal transportation operational assessment model.
Transport modelling is a crucial factor in supporting urban design and investment decisions, examining the impact of different land use planning decisions and managing traffic control systems.
While project-specific models are valuable tools, they are frequently developed in isolation from one another and end up differing greatly in shape, size, platform, and configuration. Attempts to create large-scale models by stitching together these project models result in patchwork solutions that are not fit for purpose for wider-scale evaluations and policy making.
The Department for Infrastructure and Transport (DIT) in South Australia wanted to solve these issues by developing a single, unified, consistent large-scale modelling framework; the result is the Tactical Adelaide Model (TAM), led by Transport Analytics in partnership with Aimsun.
Delivered in May 2022, TAM is the heart of DIT’s modelling framework and has already proven invaluable in supporting network planning decisions. The TAM modelling framework covers the five most critical use cases:
The default operation of the whole-city modelling framework is at the mesoscopic level of detail, which is dynamic in nature but at a mid-level of granularity to keep computational effort as low as possible and prioritize speed and agility. However, in cases where simulation-based responses might need more detail, such as say, a heavily congested roundabout or junction, Aimsun Next is able provide pockets of microscopic level simulation, zooming into the behaviour of individual road users. These microscopic pockets of simulation would only be considered for special project-based applications or as further enhancements and could be maintained on an on or off basis due to Aimsun’s highly flexible, hybrid model structure.
DIT’s innovative formation of a partnership led by an agile delivery framework and working to a set of overarching principles was an industry first. This approach has proved to be instrumental in delivering the accuracy and robustness of TAM. The solution’s scope has already delivered operational-level project results at a fraction of the time and resources used previously.
DIT will use TAM to evaluate the impact of new transport modes, disruptive technologies, Mobility-as-a-Service and environmental impacts/management, which will change the network planning and operations on a metropolitan level. This cannot be considered in project models or in isolation. Therefore, the TAM framework will be the integrated platform to assess feasibility and plan/manage government and industry initiatives.
DIT has committed to maintaining TAM, keeping it up to date and relevant to the stakeholders and industry partners. The maintenance regime will include annual updates, alignment with the newest census and household travel survey information, new data sources, product improvement and software version control.
TAM will also be updated with the latest committed and funded projects to ensure consistency in model outputs. TAM will be open to stakeholders and consultants, offering transparency and a level playing field. Quality Management processes will accompany the TAM Guidelines to ensure the work done using the solution is consistent and relevant to the use case.
TAM will be a vital platform for South Australia in developing policy and strategy for the challenges that face all state agencies worldwide: transport business cases and scenarios for connected and autonomous vehicles, cooperative ITS, low or zero-emission vehicles and air quality management.
Future TAM enhancements extend well beyond the current framework and will include cloud-based model development and implementation. The team will also be refining the approach to model governance, version control, sub-area extraction, research initiatives from academia, project modelling integration, modelling guidelines, and of course, a completely seamless data flow between the existing strategic model (known as the Strategic Adelaide Model or SAM) and TAM.
Other plans in the pipeline for TAM include dynamic simulation for emerging and future transportation technologies and disruptors, electric vehicles and infrastructure, connected and autonomous vehicles, traffic management centre and operational insights, and emission/air dispersion modelling.
At present, TAM’s forecasting horizon stretches to the year 2041, which will enable DIT to plan and safeguard real-world mobility outcomes for the community of Greater Adelaide.
DIT considers TAM an industry-leading initiative and a fundamental platform for developing future transport strategies in South Australia.
The TAM initiative had to overcome significant challenges in the form of the magnitude of the modelling scope and the departure from industry norms. These challenges necessitated a highly collaborative approach between DIT and Aimsun but in the end it paid off: the solution not only met but exceeded the calibration criteria and received extremely positive industry feedback.
TAM will be a fundamental component in supporting DIT’s vision for making its multimodal transport system more sustainable, efficient, safe, and accessible.
Published in Infrastructure Magazine, Australia, Issue 25, November 2022