Aimsun Next replaces the physical vehicle detection system that is required for STREAMS’ operation by simulating the traffic detection data instead. It also receives any traffic management actions shown in the overhead gantries (known as Lane Use Message Signs or LUMS) and ramp metering values in real time from STREAMS. Driver behaviour is updated accordingly, based on the LUMS display.

A key feature of this interface is the ability to repeat scenarios many times, as operators can re-run any traffic incident over and over again and try out different strategies. The real-time traffic animation mimics the traffic monitoring cameras with some added benefits such as zooming and following the traffic. By trying different solutions within the simulation, the operator will already have a good idea of what to do when faced with a similar situation in real life.

The training allows operators to have hands-on, experience-based training, bypassing the process of learning by trial and error on real roads.

The Toolkit

In one example, the operators were given a simulated incident and lane closure on State Route 2, south of Perth’s Central Business District. The operator had the tools within the STREAMS software to adjust the speed limits, which would then show up in the overhead LUMS gantries. The operators could also inform the upstream traffic about the incident and ask them to avoid any affected lane.

 The Aimsun Next model received the LUMS changes and updated driver behaviour to reflect those changes. The operator was able to watch how the traffic responded, even down to a simulation of an individual vehicle. They could see whether jams built up, the effect on other roads and intersections, and how the traffic cleared once it had passed the road closure. Once they had learned from this, they could go back to the beginning and rerun the scenario, trying out different ways of managing it until they became confident to manage a similar incident in the real world in the most efficient and effective way.

Real time

The integration between Aimsun Next and STREAMS is set up in the Amazon Web Services (AWS) environment, which provides easy access to both systems remotely. All the communications between Aimsun Next and STREAMS happens in real time, meaning the operators can practice as though this were a real event happening right now.

The training allows operators to have hands-on, experience-based training, bypassing the process of learning by trial and error on real roads.

 This tool also provides an excellent opportunity for the road safety team to test and improve their recovery plan in the event of any incident where emergency vehicles might require access. They can test how fast first responders can access the incident location and how STREAMS can help to minimise the delay. The simulation can test the limit of the current facility by changing the location/severity/response time of incident. The interface can also be deployed to plan roadworks and other events where lane restrictions would be needed. 

No longer do operators have to wait for weeks or months on shift before being faced with a new or unusual edge scenario, and their expertise in turn improves the user experience on the roads.

This system has been set up with a specific piece of software in a specific place, STREAMS at Main Roads WA, but the concept could be used anywhere, with any piece of traffic management software. By learning in a highly realistic simulated environment, operators can gain expertise with new systems and software while the real world outside flows as normal.