Arterial Management

STREAMS UTC optimises the routes, intersection groups, intersections, and movements within a road network to ensure they operate in synergy and enhance traffic flow. It is a dynamic system that responds to changes in current traffic conditions through the use of real-time data and application of smart algorithms to make changes to on-road traffic operations. With almost 50 years of continuous development, STREAMS UTC improves safety and reduces congestion.

Through integration of STREAMS UTC into the STREAMS ITS Platform, STREAMS Smart Motorways is able to send requests to STREAMS UTC regarding intersections situated near the end of motorway off-ramps. STREAMS Smart Motorways detects when it is likely that a queue on a motorway off-ramp could queue onto the motorway and requests STREAMS UTC provide a longer green cycle time to clear the queue. Without the ability to communicate between systems, and due to a general lack of integration of other UTCs with sophisticated motorway management systems, busy off-ramps continue to dangerously queue traffic back onto motorways, significantly increasing the risk of dangerous, high speed accidents.

Ability to holistically manage traffic across an entire network

STREAMS UTC, as part of the ITS Platform STREAMS can manage and optimise traffic across an entire road network.

Modern communications networks

As well as supporting traditional networks, STREAMS can use modern communications networks including xDSL, fibre and wireless technologies. These links can be shared with other ITS equipment (such as CCTV) without impacting on intersection operations.

Control hierarchy

STREAMS manages traffic signal networks by organising controlled entities into the following hierarchy:

• Routes
• Intersection groups
• Intersections
• Movements

The control parameters are adjusted continuously in real time to optimise coordination and minimise delay.

Coordination policy

Traffic engineers nominate the required coordination policy to influence the coordination along each route.
The three options are:

• Maximise coordination: the route is coordinated from end-to-end for peak hour and other universal scenarios.
• Minimise delay: the route breaks into smaller segments to optimise coordination for local traffic conditions.
• Balanced: smaller segments will attempt to group and run together to strike an optimal balance between maximising coordination and minimising delays.
• Intersection groups are merged and diverged again to support the current coordination route segments.

The optimised plan for the prevailing traffic conditions is chosen to minimise delays. Vehicle and pedestrian movement demands are calculated every cycle and the optimal plan is chosen to ensure the efficient allocation of capacity for the current demands.

Performance measurement and reporting

STREAMS continuously measures system performance to optimise current operations and provide historical reports, including a full range of reports for operators and engineers. Both real-time and historical reports can be generated for individual intersections, intersection groups, and routes.

Interface to third-party UTC

An attribute of STREAMS is its ability to interface with other urban traffic control systems such as SCATS^®. Through a customised interface, customers can realise the benefits of an integrated ITS platform while still using their existing system.

The STREAMS interface to SCATS^® adds significant value to SCATS^® software installations to maximise transport road network efficiency. The SCATS^® interface delivers immediate user benefits even prior to integrating with other devices or systems. It requires minimal setup and provides sophisticated automation of the creation of SCATS^® configuration data. With a STREAMS system in place that can meet all of a customer’s ITS requirements, operators can see immediate benefits while engineers migrate legacy equipment such as variable message signs to the new platform.