ITSWC 2011 Adaptive traffic control – Modelling Performance Gains for Future Development Prepared 2 / Oct / 2011 By Steven Shaw

RTA and SCATS Roads and Traffic Authority of NSW (RTA) manages most motorways and arterial roads across NSW ~4000 SCATS signal controlled sites. SCATS is an area wide traffic management system developed by the RTA. SCATS implements adaptive traffic signal control also fixed time plans, if required. SCATS – 25 countries and 155 cities around the world.

Recent published SCATS papers 17 th World Congress on Intelligent Transport Systems 2010, Busan, Korea 1.“Introduction to experimental design when operating SCATS in simulation” Australasian Transport Research Forum 2011, Adelaide, Australia 2.“The evolution of the SCATS and the environment study” 3.“The SCATS and the environment study: introduction and preliminary results” 18 th World Congress on Intelligent Transport Systems 2011, Orlando, U.S.A. 4.“Experimental design when operating SCATS in simulation: a second iteration” 5.“Validating the realism and representation of SCATS when operating in simulation” 6.“SCATS and the environment study: an introduction”

SCATS and the environment study RTA has embarked on a comprehensive analysis study. Stimulus for study 2009 UN Climate Change Conference in Copenhagen, Denmark Landmark demonstration traffic performance production adaptive traffic control system / SCATS Unique in public (or commercial?) space to presenter’s knowledge

Stimulus for SatE study SCATS and the environment study “SatE study” Aim Demonstrate the transport, environmental and economic value that the operation of the SCATS installation provides to the people of NSW. Requirement rigorous and defensible study – in traffic simulation Required realistic and representative – to achieved real-world outcomes

How will the study / paper be used? Will support and influence strategic traffic / transport investments arguments for automated / adaptive traffic control arguments for SCATS arguments for investment in transport modelling quality transport modelling – techniques, strategies and investments traffic measurement – techniques, strategies and investments

What is the study methodology? Operate SCATS within a commercial traffic simulator - SCATSIM (AIMSUN, Commuter*, Q-Paramics*, S-Paramics, VISSIM) - ensures realistic operation - provisions representative operation 24 hour model (25/11/2009) start end model – lowest network intensity

Study scenarios – to show SCATS value 1.Base scenario adaptive traffic control operation (Masterlink mode) actual SCATS mode used calibrated to real-world traffic observations calibrating: detectors, electronic tag (inbound), bus GPS validated to real-world operation 2.Contrary scenario same conditions as base differs only by SCATS Fallback mode Fallback not used on day but would if comms failure occurred scenario not unlike a “sophisticated fixed time system”

SCATS screen shot SCATS screen-shot showing intersection Military Road / Spit Road intersection at Mosman.

Traffic simulator screen shot Commuter screen-shot showing pedestrians and buses.

Discussion of results of SatE study Preliminary results have shown dramatic traffic performance improvement over 24 hour model: 37% decrease in total travel time 21% decrease in total stops 6% decrease in total CO2 emissions 5% decrease in total NO emissions 10% decrease in total PM10 emissions Traffic performance > expectations. Environmental improvement = expectations (other published work). Adaptive control far superior to semi-adaptive, fixed time. Study defensibly demonstrates value that adaptive control provides cities.

SCATS future Ongoing improvements to SCATS will increase traffic performance. SatE study SCATSIM test bed will allow RTA to increase the performance of NSW SCATS by optimising SCATS configuration. SCATS flexibility empowers SCATS Engineer ability provisions “ITS innovation” that is limited only by available traffic measurements and traffic engineer’s imagination!

SCATS innovation In Sydney SCATS tracks buses in real-time using GPS SCATS prioritises buses for dynamic priority SCATS reschedules traffic signals for selected buses to match green times for bus arrivals – in real-time. Did you know: SCATS can use any detector types and detector locations? SCATS provides traffic control: intersections, ramp metering, etc. SCATS allows the traffic engineer to provide customised routines? Real SCATS and configuration can be operated within traffic simulation?

Thankyou