Unique critical movement identification algorithm for
advanced signal timing analysis
SIDRA was first developed implementing Dr Rahmi Akçelik’s well-known Research Report ARR 123 (Traffic Signals: Capacity and Timing Analysis). This was published by the Australian Road Research Board in 1981 - its influence continues today. The ARR 123 critical movement analysis method, which can handle simple to very complex phase sequences, is the core element of the timing analysis method in SIDRA INTERSECTION.
In this SIDRA INTERSECTION 9.1 display, circles represent phase change events and lines represent vehicle and pedestrian movements. The display shows the Movement IDs, Required Movement Times and the Critical Movements determined using a critical path method that considers overlap movements. This helps the user to understand how the interactions of movements in the phase sequence lead to the cycle time and phase times determined by the software.