SCOOT Real-Time Adaptive Control in a CORSIM Simulation Environment

The manner in which the adaptive signal control system SCOOT (Split, Cycle, Offset Optimization Technique) has been connected to the CORSIM traffic simulation model is described. To demonstrate the connection, CORSIM simulates the traffic activity of a six-node traffic network under SCOOT’s adaptive traffic signal control. CORSIM’s “virtual detectors” provide the necessary data for SCOOT optimization in real time. In a completed loop, the optimized signal timing is then communicated from SCOOT to CORSIM, which implements the timing and updates the traffic simulation. This means that SCOOT is now functioning in an entirely simulated environment. A comparison of delay and travel time is presented for a six-intersection street network under SCOOT control and under fixed-time area control optimized with TRANSYT-7F. The results show reductions in delay and numbers of stops of 20 to 30 percent. Previously, the measurement of the benefit of adaptive control has been limited to evaluations of systems after implementation. It is shown how SCOOT can now be evaluated under various network traffic conditions in a simulation environment and tested on a specific city network to evaluate the benefits before capital costs are committed.