An Integrated Intelligent Intersection Control System (IIICS) for Safety Improvement and Delay Minimization

The objectives of this research include both development and field test of the proposed integrated intelligent intersection control system (III-CS) that can concurrently address the safety and efficiency issues. Based on the dilemma zone protection system (DZPS), developed jointly by MDOT SHA and the research team, the proposed III-CS shall have the following key features: (1) Provide the time-varying advisory speed for approaching vehicles to smoothly progress through the target intersection so that they will neither be blocked by the residual queues from the last red phase, nor trapped in their dilemma zones during the yellow phase; (2) Execute the optimal green termination algorithm under the actuated control function to concurrently minimize the likelihood of rear-end collisions and the total traffic delay; and (3) Activate the all-red extension as needed to prevent the potential angled crashes. Such III-CS shall have the function to link together to constitute a real-time network monitoring system, allowing MDOT SHA’s responsible engineers to monitor their performance via the real-time detected traffic data (such as the distributions of speeds, headways, and flow rate), and also to conduct off-line safety analysis, including accident records, near-crash frequency, and impacts on the behaviors of driving populations over each intersection deployed with the proposed III-CS.