Logic-Based Traffic Flow Control for Ramp Metering and Variable Speed Limits—Part 1: Controller

This paper proposes a Logic-Based Traffic Flow Control algorithm (LB-TFC) for integrated control of Ramp Metering (RM) installations and Variable Speed Limits (VSLs) in order to reduce traffic jams created at bottlenecks. LB-TFC estimates, each time step, the number vehicles that should be held back or released by measures (i.e. VSLs RM rates) avoid capacity drop (maximizing outflow bottleneck). Afterwards, based on resulting estimated vehicles, and/or rates are increased decreased pre-specified order. In breakdowns, proposed controller anticipates future evolution bottleneck density using feed-forward structure. As result, performance is very efficient similar one obtained with an optimal while implementation (with almost instantaneous computation time) tuning parameters easy. second part this work, published separate (`Part 2: Simulation Comparison'), simulated, analyzed compared two freeways (one synthetic network stretch ring-road freeway SE-30 Seville, Spain).