Three Steps 261 Three Steps to Make the Traffic Circle Go Round

Withgrowing traffic, control devices at traffic circles are needed: signals, stop/yield signs, and orientation signs—a special sign that we designed. We create two models—one macroscopic, one microscopic—to simulate transport at traffic circles. The first models the problem as Markov chain, and the second simulates traffic by individual vehicles—a “cellularautomata-like” model. We introduce a multi-objective function to evaluate the control. We combine saturated capacity, average delay, equity degree, accident rate and device cost. We analyze how best to control the traffic circle, in terms of: