Application of Artificial Immune Controller to Freeway Ramp Metering

A biological immune system can respond to various antigens immediately and maintain adequate stabilization, which dues to the active and inhibitive function of T cells in different stages of the immune process. Based on the mechanism of B-cell cooperating with T-cell exhibited in biological special immune, an artificial immune control method is proposed, and is applied to freeway on-ramp metering. First, the freeway traffic flow model is built. Then the mechanism of a biological immune system is formulated. In conjunction with the feedback control theory, a freeway on-ramp metering is realized by using artificial immune controller. Finally, the control system is simulated in MATLAB software. Fuzzy logic on-ramp controller is also chosen in contrast to the artificial immune controller. The result shows that the artificial immune controller improves evidently on the aspects of response speed and dynamic performance. This method provides a novel and practical way to realize freeway on-ramp metering.