Timed Petri net based approach for elevator group controls

An optimal group control for elevator systems is proposed with a timed Petri net based approach. The elevator system is modeled by timed Petri nets and hall call waiting times are estimated with a moment generating function method, which is applicable to real traffic patterns. Two assignment policies are proposed to satisfy the demands of passengers (i.e. hall/car calls) and to handle exceptional situations. The performances of the elevator system employing the proposed policies are compared with each others by several performance indices