The Application Of Fuzzy Neural Network Technology In Elevator Group Dispatch

With more intelligent buildings ware constructed and better service was need, the improvement of Elevator Group Dispatch has become an emergent problem. Many methods such as Fuzzy Control Approach and Neural Network Approach are already used in elevator group dispatch. Because of non-linear, random and ambiguous features of the elevator group dispatch, there are various drawbacks in these methods. Combining Fuzzy Inference with Neural Neuvork. the fuzzy neural network technology has great superiority in processing non-linear, random and ambiguous problems. So the application of fuzzy neural network in elevator group dispatch becomes one of focus in the field in home. But there is few theses to introduce fuzzy neural network technology about selecting elevator problem in the elevator group dispatch. So the thesis makes a primitive stud}' in this field.To realize dispatch, the Serial Communication between Epigny Computer and PLC must be first achieved. Due to the poor calculation capability and mutuality of the PLC which controls elevators, the Epigny Computer must realize the complicated dispatch calculation and the simulation of the elevator moving, collect the running data of the elevators and allocate responding-elevator. Therefore, the feature of the serial communication in the elevator group dispatch are analyzed in the thesis, such as communication parameter setting, one-side communication programming and real-time ability and reliability of communication. According to the MEWTOCOL-COM communication protocol of FP1-PLC, we construct parallel multi-communication module network structure and use VC to realize multi-threading high effective communication.The Hall Call Assignment Strategy that is usually used in the elevator group dispatch is chosen and analyzed. It is an Evaluation Function that takes Average Waiting Time (AWT), Long Waiting Probabilities (LWP), Power Consumptions (RNC) as Evaluation Standards:The three values are the key to the function and the core problem of fuzzy neural network approach's targets.According to the Fuzzy Rules in the fuzzy control approach that calculate the three evaluation standard values, and the limited lasting-time of responding hall call in the elevator dispatch, we construct three four-leveled new fuzzy neural network calculating the evaluation criteria values. The network with character of simple structure, small calculation and rapid arithmetic speed, realizes the reflection from the rules ( AWT. LWP and RNC) to the neural network. Its fuzzy node adopts Gauss Model Subjection Function, whose center-value and width-value exerts great influence on the network's operation transmission and performance, and needs modification by studying. Then the BP Algorithm is inferred in detail and adding momentum item is used to avoid local least and speed up die convergence of Average Error Function. To guarantee the physical meaning of the area-value and improve the significance among rules, we choose part-layer algorithm to modify the area-value between the third level and the forth one. Thus the BP algorithm only study die center-value, width-value and w, values. The improved parameters are saved in thedata file for dispatch.By taking the schedule operation realized by the successful fuzzy neural network as its core, study the problem of elevator moving simulation. On the premise guaranteeing the matter of elevator moving, state in details the simplicity of the numbers of elevator moving signals and the pre-processing of the network's inputting-variable. Successfully simulate and achieve the elevator dispatch procession: A, when an new hall call signal is found, calculating the AWT, , LWP, and RNC, through the network; B, getting the S, values of each elevator; then selecting the elevator with the biggest S, value to respond the new hall call signal; C, refreshing elevator cartoons and sending message to the PLC which controls the selected elevator.With FP1-C40 PLC in lab, develop software to simulate elevator group dispatch by using VC. In a word, the thesi...