Fiber Optic Detecting and Control System for Gate Opening Liao Chuke Chen H ongboL iao Chuke: Assoc.Prof.,Center of Fiber Sensor,WUT,Wuhan430 0 70 ,ChinBy using two advanced optic fiber sensing technique and programmable logically controlling technique ,a new system of optic fiber sensing opening has been manufactured which can be used in large gate opening (especially in multi- level gate opening) .Because the detecting and sensing were realized by light ,therefore ,the problems of detecting ,control and Synchroni- zing have been solved.This System has the advantages of wide measurementrange,high accuracy,good stability and strong ability to resist disturbance.Itcan especially be used in the gate opening and control in various kinds of complex and harsh environment.fiber optic sensing technology; programmable logically control technology; gate opening