| Carbon fiber fabric is a reinforced structural skeleton of composite materials,which can improve the characteristics,so that it can resist stress concentration,mitigate impact damage and prevent crack propagation.During the weaving process of carbon fiber angle looms,the yarn path is long,the number of weaving layers is large,and the system structure is complicated.The traditional control method is used for wiring,which is not conducive to remote monitoring and control.According to the development trend of automation,intelligence and networking,networked control method containing intelligent nodes can effectively reduce the complexity of system wiring,and facilitate fault diagnosis and maintenance.At the same time,network induced delay and packet loss in networked control will affect the yarn tension of the loom opening system.This paper focuses on how to maintain the stability of yarn tension in the opening system.First,this paper introduces the overall working principle and main technical indicators of the loom,and analyzes the movement timing diagrams of the five core mechanisms of the loom,and then analyzes the entire yarn movement process during the formation of the angle interlocking fabric.By considering the influencing factors of the yarn tension,the change of the yarn tension during the opening movement was studied,and the dynamic analysis of the let-off spindle was carried out.The opening system tension control system model was established by combining the opening mechanism and the let-off mechanism.Based on the yarn tension control model of the opening system,the principle of yarn tension feedback control is analyzed,and an adaptive fuzzy PID controller is designed.By setting up the tension system True Time simulation structure platform,the two methods of PID control and adaptive fuzzy PID control are simulated according to different delay and packet loss parameters,and the results are compared.The results show that under the same conditions,the adaptive fuzzy PID control method has lower overshoot,stronger system stability and better control effect.As delay and packet loss increasing,the tension fluctuation is gradually increased,and the system stability is gradually deteriorated when the adaptive fuzzy PID control method is used.Aiming at this problem,a networked control system model was established using switched system method based on considering delay and packet loss,and exponential stability analysis was performed using Lyapunov function.Then,a state feedback controller for the networked control system is designed to compensate for the effects of delay and packet loss on the tension control system.The results show that the designed controller has no overshoot and strong anti-interference performance.It can reach stability within 1.5s under different influencing factors,and has a good control effect on the presence of different delays and packet loss. |
