Digital control system of tension during the formation of flexible-oriented three-dimensional composite preforms

Tension control is a main event during the formation of a flexible-oriented three-dimensional composite preform, which determines the forming quality of preform. However, control error and fluctuation of existing carbon fiber control system cannot meet the needs of weaving flexible-oriented three-dimensional preforms, which is prone to cause poor consistency of the edge of preform. In this research, a novel tension control mechanism is proposed, which including rewind roll, piezoelectric ceramic actuator, idle roller and tension sensor. The influence of structural and process parameters are investigated using the established tension control mechanism model. Considering the modified Euler formula and micro-deformation behavior of carbon fiber, a tension control model for the unsteady-state moving carbon fiber is then proposed. An adaptive fuzzy controller is designed for tuning the PID parameters to control the moving distance of piezoelectric ceramic actuator. Furthermore, the proposed mechanism and control method are applied to a digital tension control system. Simulations and experiments show that the system can achieve high-precision control of tension with a target of 500 mN, residual error and control error rate of tension control system are within 3 mN and 0.6%, respectively. Application of the established system to flexible-oriented woven process significantly improves the consistency of edge of preform.