Design of an HP-RTM Flow Monitoring System Based on Embedded Capacitive Sensors

This study addresses the challenge of optimizing high-pressure resin transfer molding (HP-RTM) by proposing a low-cost, high-precision embedded capacitive sensor system for monitoring resin flow. The system uses an FDC2214 capacitive-to-digital converter for signal generation and a PLC for signal acquisition, with protocol conversion enabling communication. A custom PLC program and interface allow real-time capacitance data collection and display. Resin flow into the sensor area causes measurable capacitance changes, enabling visual monitoring. An experimental setup with a transparent mold validated the system, showing minimal error between observed and measured flow front positions. This work improves HP-RTM quality control, boosts product quality and efficiency, and enhances the competitiveness of HP-RTM technology.