Design and experimental verification of an S-shaped continuous weft insertion system for soft–hard blended preform narrow channels

To address the limitations of the existing weft insertion technology in inserting carbon fiber bundles into the narrow channels of soft–hard blended preform, a proposed solution is to use a continuous weft insertion trajectory based on an S-shaped path for narrow channels. A weft insertion system that meets the process requirements has been designed. The analysis of the functional requirements for the continuous weft insertion system has identified five key nodes for the system, and the motion paths of each mechanism have been established. Through design methods such as analytical methods, rigid inversion methods, and mechanical analysis, the modular design of the system and the planning of the timing sequence for multiple mechanisms have been completed. Weft insertion experiments have been conducted on a continuous weft insertion system experimental platform, and the results demonstrate that the weft insertion system can effectively introduce carbon fiber bundles into the narrow channels, forming the expected S-shaped continuous weft insertion trajectory. This study verifies the feasibility of the designed weft insertion system and the accuracy of the continuous weft insertion theory, providing a viable solution for continuous weft insertion in the narrow channels of soft–hard blended preforms.