Technology for zero defect manufacturing of large composite parts

The processing chain involves four steps:

1. An inline quality control system scans the laid material during the lay-up process, providing immediate feedback about any quality problems that might exist. Once the layer is finished, the machine operator can immediately initiate any rework if required or continue with the next layer. Manual inspection after each layer is not needed.
2. Process monitoring during the infusion and curing process generates information that cannot yet be controlled directly. Through the integration of a sensor, the flow-front during infusion, temperature and state of cure can be measured along the whole sensor (not just in single positions). This allows a detailed analysis of the process, so that it can be stopped at the right time.
3. Defect data are collected in a “manufacturing database” that is then used with finite-element methods to calculate the impact of defects on the part’s mechanical strength. This allows an assessment of the part as it is manufactured and provides important input for rework processes.
4. A decision support tool merges all the above-mentioned data sources and combines them with a logistical part flow simulation. This information is presented to the operator to help decide about different rework strategies. Through these process monitoring steps, a wide range of typical defects can be detected and reworked if needed, so that substantially fewer (if any) defects show up during end-of-line inspection.

Key Benefits:
> No (or substantially reduced number of) defects showing up during final NDT
> Substantial productivity gains during lay-up due to automated inspection
> Optimized infusion and curing processes through direct sensor feedback
> Qualified decisions about re-work based on analysis of the part as manufactured
> Global view of the whole process using part flow simulation