Sensor-driven process control for Resin Transfer Moulding of large aerostructures

Fibre-reinforced polymer composites (FRPCs), particularly those utilizing carbon fibre and epoxy resin, are increasingly crucial for modern commercial airliners due to their desirable specific stiffness and strength-to-weight ratio. Examples include the Airbus A350, where these materials play a vital role in lightweight structural applications. Typically, composite aerostructures are manufactured using prepreg materials arranged and cured within an autoclave under controlled pressure and temperature. This method offers high-quality components but can be very expensive and time consuming.

Liquid Composite Moulding (LCM) presents a promising alternative to prepreg/autoclave processing, where RTM is a specific version of LCM. LCM utilizes dry fibrous reinforcement placed in a mould that applies compaction pressure upon closure. The reinforcement is then impregnated with resin under a controlled flow-driving pressure gradient.

Once fully covered and impregnated, the composite cures within the mould. When implemented effectively, LCM, and by extension RTM, offers comparable product quality to autoclave methods while boasting shorter cycle times and lower component costs. The PhD project will consist of the following objectives to achieve the project aim:

Objective 1: Characterize Process Variability: This involves studying the extent and nature of variations in reinforcement properties and their impact on resin flow.

Objective 2: Develop Data Acquisition Systems for Process Monitoring: This includes designing, implementing and improving sensor systems to capture real-time data on resin flow rate, pressure, temperature, and potentially fibre arrangement during the RTM process.

Objective 3: Design Hardware Layout for Process Control: This objective focuses on configuring the control system hardware, such as actuators and valves and their integration with a variation of different moulds, to manipulate resin flow based on real-time data.

Objective 4: Develop Control System: This involves creating algorithms and system processes that can interpret sensor data and translate them into control actions for the hardware to optimize resin flow throughout the reinforcement.

Objective 5: Implement a Working Control System in an Industrial Demonstrator: The final objective involves integrating the developed control system with an existing industrial RTM setup to demonstrate its robustness, functionality and effectiveness in a large-scale setting for aerostructures that will be used by Airbus.