Periodic Reporting for period 1 - BioStruct (Manufacturing process for bio-based fibre-reinforced composite parts for structural applications)
Reporting period: 2024-01-01 to 2025-06-30
The BIOSTRUCT project aims at the development of advanced technologies for the manufacturing of composite parts made from bio-materials. This will enhance the use of such materials in parts with structural requirements and thus reduce the need for conventional carbon and glass fibre composites.
Key technical topics:
• Natural products such as bio-based fibres have a higher variability in term of dimensions, weight and appearance. Nevertheless, high precision is required when handling fabric made of natural fibres, e.g. during the lay-up and draping of a composite part.
• The mechanical properties of natural fibres and resins need to be better understood to enable the accurate design of structural parts and thus make such material usable also for structural applications.
• The integration of bio-based load sensors will provide additional information and safety so as to reduce the uncertainties that are associated with bio-based composites.
Objective - O1
To develop automated high-precision handling systems that enable the accurate placement of fabric made from natural fibres in a mold. This includes the pick and place operation as well as control methods to ensure a match between the part “as designed” and “as manufactured” and the integration of cure monitoring systems.
Objective – O2
To develop material models that are able to capture the mechanical properties of natural fibre, bio-based resins, bio-adhesives and their combination in a composite.
Objective – O3
To implement a manufacturing process for an integrated load sensor based on micro-structured bio-materials.
Key technical topics:
• Natural products such as bio-based fibres have a higher variability in term of dimensions, weight and appearance. Nevertheless, high precision is required when handling fabric made of natural fibres, e.g. during the lay-up and draping of a composite part.
• The mechanical properties of natural fibres and resins need to be better understood to enable the accurate design of structural parts and thus make such material usable also for structural applications.
• The integration of bio-based load sensors will provide additional information and safety so as to reduce the uncertainties that are associated with bio-based composites.
Objective - O1
To develop automated high-precision handling systems that enable the accurate placement of fabric made from natural fibres in a mold. This includes the pick and place operation as well as control methods to ensure a match between the part “as designed” and “as manufactured” and the integration of cure monitoring systems.
Objective – O2
To develop material models that are able to capture the mechanical properties of natural fibre, bio-based resins, bio-adhesives and their combination in a composite.
Objective – O3
To implement a manufacturing process for an integrated load sensor based on micro-structured bio-materials.
Expected Outcome - EO1
A robotic workcell will be built with a specific gripper that is able to handle fabric made from natural fibre. The gripper will include vision-based sensors to control the positioning of the single plies and the orientation of the fibres when they are placed in the mold.
Despite the higher variability of natural fibres, the accuracy of the handling system will be in the range that is typically used for conventional fibres (<1mm). In terms of positioning accuracy a tolerance of less than 1mm will be reached and a range of +/-5° for fibre orientation.
Expected Outcome – EO2
Material models will be implemented in simulation software for finite element calculations, these will be able to predict the margin of safety for the particular load cases and thus enable the optimization of the parts in terms of weight vs. strength.
The accuracy of the models will be determined through standardized mechanical tests, using coupons (typical size ~20-30cm length) manufactured according to the standard. The accuracy of the predicted properties for bio-materials will be ±5% of the measured value, which will correspond to the accuracy of models of conventional (synthetic) fibre reinforced materials.
Expected Outcome – EO3
The manufacturing process will be realized on industrial equipment and will show the direct integration of a load sensor into the part. It will be applicable during the layup-process and minimize the use of “non-bio” components so as to avoid any negative impact on recyclability of the parts.
The measurement of the deformation using the integrated load sensor will achieve an accuracy of ±5% on coupon level parts and ±7% on real parts of the end users. The relative deviation will be determined through a 3D measurement system.
A robotic workcell will be built with a specific gripper that is able to handle fabric made from natural fibre. The gripper will include vision-based sensors to control the positioning of the single plies and the orientation of the fibres when they are placed in the mold.
Despite the higher variability of natural fibres, the accuracy of the handling system will be in the range that is typically used for conventional fibres (<1mm). In terms of positioning accuracy a tolerance of less than 1mm will be reached and a range of +/-5° for fibre orientation.
Expected Outcome – EO2
Material models will be implemented in simulation software for finite element calculations, these will be able to predict the margin of safety for the particular load cases and thus enable the optimization of the parts in terms of weight vs. strength.
The accuracy of the models will be determined through standardized mechanical tests, using coupons (typical size ~20-30cm length) manufactured according to the standard. The accuracy of the predicted properties for bio-materials will be ±5% of the measured value, which will correspond to the accuracy of models of conventional (synthetic) fibre reinforced materials.
Expected Outcome – EO3
The manufacturing process will be realized on industrial equipment and will show the direct integration of a load sensor into the part. It will be applicable during the layup-process and minimize the use of “non-bio” components so as to avoid any negative impact on recyclability of the parts.
The measurement of the deformation using the integrated load sensor will achieve an accuracy of ±5% on coupon level parts and ±7% on real parts of the end users. The relative deviation will be determined through a 3D measurement system.
Use case 1 addresses the manufacturing of the hull, spars and other structural components of a boat.
The electrically powered boat has a hull length of about 6m. It will be manufactured from natural fibres (flax) combined with bio-resins as approved for marine use. To further reduce the carbon footprint, reinforcements will be made from PET sheets and structural fillers from recycled bottles. The boat will suitable for up to wind force 6 and waves of up to 2m. Structural requirements will have to consider the hydrodynamic loads and impacts as the boat goes through the waves. Lightweight construction is of high relevance to reduce power consumption and will thus require and optimization of weight vs. mechanical strength.
Use case 2 is the manufacturing of rotor blades for wind energy power plants.
A wind blade of about 6m length will be designed and built for a small wind turbine. The maximum swept area allowed is 200m2 according to the classification of a small wind turbine in the IEC 61400-2 standard. Using this maximum swept area, the rotor diameter is about 16m corresponding to 20kW of rated power. So, the wind blade within the scope of the BIOSTRUCT project will be designed and manufactured for a 10kW wind turbine with an approximately diameter of 13m. The most suitable natural fibres will be identified together with a bio-based resin system and used for the manufacturing of the wind blade. The manufacturing process that will be adopted is the One Shot Blade® that allows to avoid the use of any structural adhesives increasing the recyclability features of the product compared to the conventional production system. Further, some of the work that is actually made by human will be automated to increase the accuracy and repeatability of the whole process by means of an automated draping device installed on an anthropomorphic robot.
The applications of BIOSTRUCT technologies are not limited to these use cases. Other examples include:
• Robotic draping is also applicable to conventional fibre-reinforced composite.
• Integrated load monitoring will be helpful for condition monitoring in other applications with higher structural requirements.
The electrically powered boat has a hull length of about 6m. It will be manufactured from natural fibres (flax) combined with bio-resins as approved for marine use. To further reduce the carbon footprint, reinforcements will be made from PET sheets and structural fillers from recycled bottles. The boat will suitable for up to wind force 6 and waves of up to 2m. Structural requirements will have to consider the hydrodynamic loads and impacts as the boat goes through the waves. Lightweight construction is of high relevance to reduce power consumption and will thus require and optimization of weight vs. mechanical strength.
Use case 2 is the manufacturing of rotor blades for wind energy power plants.
A wind blade of about 6m length will be designed and built for a small wind turbine. The maximum swept area allowed is 200m2 according to the classification of a small wind turbine in the IEC 61400-2 standard. Using this maximum swept area, the rotor diameter is about 16m corresponding to 20kW of rated power. So, the wind blade within the scope of the BIOSTRUCT project will be designed and manufactured for a 10kW wind turbine with an approximately diameter of 13m. The most suitable natural fibres will be identified together with a bio-based resin system and used for the manufacturing of the wind blade. The manufacturing process that will be adopted is the One Shot Blade® that allows to avoid the use of any structural adhesives increasing the recyclability features of the product compared to the conventional production system. Further, some of the work that is actually made by human will be automated to increase the accuracy and repeatability of the whole process by means of an automated draping device installed on an anthropomorphic robot.
The applications of BIOSTRUCT technologies are not limited to these use cases. Other examples include:
• Robotic draping is also applicable to conventional fibre-reinforced composite.
• Integrated load monitoring will be helpful for condition monitoring in other applications with higher structural requirements.