Due to their high specific strength and stiffness, fiber reinforced structures are commonly used in high-performance applications. Their ability to be manufac-tured in thicknesses around 100μm makes them especially interesting in the field of deployable structures.
Modern deployable structures are mainly used for the folding and deployment of satellites to reduce the stowage volume in a launcher vehicle. However these structures also get a rising interest in medical application for example in the field of heart stents.
A novel design concept for an Heart Valve Replace-ment Stent has been developed at the Laboratory of Composites Materials and Adaptive Structures, which is promising to fulfill the challenging requirements of a biomedical implant.
Non-Invasively deliverable Transcatheter Heart Valve Stents require diameter changes of 250% to be delivered through the human circulatory system to their intended spot in the aortic annulus crown. After delivery, those structures have to deploy reliably and create a radial outward force onto the artery walls to be fixed at their intended position. Next to their crucial mechan-ical properties those structures shall also incorporate artificial polymeric heart valve leaflets replacing the diseased ones. Existing packaging concepts for those stents have already been developed at CMASLab and show promising results. Nevertheless, to further ex-pand the application range of the novel structures, new packaging concepts have to be developed taking into account the boundary conditions of different deploy-ment sites.
Due to their high specific strength and stiffness, fiber reinforced structures are commonly used in high-performance applications. Their ability to be manufac-tured in thicknesses around 100μm makes them especially interesting in the field of deployable structures. Modern deployable structures are mainly used for the folding and deployment of satellites to reduce the stowage volume in a launcher vehicle. However these structures also get a rising interest in medical application for example in the field of heart stents. A novel design concept for an Heart Valve Replace-ment Stent has been developed at the Laboratory of Composites Materials and Adaptive Structures, which is promising to fulfill the challenging requirements of a biomedical implant.
Non-Invasively deliverable Transcatheter Heart Valve Stents require diameter changes of 250% to be delivered through the human circulatory system to their intended spot in the aortic annulus crown. After delivery, those structures have to deploy reliably and create a radial outward force onto the artery walls to be fixed at their intended position. Next to their crucial mechan-ical properties those structures shall also incorporate artificial polymeric heart valve leaflets replacing the diseased ones. Existing packaging concepts for those stents have already been developed at CMASLab and show promising results. Nevertheless, to further ex-pand the application range of the novel structures, new packaging concepts have to be developed taking into account the boundary conditions of different deploy-ment sites.
This thesis should investigate efficient ways to pack-age a continuous shell fiber-reinforced polymeric structure and enable its deployment in confined environments like arteries or veins. This includes:
• Literature research on Transcatheter Heart Valves Stents and their requirements, foldable composite structures and their mechanics and material behavior.
• Familiarizing with existing concepts, the material and the advantages/limitations
• Design of novel packaging schemes to further improve packaging efficiency and reliable deployment, prediction of packaging efficiencies
• Structural design of the foldable structure increasing the structural stiffness while maintaining the packaging efficiency
• Manufacturing and deployment testing of a prototype of the structure and verifying the predicted packaging efficiencies and deployment forces
This thesis should investigate efficient ways to pack-age a continuous shell fiber-reinforced polymeric structure and enable its deployment in confined environments like arteries or veins. This includes:
• Literature research on Transcatheter Heart Valves Stents and their requirements, foldable composite structures and their mechanics and material behavior.
• Familiarizing with existing concepts, the material and the advantages/limitations
• Design of novel packaging schemes to further improve packaging efficiency and reliable deployment, prediction of packaging efficiencies
• Structural design of the foldable structure increasing the structural stiffness while maintaining the packaging efficiency
• Manufacturing and deployment testing of a prototype of the structure and verifying the predicted packaging efficiencies and deployment forces
Arthur Schlothauer
CMASLab ETHZ
Leonhardstrasse 21, 8092 Zuerich
arthursc@ethz.ch
Arthur Schlothauer CMASLab ETHZ Leonhardstrasse 21, 8092 Zuerich arthursc@ethz.ch