Title
A Variable Bending Stiffness Instrument: The AlKingScope: A Proof of Concept Prototype
Author
de Koning, Alec (TU Delft Mechanical, Maritime and Materials Engineering; TU Delft Medical Instruments & Bio-Inspired Technology)
Contributor
Trauzettel, F. (mentor) 
Wu, Di (mentor)
Breedveld, P. (graduation committee)
Loeve, A.J. (graduation committee)
Degree granting institution
Delft University of Technology
Programme
Mechanical Engineering
Date
2022-07-08
Abstract
When treating a Chronic Total Occlusion (CTO) via Percutaneous Coronary Intervention (PCI), a guidewire first needs to be passed through or around the occlusion, a task requiring considerable skill and clinician experience. Proper backup support for the guidewire being used by the clinician is a prerequisite to prevent buckling or uncontrolled movement. Three different concepts that can vary their stiffness were generated, prototyped and evaluated against each other. Finally, a mechanism was designed that can vary its stiffness drastically by radially jamming wires together between a braided sheath and a radially rigid core that is also flexible in bending. Friction between the wires and the steerable segment generates the stiff configuration. If the braided sheath is released the wires can move along each other and the mechanism is flexible. The variable stiffness ability was tested by clamping the mechanism into a frame while applying a load to the distal tip. This resulted in a force-displacement curve that was 20 times stiffer in the stiff state than in the flexible state. The use of a braided sheath in a Variable Stiffness Mechanism (VSM) is an effective and
simple way to obtain variable stiffness. The proposed design is a step forward in the developing process for VSM for cardiovascular applications.
Subject
Variable bending stiffness
Coronary interventions
Additive manufacturing
Mechanically steered
Axial stiffness
Central channel
To reference this document use:
http://resolver.tudelft.nl/uuid:86a38591-5631-4440-9cd9-d4e83027b397
Embargo date
2024-07-08
Part of collection
Student theses
Document type
master thesis
Rights
© 2022 Alec de Koning