All posts by Mostafa A Atalla

TU DELFT – Ultrasonic Friction Modulation of Catheters

This Project is funded by TU Delft as part of the cohesion projects grants

In cardiovascular interventions, in order to safely reach the heart,  catheters  (and guidewires) need to easily follow the curves in the  vascular  system,  while  creating  as  little  friction  as  possible to avoid damaging the blood vessel wall.  While low friction is beneficial during navigation, it makes holding the catheter at a specific location in open spaces, such as inside the heart, difficult during the execution of the procedure (thus, limiting the force transmission capability and the stability). The aim of this project is to develop a novel class of catheters whose frictional properties are controllable and can be adjusted depending on the phase of the catheterization procedure using the ultrasonic friction modulation technique which has been widely adopted in surface haptics applications.

Shark-Skin Inspired Lattice Structure for Drag Reduction

Sharks are extremely diverse group of vertebrates and inhabit a wide variety of aquatic habitats. The skin of sharks is covered in thousands of tooth-like denticles or scales that are anchored to the collagenous layer of the skin known as the  stratum  laxum.  These  scales  play  an  important  role  in  locomotion in  terms  of drag  reduction  and  lift  production. Despite  numerous  studies  on  the  functional  significance  of  shark  denticles , no  studies  have  been performed  to  investigate  the  effect  of  the  anchoring  of the  denticles  in  the  skin or the effect of denticle shape change on the drag reducing and lifting abilities. Moreover, no studies to date have been conducted to study the effect of the denticles stacking and overlapping on the denticles performance.

The objective of this project is to take  the first steps in understanding the effect of shark denticle morphology(roughness, waviness, texture), stacking, and anchoring on the drag reducing and lift increasing properties of the shark skin using computational models and real-life biomimetic shark skin prototypes.

A compatible literature study is available for this project which is “Review of denticles in sea animals”. The objective of this study is to make an overview of the existing denticles in sea animals, the differences in their design and their influence on the drag reduction for these sea animals.

Interested? Contact Aimée Sakes: A.Sakes@tudelft.nl or Jovana Jovanova: J.Jovanova@tudelft.nl or Mostafa Atalla: M.A.A.Atalla@tudelft.nl

Variable Friction Catheter

In cardiovascular interventions, Catheters are typically inserted in the radial or femoral artery and are navigated through the arteries to the heart, where the interventions are performed.  In order to safely reach the heart,  catheters  (and guidewires) used during these procedures need to be able to easily follow the curves in the  vascular  system,  while  creating  as  little  friction  as  possible to avoid damaging the blood vessel inner wall.  While low friction is beneficial during navigation, it makes holding the catheter at a specific location in open spaces, such as inside the heart, difficult during the execution of the surgical procedure. Thus, it limits the force transmission capability of the catheter. In this project, we look forward to developing a new variable friction catheter which can be modulated to have low friction while navigating and high friction while performing the surgical task to ensure optimal performance and outcomes in both cases.

The assignment is currently available with compatible literature review assignments. Interested? Contact Mostafa Atalla: m.a.a.atalla@tudelft.nl