Proximal Aorta Pressure and Flow Control for Silicone Models Sponsored by: Medtronic

Completed by: Ben Allen, Trevor Borelli, Dante Garaventa, Cameron Vreugdenhil, and Michael Weatherson

Advised by: Dr. Dennis O’Connor

Project Overview

The product being delivered to Medtronic: ❖ Recreates the measured thoracic aorta flow and

pressure waveforms shown above to create a realistic stent graft deployment testing environment.

❖ Is operated via an easy to use LabVIEW program, which allows for real time data collection.

❖ Assembles in less than 45 minutes to allow for rapid deployment in test environments.

❖ Fits through most entrance ways to allow demonstrations for potential customers.

Program

Background Medtronic is a biomedical company which is an innovator in endovascular repair using non-invasive surgeries. This diagram shows a stent graft being deployed into an aortic aneurism. Medtronic is sponsoring this project to develop a system capable of simulating physiologically accurate blood flow through a silicone model lololol lp

in order to test the deployment of new stent graft designs.

Mechanical/Mechatronic Engineering Capstone Design Project 2015/2016

A program created in National Instrument’s LabVIEW operates the Pressure and Flow Control Systems through the use of control algorithms. The algorithms optimize the actuation of the pump and valve during simulation. Sensor feedback is utilized to ensure water flowing through the silicone model has the correct pressure and flow. Shown below is the graphical user interface, which allows the operator to input custom waveforms. The program can switch between blood flow simulation and a jog mode that allows the user to manually control the pump and valve. The program also incorporates safety features to ensure the pressure in the model is within safe operating limits.

The Proximal Pressure and Flow Control system is mounted on a mobile three-level cart. The top level houses a thoracic aorta model. Sensors include a pressure transducer and a flowmeter for monitoring the system. The pressure regulation system mounts to the outlet of the model to provide responsive changes to pressure within the model. The middle shelf houses the flow system and protects the motor from potential leaks. On the lower shelf, the various controllers, wiring, and power supplies are housed and protected by clear plexiglass shieldings.

System

The components of the Pressure and Flow Control system are shown above. A linear actuator pinches a tube to restrict flow out of the aorta model. The restriction of flow increases pressure in the system. A cross section of the valve structure is shown to the righ lo

Flow & Pressure Regulation

right. A servo motor actuates a gear pump to deliver consistent dynamic flow through the aorta. Both the motor driver and linear actuator driver use encoder feedback to ensure accuracy of velocity and position of the two components. This precision is necessary to accurately simulate blood flow.