Deployment Force Fixture

Deployment Force Fixture Used During Testing

Implant

Inter-atrial Shunt Device

Background

This test fixture is used to measure the forces to deploy and retrieve an implant from the Inter-atrial Shunt Device (IASD) system. The fixture is mounted to a tensile tester and water pump system in order to simulate real use. A Thumb Slide Fixture (designed in conjunction with the deployment force fixture), as shown below, is attached to the handle of the device in order to advance and retract the implant from its sheath. The fixture accurately represents the femoral artery path to the heart in which the IASD will be fed through.

Thumb Slide Fixture

Problem

The previous design of the fixture did not properly secure the IASD allowing it to move slightly in every direction. This created unnecessary bending moments, compressive, tensile, and torsional forces that the device should not see during testing. Thus, yielding deployment and retrieval forces that did not meet Real Time and Accelerate Age testing standards.

Solution

3D printed and machined an array of parts listed and shown below in order to eliminate any movement / unnecessary forces the IASD would encounter.

Handle Cavity (3D Printed): Designed a mold of the handle to eliminate torsional movement of the IASD.
Latching Mechanism (3D Printed): Designed a peg feature underneath the part that presses up against release mechanism on IASD to allow the sheath and implant to advance while completely stabilizing the device during testing.

Release Mechanism

Handle Cavity

Tube Lifting Block

Support Blocks

Neck

Latching Mechanism

Support Blocks (Machined): Designed to secure the neck of the fixture to a 60 degree angle (+/- 0.5 degrees), which was considered worst case scenario for testing.
Tube Lifting Block (3D Printed): Designed to ensure the accuracy of the path from the femoral artery to the heart and properly guides the sheath of the IASD into the tubing.
Neck (Machined): Design and manually machined a U-channel neck to create a rigid connection between the handle cavity, latching mechanism, tube lifting block and the support blocks to ensure no bending moment occurs.