Design and Realization of a Highly Compact Tubular Linear Actuator for a Novel Total Artificial Heart

The
ShuttlePump
is a novel implantable total artificial heart (TAH) concept based on a linear-rotary actuator and currently under development at the Power Electronic Systems Laboratory, ETH Zurich, in close partnership with Charité Berlin and the Medical University of Vienna. This article presents the analysis, design, and realization of the
ShuttlePump
linear actuator (LA) part, which is necessary to provide about 45 N of axial actuation force. Design criteria are minimization of volume and generated power losses in the winding, which could result in excess heating and/or blood damage, i.e., protein denaturation and aggregation. The LA is implemented as a tubular LA (TLA) to maximize the active area for linear/axial force generation. After a preliminary analysis based on first principles, the TLA is optimized in detail with the aid of FEM simulations. The experimental measurements conducted on the realized TLA prototype verify the FEM simulation results and confirm the suitability for the realization of the
ShuttlePump
TAH.