NUMERICAL DESIGN OF STEERABLE GUIDEWIRES

Biomedical devices are an integral part of the medical industry nowadays. With the increase in cases of heart disease, catheterization procedures are becoming more frequent. Small-scale actuators are needed for the guidance of small-scale catheters and guidewires to remote targets in the human body. Numerical modelling is needed to guide the experiments in developing such steerable devices and to optimize their design. Here, we designed small-scale steerable guidewires by first developing bending actuators and then assembling them with guidewires. The actuators use materials with strain response to electric potential in a very low voltage range that is not harmful to the human body. Our work examined the layered strip configuration for the structure of actuators and identified trends to maximize the bending deformations. Using the commercial software Abaqus, we developed a finite element model based on Piezoelectric actuation to simulate various combinations of materials and geometries and to optimize the design of the actuator and the steerable guidewires. We also developed an analytical model for the actuators and showed that the simulation results are in agreement with the analytical model. Parameters like thickness, length, and different geometrical combinations and their effect on bending were compared. This numerical model can be customized for different materials that can be used for designing these actuators in future.