Compliant mechanism with hydraulic activation used for implants and medical instruments

摘要

The hydraulic actuation of cochlear implant is considered in this research. The deformation behavior of the compliant mechanism by hydraulic actuation is of interest to facilitate the insertion of the implant or the instrument used in the non-linear access paths to the target area, and to avoid any damage, which could occur during the surgical procedure. The described implant is a hydraulically actuated compliant structure with a symmetric internal hollow core and with a non-stretchable thin fibre embedded in the wall. Under inner pressure of 6 bar, the structure is bended, thus the insertion will facilitate during the operation. With the help of the simulations, a specific geometry of the compliant structure is determined for the target deformation executed by hydraulic actuation. In this paper a Finite Element (FE) model and an analytical model is demonstrated for simulation the deformation behavior of the fibre The maximum difference between both model results for simulated fibre curves is about 0.5 mm. This is 1.6% of the entire length of the implant.