Presented at Actuator 2008, Bremen, Germany, June 2008
by D. Kaltenbacher and A. Schäfer, Fraunhofer Institut für Produktionstechnik und Automatisierung (IPA) and J. Rodriguez Jorge, Universitätsklinikum Tübingen
Researchers in Germany are investigating improved implantable hearing aids using a SQUIGGLE motor. Implantable hearing aids transmit sound waves mechanically to the ossicular chain using an electromechancial transducer, resulting in superior amplification and sound quality compared to classical hearing aids.
A key performance parameter is the applied initial load of the transducer towards the ossicular chain. Currently this load is adjusted by the surgeon during implantation using a micrometer screw, with limited accuracy due to the screw’s relatively large linear motion. Furthermore, no readjustment after the surgery is possible. Therefore hearing aid performance decreases as the bone tissue grows, causing the initial load between transducer and ossicular chain to change.
The researchers describe an active positioning system that would allow the adjustment of the transducer in situ at any given time, preserving optimal performance. The system technical requirements were investigated and summarized in this paper.
Visit the Actuator conference website to purchase the paper (2008 proceedings).