Project information

• Start: June 2020
• Status: Pivoted - See Study 4 to see new direction
• Lab Website: Experimental Biomechanics Laboratory
• Authors: E. G. Haas, E. D. Krech, E. A Friis
• Funding: K-INBRE P20 GM103418

The goal of this research is to understand composite piezoelectric stack generators to inform implant design decisions and understand effects on overall voltage output. The addition of compliant layers between piezoelectric discs in piezoelectric generators stacked mechanically in series and wired electrically in parallel significantly increased power output for a given PZT volume. This study was designed to elucidate the effects of individual discs within a CLACS stack over load and frequency ranges used in biomedical applications to optimize power generation and design. New techniques of measurement and analysis of the voltage generation of individual discs were developed. These new techniques better control many of the specimen features by improving the manufacturing process. Specimens were dynamically tested under load-control at frequencies of 1, 2, 3 and 5 Hz through a sweep of resistances. Voltage data was acquired and analyzed using MATLAB. Data gathered was analyzed to track individual disc outputs during testing to compare maximum output voltages for each disc within stacks. Percentages of total voltage output from the stack were calculated for each disc as well as variation of each disc from the mean output voltage for each resistance, load, and frequency.

This study was pivoted due to durability challenges imposed by the new wiring arrangement of these specimen. A redirection was made to do a more thorough theoretical analysis to reduce scale of manufacturing for future laboratory testing.