As part of the medical technology research portfolio of the Mechatronics Research Unit, low intensity pulsed ultrasound (LIPUS) has been investigated over almost a decade now. In collaboration with the university hospital Regensburg, the research was aimed at using ultrasound to accelerate the in-vitro growth rate of chondrocytes (cartilage) for tissue engineering purposes. The work of the MRU included the development of high frequency (1.5 MHz) sources and amplifiers in order to drive the ultrasound generating piezoelectric elements. This also included extensive evaluation of such elements which are far from identical. Using needle hydrophones and a 6-axis robot, a complete 3D scan of the ensuing beam profile can be obtained.
This information, together with thermographic images, can be used to evaluate and characterize individual piezoelectric elements.