Properties of a Fully Printed Ultrasound Transducer on Flexible Substrate

Human-machine interfaces are looking for ever tinier sensors with barely perceptible interfaces to collect and interpret data from the musculoskeletal system. Ultrasound, for example, appears as a key technology to observe muscle mechanics during movement due to its ability to penetrate human tissue. Recently, wearable research platforms have emerged that enable wireless ultrasound measurements. However, existing transducers are still rigid and bulky, do not fit well to human anatomy, and cannot be attached to the body. To overcome these limitations, we present a fully printed ultrasound transducer made of the piezoelectric copolymer P(VDF-TrFE). We demonstrate the use of screen and inkjet printing to produce our transducers and evaluate their characteristics in a laboratory environment. With our assembled transducer stack, we observe the resonance frequency at 17 MHz. In addition, a bending radius of 3.5 mm promises good adaptability to human anatomy.