Ultrasonic Levitation with Software-Defined FPGAs and Electronically Phased Arrays

We present a software-defined platform for ultrasonic levitation research based on the Xilinx Zynq SoC using an array of ultrasonic transducers. The platform provides controlled movement of the levitated objects as well as object detection based on the received echo. Hardware acceleration of the phased calculations is obtained thanks to the programmable logic that deploys a user-defined and adaptive number of compute engines described in c++. Additional features available in the Zynq device that are deployed in this platform include the large number of parallel I/Os connected to the FPGA Mezzanine connector (FMC), the integrated ADC capabilities that enable the capture of echo signals and ambient temperature measurements used to correct the ultrasound wave delays. Both planar and spherical cap phased arrays are created and in this paper we investigate the capabilities and limitations of the different designs to improve the stability of the levitation process.