Kelu Ghosh's Raspberry Pi Pico W-Powered "pic0rick" Delivers Low-Cost Ultrasound Experimentation
The successor to the FPGA-powered un0rick and lit3rick, the pic0rick aims to fill a test equipment gap.
Maker Kelu Ghosh is trying to bring ultrasound testing to as broad an audience as possible β and to that end has unveiled the pic0rick, an ultrasound pulse-echo system powered by a Raspberry Pi Pico W and its RP2040 microcontroller.
"Non-destructive testing and imaging ultrasound modalities have been around since the '50s. More and more ultrasound-based initiative are emerging, mostly focusing on image processing β while the hardware has been left behind," Ghosh explains.
"Several teams have produced successful designs for the different possible uses," Ghosh continues, "mostly efforts from research laboratories. Most have been used on commercial US scanners, traditionally used as experiment platforms, but they are not cheap, and yield very little in terms of data access and control. Others have been developed in labs, but, sadly, very few have been open-sourced."
Ghosh's earlier work to address this resulted in the un0rick, an ultrasound acquisition and processing board based on the Lattice Semiconductor iCE40 HX4K field-programmable gate array (FPGA), followed by the cost-reduced lit3rick which moved to an iCE40 UP5K. The pic0rick does away with the FPGAs altogether, in favor of the Raspberry Pi RP2040 microcontroller on a Raspberry Pi Pico W board.
"The FPGA board is now a couple of years old, components got obsolete, so [I'm] anticipating the next gen devices. This pulse-echo system is made of three boards," Ghosh explains. "A single-channel ultrasound receive board with a fast ADC (up to 100Msps [megasamples per second]); a Β±24[V] voltage supply board; [and] a high voltage bipolar pulser.
"This is not a medical ultrasound scanner! Itβs a development kit that can be used for pedagogical and academic purposes β possible immediate use as a non-destructive testing (NDT) tool, for example in metallurgical crack analysis."
Design files and source code for the pic0rick are available under the TAPR Open Hardware License on the project's GitHub repository; a kit of parts is available to order on Ghosh's Tindie store at $299.