In a groundbreaking move to democratize ultrasound testing, maker Kelu Ghosh has unveiled the pic0rick, a low-cost ultrasound pulse-echo system powered by the Raspberry Pi Pico W and its RP2040 microcontroller. This innovation aims to make non-destructive testing (NDT) and ultrasound experimentation accessible to a wider audience, fostering both educational and academic use.
"Non-destructive testing and imaging ultrasound modalities have been around since the '50s. More and more ultrasound-based initiatives are emerging, mostly focusing on image processing — while the hardware has been left behind," says Ghosh, highlighting a gap in the advancement of ultrasound technology.
The pic0rick builds on Ghosh’s earlier work, which includes the un0rick, an ultrasound acquisition and processing board using a Lattice Semiconductor iCE40 HX4K FPGA, and the cost-optimized lit3rick, which moved to an iCE40 UP5K FPGA. The pic0rick takes a different approach, eliminating the need for FPGA boards by leveraging the Raspberry Pi RP2040 microcontroller. This shift not only reduces costs but also simplifies the system, making it more accessible for users with varying levels of technical expertise.
"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," explains Ghosh. The system includes a single-channel ultrasound receive board with a fast ADC capable of up to 100Msps, a ±24V voltage supply board, and a high-voltage bipolar pulser.
The device, however, is not intended as a medical-grade ultrasound scanner. Ghosh emphasizes its purpose as a development kit designed for pedagogical and academic applications. "This is not a medical ultrasound scanner! It’s a development kit that can be used for pedagogical and academic purposes — possible immediate use as a non-destructive testing (NDT) tool, for example in metallurgical crack analysis," he says.
Ghosh also notes the challenges faced by researchers and developers working on ultrasound systems. "Several teams have produced successful designs for the different possible uses," he explains, "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."
By focusing on affordability and accessibility, pic0rick aims to bridge this gap. Its open-source design ensures that users not only gain access to the hardware but also have the ability to explore, modify, and improve it. This aligns with Ghosh’s vision of enabling innovation and collaboration in ultrasound experimentation.
The pic0rick is poised to find applications in various fields, including non-destructive testing for metallurgical crack analysis, while also serving as an educational tool for aspiring engineers and researchers. With its innovative design and focus on accessibility, it marks a significant step forward in bringing ultrasound technology to a broader audience.
