UltrasonOS

February - December 2017
with Yazmin Feliz et al (Columbia University Creative Machines Lab)

We are developing a low cost, open source device called UltrasonOS with the aim of drastically reducing the barrier of access to life-saving ultrasound imaging technology. I created the initial PCB designs and subsequently managed a subteam to iterate upon the PCB designs while I also took on a large part of the microcontroller programming.

Designs and code on Github:

Analog Frontend - A transceiver circuit for 5 MHz ultrasonic imaging using a piezoelectric transducer. It utilizes the AD8331 Variable Gain Amplifier from Analog Devices and LTC5507 RF Power Detector from Linear Technology.
Nucleo DAQ Shield - A mixed signal PCB that houses connectors and auxiliary circuitry (buffers, H-bridge, voltage regulators). It allows the STM32 microcontroller to interface with the Analog Frontend, motor, and other sensors.
Code for STM32 - Performs high speed data acquisition and UDP data streaming to a client computer. I somehow managed to preserve my sanity as I journeyed through the thousand-page depths of STM32 documentation.

We designed the PCBs in Kicad and utilized a combination of the mbed and HAL libraries for the STM32 code. We ordered PCBs and stencils from OSH Park and OSH Stencils, respectively.