Yang Zhang, Robert Xiao, and Chris Harrison have used a Teensy 3.2 to explore Electrical Impedance Tomography (EIT) sensing schemes.

Expanding on research from a gesture-sensing smartwatch, the system can select between traditional two-pole sensing, where a single pair of electrodes act as emitter and receiver, or four-pole, where an AC signal is used to measure voltage between two pairs. Eight, 16, and 32-electrode configurations of each allow extensive experimentation to explore advantages and drawbacks to each.

A custom PCB houses the Teensy 3.2, along with a voltage-controlled current source (VCCS), direct digital synthesizer (DDS) and ADC preamp, plus multiplexers to allow dynamic electrode schema selection. Find out more on Chris’s web site, check out the PCB on GitHub, read the research paper, or watch the video below.