Here is a quick update on last week's activity on our Biosensor Array project for the GGHC. During our meeting on Saturday (Bill, Drew and myself), we performed the first integrated tests of 2 sensors connected to the same board (EKG and CO2), and we noted good results.

Dan playing biosensor guinea pig

     Dan playing biosensor guinea pig at Pumping Station: One on Saturday



This is an update from our side:


  • We have a functional EKG sensor that I am moving to a proto board
  • Bill has a functional CO2 sensor mounted on a respirator mask with a fan for flow rate detection (as describe in his previous posts)
  • Shawn's temperature sensor works as intended
  • Drew creating new finger cuffs to decrease false positive events from the GSR (galvanic skin response) sensor
  • Oximetry sensor is still work progress


EKG and CO2 signals visualized in one of the OpenEEG programs, Electric Guru:


EKG and CO2 signals visualized



The heart of the EKG sensor is an instrumentation amp (INA114) which amplifies the small voltage difference between chest probes.  This type of amp is very good at eliminating the common mode signal the probes share which is predominantly 60Hz from AC power everywhere in the building:

EKG sensor on breadboard