This is one of the projects I work on at the Veterans Administration, East Orange. The goal is to acquire pulse oximeter data for studying and understanding stress and its effects on behavior.
For Measuring pulse ox data we use the Nonin OEM module and Nonin Forehead sensors.
For transmission we used the Xbee units(Zigbee IEEE 802.15.4)
The units were programmed to send the data to a base station where a Labview program was developed to view and store the data in real-time from these units.
The Zigbee units looks something like this-
Currently the system is undergoing an upgrade- we are moving from Zigbee to WiFi to increase data transmission capabilities, range and dependency on the system.
The Zigbee system though very effective was not giving the results we expected, the number of channels(14) limited the total number of participants for the study as well as caused loss
of reliability of the system.
The WiFi units that are currently being made have data loggers to aid them in logging accelometer data along with the ability to record and transmit plethysmograph data over longer
distances and more effectively.
The xbee module
The completed Zigbee Unit