myDAQ Biomedical Instrumentation Board Group May1212 Jeremy Bruecken, Kossi Sessou, Alex Weiss Mani Mina - Advisor Andrew Watchorn - Client

National Instruments myDAQ Low cost portable data acquisition unit Interfaces with NI LabView software Allows students to generate, measure, and analyze signals in real time

myDAQ Details

Problem Statement National Instruments would like an add-on board to the myDAQ that will directly compete with the BioPac at a 40x price margin The board should provide the necessary connections and LabView interface to allow for measurements done in an introductory Biomedical Engineering course at Iowa State University

Market Survey BioPac currently sole competitor in market Iowa State recently purchased BioPac kits for introductory class Our product would be a simple unique solution

Functional Requirements Gain and filter signal from contact patches for EKG and EMG to the myDAQ analog input Power to two LEDs and collect light transmittance information for pulse oximeter Provide user interface for sending, receiving, and analyzing signals in LabView via myDAQ Protect end user per IEC regulations

Non-Functional Requirements Simple plug and play hardware interface Provide user friendly software interface in LabView 40x lower price than BioPac Allow for cheap and reliable manufacture

Concept Sketch

Burr-Brown INA121Application Note EKG & EMG Measurement Burr-Brown INA121Application Note

EKG & EMG Filter and Gain ANSI/AAMI EC-11 requires low-pass of 40Hz and high pass filter of .67 Hz Helps reduce 60Hz power noise Will limit capability of EMG measurement Gain of ~2000

EKG & EMG Safety Still researching IEC specification Options include optoelectric isolation, diode shunts, etc.

Pulse Oximeter Measurement Use variation in light transmittance to determine blood oxygen level and pulse Images Courtesy of freescale.com

Pulse Oximeter Measurement Pulse LEDs to get infrared and red absorption Gain photodector signal and filter for analysis www.ti.com/solution/pulseoximetry

Images Courtesy of freescale.com Pulse Oximeter Gain Use a transimpedance amplifier to generate a voltage signal Gain will require adjustment depending on finger thickness Images Courtesy of freescale.com

Images Courtesy of freescale.com Pulse Oximeter Filter 60Hz notch filter Low pass 6Hz filter High Pass .8Hz filter Images Courtesy of freescale.com

Pulse Oximeter Analysis Signal will have AC and DC components Use only AC to calculate oxygen level Provides pulse reading Images Courtesy of freescale.com

System Flow Diagram

LabView Interface Easy to use environment for capturing and analyzing biometrics

Labview Interface

Deliverables Prototype add-on board with sensors LabView software to collect and interpret data Design document Specification test document

Project Plan Create design document for December 4th Review design through Spice testing and analysis Parts ordered November 15th Begin hardware testing over break

Resource Requirements Access to BioPac for comparison testing IEC Safety Documentation Spice simulation tools Ability to order devices Circuit testing equipment (Oscilloscope, DMM, Power supply)

Risks Injury when performing tests of human body Proper safety circuitry will prevent injury Unable to meet 40x price margin goal Client is aware this is likely Inability to compete with BioPac Focus on price should attract wide customer base

Task Breakdown Jeremy Kossi Alex Complete circuit design Perform Spice circuit analysis Kossi Create LabView interface Perform interface and hardware testing Alex Perform hardware testing Design webpage

Questions? myDAQ EKG & EMG Pulse Oximeter System Diagram Project Plan NI instrumentation learning tool Add-on board to compete with BioPac EKG & EMG Filter and Gain Safety Pulse Oximeter 660nm and 940nm light absorption comparison System Diagram Project Plan Resource Requirements Risks Tasks