myDAQ Biomedical
Instrumentation Board
Group May1212
Jeremy Bruecken, Kossi Sessou, Alex Weiss
Mani Mina - Advisor
Andrew Watchorn - Client
National Instruments myDAQ
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Project
Plan
Low cost portable data acquisition unit
Interfaces with NI LabView software
Allows students to generate, measure, and analyze
signals in real time
myDAQ Details
Project
Plan
Problem Statement
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Project
Plan
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
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BioPac currently sole competitor in market
Iowa State recently purchased BioPac kits for
introductory class
Our product would be a simple unique solution
Project
Plan
Design
Functional Requirements
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Gain and filter signal from contact patches for EKG
and EMG to the myDAQ analog input
Provide user interface for sending, receiving, and
analyzing signals in LabView via myDAQ
Protect end user per IEC regulations
Design
Non-Functional Requirements
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Simple plug and play hardware interface
Provide user friendly software interface in LabView
40x lower price than BioPac
Allow for cheap and reliable manufacture
Design
Concept Sketch
Design
Filtering Methods
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Initial design included numerous hardware
components
Removed amplifier and passive elements and
replaced with software filtering
Lowers cost of product
Design
EKG & EMG Safety
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IEC compliant
Simple and effective
System is protected
from large voltage
spikes
Design
EKG & EMG Measurement
Burr-Brown INA121Application Note
Hardware
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Built circuit with passive components to verify
System Design
Used external Oscilloscope to verify output
Hardware
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Acquired Signal
Peaks are present in the acquired signal
Very little filtering is included in this signal
LabView Interface
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Capturing the Signals
Writes to file for processing
Implementation
Implementation
Signal Processing and Filtering
Front End – Acquire and Extract
Finished Board
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High Gain
amplifier
Easy
Connection
HPS shunt
diodes
No filtering
Task Breakdown
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Jeremy
 Complete
circuit design
 Perform Spice circuit analysis
 Hardware
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Kossi
 Create
LabView interface
 Performed interface and hardware testing
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Alex
 Performed
hardware testing
 Design webpage
Things learned
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Working with client
Obtaining proper documentation
Ethics and Proper procedures
Meeting deadlines
Handling design issues
Conclusion
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Digital filtering Vs. Analog
Noise issues
How can we build upon this project:
 Adding
more devices
 Adding functionality to program
 Increase accuracy
Questions?
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myDAQ
 NI
instrumentation learning tool
 EKG & EMG
 Filter and Gain
 Safety
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System Diagram