ECE 1270 Labs


Project : Biomedical Sensors

ECE 1270 Course Website
Analog Lab Equipment Documentation and Tutorials

Students will be introduced to a variety of physiological sensors as they build a patient monitoring system. At the conclusion of the course, the students will have built and tested at least three different circuits for measuring vital signs such as respiration rate, blood oxygenation [oximetry, Barker], and heart rate. The projects will be integrated by their common theme, and they will cross disciplinary boundaries with bioengineering. These projects will be expanded in Electronics II. These projects are related to the research of Dr. Christensen and others in Bioengineering [Christensen] and Dr. Cotter [Douglas].

Lab 0: Laboratory Instruments

Lab Handouts:

Lab Zero Handout (PDF)

Lab Hardware Resources:

  • Analog / Digital Oscilloscope
  • Adjustable Power Supply
  • Waveform Signal Generator

In this laboratory exercise, you will be guided through some simple experiments illustrating the use of laboratory instruments. You will learn how to measure and display voltage waveforms, (created by a waveform generator), on an oscilloscope. You will also hook up a circuit with a resistor and a Light Emitting Diode (LED).

Lab 1: Design of a Myogram Circuit

Lab Handouts:

Lab 1 Handout (PDF)
Lab 1 Report pts
Lab 1 Notebook pts

Lab Hardware Resources:

  • Oscilloscope
  • Power Supply
  • Multimeter

Lab Software Resources:

Bio-sensing platform — Lab 1 – Electromyogram: The goal is to choose a pre-amp circuit design that increases the drive capability of the electrode signal without drawing appreciable current. Second, choose resistor values for a differential amplifier so that it multiplies the difference in the electrode voltages. Third, use the completed circuit to measure the myogram signals with the help of an oscilloscope and LabView® and Matlab® to capture and analyze data. Fourth, write a formal report on the measurements of actual EMGs.

Lab 2: Visual Perception Experiments

Lab Handouts:

Lab 2 Handout (PDF)
Lab 2 Report pts
Lab 2 Notebook pts

Lab Hardware Resources:

  • Oscilloscope
  • Power Supply
  • Multimeter

Lab Software Resources:

Bio-Sensor System — Lab 2 – Flicker frequency for fovea vs peripheral vision: students build circuit that flashes an LED at low rate. They determine fusion frequency where LED appears to be on all the time as opposed to flickering. They also observe that LED appears to flash twice as fast when viewed in periphery vs straight on. Teaches simple RC circuits and op-amp used as comparator.

Lab 3: A Model of Tissue Impedance

Lab Handouts:

Lab 3 Handout (PDF)
Lab 3 permittivity and conductivity doc (20 MB, pdf)
Lab 3 permittivity and conductivity web links (see Tables 4.7, 4.8 and Figs. 4.12 and 4.13)
Lab 3 Report pts
Lab 3 Notebook pts

Lab Software Resources:

Bio-Sensor System — Lab 3 – Circuit model of tissue impedance: students measure voltage drop (with tissue as part of voltage divider which thus gives current too) across biceps vs frequency and then model the impedance of the tissue by fitting the data to an RC model. Teaches concept of impedance and calculations with impedance values.