In this assignment you will build a device to measure electrocardiogram between two electrodes attached only to the hands. The circuit will then be combined with the Finger Plethysmograph from the last assignment to estimate blood pressure.
Use the circuit given in Design of a Gel-Less Two Electrode ECG Monitor, but don't build the optional reference drive attached to the gain-setting resistor or the power supply. For the instrumentation amplifier, use a INA116. Electrodes will need to be large surface area for reasonable noise. YOu may need to provide a ground plane under the circuit to lower 60 Hz pickup.
If you nneed more filtering, a matlab program can be used to test filter techniques. The program simulates a QRS wave, then low pass, high pass, and LMS notch filter. The LMS filter is narrow band and only works for one frequency near 60 Hz. Adding four taps allows surpression of third harmonic distortion also. A more general n-tap LMS filter is shown in this program will surpress broadband interference.
You will need to implement Pan-Tompkins QRS detection. This matlab program uses physiobank data as input, adds noise, then filters to produce example output. Note that you cannot use the filter function for realtime filtering. You must implement the filter yourself.
You estimate blood pressure by the pulse pressure wave velocity.
Novel dry electrodes for ECG monitoring, Anna Gruetzmann, Stefan Hansen and Jorg Muller ,
Physiol. Meas. 28 (2007) 1375–1390 (pdf)
Design of a Gel-less Two-Electrode ECG Monitor, Emile Richard, Adrian D. C. Chan,
Medical Measurements and Applications Proceedings , April 30 2010-May 1 2010 (CU library link)
A Real-Time QRS Detection Algorithm, JIAPU PAN AND WILLIS J. TOMPKINS, (CU library link)
The Principles of Software QRS Detection, Reviw and compare algorithms,
Bert-Uwe Köhler, Carsten Hennig, Reinhold Orglmeister (CU library link)
Chapter 4 -- Event Detection, Dr. Bülent Yilmaz
Analysis of First-Derivative Based QRS Detection Algorithms
A Real-Time Microprocessor QRS Detector System with a 1-ms Timing Accuracy for the Measurement of Ambulatory HRV
Relationship between arterial pressure and pulse wave velocity using photoplethysmography during the post-exercise recovery period
Blood pressure estimation from pulse wave velocity measured on the chest
CONTINUOUS BLOOD PRESSURE MONITORING USING PULSE WAVE DELAY
Optical pulse wave signal analysis for determination of early arterial ageing in diabetic patients
Case study of ECG signal used as a reference signal in optical pulse transit time measurement of blood flow –
The effect of different electrode placements on pulse transit time
Pulse transit time as an indicator of blood pressure.
Blood Pressure Estimation based on Pulse Transit Time and
Compensation of Vertical Position
Your written lab report should include the sections mentioned in the policy page, and :