For this lab, you will design and build a heart rate monitor using an electrocardiogram (ECG) measurement system. This system will be sampled by the microcontroller ADC and processed by your code written in C++ to output the instantaneous heart rate to the serial terminal.
This will be a group lab. Each group will receive a bag with:
Wire, resistors, and capacitors needed for the lab are available in Singer 240.
Please sign up for a lab group here. Due to the space concerns, I can only support 8 lab groups of 3 (one group will be 2 because there are 23 students in the course). There is space to list your availability if you need help finding a group.
| Parameter | Value |
|---|---|
| ECG Lead | Lead I |
| ECG Output | ≥ 1 Vpp |
| ECG Gain | ~ 1000 |
| Vref | 2.5 V |
| Bandwidth | 0.1 to 50 Hz |
| Parameter | Value |
|---|---|
| Sampling rate | 100 Hz |
| ADC Resolution | 12 bits |
| ECG Resolution | ≥ 5 bits |
You will need to solder short wires to the ends of the ECG leads in order to use them with the breadboard. To do this, snip off the connector at the base of the leads and strip a short amount of the wire away using the wire strippers (see photo). Then, solder a short solid gage wire to the end of the wire. If no one in your group has soldered before, let Prof. Delano know and they will show you how to do it.
We will need to use MATLAB for this lab. If you’d like to use your own computer, be sure to set it up before the lab.
Design an ECG measurement circuit using the INA114 instrumentation amplifier and the 5V power supply that measures ECG in the Lead I configuration (see diagram). The output of the circuit should be at least 1 Vpp (if you assume an input signal of 1 mV, this requires a gain of 1000). The signal Vref can be generated using a voltage divider and op-amp buffer.
