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DAMAGE.

#if defined(ARDUINO) && ARDUINO >= 100

#include "Arduino.h"

#else

#include "WProgram.h"

#endif

#include "EMGFilters.h"

#define SensorInputPin A0 //sensor input pin number

Define the `threshold` variable as 0 to calibrate the baseline value of input sEMG signals first.

After wiring the sEMG sensors to the Arduino board, wear the sEMG sensors. Relax your muscles for a few seconds,

you will be able to see a series of squared sEMG signals values get printed on your serial terminal.

Choose the maximal one as the baseline by setting the `threshold` variable. Then rebuild this project.

The `envelope`, which is the squared sEMG signal data, will be printed to the serial line.

The developer can plot it using the Arduino SerialPlotter.

Note:

After calibration, Any squared value of sEMG sigal below the baseline will be treated as zero.

It is recommended that you do calibration every time you wear the sEMG sensor.

unsigned long threshold = 0; // threshold: Relaxed baseline values.(threshold=0:in the calibration process)

unsigned long EMG_num = 0; // EMG_num: The number of statistical signals

EMGFilters myFilter;

Set the input frequency.

The filters work only with fixed sample frequency of

`SAMPLE_FREQ_500HZ` or `SAMPLE_FREQ_1000HZ`.

Inputs at other sample rates will bypass

SAMPLE_FREQUENCY sampleRate = SAMPLE_FREQ_500HZ;

Set the frequency of power line hum to filter out.

For countries with 60Hz power line, change to "NOTCH_FREQ_60HZ"

NOTCH_FREQUENCY humFreq = NOTCH_FREQ_50HZ;

void setup()

{

myFilter.init(sampleRate, humFreq, true, true, true);

Serial.begin(115200);

}

void loop()

{

int data = analogRead(SensorInputPin);

int dataAfterFilter = myFilter.update(data); // filter processing

int envelope = sq(dataAfterFilter); //Get envelope by squaring the input

envelope = (envelope > threshold) ? envelope : 0; // The data set below the base value is set to 0, indicating that it is in a relaxed state

/* if threshold=0,explain the status it is in the calibration process,the code bollow not run.