My version of a DIY bend / flex sensor

I had to help one of my students in a project involving flex sensors. After trying several tutorials I decided to make a custom version with which I'm quite satisfied.

Here you can whatch the build-up video:

If you take advantage of the internal pullup resistor of Arduino's pin you can skip the external voltage divider resistor. Otherwise I suggest you use a 30k Ohm one.

And this is the code:

int sensorPin   = A0;    

int numReadings = 64;

int msDelayFor  = 1;

int msDelayLoop = 100;

int minMedian = 1023; 

/******************************************

 *                  SETUP

 ******************************************/

void setup() {

  Serial.begin(115200);

  pinMode(sensorPin, INPUT_PULLUP);

}

/******************************************

 *                  LOOP

 ******************************************/

void loop() {

  float median = 0;

  for (int i=0; i < numReadings; i++) {

    median += analogRead(sensorPin);

    // for stabilization between analog readings

    delay(msDelayFor); 

  }

  median /= float(numReadings);

  if ( median < minMedian) minMedian = median;

  Serial.println(median-minMedian);

 

  int currentDelay = msDelayLoop - (msDelayFor * numReadings);

  if (currentDelay > 0) delay( currentDelay );

}