Counter loop on pressure sensors arduino - arduino

Question

I'm using four fsr pressure sensors in parallel connection to each other. Below are the coding for my project.
I have a problem with the counter values where it display four added counter values for each of the sensor.
I need to get a counter values where it is added each time pressure is detected and if there is no pressure anymore, it will remain the previous counter value.
int fsrPin[] = {0, 1, 2, 3};
int fsrReading;
int fsrVoltage;
unsigned long fsrResistance;
unsigned long fsrConductance;
long fsrForce;
int pinCount = 4;
int counter = 0;
void setup(void) {
for(int thisPin = 0; thisPin < pinCount; thisPin++) {
pinMode(fsrPin[thisPin], OUTPUT);
}
Serial.begin(9600);
}
void loop(void) {
for(int thisPin = 0; thisPin < pinCount; thisPin++) {
fsrReading = analogRead(fsrPin[thisPin]);
Serial.print("Analog reading ");
Serial.print(fsrPin[thisPin]);
Serial.print("=> ");
Serial.println(fsrReading);
fsrVoltage = map(fsrReading, 0, 1023, 0, 5000);
Serial.print("Voltage reading in mV = ");
Serial.println(fsrVoltage);
if (fsrVoltage == 0) {
Serial.println("No pressure");
} else {
// The voltage = Vcc * R / (R + FSR) where R = 10K and Vcc = 5V
// so FSR = ((Vcc - V) * R) / V
fsrResistance = 5000 - fsrVoltage;
fsrResistance *= 10000;
fsrResistance /= fsrVoltage;
Serial.print("FSR resistance in ohms = ");
Serial.println(fsrResistance);
fsrConductance = 1000000;
fsrConductance /= fsrResistance;
Serial.print("Conductance in microMhos: ");
Serial.println(fsrConductance);
if (fsrConductance <= 1000) {
fsrForce = fsrConductance / 80;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
} else {
fsrForce = fsrConductance - 1000;
fsrForce /= 30;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
}
}
for(int thisPin=0; thisPin < pinCount; thisPin++){
if (fsrForce != 0) {
counter++;
Serial.print("Counter = ");
Serial.println(counter);
} else {
counter;
Serial.print("Counter = ");
Serial.println(counter);
}
}
Serial.println("--------------------");
}
delay(3000);
}
The actual problem is as below where I need to find a correct condition for looping the value of the counter:
for(int thisPin=0; thisPin < pinCount; thisPin++){
if (fsrForce != 0) {
counter++;
Serial.print("Counter = ");
Serial.println(counter);
} else {
counter;
Serial.print("Counter = ");
Serial.println(counter);
}
}
FOUR COUNTER VALUES IN EACH ANALOG READING

Answer 1

I believe the main problem is that you are checking if fsrForce != 0, However fsrForce does not really have a chance to get to zero because it's dependent on fsrVoltage and is set only if fsrVoltage is positive.
Just set fsrForce = 0 when fsrVoltage < VOLTAGE_THRESHOLD and you should get the expected behavior.
Try this:
int fsrPin[] = {
0,
1,
2,
3
};
int fsrReading;
int fsrVoltage;
unsigned long fsrResistance;
unsigned long fsrConductance;
long fsrForce;
int pinCount = 4;
int counter = 0;
// add threshold
const float VOLTAGE_THRESHOLD = 0.2;
void setup(void) {
for (int thisPin = 0; thisPin < pinCount; thisPin++) {
pinMode(fsrPin[thisPin], OUTPUT);
}
Serial.begin(9600);
}
void loop(void) {
for (int thisPin = 0; thisPin < pinCount; thisPin++) {
fsrReading = analogRead(fsrPin[thisPin]);
Serial.print("Analog reading ");
Serial.print(fsrPin[thisPin]);
Serial.print("=> ");
Serial.println(fsrReading);
fsrVoltage = map(fsrReading, 0, 1023, 0, 5000);
Serial.print("Voltage reading in mV = ");
Serial.println(fsrVoltage);
if (fsrVoltage < VOLTAGE_THRESHOLD) {
// reset the fsrForce when there is no pressure
fsrForce = 0
Serial.println("No pressure");
} else {
// The voltage = Vcc * R / (R + FSR) where R = 10K and Vcc = 5V
// so FSR = ((Vcc - V) * R) / V
fsrResistance = 5000 - fsrVoltage;
fsrResistance *= 10000;
fsrResistance /= fsrVoltage;
Serial.print("FSR resistance in ohms = ");
Serial.println(fsrResistance);
fsrConductance = 1000000;
fsrConductance /= fsrResistance;
Serial.print("Conductance in microMhos: ");
Serial.println(fsrConductance);
if (fsrConductance <= 1000) {
fsrForce = fsrConductance / 80;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
} else {
fsrForce = fsrConductance - 1000;
fsrForce /= 30;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
}
}
for (int thisPin = 0; thisPin < pinCount; thisPin++) {
if (fsrForce != 0) {
counter++;
}
Serial.print("Counter = ");
Serial.println(counter);
}
Serial.println("--------------------");
}
delay(3000);
}