Hey guys, So I am expanding on Electronoobs Inductance tester (How to make a inductance meter using arduino)
And I am trying to avg/smooth the values for “inductance” and my values that are spit out are about a little less than half the original value. Ive tried different methods of smoothing and avging the value.
Anyone know whats going on here? I assume the program is handling the value differently? Attached is the code.
#include <SoftwareSerial.h>
//LCD config
#include <Wire.h>
//13 is the input to the circuit (connects to 150ohm resistor), 11 is the comparator/op-amp output.
double pulse, frequency, capacitance, inductance;
const int numReadings = 10;
double readings[numReadings]; // the readings from the analog input
int readIndex = 0; // the index of the current reading
int total = 0; // the running total
double average = 0;
int inputPin = A0;
SoftwareSerial LCD(9,10);
void setup(){
LCD.begin(9600);
Serial.begin(115200);
pinMode(11, INPUT);
pinMode(13, OUTPUT);
Serial.println("Why hello!");
delay(200);
for (int thisReading = 0; thisReading < numReadings; thisReading ++){
readings[thisReading] = 0;
}
}
void loop(){
digitalWrite(13, HIGH);
delay(10);//give some time to charge inductor.
digitalWrite(13,LOW);
delayMicroseconds(100); //make sure resination is measured
pulse = pulseIn(11,HIGH,5000);//returns 0 if timeout
if(pulse > 0.1){ //if a timeout did not occur and it took a reading:
// #error insert your used capacitance value here. Currently using 2uF. Delete this line after that
capacitance = 1.E-6; // - insert value here
frequency = 1.E6/(2*pulse);
inductance = 1./(capacitance*frequency*frequency*4.*3.14159*3.14159);//one of my profs told me just do squares like this
inductance *= 1E6; //note that this is the same as saying inductance = inductance*1E6
}
total = total - readings[readIndex]; //Sub the last reading
readings[readIndex] = inductance; //add readings to total
total += readings[readIndex]; //Advance to next pos in array
readIndex = readIndex + 1;
if (readIndex >= numReadings) {
readIndex = 0; //reset array if full
}
average = total / numReadings; // calc the avg
Serial.print("High for uS:");
Serial.print( pulse );
Serial.print("\tfrequency Hz:");
Serial.print( frequency );
Serial.print("\tinductance uH:");
Serial.println( inductance );
Serial.println( average );
delay(10);
// clear display by sending spaces
LCD.write(" ");
LCD.write(" ");
// move cursor to beginning of first line
LCD.write(254);
LCD.write(128);
LCD.print("mH ");
// move cursor to beginning of second line
LCD.write(254);
LCD.write(192);
LCD.print(inductance);
delay(500);
}
