Distance measurement using ultrasonic sensor

Other Hardware Sensors
1

Hi,
Using the ultrasonic module, I was trying to measure distance (water level in a tank). I settled up two ultrasonic sensors (HR-SR04) for getting more accurate data, but I'm getting the same value for the below code. I can't understand why the sensors/modules are providing the same distance even though they are placed at different known distances. I'm using Arduino Mega 2560 device.

const int trigPin1 = 33;
const int echoPin1 = 35;
const int trigPin2 = 32;
const int echoPin2 = 34;

long duration1;
int distance1;
long duration2;
int distance2;

void setup() {
  Serial.begin(9600); 
  pinMode(trigPin1, OUTPUT); 
  pinMode(echoPin1, INPUT); 
  pinMode(trigPin2, OUTPUT); 
  pinMode(echoPin2, INPUT); 
}

void loop() {
  
  digitalWrite(trigPin1, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin1, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin1, LOW);
  duration1 = pulseIn(echoPin1, HIGH);
  distance1 = (duration1 * 0.034 / 2)+1;
  
  digitalWrite(trigPin2, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin2, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin2, LOW);
  duration2 = pulseIn(echoPin2, HIGH);
  distance2 = (duration1 * 0.034 / 2)+1;
  
  Serial.print(distance1); Serial.print(",");
  Serial.print(distance2);
  Serial.println();
  delay (5000);
}
2

Look at duration. You need to be careful with copy and paste.

1 Like
3

Check your code again there is mistake there pls identify it in duration

1 Like
4

In addition to that, I'd put a delay between taking the readings, to allow the echoes of the first ping to decay sufficiently to not cause false readings on the second ping.

1 Like
5

Yes delay can be helpful but including delays resulting in slow proccesing

There are more ways

6

There's already a five second delay between pairs of readings.
I'm talking about 30 to 50 milliseconds

7

In the program delay is for loop not in between for sensor reading

8

Welcome to my ignore list

9

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