Hi Sir,Not sure I understand exactly what you mean by "crack" (Crack in what material and what item, dimensions, etc.) and by "detect".
If you are finding the distance from the transducers to the crack, isn't that sensing it? <== Clearly, I don't understand the setup.
HC-SR04 Ultrasonic Module:If I had to guess, the HCSR04 does not have the sensitivity to detect such a narrow change in distance.
Hi sir,You could try this first, if it doesn't work then you have to turn the direction of transmitters and receiver as cone
View attachment 100761
Source of picture.
Ok sir,You have to comparing the values of flat wall and flaw wall, if the flaw is too small, I don't think it will works properly, because the distance of two components are too far.
View attachment 100805
now as per your Design http://forum.allaboutcircuits.com/threads/arduino-hcsr04-crack-measuring.120902/#post-965902Electric Parameter
Working Voltage-----------------------DC 5 V
Working Current-----------------------15mA
Working Frequency-------------------40Hz
Max Range------------------------------4m
Min Range------------------------------2cm
Measuring Angle----------------------15 degree
Trigger Input Signal------------------10uS TTL pulse
Echo Output Signal Input-----------TTL lever signal and the range in proportion
I thing that should solve the problem
If this method didn't works then you have to adjust the angles of two pipes, when you try it at many angles, but it still didn't works as your wish then you need to take the transmitter and receiver away from the pcb and put their direction as cone, you have to make sure they have a small angles maybe 10~20° between them, you need to adjust the angle to check which angle has the best effective.Ok sir,
is this will miss behave because of this cone shape ?
i will try it and revert back to u sir
Sir,Hi dear all,
The Ultrasonic ranging module HC - SR04 provides 2cm - 400cm non-contact measurement function, the ranging accuracy can reach to 3mm (i.e. 0.3 cm)
Using IO trigger for at least 10us high level signal,
The Module automatically sends eight 40 kHz and detect whether there is a pulse signal back...
now as per your Design http://forum.allaboutcircuits.com/threads/arduino-hcsr04-crack-measuring.120902/#post-965902
the main thing is your Moving Speed the Stationary parameters is (as per the datasheet) is 10μs ( Trigger Input Signal------------------10uS TTL pulse ) and that to at an Angel of 15°
so now you have to adjust your Speed to DETECT the CRACK in the RAIL
I thing that should solve the problem
/*
HC-SR04 Ping distance sensor]
VCC to arduino 5v GND to arduino GND
Echo to Arduino pin 13 Trig to Arduino pin 12
Red POS to Arduino pin 11
Green POS to Arduino pin 10
560 ohm resistor to both LED NEG and GRD power rail
More info at: [URL]http://goo.gl/kJ8Gl[/URL]
Original code improvements to the Ping sketch sourced from Trollmaker.com
Some code and wiring inspired by [URL]http://en.wikiversity.org/wiki/User:Dstaub/robotcar[/URL]
*/
#define trigPin 13
#define echoPin 12
#define led 11
#define led2 10
void setup() {
Serial.begin (9600);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
pinMode(led, OUTPUT);
pinMode(led2, OUTPUT);
}
void loop() {
long duration, distance;
digitalWrite(trigPin, LOW); // Added this line
delayMicroseconds(2); // Added this line
digitalWrite(trigPin, HIGH);
// delayMicroseconds(1000); - Removed this line
delayMicroseconds(10); // Added this line
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
distance = (duration/2) / 29.1;
if (distance < 4) { // This is where the LED On/Off happens
digitalWrite(led,HIGH); // When the Red condition is met, the Green LED should turn off
digitalWrite(led2,LOW);
}
else {
digitalWrite(led,LOW);
digitalWrite(led2,HIGH);
}
if (distance >= 200 || distance <= 0){
Serial.println("Out of range");
}
else {
Serial.print(distance);
Serial.println(" cm");
}
delay(500);
}
by Jake Hertz
by Duane Benson
by Jake Hertz