วิธีต่อ Arduino กับ Ping Ultrasonic Sensor (HC-SR04)
รูป Ping Ultrasonic Sensor (HC-SR04)
ตัวอย่างโค้ด
/*
HC-SR04 Ping distance sensor:
VCC to arduino 5v
GND to arduino GND
Echo to Arduino pin 7
Trig to Arduino pin 8
This sketch originates from Virtualmix: http://goo.gl/kJ8Gl
Has been modified by Winkle ink here: http://winkleink.blogspot.com.au/2012/05/arduino-hc-sr04-ultrasonic-distance.html
And modified further by ScottC here: http://arduinobasics.blogspot.com/
on 10 Nov 2012.
*/
#define echoPin 7 // Echo Pin
#define trigPin 8 // Trigger Pin
#define LEDPin 13 // Onboard LED
long duration, inches, cm;
int maximumRange = 100; // Maximum range needed
int minimumRange = 10; // Minimum range needed
void setup() {
Serial.begin (9600);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
pinMode(LEDPin, OUTPUT); // Use LED indicator (if required)
}
void loop() {
/* The following trigPin/echoPin cycle is used to determine the
distance of the nearest object by bouncing soundwaves off of it. */
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
inches = microsecondsToInches(duration);
cm = microsecondsToCentimeters(duration);
Serial.print(inches);
Serial.print("in, ");
Serial.print(cm);
Serial.print("cm");
Serial.println();
if (cm >= maximumRange || cm <= minimumRange){
/* Send a negative number to computer and Turn LED ON
to indicate "out of range" */
digitalWrite(LEDPin, HIGH);
}
else {
/* Send the distance to the computer using Serial protocol, and
turn LED OFF to indicate successful reading. */
digitalWrite(LEDPin, LOW);
}
//Delay 50ms before next reading.
delay(1000);
}
long microsecondsToInches(long microseconds)
{
// According to Parallax's datasheet for the PING))), there are
// 73.746 microseconds per inch (i.e. sound travels at 1130 feet per
// second). This gives the distance travelled by the ping, outbound
// and return, so we divide by 2 to get the distance of the obstacle.
// See: http://www.parallax.com/dl/docs/prod/acc/28015-PING-v1.3.pdf
return microseconds / 74 / 2;
}
long microsecondsToCentimeters(long microseconds)
{
// The speed of sound is 340 m/s or 29 microseconds per centimeter.
// The ping travels out and back, so to find the distance of the
// object we take half of the distance travelled.
return microseconds / 29 / 2;
}
ความรู้จากบทความนี้สามารถนำไปประยุกต์ใช้- สร้างหุ่นยนต์ด้วย Arduino ตอนที่ 1 ฝึกให้หุ่นยนต์หลบหลีกสิ่งกีดขวาง
ที่มา
ไม่มีความคิดเห็น:
แสดงความคิดเห็น