Hi,
I bought an ultrasonic sensor from Robotshop several days ago. The part name was RB-Nex-21.
I’ve been trying to check whether it works with Arduino or not but have not been able to figure out how to operate it.
I am just using the typical Arduino 4-pin ultrasonic sensor code that I found online, which looks like below:
[code]/* HC-SR04 Sensor
This sketch reads a HC-SR04 ultrasonic rangefinder and returns the
distance to the closest object in range. To do this, it sends a pulse
to the sensor to initiate a reading, then listens for a pulse
to return. The length of the returning pulse is proportional to
the distance of the object from the sensor.
The circuit:
- VCC connection of the sensor attached to +5V
- GND connection of the sensor attached to ground
- TRIG connection of the sensor attached to digital pin 2
- ECHO connection of the sensor attached to digital pin 4
Original code for Ping))) example was created by David A. Mellis
Adapted for HC-SR04 by Tautvidas Sipavicius
This example code is in the public domain.
*/
const int trigPin = 2;
const int echoPin = 4;
long duration, inches, cm;
void setup() {
// initialize serial communication:
Serial.begin(9600);
long duration, inches, cm;
// The sensor is triggered by a HIGH pulse of 10 or more microseconds.
// Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
// pinMode(trigPin, OUTPUT);
// Read the signal from the sensor: a HIGH pulse whose
// duration is the time (in microseconds) from the sending
// of the ping to the reception of its echo off of an object.
// pinMode(echoPin, INPUT);
}
void loop()
{
// establish variables for duration of the ping,
// and the distance result in inches and centimeters:
pinMode(trigPin, OUTPUT);
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
pinMode(echoPin, INPUT);
duration = pulseIn(echoPin, HIGH);
// convert the time into a distance
inches = microsecondsToInches(duration);
cm = microsecondsToCentimeters(duration);
Serial.print(duration);
Serial.print(inches);
Serial.print("in, ");
Serial.print(cm);
Serial.print(“cm”);
Serial.println();
delay(100);
}
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;
}
[/code]
I connected a pin labeled ‘+’ to 5V source on Arduino, ‘-’ to Ground, ‘A’ to pin 2, and ‘B’ to pin 4.
Since I wasn’t sure which pins are for trigger and echo, I switched them to see if that makes the sensor work, but no success.
Also, I am curious what the jumper pins on the side of each ports are.
It would be greatly appreciated if someone out there can help me out on this issue. It should be a simple glitch either in the wiring scheme or the code that is hindering me from operating this sensor.
Thanks a lot!