Servo & Ultrasonic sensor

Using Arduino Motors, Mechanics, Power and CNC
1

Hey there fellas:

I'm trying to make a simple 'robot' which consists of an ultrasonic sensor sitting on top of a servo.

The program is simple as well: Read the data from the sensor, move the servo accordingly.

The problem is my servo doesn't move fluently. It "hangs" a bit then moves to the new angle. It has a 1 second interval. I can also see this interval from the LED that is attached to the PING Ultrasonic Sensor. This effect also seen from the serial monitor. (The values go down continuously for a while and then they hang for a second.)

When i remove the data cable of the servo, everything goes back to normal flow.

Here's my code:

#include <Servo.h> 

Servo myservo;  // create servo object to control a servo 
// a maximum of eight servo objects can be created 

long pos = 0;    // variable to store the servo position 
int pingPin = 2;
int duration;
int dist;

void setup() 
{ 
  Serial.begin(9600);
  myservo.attach(9);  // attaches the servo on pin 9 to the servo object 
  myservo.write(90);              // tell servo to go to position in variable 'pos' 

} 


void loop() 
{ 
  dist = distanceCm();
  Serial.print(duration);
  Serial.print(" mapped: ");
  Serial.print(dist);
  Serial.println();
  if (duration > 0)     //avoid the 0 returns
  {
    myservo.write(dist);              
    delay(50);
  }

} 

int distanceCm()
{
  pinMode(pingPin, OUTPUT);
  digitalWrite(pingPin, LOW);
  delayMicroseconds(2);
  digitalWrite(pingPin, HIGH);
  delayMicroseconds(5);
  digitalWrite(pingPin, LOW);
  pinMode(pingPin, INPUT);
  duration = pulseIn(pingPin, HIGH);
  delay(100); 
  return map(duration,150,2600,45,75); 
}

Thanks for the help.

2

Your problem is most likely related to how you are talking to the ulstrasonic sensor. Look at the NewPing thread in the sensor subforum, I would suggest using that library to talk to the sensor.

3

crispy:
Your problem is most likely related to how you are talking to the ulstrasonic sensor. Look at the NewPing thread in the sensor subforum, I would suggest using that library to talk to the sensor.

It was indeed. Thanks for the help =)