Obstacle Avoiding Robot Will Only Turn Left

i have following code programmed onto arduino uno r3. problem no matter what, chooses turn left. never goes forward, never turns right, never turns around. know leftmotor hooked , working cause if replace if statements in loop command run both motors, both work.

code: [select]


#include <servo.h>

int leftmotor = 2;
int rightmotor = 3;
int leftdistance, rightdistance;
servo pingservo;
long duration;
const int pingpin = 4;
const int dangerdist = 10;

//servo initial position
int pos = 90;

void setup(){
  pingservo.attach(5);
  pinmode(leftmotor, output);
  pinmode(rightmotor, output);
  pingservo.write(pos);
}

void loop(){
  int distancefwd = ping();
  if( distancefwd > dangerdist){
    digitalwrite(leftmotor, high);
    digitalwrite(rightmotor, high);
  }
  else{
    digitalwrite(leftmotor, low);
    digitalwrite(rightmotor, low);
    pingservo.write(45);
    delay(500);
    rightdistance = ping();
    delay(500);
    pingservo.write(135);
    delay(700);
    leftdistance = ping();
    delay(500);
    pingservo.write(pos);
    delay(100);
    comparedistance();
  }
}

void forward(){
  digitalwrite(leftmotor, high);
  digitalwrite(rightmotor, high);
  return;
}

void comparedistance(){
  if(leftdistance > rightdistance){
    digitalwrite(leftmotor, low);
    digitalwrite(rightmotor, high);
    delay(1050);
  }
  else if(rightdistance > leftdistance){
     digitalwrite(leftmotor, high);
     digitalwrite(rightmotor, low);
     delay(1050);
  }
  else{
    digitalwrite(leftmotor, low);
    digitalwrite(rightmotor, high);
    delay(2100);
  }
}

long ping(){
  // send out ping))) signal pulse
  pinmode(pingpin, output);
  digitalwrite(pingpin, low);
  delaymicroseconds(2);
  digitalwrite(pingpin, high);
  delaymicroseconds(5);
  digitalwrite(pingpin, low);
 
  //get duration takes receive echo
  pinmode(pingpin, input);
  duration = pulsein(pingpin, high);
 
  //convert duration distance
  return duration / 79 / 2;
}


what see if print leftdistance , rightdistance ?

code: [select]

 else{
    digitalwrite(leftmotor, low);
    digitalwrite(rightmotor, high);
    delay(2100);
  }
isn't same here

code: [select]

 if(leftdistance > rightdistance){
    digitalwrite(leftmotor, low);
    digitalwrite(rightmotor, high);

Arduino Forum > Using Arduino > Programming Questions > Obstacle Avoiding Robot Will Only Turn Left

arduino