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Object following Robot

Hello there all of you…I have built a robot using arduino uno, a pixy2 cam, a L298N motor controller and 2 DC motors in order to track objects of different colors in real time…The robot is working but not perfectly…I will appreciate if you have any recommendations for improvement of the code…and also if you can help me attach the pan tilt in the code if this will help the robot.

#include <PIDLoop.h> //###############################################
#include <Pixy2.h> //IMPORTING LIBRARIES
Pixy2 pixy; //###############################################

////////////////////////////////////////////////////////

// ENA IN1 IN2 IN3 IN4 ENB
int myPins[6] = {5, 6, 7, 8, 9, 10}; //VARIABLES DECLARATION. MOTOR CONTROLLER CONNECTED TO PINS 5,6,7,8,9,10. eACH OF THEM REPRESENT THER PARTICULAR ORDER WHOCH IS ENABLE INPUT 1,2,3,4 AND ENABLE

float deadZone = 0.15; //dead zone tha defines where the object will not move at all equals to 15%
int baseSpeed = 250; // base speed that the robot will run

////////////////////////////////////////////////////////

int cont = 0;
int signature, x, y, width, height;
float cx, cy, area;

void setup() {
Serial.begin(9600);
Serial.print(“Starting…\n”);
pixy.init();
for (int i = 0; i < 6; i++) {
pinMode(myPins[i], OUTPUT); //declaring all pins as output using a for loop
}
}

void loop() {
float turn = pixyCheck(); //checking the value of the turn. how much deviation we have from the center using the pixy check function
if (turn > -deadZone && turn < deadZone) { //applying deadzone
turn = 0;
}
if (turn < 0) {
moveRobot(170, -80); //deciding how much to move the robot
}
else if (turn > 0) { //looking if the turn is positive or negative and moving, otherwise keep going forward
moveRobot(-80, 170);
}
else {
moveRobot(70, 70); //takes the value of the left speed and the right speed
}
delay(1);
}

float pixyCheck() {
static int i = 0;
int j;
uint16_t blocks;
char buf[32];
// grab blocks!
blocks = pixy.ccc.getBlocks();

// If there are detect blocks, print them!
if (blocks)
{
signature = pixy.ccc.blocks[0].m_signature;
height = pixy.ccc.blocks[0].m_height; //height of the object
width = pixy.ccc.blocks[0].m_width; //width of the object
x = pixy.ccc.blocks[0].m_x;//x value of the object
y = pixy.ccc.blocks[0].m_y;//y value of the object
cx = (x + (width / 2)); //center x position
cy = (y + (height / 2)); //center y position
cx = mapfloat(cx, 0, 320, -1, 1); // aplying normalization. If value is from 0-320 change from -1 to 1. This helps in the computation
cy = mapfloat(cy, 0, 200, 1, -1);
area = width * height;

        //Serial.print("sig: ");
        //Serial.print(signature);
        //Serial.print(" x:");
        //Serial.print(x);
        //Serial.print(" y:");
        //Serial.print(y);
        //Serial.print(" width: ");
        //Serial.print(width);
        //Serial.print(" height: ");
        //Serial.print(height);
       //Serial.print(" cx: ");
        //Serial.print(cx);
        //Serial.print(" cy: ");
        //Serial.println(cy);

}
else {
cont += 1;
if (cont == 100) {
cont = 0;
cx = 0;
}
}
return cx; //sending back the x location to tell our robot to turn in a particular direction whether is positive or negative
}

float mapfloat(long x, long in_min, long in_max, long out_min, long out_max)
{
return (float)(x - in_min) * (out_max - out_min) / (float)(in_max - in_min) + out_min;
}

void moveRobot(int leftSpeed, int rightSpeed)
{
if (leftSpeed >= 0) {
digitalWrite(myPins[1], 0);
digitalWrite(myPins[2], 1);
}
else {
digitalWrite(myPins[1], 1);
digitalWrite(myPins[2], 0);
}

if (rightSpeed >= 0) {
digitalWrite(myPins[3], 0);
digitalWrite(myPins[4], 1);
}
else {
digitalWrite(myPins[3], 1);
digitalWrite(myPins[4], 0);
}

analogWrite(myPins[0], abs(leftSpeed));
analogWrite(myPins[5], abs(rightSpeed));
}

Hi, could you please indicate more specifically what’s not working?

Thanks,
Jesse

Hello, The problem basically is that the camera often loses the object and that the robot is quite slow comparing to other I have seen.

Hello,
Regarding Pixy losing the object, this page has some good information:

https://docs.pixycam.com/wiki/doku.php?id=wiki:v2:pixy_is_detecting_the_wrong_objects

Use Pixy’s LED to help debug when it’s losing the object. (The LED will illuminate when it detects an object. The color will be the same color as the detected object.) Sometimes the robot’s movement can cause Pixy to lose the object.

Hope this helps :slight_smile:

Edward