Lane-following-by-color-detection-bot-using-respberry-pi-and-open-cv

from gpiozero import PWMOutputDevice

from picamera2 import Picamera2

import cv2

import numpy as np

import time

=== Motor Setup ===

left_motor_forward = PWMOutputDevice(24)

left_motor_backward = PWMOutputDevice(23)

right_motor_forward = PWMOutputDevice(27)

right_motor_backward = PWMOutputDevice(22)

def stop():

left_motor_forward.value = 0

left_motor_backward.value = 0

right_motor_forward.value = 0

right_motor_backward.value = 0

#time.sleep(2)

def forward():

left_motor_forward.value = 0.3

right_motor_forward.value = 0.3

left_motor_backward.value = 0

right_motor_backward.value = 0

def instant_left():

#time.sleep(2)

left_motor_forward.value = 0

left_motor_backward.value = 0

right_motor_forward.value = 0.3

right_motor_backward.value = 0

#time.sleep(1)

def instant_right():

left_motor_forward.value = 0.3

left_motor_backward.value = 0

right_motor_forward.value = 0

right_motor_backward.value = 0.3

=== Color Detection ===

def detect_color(frame):

hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)

Green color (instant left)

lower_green = np.array([36, 85, 70])

upper_green = np.array([86, 255, 255])

mask_green = cv2.inRange(hsv, lower_green, upper_green)

Red color (instant right)

lower_red = np.array([45, 103, 100]) upper_red = np.array([180, 255, 255]) mask_red = cv2.inRange(hsv, lower_red, upper_red) if cv2.countNonZero(mask_green) > 500: return "green" elif cv2.countNonZero(mask_red) > 500: return "red" else: return "none"

=== Camera Setup ===

picam2 = Picamera2() picam2.configure(picam2.create_preview_configuration(main={"format": "RGB888", "size": (1280, 720)})) picam2.start() time.sleep(2) try: while True: frame = picam2.capture_array() frame = cv2.resize(frame, (960, 720)) # Resize for clearer window roi = frame[480:720, :] # Bottom part for line tracking hsv = cv2.cvtColor(roi, cv2.COLOR_BGR2HSV) lower_black = np.array([0, 0, 0]) upper_black = np.array([179, 255, 103]) mask_black = cv2.inRange(hsv, lower_black, upper_black) M = cv2.moments(mask_black) color = detect_color(roi) if color == "green": instant_left() time.sleep(1) elif color == "red": instant_right() elif M["m00"] != 0: cx = int(M["m10"] / M["m00"]) cy = int(M["m01"] / M["m00"])

Draw a blue dot at the center of the black line on the full frame

cv2.circle(frame, (cx, cy + 480), 5, (255, 0, 0), -1) if cx < 350: instant_left() elif cx > 610:

instant_right()

else:

forward()

else:

time.sleep(1)

stop()

cv2.imshow("Line & Color Tracking", frame)

if cv2.waitKey(1) == ord('q'):

break

except KeyboardInterrupt:

print("Stopped by user.")

finally:

stop()

cv2.destroyAllWindows()