1.  
2. import RPi.GPIO as GPIO
3. import time
4. import pygame
5.  
6. # Configure GPIO pins for sensors
7. ENTER_TRIG_PIN = 23
8. ENTER_ECHO_PIN = 24
9. EXIT_TRIG_PIN = 5
10. EXIT_ECHO_PIN = 6
11.  
12. # Configure GPIO pin for relay (LED strip)
13. RELAY_PIN = 17
14.  
15. # Initialize GPIO settings
16. GPIO.setmode(GPIO.BCM)
17. GPIO.setup(ENTER_TRIG_PIN, GPIO.OUT)
18. GPIO.setup(ENTER_ECHO_PIN, GPIO.IN)
19. GPIO.setup(EXIT_TRIG_PIN, GPIO.OUT)
20. GPIO.setup(EXIT_ECHO_PIN, GPIO.IN)
21. GPIO.setup(RELAY_PIN, GPIO.OUT)
22.  
23. # Initialize pygame for audio playback
24. pygame.init()
25. pygame.mixer.init()
26.  
27. # Set up audio file
28. audio_file = "music.mp3"  # Replace with your audio file
29.  
30. # Function to play audio
31. def play_audio():
32.     pygame.mixer.music.load(audio_file)
33.     pygame.mixer.music.play()
34.  
35. # Function to stop audio
36. def stop_audio():
37.     pygame.mixer.music.stop()
38.  
39. # Function to control LED strip
40. def control_led_strip(state):
41.     GPIO.output(RELAY_PIN, state)
42.  
43. def measure_distance(trig_pin, echo_pin, num_readings=5):
44.     distances = []
45.  
46.     for _ in range(num_readings):
47.         GPIO.output(trig_pin, True)
48.         time.sleep(0.00001)
49.         GPIO.output(trig_pin, False)
50.  
51.         pulse_start = time.time()
52.         pulse_end = time.time()
53.  
54.         while GPIO.input(echo_pin) == 0:
55.             pulse_start = time.time()
56.  
57.         while GPIO.input(echo_pin) == 1:
58.             pulse_end = time.time()
59.  
60.         pulse_duration = pulse_end - pulse_start
61.         distance = pulse_duration * 17150  # Speed of sound = 34300 cm/s
62.         distances.append(distance)
63.  
64.     avg_distance = sum(distances) / num_readings
65.     return avg_distance
66.  
67. try:
68.     people_inside = 0  # Counter for people inside the room
69.     entry_cooldown = False  # Flag to prevent rapid multiple entries
70.     exit_cooldown = False  # Flag to prevent rapid multiple exits
71.  
72.     while True:
73.         enter_distance = measure_distance(ENTER_TRIG_PIN, ENTER_ECHO_PIN, num_readings=5)
74.         print("measuring enter distance", enter_distance)
75.         exit_distance = measure_distance(EXIT_TRIG_PIN, EXIT_ECHO_PIN, num_readings=5)
76.         print("measuring exit distance", exit_distance)
77.        
78.         # Detecting if someone is within 30 cm range for entry
79.         if enter_distance < 30 and not entry_cooldown:
80.             people_inside += 1
81.             entry_cooldown = True
82.             time.sleep(2)  # Entry cooldown period, adjust as needed
83.  
84.         # Detecting if someone is within 30 cm range for exit
85.         if exit_distance < 30 and people_inside > 0 and not exit_cooldown:
86.             people_inside -= 1
87.             exit_cooldown = True
88.             time.sleep(2)  # Exit cooldown period, adjust as needed
89.        
90.         print(people_inside)
91.  
92.         if people_inside > 0:
93.             print("people present")
94. #             play_audio()
95. #             control_led_strip(GPIO.HIGH)
96.         else:
97.             print("no one present")
98. #             stop_audio()
99. #             control_led_strip(GPIO.LOW)
100.  
101.         if not (enter_distance < 30):
102.             entry_cooldown = False
103.  
104.         if not (exit_distance < 30):
105.             exit_cooldown = False
106.  
107. except KeyboardInterrupt:
108.     GPIO.cleanup()
109.     pygame.mixer.quit()
110.