Interactive Sensor Hub: An Arduino Project with 4 Smart Sensor Modes

1#include <IRremote.hpp>  // Use IRremote.hpp in new versions
2#include <LiquidCrystal.h>
3
4
5#define PHOTORESISTOR_PIN A0
6
7#define SOUND_SENSOR_PIN A5
8
9#define IR_RECEIVE_PIN 5
10
11
12#define ECHO_PIN 3       
13#define TRIGGER_PIN 4 
14
15#define IR_BUTTON_1 12
16#define IR_BUTTON_2 24
17#define IR_BUTTON_3 94
18#define IR_BUTTON_4 8
19#define IR_BUTTON_PLAY 64
20
21#define LED_RED 12
22#define LED_YELLOW 11    
23#define LED_GREEN 10 
24
25#define LCD_RS_PIN A1
26#define LCD_E_PIN A2
27#define LCD_D4_PIN 6
28#define LCD_D5_PIN 7
29#define LCD_D6_PIN 8
30#define LCD_D7_PIN 9
31
32#define BUZZER 13
33#define BUTTON 2
34
35
36LiquidCrystal lcd(LCD_RS_PIN, LCD_E_PIN, LCD_D4_PIN, LCD_D5_PIN, LCD_D6_PIN, LCD_D7_PIN); // Initializes LCD with given pins
37
38unsigned long last_time_ultrasonic_trigger = millis(); 
39unsigned long ultrasonic_trigger_delay = 500;          
40volatile unsigned long pulse_in_begin;
41volatile unsigned long pulse_in_end;
42volatile bool new_distance_available = false;
43
44unsigned long previous_time_buzz = millis();
45
46int current_mode = 0;  // 0 = idle, 1 = Button 1, 2 = Button 2, etc.
47
48int new_distance = 0;
49int old_distance = 0;
50
51float km = 0;
52
53
54void trigger_ultrasonic_sensor(){
55  digitalWrite(TRIGGER_PIN, LOW);  
56  delayMicroseconds(2);             
57  digitalWrite(TRIGGER_PIN, HIGH); 
58  delayMicroseconds(10);           
59  digitalWrite(TRIGGER_PIN, LOW);  
60}
61
62// Function to calculate the distance measured by the ultrasonic sensor
63int get_distance()
64{
65  double duration_micros = pulse_in_end - pulse_in_begin;
66  double distance = duration_micros / 58.0;
67  return distance;
68}
69
70// Interrupt service routine (ISR) for detecting the echo pulse
71void echo_pin_interrupt()
72{
73  if (digitalRead(ECHO_PIN) == HIGH) {
74    pulse_in_begin = micros();
75  }
76  else {
77    pulse_in_end = micros();
78    new_distance_available = true;
79  }
80}
81
82int buzzer_state = LOW;
83
84
85void setup() {
86  Serial.begin(115200);
87  IrReceiver.begin(IR_RECEIVE_PIN);  // Start the IR receiver
88
89  pinMode(LED_RED, OUTPUT);
90  pinMode(LED_YELLOW, OUTPUT);
91  pinMode(LED_GREEN, OUTPUT);
92
93  pinMode(LED_RED, OUTPUT);
94  pinMode(LED_YELLOW, OUTPUT);
95  pinMode(LED_GREEN, OUTPUT);
96  pinMode(ECHO_PIN, INPUT);  
97
98  pinMode(TRIGGER_PIN, OUTPUT);
99  pinMode(BUZZER, OUTPUT);
100
101  lcd.begin(16, 2); // For a 16x2 LCD 
102
103  attachInterrupt(digitalPinToInterrupt(ECHO_PIN), echo_pin_interrupt, CHANGE);
104
105  pinMode(SOUND_SENSOR_PIN, INPUT);
106
107  
108}
109
110void loop() {
111  unsigned long time_now = millis();
112
113  
114
115  if (IrReceiver.decode()) {
116    unsigned long value = IrReceiver.decodedIRData.command;
117
118    if (value == IR_BUTTON_1) {
119      current_mode = 1;
120    }
121    else if (value == IR_BUTTON_2) {
122      current_mode = 2;
123    }
124    else if (value == IR_BUTTON_3) {
125      current_mode = 3;
126    }
127    else if (value == IR_BUTTON_4) {
128      current_mode = 4;
129    }
130    else if (value == IR_BUTTON_PLAY) {
131      current_mode = 5;
132    }
133
134    IrReceiver.resume();  // Ready for next signal
135  }
136
137  // Button 1 logic runs continuously if current_mode is 1
138  if (current_mode == 1) {
139    
140    if (time_now - last_time_ultrasonic_trigger > ultrasonic_trigger_delay) {
141      last_time_ultrasonic_trigger += ultrasonic_trigger_delay; 
142      trigger_ultrasonic_sensor();
143    }
144
145    if (new_distance_available) {
146      new_distance_available = false;
147      int distance = get_distance();
148
149      old_distance =  new_distance;
150      new_distance = distance;
151
152      if (old_distance > new_distance){
153         km = (old_distance - new_distance) * 2.0 / 100000 * 3600;
154         Serial.println(km);
155      }
156      else {   
157         km = (new_distance - old_distance) * 2.0 / 100000 * 3600;
158         Serial.println(km);
159      }
160      
161      Serial.println(distance);
162      lcd.setCursor(0, 0);
163      lcd.print("                "); // Clear line
164      lcd.setCursor(0, 0);
165      lcd.print("distance:  ");
166      lcd.print(distance);
167      lcd.print("CM");
168  
169      if (old_distance - new_distance > 5){
170        lcd.setCursor(0, 1);
171        lcd.print("                "); // Clear line
172        lcd.setCursor(0, 1);
173        lcd.print("coming   "); lcd.print(km); lcd.print("Km/h");
174      }
175      else if(new_distance - old_distance > 5){
176        lcd.setCursor(0, 1);
177        lcd.print("                "); // Clear line
178        lcd.setCursor(0, 1);
179        lcd.print("going    "); lcd.print(km); lcd.print("Km/h");
180        
181      }else{
182        lcd.setCursor(0, 1);
183        lcd.print("                "); // Clear line
184        lcd.setCursor(0, 1);
185        lcd.print("stationary");        
186      }
187    }
188    }
189
190  // Button 2 placeholder
191else if (current_mode == 2) {
192  if (time_now - last_time_ultrasonic_trigger > ultrasonic_trigger_delay) {
193    last_time_ultrasonic_trigger += ultrasonic_trigger_delay;
194    trigger_ultrasonic_sensor();
195  }
196
197  if (new_distance_available) {
198    new_distance_available = false;
199    int distance = get_distance();
200    Serial.println(distance);
201
202    if (distance > 0 && distance <= 50) {
203      // Red light + fast buzzer (every 250 ms)
204      if (time_now - previous_time_buzz > 250) {
205        digitalWrite(LED_RED, HIGH);
206        digitalWrite(LED_YELLOW, LOW);
207        digitalWrite(LED_GREEN, LOW);
208
209        buzzer_state = !buzzer_state;
210        digitalWrite(BUZZER, buzzer_state);
211
212        previous_time_buzz = time_now;
213
214        lcd.clear();
215        lcd.print("close");
216      }
217    }
218    else if (distance > 50 && distance <= 150) {
219      // Yellow light + medium buzzer (every 500 ms)
220      if (time_now - previous_time_buzz > 500) {
221        digitalWrite(LED_RED, LOW);
222        digitalWrite(LED_YELLOW, HIGH);
223        digitalWrite(LED_GREEN, LOW);
224
225        buzzer_state = !buzzer_state;
226        digitalWrite(BUZZER, buzzer_state);
227
228        previous_time_buzz = time_now;
229
230        lcd.clear();
231        lcd.print("medium");
232      }
233    }
234    else if (distance > 150) {
235      // Green light, no buzzer
236      digitalWrite(LED_RED, LOW);
237      digitalWrite(LED_YELLOW, LOW);
238      digitalWrite(LED_GREEN, HIGH);
239
240      digitalWrite(BUZZER, LOW); // Turn buzzer off
241      buzzer_state = LOW;
242
243      lcd.clear();
244      lcd.print("far");
245    }
246  }
247}
248  // Button 3 placeholder
249else if (current_mode == 3) {
250  Serial.println("Mode 3 active");
251
252  int light = analogRead(PHOTORESISTOR_PIN);
253  Serial.print("Light: ");
254  Serial.println(light);
255
256  if (light < 300) {
257    digitalWrite(LED_RED, HIGH);  // Turn on RED LED if dark
258  } else {
259    digitalWrite(LED_RED, LOW);
260  }
261
262  int brightness = 255 - light / 4;
263  analogWrite(LED_GREEN, brightness);  // PWM works on pin 10 (Uno)
264
265  lcd.setCursor(0, 0);
266  lcd.print("Light:");
267  lcd.print(light);
268  lcd.print("   ");
269
270  lcd.setCursor(0, 1);
271  lcd.print("Green PWM:");
272  lcd.print(brightness);
273  lcd.print("   ");
274}
275
276
277  // Button 4 placeholder
278else if (current_mode == 4) {
279  static bool leds_on = false;
280  static unsigned long last_clap_time = 0;
281  static bool last_state = LOW;
282
283  int sound = digitalRead(A5);  // digital pin connected to DO pin
284  Serial.println(sound);        // debug - watch it go HIGH when clapping
285
286  unsigned long now = millis();
287
288  if (sound == HIGH && last_state == LOW && (now - last_clap_time > 400)) {
289    leds_on = !leds_on;
290    last_clap_time = now;
291
292    digitalWrite(LED_RED, leds_on ? HIGH : LOW);
293    digitalWrite(LED_YELLOW, leds_on ? HIGH : LOW);
294    digitalWrite(LED_GREEN, leds_on ? HIGH : LOW);
295  }
296
297  last_state = sound;  // remember the last value
298}
299
300}