This project creates a smart baby monitor that detects when your baby wakes up and sends an alert to your phone. Unlike traditional audio or video monitors, this system uses a PIR sensor to detect movement in the crib without intrusive cameras or microphones, preserving privacy while still alerting you when the baby is awake.<\/p>\n
Difficulty:<\/strong> Intermediate A PIR sensor is positioned above or near the crib to detect motion. When the baby moves (wakes up), the ESP32 detects the motion and sends a notification to your phone via Blynk or Telegram. A sensitivity adjustment ensures small movements (like breathing) don’t trigger false alerts while larger movements (waking up) do.<\/p>\n Optional features include: a temperature sensor to monitor room temperature, a night light that turns on when motion is detected, and an audio playback module for lullabies.<\/p>\n Mount the PIR sensor above the crib, angled downward to cover only the crib area. For a standard crib, mounting at 1-1.5m height, angled at 45\u00b0, provides coverage of the entire crib.<\/p>\n Adjust the sensitivity potentiometer so that small movements (breathing, turning head) do not trigger, but larger movements (sitting up, standing) do. This may take some trial and error.<\/p>\n This PIR-based baby monitor provides peace of mind without intrusive cameras or constant audio monitoring. You’ll know exactly when your baby wakes up, allowing you to respond promptly while preserving privacy.<\/p>\n","protected":false},"excerpt":{"rendered":" Project Overview This project creates a smart baby monitor that detects when your baby wakes up and sends an alert to your phone. Unlike traditional audio or video monitors, this system uses a PIR sensor to detect movement in the crib without intrusive cameras or microphones, preserving privacy while still alerting you when the baby […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-3914","post","type-post","status-publish","format-standard","hentry","category-projects"],"blocksy_meta":[],"yoast_head":"\r\n
\nEstimated time:<\/strong> 2 hours
\nEstimated cost:<\/strong> $20-30<\/p>\nHow It Works<\/h2>\n
Materials Needed<\/h2>\n
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Blynk Setup<\/h2>\n
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Circuit Diagram<\/h2>\n
Connection Table<\/h3>\n
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Component<\/th>\n Pin<\/th>\n ESP32 Pin<\/th>\n<\/thead>\n \nPIR Sensor<\/th>\n VCC<\/td>\n 3.3V<\/td>\n<\/tr>\n PIR Sensor<\/th>\n GND<\/td>\n GND<\/td>\n<\/tr>\n PIR Sensor<\/th>\n OUT<\/td>\n GPIO 4<\/td>\n<\/tr>\n DHT22<\/th>\n VCC<\/td>\n 3.3V<\/td>\n<\/tr>\n DHT22<\/th>\n GND<\/td>\n GND<\/td>\n<\/tr>\n DHT22<\/th>\n DATA<\/td>\n GPIO 5<\/td>\n<\/tr>\n WS2812B LED<\/th>\n VCC<\/td>\n 5V<\/td>\n<\/tr>\n WS2812B LED<\/th>\n GND<\/td>\n GND<\/td>\n<\/tr>\n WS2812B LED<\/th>\n DATA<\/td>\n GPIO 6<\/td>\n<\/tr>\n Buzzer<\/th>\n Positive<\/td>\n GPIO 7<\/td>\n<\/tr>\n Buzzer<\/th>\n Negative<\/td>\n GND<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Arduino Code (Blynk IoT Platform)<\/h2>\n
\/\/ PIR Baby Monitor with Blynk\n#include <WiFi.h>\n#include <BlynkSimpleEsp32.h>\n#include <DHT.h>\n#include <FastLED.h>\n\n\/\/ Blynk credentials\n#define BLYNK_TEMPLATE_ID \"YourTemplateID\"\n#define BLYNK_TEMPLATE_NAME \"Baby Monitor\"\n#define BLYNK_AUTH_TOKEN \"YourAuthToken\"\n\n\/\/ Wi-Fi credentials\nchar ssid[] = \"YourWiFiSSID\";\nchar pass[] = \"YourWiFiPassword\";\n\n\/\/ Pin definitions\nconst int pirPin = 4;\nconst int dhtPin = 5;\nconst int ledPin = 6;\nconst int buzzerPin = 7;\n\n\/\/ DHT sensor\n#define DHTTYPE DHT22\nDHT dht(dhtPin, DHTTYPE);\n\n\/\/ LED strip\n#define NUM_LEDS 8\nCRGB leds[NUM_LEDS];\nbool nightLightOn = false;\n\n\/\/ Timing\nunsigned long lastAlertTime = 0;\nconst unsigned long alertCooldown = 300000; \/\/ 5 minutes between alerts\nbool motionDetectedFlag = false;\n\nvoid setup() {\n Serial.begin(115200);\n \n pinMode(pirPin, INPUT);\n pinMode(buzzerPin, OUTPUT);\n digitalWrite(buzzerPin, LOW);\n \n \/\/ Initialize LED strip\n FastLED.addLeds<WS2812B, ledPin, GRB>(leds, NUM_LEDS);\n FastLED.setBrightness(64);\n FastLED.clear();\n \n \/\/ Initialize DHT\n dht.begin();\n \n \/\/ Connect to Blynk\n Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);\n \n Serial.println(\"Baby Monitor Ready\");\n Serial.println(\"Waiting 60 seconds for PIR warm-up...\");\n delay(60000);\n}\n\n\/\/ Night light control from Blynk app\nBLYNK_WRITE(V0) {\n nightLightOn = param.asInt();\n if (nightLightOn) {\n \/\/ Soft warm light\n for (int i = 0; i < NUM_LEDS; i++) {\n leds[i] = CRGB(255, 180, 100);\n }\n FastLED.show();\n } else {\n FastLED.clear();\n FastLED.show();\n }\n}\n\nvoid sendAlert() {\n if (millis() - lastAlertTime > alertCooldown) {\n Serial.println(\"Baby waking up! Sending alert...\");\n Blynk.logEvent(\"baby_wakeup\", \"Baby is waking up!\");\n lastAlertTime = millis();\n \n \/\/ Local buzzer alert (soft beep)\n tone(buzzerPin, 1000, 200);\n delay(200);\n tone(buzzerPin, 1500, 200);\n \n \/\/ Turn on night light temporarily\n if (!nightLightOn) {\n for (int i = 0; i < NUM_LEDS; i++) {\n leds[i] = CRGB(255, 180, 100);\n }\n FastLED.show();\n delay(10000); \/\/ 10 seconds\n if (!nightLightOn) {\n FastLED.clear();\n FastLED.show();\n }\n }\n }\n}\n\nvoid readAndSendTemperature() {\n float temp = dht.readTemperature();\n float humidity = dht.readHumidity();\n \n if (!isnan(temp)) {\n Blynk.virtualWrite(V1, temp);\n Blynk.virtualWrite(V2, humidity);\n }\n}\n\nvoid loop() {\n Blynk.run();\n \n bool motion = digitalRead(pirPin) == HIGH;\n \n if (motion && !motionDetectedFlag) {\n motionDetectedFlag = true;\n sendAlert();\n }\n \n if (!motion) {\n motionDetectedFlag = false;\n }\n \n \/\/ Send temperature every 30 seconds\n static unsigned long lastTempRead = 0;\n if (millis() - lastTempRead > 30000) {\n readAndSendTemperature();\n lastTempRead = millis();\n }\n \n delay(100);\n}\n<\/code><\/pre>\nAlternative: Telegram Bot Version (No Blynk Account Needed)<\/h2>\n
\/\/ Telegram Bot Version\n#include <WiFi.h>\n#include <UniversalTelegramBot.h>\n#include <WiFiClientSecure.h>\n\nconst char* ssid = \"YourWiFiSSID\";\nconst char* password = \"YourWiFiPassword\";\nconst char* botToken = \"YourTelegramBotToken\";\nconst char* chatID = \"YourChatID\";\n\nWiFiClientSecure client;\nUniversalTelegramBot bot(botToken, client);\n\nconst int pirPin = 4;\nunsigned long lastAlertTime = 0;\nconst unsigned long alertCooldown = 300000;\n\nvoid setup() {\n Serial.begin(115200);\n pinMode(pirPin, INPUT);\n \n WiFi.begin(ssid, password);\n while (WiFi.status() != WL_CONNECTED) {\n delay(500);\n }\n Serial.println(\"WiFi connected\");\n \n client.setCACert(TELEGRAM_CERTIFICATE_ROOT);\n delay(60000); \/\/ PIR warm-up\n}\n\nvoid sendTelegramAlert() {\n if (millis() - lastAlertTime > alertCooldown) {\n String message = \"Baby is waking up! \ud83d\udc76\";\n bot.sendMessage(chatID, message, \"\");\n lastAlertTime = millis();\n }\n}\n\nvoid loop() {\n bool motion = digitalRead(pirPin) == HIGH;\n if (motion) {\n sendTelegramAlert();\n delay(10000); \/\/ Debounce\n }\n delay(100);\n}\n<\/code><\/pre>\nSensor Placement<\/h2>\n
Crib Placement<\/h3>\n
Adjusting Sensitivity<\/h3>\n
Installation Steps<\/h2>\n
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Project Extensions<\/h2>\n
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Troubleshooting<\/h2>\n
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alertCooldown<\/code>. Adjust PIR sensitivity potentiometer.<\/li>\nSafety Considerations<\/h2>\n
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Conclusion<\/h2>\n