智能家居控制系统

基于ESP32的智能家居控制系统，支持远程控制家电、温湿度监测和手机APP联动。

项目简介

智能家居控制系统是一个完整的物联网解决方案，通过ESP32作为核心控制节点，实现对家中电器的智能化控制。

系统架构

                        ┌─────────────┐
                        │  Cloud Server│
                        │   (MQTT)     │
                        └──────┬──────┘
                               │
        ┌──────────────────────┼──────────────────────┐
        │                      │                      │
        ▼                      ▼                      ▼
┌───────────────┐    ┌───────────────┐    ┌───────────────┐
│  ESP32节点1   │    │  ESP32节点2   │    │  ESP32节点3   │
│  (客厅)        │    │  (卧室)        │    │  (厨房)        │
└───────┬───────┘    └───────┬───────┘    └───────┬───────┘
        │                    │                    │
        ▼                    ▼                    ▼
┌───────────────┐    ┌───────────────┐    ┌───────────────┐
│ 继电器/传感器  │    │ 继电器/传感器  │    │ 继电器/传感器  │
└───────────────┘    └───────────────┘    └───────────────┘

硬件清单

设备	数量	说明
ESP32 DevKit	3	主控芯片
继电器模块	6	5V单路继电器
DHT22	3	温湿度传感器
HC-SR501	2	人体红外感应
BH1750	3	光照传感器
电源模块	3	5V 2A

功能特性

• 远程开关控制
• 温湿度监测
• 定时任务
• 手机APP联动
• 场景模式
• 能耗统计

核心代码

1. ESP32主程序

#include <WiFi.h>
#include <PubSubClient.h>
#include <DHT.h>

#define DHTPIN 4
#define DHTTYPE DHT22

const char* ssid = "YourWiFi";
const char* password = "YourPassword";
const char* mqtt_server = "broker.emqx.io";

DHT dht(DHTPIN, DHTTYPE);
WiFiClient espClient;
PubSubClient client(espClient);

// 继电器引脚
const int relayPins[] = {5, 18, 19, 21, 22, 23};
bool relayState[] = {false, false, false, false, false, false};

void setup_wifi() {
  delay(10);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }
}

void callback(char* topic, byte* payload, unsigned int length) {
  char message[length + 1];
  for (int i = 0; i < length; i++) {
    message[i] = payload[i];
  }
  message[length] = '\0';
  
  // 解析JSON命令
  if (strcmp(topic, "home/relay/set") == 0) {
    int pin = message[0] - '0';
    bool state = message[2] == '1';
    digitalWrite(relayPins[pin], state ? HIGH : LOW);
    relayState[pin] = state;
  }
}

void reconnect() {
  while (!client.connected()) {
    if (client.connect("ESP32Client")) {
      client.subscribe("home/relay/set");
      client.subscribe("home/sensor/get");
    } else {
      delay(5000);
    }
  }
}

void publishSensors() {
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  
  char payload[50];
  sprintf(payload, "{\"temp\":%.1f,\"humid\":%.1f}", t, h);
  client.publish("home/sensor/data", payload);
}

void setup() {
  Serial.begin(115200);
  dht.begin();
  
  for (int i = 0; i < 6; i++) {
    pinMode(relayPins[i], OUTPUT);
  }
  
  setup_wifi();
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();
  
  static unsigned long lastMsg = 0;
  if (millis() - lastMsg > 5000) {
    lastMsg = millis();
    publishSensors();
  }
}

2. Node.js后端服务

// server/index.js
const mqtt = require('mqtt');
const express = require('express');
const mongoose = require('mongoose');
const cors = require('cors');

const app = express();
app.use(cors());
app.use(express.json());

const client = mqtt.connect('mqtt://broker.emqx.io:1883');

// 设备状态管理
const deviceStates = new Map();

// MQTT消息处理
client.on('connect', () => {
  console.log('MQTT Connected');
  client.subscribe('home/#');
});

client.on('message', (topic, message) => {
  if (topic === 'home/sensor/data') {
    const data = JSON.parse(message.toString());
    // 存储到数据库
    saveSensorData(data);
  }
});

// REST API
app.get('/api/devices', (req, res) => {
  res.json(Array.from(deviceStates.entries()));
});

app.post('/api/control', (req, res) => {
  const { device, state } = req.body;
  client.publish('home/relay/set', `${device}:${state ? 1 : 0}`);
  res.json({ success: true });
});

app.get('/api/history', async (req, res) => {
  // 返回历史数据
  const data = await getSensorHistory();
  res.json(data);
});

app.listen(3000, () => {
  console.log('Server running on port 3000');
});

3. React Native APP

// App.js
import React, { useState, useEffect } from 'react';
import { View, Text, Switch, FlatList, TouchableOpacity, StyleSheet } from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';

const API_URL = 'http://your-server:3000/api';

export default function App() {
  const [devices, setDevices] = useState([]);
  const [sensors, setSensors] = useState({ temp: 0, humid: 0 });

  useEffect(() => {
    fetchDevices();
    // 定时刷新传感器数据
    const interval = setInterval(fetchSensors, 5000);
    return () => clearInterval(interval);
  }, []);

  const fetchDevices = async () => {
    const res = await fetch(`${API_URL}/devices`);
    const data = await res.json();
    setDevices(data);
  };

  const fetchSensors = async () => {
    const res = await fetch(`${API_URL}/sensors`);
    const data = await res.json();
    setSensors(data);
  };

  const toggleDevice = async (deviceId, currentState) => {
    await fetch(`${API_URL}/control`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ device: deviceId, state: !currentState })
    });
    fetchDevices();
  };

  const renderDevice = ({ item }) => (
    <View style={styles.deviceItem}>
      <Text style={styles.deviceName}>设备 {item[0]}</Text>
      <Switch
        value={item[1]}
        onValueChange={() => toggleDevice(item[0], item[1])}
      />
    </View>
  );

  return (
    <SafeAreaView style={styles.container}>
      <View style={styles.header}>
        <Text style={styles.title}>智能家居</Text>
        <View style={styles.sensorCard}>
          <Text>温度: {sensors.temp}°C</Text>
          <Text>湿度: {sensors.humid}%</Text>
        </View>
      </View>
      <FlatList
        data={devices}
        renderItem={renderDevice}
        keyExtractor={item => item[0]}
      />
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  container: { flex: 1, backgroundColor: '#f5f5f5' },
  header: { padding: 20 },
  title: { fontSize: 24, fontWeight: 'bold' },
  sensorCard: { flexDirection: 'row', justifyContent: 'space-around', marginTop: 10, padding: 15, backgroundColor: '#fff', borderRadius: 10 },
  deviceItem: { flexDirection: 'row', justifyContent: 'space-between', alignItems: 'center', padding: 20, backgroundColor: '#fff', marginTop: 10, marginHorizontal: 20, borderRadius: 10 }
});

4. 数据库模型

// models/SensorData.js
const mongoose = require('mongoose');

const sensorSchema = new mongoose.Schema({
  timestamp: { type: Date, default: Date.now },
  temperature: Number,
  humidity: Number,
  light: Number,
  device_id: String
});

sensorSchema.index({ timestamp: -1 });

module.exports = mongoose.model('SensorData', sensorSchema);

// 使用示例
async function saveSensorData(data) {
  const sensorData = new SensorData({
    temperature: data.temp,
    humidity: data.humid,
    device_id: data.device_id || 'main'
  });
  await sensorData.save();
}

项目成果

• 已部署3个ESP32节点
• 响应延迟 < 500ms
• 稳定运行3个月
• 支持6路设备控制

总结

智能家居控制系统展示了物联网技术的完整应用，从硬件到云端再到移动端，构建了一套完整的智能化解决方案。