本页目录

• Introduction
• 必备条件
• List of hardware and pinouts
• Wiring schemes
• ThingsBoard configuration
  • Provision your device
  • Provision your dashboard
• Programming the Raspberry Pi
  • MQTT library installation
  • Adafruit DHT library installation
  • Application source code
  • Running the application
• Data visualization
• See also
• Your feedback
• Next steps

Introduction

ThingsBoard is an open-source server-side platform that allows you to monitor and control IoT devices. It is free for both personal and commercial usage and you can deploy it anywhere. If this is your first experience with the platform we recommend to review what-is-thingsboard page and getting-started guide.

This sample application performs collection of temperature and humidity values produced by DHT22 sensor and further visualization on the real-time web dashboard. Collected data is pushed via MQTT to ThingsBoard server for storage and visualization. The purpose of this application is to demonstrate ThingsBoard data collection API and visualization capabilities.

The DHT22 sensor is connected to Raspberry Pi. Raspberry Pi offers a complete and self-contained Wi-Fi networking solution. Raspberry Pi push data to ThingsBoard server via MQTT protocol by using paho mqtt python library. Data is visualized using built-in customizable dashboard. The application that is running on Raspberry Pi is written in Python which is quite simple and easy to understand.

The video below demonstrates the final result of this tutorial.

Once you complete this sample/tutorial, you will see your sensor data on the following dashboard.

必备条件

你需要启动并运行ThingsBoard服务， 建议使用演示服务。

另一种选项是通过安装指南进行独立部署 Windows用户应遵循本指南，已经安装docker的Linux用户执行以下命令:

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mkdir -p ~/.mytb-data && sudo chown -R 799:799 ~/.mytb-data
mkdir -p ~/.mytb-logs && sudo chown -R 799:799 ~/.mytb-logs
docker run -it -p 9090:9090 -p 7070:7070 -p 1883:1883 -p 5683-5688:5683-5688/udp -v ~/.mytb-data:/data \
-v ~/.mytb-logs:/var/log/thingsboard --name mytb --restart always thingsboard/tb-postgres

以上命令可以完成ThingsBoard安装和生成演示数据。

你可以通过ThingsBoard页面地址http://localhost:8080、 用户名tenant@thingsboard.org和密码tenant进行访问， 有关模拟帐户请参见此处。

List of hardware and pinouts

• Raspberry Pi 3

• DHT22 sensor

• Resistor (between 4.7K and 10K)

• Breadboard

• 2 female-to-female jumper wires

• 10 female-to-male jumper wires

• 3 male-to-male jumper wire

Wiring schemes

Finally, place a resistor (between 4.7K and 10K) between pin number 1 and 2 of the DHT sensor.

The following picture summarizes the connections for this project:

ThingsBoard configuration

Note ThingsBoard configuration steps are necessary only in case of local ThingsBoard installation. If you are using Live Demo instance all entities are pre-configured for your demo account. However, we recommend reviewing this steps because you will still need to get device access token to send requests to ThingsBoard.

Provision your device

This step contains instructions that are necessary to connect your device to ThingsBoard.

Open ThingsBoard Web UI (http://localhost:8080) in browser and login as tenant administrator

• login: tenant@thingsboard.org
• password: tenant

Goto “Devices” section. Click “+” button and create a device with the name “DHT22 Demo Device”.

Once device created, open its details and click “Manage credentials”. Copy auto-generated access token from the “Access token” field. Please save this device token. It will be referred to later as $ACCESS_TOKEN.

Click “Copy Device ID” in device details to copy your device id to the clipboard. Paste your device id to some place, this value will be used in further steps.

Provision your dashboard

Download the dashboard file using this link. Use import/export instructions to import the dashboard to your ThingsBoard instance.

Programming the Raspberry Pi

MQTT library installation

The following command will install MQTT Python library:

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sudo pip install paho-mqtt

Adafruit DHT library installation

Install python-dev package:

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sudo apt-get install python-dev

Downloading and install the Adafruit DHT library:

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git clone https://github.com/adafruit/Adafruit_Python_DHT.git
cd Adafruit_Python_DHT
sudo python setup.py install

Application source code

Our application consists of a single python script that is well documented. You will need to modify THINGSBOARD_HOST constant to match your ThingsBoard server installation IP address or hostname. Use “demo.thingsboard.io” if you are using live demo server.

The value of ACCESS_TOKEN constant corresponds to sample DHT22 demo device. If you are using live demo server - get the access token for pre-provisioned “DHT22 Demo Device”.

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import os
import time
import sys
import Adafruit_DHT as dht
import paho.mqtt.client as mqtt
import json

THINGSBOARD_HOST = 'demo.thingsboard.io'
ACCESS_TOKEN = 'DHT22_DEMO_TOKEN'

# Data capture and upload interval in seconds. Less interval will eventually hang the DHT22.
INTERVAL=2

sensor_data = {'temperature': 0, 'humidity': 0}

next_reading = time.time() 

client = mqtt.Client()

# Set access token
client.username_pw_set(ACCESS_TOKEN)

# Connect to ThingsBoard using default MQTT port and 60 seconds keepalive interval
client.connect(THINGSBOARD_HOST, 1883, 60)

client.loop_start()

try:
    while True:
        humidity,temperature = dht.read_retry(dht.DHT22, 4)
        humidity = round(humidity, 2)
        temperature = round(temperature, 2)
        print(u"Temperature: {:g}\u00b0C, Humidity: {:g}%".format(temperature, humidity))
        sensor_data['temperature'] = temperature
        sensor_data['humidity'] = humidity

        # Sending humidity and temperature data to ThingsBoard
        client.publish('v1/devices/me/telemetry', json.dumps(sensor_data), 1)

        next_reading += INTERVAL
        sleep_time = next_reading-time.time()
        if sleep_time > 0:
            time.sleep(sleep_time)
except KeyboardInterrupt:
    pass

client.loop_stop()
client.disconnect()

Running the application

This simple command will launch the application:

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python mqtt-dht22.py

Data visualization

Finally, open ThingsBoard Web UI. You can access this dashboard by logging in as a tenant administrator.

In case of local installation:

• login: tenant@thingsboard.org
• password: tenant

In case of live-demo server:

• login: your live-demo username (email)
• password: your live-demo password

See live-demo page for more details how to get your account.

Go to “Devices” section and locate “DHT22 Demo Device”, open device details and switch to “Latest telemetry” tab. If all is configured correctly you should be able to see latest values of “temperature” and “humidity” in the table.

After, open “Dashboards” section then locate and open “DHT22: Temperature & Humidity Demo Dashboard”. As a result you will see two digital gauges and two time-series charts displaying temperature and humidity level (similar to dashboard image in the introduction).

See also

Browse other samples or explore guides related to main ThingsBoard features:

• Device attributes - how to use device attributes.
• Telemetry data collection - how to collect telemetry data.
• Using RPC capabilities - how to send commands to/from devices.
• Rule Engine - how to use rule engine to analyze data from devices.
• Data Visualization - how to visualize collected data.

Your feedback

Don’t hesitate to star ThingsBoard on github to help us spread the word. If you have any questions about this sample - post it on the issues.

Next steps

• 入门指南 - 快速学习ThingsBoard相关功能。

• 安装指南 - 学习如何在各种操作系统上安装ThingsBoard。

• 连接设备 - 学习如何根据你的连接方式或解决方案连接设备。

• 可 视 化 - 学习如何配置复杂的ThingsBoard仪表板说明。

• 数据处理 - 学习如何使用ThingsBoard规则引擎。

• 数据分析 - 学习如何使用规则引擎执行基本的分析任务。

• 高级功能 - 学习高级ThingsBoard功能。

• 开发指南 - 学习ThingsBoard中的贡献和开发。