ESP8266 – Internet of Things

Learn How to Build a Condition Monitoring IoT System

Hans Scharler — Thu, 22 Feb 2018 16:00:49 +0000

Douglas Mawrey created a Smart Humidity Sensor using ThingSpeak to collect data, MATLAB to analyze the data, and IFTTT to send push notifications for certain conditions. This project uses the outdoor temperature to determine the ideal indoor humidity and inform you about the room’s comfort. The data and condition results are displayed on Douglas’ public ThingSpeak channel 418058. This project is a good starting point to see the power of the MATLAB integration on ThingSpeak and how to perform real-time condition monitoring.

Setting up the Sensor

This project uses the ESP-based NodeMCU as an IoT gateway to forward sensor data to ThingSpeak. The NodeMCU is essentially a microcontroller and a Wi-Fi device that costs less than $10 US. The humidity sensor that is used in this project is the DHT11. This a very common sensor used to monitor temperature and humidity. The sensor either comes in a 4 pin or 3 pin package. The NodeMCU is programmed with the Arduino IDE using the code in Douglas’ tutorial or GitHub.

Using ThingSpeak Metadata

Douglas uses the metadata setting within a ThingSpeak channel to store condition ranges. This allows you to adjust settings in your online analytics code without redeploying new code. Each ThingSpeak channel has a metadata setting. You can store arbitrary text data that can be used in your MATLAB Analysis code. To load your channel’s metadata into MATLAB, use the webread function and add metadata=true to the ThingSpeak API Read Data request.

indoorChannelData = webread(strcat('https://api.thingspeak.com/channels/', ...
                                    num2str(indoorChannelID), ...
                                    '/feeds.json?metadata=true&api_key=', ...
                                    indoorChannelReadKey));

Using MATLAB for Condition Monitoring

Douglas uses MATLAB on ThingSpeak to determine the proper condition. This is a common requirement in complex IoT systems. This example could be a good starting point for building a condition monitoring system for industrial maintenance applications. You use MATLAB to determine the target humidity using a polynomial fit over the lookup data.

lookupFit = polyfit(humidityLookup(:, 1), humidityLookup(:, 2), length(humidityLookup) - 1);
optimalHumidity = polyval(lookupFit, curTempOut);

humidityDiff = curHumidity - optimalHumidity;

Using IFTTT for Alerts

Often you want to get notifications when a certain condition is met. Douglas shows you how to use IFTTT to send push notification directly to your phone. In this project, MATLAB is determining the condition and then interfaces with the IFTTT API to send the push notification. To send push notifications via IFTTT, use the webwrite function in MATLAB.

webwrite(strcat('https://maker.ifttt.com/trigger/', makerEvent, ...
                '/with/key/', makerKey), ...
                'value1', stateMsg, ...
                'value2', char(timeSinceChange, 'hh:mm'));

All of the MATLAB code can be deployed on ThingSpeak and scheduled to be executed periodically without having this on your desktop computer. The complete Smart Humidity Sensor project tutorial is available on Hackster.io. Feel free to discuss on the MATLAB Maker Community.

Collecting Resting Heart Rate Data Using ThingSpeak With a $5 Wi-Fi Device

Hans Scharler — Fri, 27 Oct 2017 18:36:47 +0000

Naman Chauhan from SRM University created a proof-of-concept project that measures your resting heart rate and sends the data for analysis via a $5 Wi-Fi device. The project is fully documented with the source code on either Hackaday or Hackster.

Naman uses an Arduino for processing the heartbeat data and turns the data into heartbeats per minute. Then, periodically, the device sends the data to ThingSpeak for data storage and data analysis using MATLAB. The heart rate monitor is connected to the internet using DFROBOT’s ESP8266 Wi-Fi Bee. The Wi-Fi Bee turns serial data-to-Wi-Fi.

This heart rate monitor sensor is a pulse sensor which is developed based on PPG techniques. This is a simple and low-cost optical technique that can be used to detect blood volume changing in the microvascular bed of tissues. It is relatively easy to detect the pulsatile component of the cardiac cycle according to this theory.

To build your own, check out Naman’s tutorial on either Hackaday or Hackster.

Send Bulk Sensor Data to ThingSpeak for Analysis

Hans Scharler — Thu, 20 Jul 2017 15:00:17 +0000

Many IoT projects collect data from a sensor and send the data to ThingSpeak at the same time over and over. To continuously collect and send data to the cloud requires the device to be powered and connected all of the time. A battery-powered IoT device like a Particle Photon or Onion Omega2 would run out of power quickly. There are many IoT applications where you want your IoT device to collect the data offline over a long period of time, then send the data all at once to ThingSpeak for analysis.

The ThingSpeak team at MathWorks is excited to announce Bulk-Update! This new ThingSpeak feature is targeted at IoT devices trying to optimize battery use by allowing the device to update a lot of data at once. To help you get started with bulk-update, we have written examples for Arduino, ESP8266, Particle Photon, and the Raspberry Pi 3.

Once your data is on ThingSpeak, it is easy to analyze using the MATLAB Analysis and Visualization apps within ThingSpeak, MATLAB Online, or Desktop MATLAB. To read data from ThingSpeak into MATLAB, use the ThingSpeak Support Toolbox and the thingSpeakRead command. We have released documentation and examples to help you get started with bulk-update on ThingSpeak.

Resources for Bulk-Update

[Kickstarter] nodeIT – Small, Stackable IoT Device

Hans Scharler — Tue, 18 Aug 2015 12:56:57 +0000

Kickstarter projects pop up all of the time. Developers are looking to raise money for their projects so they can order a larger production run and gauge market reaction. A lot of recent projects are trying to address the “Maker Community” by making it easier to prototype connected devices and sensors. We just found one called, “nodeIT” from Sweden.

The nodeIT is centered around the ESP8266 Wi-Fi microcontroller and allows you stack other boards to extend its base functionality. Once the nodeIT is connected to your Wi-Fi network, you can easily publish data to ThingSpeak and visualize the results, such as data collected by a barometric sensor.

For more information about nodeIT, follow their Kickstarter campaign and check out their ThingSpeak Room Monitor project.

[via Kickstarter]

Collecting Dust Levels with ThingSpeak and ESP8266 Wi-Fi

Hans Scharler — Fri, 07 Aug 2015 16:32:50 +0000

Using the ESP8266 Wi-Fi module, [shadowandy] built a dust sensor to measure dust levels in his house. The project incorporates the Shinyei PPD42NS dust sensor to do the measurements and posts the data to his ThingSpeak channel from data collection and reaction to dust levels.

The sensor records the PM10 and PM2.5 dust levels to get an accurate indication of the dust in the air. This project is a great example of how a little sensor could turn into something important for protecting machine shops, construction sites, and garages.

[via shadowandy / GitHub]

Soldering Iron Connected to ThingSpeak with #NodeMCU and #ESP8266 Wi-Fi

Hans Scharler — Fri, 24 Jul 2015 18:40:20 +0000

[Vegard Paulsen] created a solder iron that reports its usage and temperature to ThingSpeak and alerts him when it was left on. He uses an NodeMCU / ESP8266 Wi-Fi module to collect the data and post it to his ThingSpeak channel. Once the data is on ThingSpeak, he is able to send push notifications to his phone using the ThingSpeak React App.

Hackaday.com wrote an article about Vegard’s soldering iron connected to the Internet of Things. Here’s what they had to say:

The data pushes out to the ThingSpeak server which handles pushing data out to the bigger network, and data representation (like the cool Google gauge…). The best part: [Vegard] gets a phone notification when he accidentally leaves his soldering iron on. How perfect is that?

That looks a lot like our desks… wires, microcontrollers, pliers, cutters, Wi-Fi modules, and soldering irons. And now, the soldering iron is on the Internet of Things.

[via Vegard Paulsen / Hackaday.com]

Basement Dehumidifier Tweets Its Humidity with ThingSpeak and ESP8266 Wi-Fi

Hans Scharler — Wed, 15 Jul 2015 17:17:25 +0000

ThingSpeak user, Spencer, adapted a humidifier that sits in his basement. He is solving a common issue about humid basements. If your dehumidifier fails, you get wet things you have stored and then mold. Spencer created a humidity board using the DHT22 that measures humidity and then reports the data to his ThingSpeak Channel via the ESP8266 Wi-Fi module. Once the data is stored in ThingSpeak, he uses ThingSpeak React to update Twitter when things get out of whack.

[via Twitter]

There is a Hamster on Twitter Now… Thanks to ThingSpeak, Arduino, and ESP8266 Wi-Fi

Hans Scharler — Mon, 20 Apr 2015 15:21:48 +0000

What does an adorable hamster need? Internet of Things, but of course. Using ThingSpeak, ESP8266 Wi-Fi, and Arduino, Ángel from San Sebastián built a monitoring system for his hamster which is dubbed “RunnerHam“.

RunnerHam Tweets his distance and time when he takes a run on his wheel, “I’m done! 57.62m at 0.61m/s”. You can also check out his ThingSpeak Channel where he records lots of data about his day.

Ángel also released an Instructables explaining his “pet project” so you can make your own and make your own enhancements. Just imagine what you can do with some sensors, connectivity, and ThingSpeak Web Services!

[via Instructables]

New ThingSpeak Forum Dedicated to the ESP8266 Wi-Fi Module

Hans Scharler — Fri, 06 Feb 2015 16:56:34 +0000

Over the past few months, we have seen the ESP8266 Wi-Fi Module take the DIY Internet of Things makers by storm. The main reason is the ESP8266 is less than $5US includes Wi-Fi connectivity and the ability to be programmed like a microcontroller. Another trend that we are seeing is that many of the ESP8266 modules are being connected to ThingSpeak web services. We are getting a lot questions every day, so we wanted to setup a new forum in our ThingSpeak Community dedicated to the ESP8266 Wi-Fi Module. Feel free to ask questions about ThingSpeak support with your ESP8266, we will do our best to provide answers and solutions on how to get the ESP8266 up and running quickly with ThingSpeak.

>> ThingSpeak ESP8266 Forum <<

[Instructables] Wi-Fi Temperature Data Logger

Hans Scharler — Fri, 03 Oct 2014 16:45:24 +0000

[noel portugal] is at it again! This time Noel created a simple Wi-Fi based sensor data logger using ThingSpeak, the ESP8266 Wi-Fi module, and a digital temperature sensor. At the heart of the project is a low-cost Wi-Fi module that could be the basis for many Internet of Things projects.

Everything you need to know in order to build your own sensor logging project is on Noel’s Instructables.

[via Instructables]