Node-Red and MQTT is awesome for real-time data, but what if you want to store and retrieve messages? Its rather straight forward to use Microsoft SQL Server as your database. MSSQL is free and easy to get started with.
I wanted to install a SSD on the Windows 10 desktop that my Node-Red ran on and ended up reinstalling windows. I had exported my flows and re imported them, all good. Later on I spent a few hours adding more good stuff. Everything was fine until a few days later when after a reboot, all my flows were gone!
Talk about a mix of anger, panic, and regret. Why didn’t I back up my work!?
Mars rover remixed and inspired by bolbots mars rover on Thinigverse. http://www.thingiverse.com/thing:1583399
The rover uses an Arduino 101 for brains, BLE for communication, and the Blynk app for remote control.
Kossel XL 2020 RepRap
I used my first RepRap Mendel Prusa 2 to print my Kossel Mini. The Kossel Mini has been a wonderful printer but I wanted something a tad bigger so I embarked on a journey to build a big Kossel RepRap 3D printer. As of writing this post there is a significant lack of affordable kits for large Kossel printers out there so I found some inspiration online and started building my own Kossel XL 3D printer. I am very proud of the results, its gorgeous and prints great!
If you don’t know already, RepRap printers are open source, no one owns them, you do! The community has a lot of information on building your own self replicating 3D printer, http://reprap.org/wiki/RepRap
Intel Arduino 101 based tank with BLE and Blynk!
This project uses the Intel Arduino 101 board that has a built in IMU and (BLE) Blue Tooth Low Energy. For the remote control I used the free Blynk app which is is available for Android and iPhone, it allows you to rapidly drag and drop some buttons to create a user interface. The Chassis is a Dagu DG012 from Sparkfun.
I tried to power the whole rig from the 5 AA battery pack that came with the chassis but the Arduino kept resetting on low voltage. Ideally I would use a nice LiPo battery pack but I think it’s reaching to expect a beginner to learn about the care and feeding of LiPos and purchase a charger so I chose to power the motors separately from the Arduino using a USB Battery pack. Be sure to remove the optional battery jumper on the Adafruit motor shield or you can fry some things, the power sources need to be separate.
The August 2016 DFW Hackster MQTT meeting was a blast. Here is a link to the online presentation. https://sway.com/DpyBV3JjNYoTFrsx
If you check back on this post I will update it with related videos. I promised some people at the event to do an Arduino MQTT demo and also finish up my video on the MQTT garage door opener.
If you want to get started with MQTT in your own time here are some resources:
What is MQTT
TI LaunchPad MQTT demo.
Software to Download:
Download HiveMQ it is free but they will make you fill out contact information for the download link. There is lots of great info and white papers on MQTT here so stay awhile and do some reading!
You will need a MQTT test client, I suggest MQTT.FX
Here are source code samples for NodeMCU, WeMos, and TILaunchpad.
Cortana can easily be extended to aid you with your DIY home automaton projects. In this example Cortana sends MQTT commands to open and close a garage door as well as ring the doorbell with custom jingles. By the way, you don’t have to use MQTT, you can also do a whole lot of other things as well from opening a file, opening a program, or launching your favorite websites.
As of the writing of this entry I am frantically trying to finish documenting the MQTT Doorbell and Garage Door Opener devices in separate posts. Hopefully I can get those whipped out in a few days.
Thermistors And Your Microcontroller
A thermistor is a simple temperature component, basically it is a variable resistor that the resistance changes in it depending on the temperature. Such a simple device needs a few more components and scaling in the microcontroller to give the desired C or F temperature reading.
A Programmable Logic Controller, PLC or Programmable Controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or light fixtures. PLCs are used in many industries and machines. http://en.wikipedia.org/wiki/Programmable_logic_controller
A HMI (Human Machine Interface) is the system by which people can interact with a machine. The user interface includes hardware (physical) and software (logical) components.