I confess. I have been sucked in to a home automation addiction. The next thing on my radar was to automate roller blinds. There are commercial products available but the ones I found are surprisingly expensive (about 80 - 90 USD). Since I need a bunch, it was hard to motivate the purchase (and less fun). I decided to design my own.

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These were my requirements:

WiFi capable
MQTT control (0% - 100%)
Manual push button operation
Use low cost standard electronic components and 3D-printable parts
Persist state on power off

This instructable is a followup to https://www.instructables.com/id/Motorize-IoT-With...

Step 1: Bill of Materials

NodeMCU 1.0 (aka V2) development board: http://www.gearbest.com/transmitters-receivers-mo...
Motor shield: http://www.gearbest.com/boards-shields/pp_340732....
Geared stepper motor 28BYJ-48: http://www.gearbest.com/other-accessories/pp_2311...
Micro switch: http://www.gearbest.com/development-boards/pp_156.... Please note that if you want to use the printed electronics box you need to get these exact switches or same dimension ones. The lid has a socket modeled after this particular switch.
M3x8 hex socket allen screws
MicroUSB-cable for power and programming and any USB phone charger
3D printer (or printing service)
M3 knurled brass inserts M3x5x4: http://www.ebay.com/itm/252468136038
IKEA roller shade Tupplur (or any roller shade with compatible inner radius): http://www.ikea.com/us/en/catalog/products/603091...
Some wires, soldering equipment and basic skills

The motor parts add up to about 15-20 USD per unit. The shade itself is 19 USD.

Step 2: Wiring

Wire the motor to the shield as seen in the pictures. Take note of the colors.
Solder cables to the micro switch as seen in the picture. If you can, use red, black and white as in the picture.
Attach the button wires to (GPIO) 5 as seen in the picture

Step 3: Set Up a MQTT Broker

MQTT is a lightweight publish/subscribe protocol suitable for small IoT devices. The devices interact with a message broker which manages the distribution of messages. You can either use a local mqtt broker, e. g. Mosquitto inside your own network or connect to a cloud MQTT broker. Which option is best? It depends on your needs. If you want to be able to connect to the broker from anywhere you may prefer the cloud option. If you prefer to keep your IoT within you network you should use a local broker.

Setting up a cloud broker:

Register at CludMQTT: https://www.cloudmqtt.com/
Creat a new broker instance
Click the instance info and keep the info handy
For testing purposes, download MQTT.fx: http://mqttfx.jfx4ee.org/
Add a profile to MQTT.fx with the credentials from your newly created cloud broker.
Connect. If it works you have successfully tested the connection to your fresh cloud broker.

Step 4: The Software

The ESP8266 on which the NodeMCU development board is a single chip computer with I/O capabilities and WiFi. The chip can be programmed in various ways. The two most popular options are the Arduino IDE and the Lua interpreter. For this project I chose Lua out of convenience. Some of the features in the software are easier in Lua because of the built in file system.

Flash the Lua Firmware

Even if your NodeMCU is pre-flashed with a Lua firmware I recommend that you re-flash it with a new firmware. That way you get a fresh version and can slim the binary to only contain the needed modules.

Cook a LUA firmware here: https://nodemcu-build.com/ Select the following modules: file, GPIO, MQTT, net, node, PWM, timer, WiFi and optionally enable SSL
Wait for the email with the firmware download link, then download. It should only take a few minutes. You may want to check your spam filter for it. That's where mine was.
Download Flash tool: https://github.com/marcelstoer/nodemcu-pyflasher/...
Flash the firmware using the flash tool
1. Run the tool
2. Connect the NodeMCU holding the flash button
3. Select the serial port
4. Select the firmware file
5. Press Flash

Install the rollerblind code

Download the roller blind code here: https://bitbucket.org/ehsmaes/motor_rollerblind/s...
Download ESPlorer IDE: https://esp8266.ru/esplorer/
Open Esplorer
Select the serial port
Connect
Open all the lua files
Edit settings.lua and enter WiFi and MQTT settings
Upload all lua files (Save to ESP)
Reset device

Step 5: Dry Run

Now would be a good time to check the software and wiring.

Open up esplorer and connect
Run the following command line (see picture). The motor should rotate 1000 steps (about a quarter of a turn.

Step 6: 3D Printed Parts

I designed the parts in Fusion 360.

Download the parts from http://www.thingiverse.com/thing:2065722 and start printing!

Step 7: Assembly

This is what you need to do for assembly (watch video):

Heat the soldering iron to about 200 degrees C (400 F).
Embed the nut inserts into the plastics by placing the insert over the tip (so it heats up) and gently push it into the plastic sockets (see picture).
Remove the lever from the micro switch
Loosen the plastic hinge on the lid button (gently push it out and back in)
Push the micro switch in place
Push the motor shield into place
Insert the motor
Screw the plastic parts

Important note on power: I have found that if you have a narrow window or short travel distance you are fine with just USB power (5v) but for wider and longer blinds you need external power (max 9v DC). You attach external power to the motor shield. Make sure you disconnect USB before you do or you are likely to fry something.

Step 8: Mount Rollerblind

Replace the springloaded end mount and insert of the Ikea rollerblind with the printed motor mount and printed insert.

Step 9: Calibration

Windows are of different heights; hence the gadget has to be calibrated. This is how:

Long press the button (> 2s)
The shade starts going down
When the shade reaches desired bottom position, short press
When the shade reaches derired top position, short press again
Done!

Step 10: MQTT Control

Download MQTT.fx from here: http://mqttfx.jfx4ee.org/index.php/download
Start MQTT.fx
Create a profile to match the broker you already set up
Connect
Subscribe to the topic from config.lua e. g. "/house/masterbedroom/#" wihtout the quotes. If you don't have anything else on your broker bus you can subscribe to everything (e. g. "#")
You should see heartbeat messages sent out from the device every two minutes
To control the device, publish to the topic matching config.lua "/house/masterbedroom/rollerblind/0/set"

Of course, this setup is obviously not terribly useful for daily operation but it will help you weed out any potential problems. If you just want to control mqtt devices you can download a MQTT cotrol dashboard on you phone. If you want to use other general home automation software I think you should find that most support MQTT integration.

Step 11: Integration With Openhab (optional)

I will give you an example of integration with the home automation solution I am using. If you have a pre-installed openhab home automation solution or would like to set one up (there are guides on their home page), this is what you should do to integrate the roller blind.

Install and configure the openhab according to their instructions
Install MQTT binding
Configure MQTT binding for your previously configured broker (local or cloud)
Add the roller blind to your items and sitemap file. See example below.

Item:

Dimmer masterbedr_blind1 "Rullgardin 1" <rollershutter> { mqtt=">[ohab:/house/masterbedroom/rollerblind/0/set:command:*:${command}],<[ohab:/house/masterbedroom/rollerblind/0/status:state:default]" }

Sitemap: