The idea


I've been dragging my feet to enter this contest.  Working with light is not my forte.

But The Internet of Holiday Lights RoadTest Plus has a creative component. And  that's what pulled me in.

I was going to build an Electro Mechanical Xmas Wreath of Things!





This is the proposal I submitted:


Christmas Wreath of Things

...  my entry is an electro-mechanical wreath.


The wreath is a combination of mechanics, electronics and internet connectivity.

For each advent week, there will be a light. above the light is a filter that hides all four lights initialy, and will reveal a light each Sunday, 'candle wreath style'.



Microcontrollers are used to motor-drive the optical filter. The internet will be used 'IoT compliant', to check what date it is, and reveal the correct number of lights based on that.

The wreath will work every year without user input. Plug it in and it will adjust itself to the right state of advent.

My aim is to give this either a K'Nex or steampunk look and feel.



In fact I don't know anything about te design yet. It's just an idea at this moment.

You'll find out together with me how it materializes.


At that time, I really didn't know much. As it turned out, the only thing I've left from the original idea was the dumb lights and motorized filter.

All other things changed during the build.

In this post I will not go into technical details. There's a list with all blog posts about this gizmo at the end of this post.


What did I come up with?




I like to challenge the nature of the exercise.


The focus was on lights. I came up with the idea to make the lights an intrinsic part of the design - but a downplayed part.

It would have been obvious to switch on one light for each Sunday in the advent.

I inverted that thought process: what if the lights are static, but something else makes them go on and off.

The mechanically driven optical filter does that  job.


The Infineon RGB shield can handle high power leds easily. So I used it to drive standard low power leds.
It's perfectly capable of doing that, but you're playing at the very low edge of its range. It's a tricky balance because you can easier overdrive standard leds than the sturdy high power ones.

The shield did an excellent job. Even though I did not put advent intelligence in the lights, I did animate them.

peteroakes's (I bet he'll be mentioned by some other participants too ) Infineon library was instrumental for a painless exercise.






The Eclipse IoT. What's the use of the internet of things if you only talk to yourself?

fvan and I have our gizmos connected to each other.

Our devices act differently when we're both on-line. How novel is that?



Frederick's gizmoJan's gizmo


We think we've used the internet as it's supposed to be used. To interact with others.

And we've used it as 'things'. There's no human interaction. Both things are happy when the counterpart is live, and they show it!




The Arduinos. The Yún drives the whole thing. It's filled up with more than 90%. It has a very down-to-earth duty.

The UNO is doing a more creative job. I've given it as a present to one of my kids that helped me build the wreath.

Maybe one day she ...

What changed during the build?


I started with virtually no ideas. And even then almost everything changed.


  • I was going to use the internet to get the current date. I'm a novice to IoT - this is my first experience - and thought that it was all about using on-line services and functionality.

When I was setting up the Yún, I found out it has linux running - and has time sync functionality.

So I changed my mind, stepped away from searching for an on-line time service, and used that linux part to get at the right date - with localization support.


  • That also meant that I had to come up with something else for the IoT part. The work with Frederick more than filled that gap. It was a blast working together - you get the warm fuzzy when the gizmo lights up when you're not paying attention.


  • The mechanical part went through several changes.

I started with a light dc motor, but that was a bit hard to control. I didn't have many options to provide position feedback - let alone brake the fast but weak motor. Ditched it.

Idea two was a servo motor that I have lying around. It does the job better, but it was looking dull. I wanted gears and shiny copper.

In came the final solution: a stepper motor from a defunct flatbed scanner.



I struggled somewhat with driving the motor - and wrote about that in the blogs listed at the bottom of the blog. It turned out to be a perfect solution.

As an added bonus, the stepper does not run very smooth. That adds to the look and feel of my design.

From the start, I wanted it to look scabby. I'm quite pleased with how it behaves:



  • I was going to build it alone. One of my kids came to the rescue when I was about to cut off my fingers during the arts&crafts part.

That may have been the part that I enjoyed most.




Wrap up:


'twas fun! I'm glad I participated - and I learned a few new things along the way.

My design is not going to be the brightest light around here (total current used for leds: < 150 ma, all Arduino Yún  leds included ).

But it moves. And it communicates. It's alive!

All the best for 2015 !



My Blog Posts:


The posts in this table tell the whole story from beginning till completion. They are listed - and  written - in sequence, so you can follow along with me.



My entry for the Internet of Holiday Lights is an electro-mechanical wreath.

My first blog post was a brain dump of possibilities.

In my second post I made a paper prototype.

My third post was about getting the Arduino Yun up and running.

In the fourth post I used the Linux part of the Yun to get at the current date and time.

In the fifth post I scavenged a stepper motor from a flatbed scanner.

In post six that motor was running.

Post seven is covering the Infineon RGB LED shield.

My post number eight is an aside on programming the advent calendar logic.

In post nine I'm covering the creative 'Arts & Crafts" part.

Post number 10 covers Time and Event handling,

and post 11 reveals the IoT conspiracy that Frederick and I prepped.

Post-Christmas design: [Christmas Wreath of Things] Internet of Holiday Lights : post Christmas blues

And the bonus kicker: [Christmas Wreath of Things] Internet of Holiday Lights - Bonus kicker: the IoT talks (a spoken tribute to Science Fair kits)

Comparing the Infineon arduino libraries from our element14 team.

The Official Road Test Review©.

Bonus material


Frederick's post on our shared design: [Christmas Tree] Internet of Holiday Lights - Special Feature

You can join in. Topics are shared on this thread: Internet of Holiday Lights:  Join the secret IoT Service - open for all


After January 6, I switched over to a post-Christmas design: [Christmas Wreath of Things] Internet of Holiday Lights : post Christmas blues

Photo 08-01-15 12 12 32.jpg


Bonus Bonus:

The Internet of Things shouts out the names of my fellow road testers:





A playlist of 11 videos I've uploaded during the work. Some made it to the blog posts.



and some photos:


backside.jpg dark.jpg frederick ster.jpg IMG_3424.JPG


IMG_3503.JPG IMG_3984.JPG IMG_3986.JPG


IMG_3987.JPG IMG_3990.JPG


IMG_4006.JPG Photo 23-12-14 23 28 16.jpg wreath0001.jpg