Building an IoT Prototyping Platform – Part III

This is part of a larger series, you might want to consider reading part one and two first.


As promised, I will now discuss the parts of the platform in more detail – starting with the server.

The main job of the server is to connect the prototype’s HTML and the ESP devices via MQTT and WebSockets. In a first iteration I used Node.js​ and Express to write it, resulting in about 600 lines of code. But since I am a UX designer and not a developer it’s probably best when I don’t write (a lot of) code.
The source code felt a bit crude and overly complex to me. It was hard for someone with little coding experience to get how the server worked. And that made maintaining and changing it hard for regular folks.

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Building an IoT Prototyping Platform – Part II

Here is the link to part one of this series, you might want to start there.

Based on the before stated principles and requirements for the prototyping platform I came up with the following architecture:

On the left you see the web server where the HTML of the Prototyping tool will be stored. On the right, the different hardware components (sensors and actuators, e.g. buttons, rotary encoders, LEDs) are connected to ESP8266 microcontrollers. In broad terms, ESPs are similar to Arduinos but also offer WiFi connectivity for a low price. In between sits a server to broker and translate the information coming from both sides.

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Building an IoT/Hardware Prototyping Platform

This is the first article of a series (parts: two and three), as this topic needs some more space and time. I have about half of the content written, so I will post updates as I go along.

Even though the Internet of Things (IoT) is a hot topic, with todays tools it is really hard to prototype and test IoT products or services beforehand. Very few tools allow us to use hardware components (like buttons or knobs) together with software user interfaces (UIs). Most software prototyping tools are closed systems offering no or only very little outside connectivity. Most of them only allow us to link screens together and that’s about it.

Plus, hardware prototyping is more complex than software prototyping: In addition to software interfaces, you need to know something about hardware, of course. Programming skills are needed if you want to tinker with them. And some knowledge about IoT protocols and platforms are helpful, too. These are skills very few user experience (UX) designers possess, since a lot of them focus on the design of digital-only products and services. Just google the evergreen argument whether UX designers should be able to code.


I thought that this was unfortunate, since prototyping is such a crucial activity for creating successful products or services. We need to make your ideas tangible, test them with users and evaluate their feasibility before starting to build the real thing. And since I have some experience with software prototyping tools and tinkering with hardware I started looking for a way to create IoT prototypes.

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A timeless time machine

In the picture below you see my first love computer: the Schneider CPC 464. It had a build-in tape deck and was sold with either a green or a color monitor. It was never as popular as its rival, the C64, but that did’t matter to me. I got the brownish monolith in ’85 as a Christmas present and 35 years later it still looks timeless, I think.

Sure, the screen is a bit small (size and resolution wise) for todays standard, 64k RAM is not too great, and music tapes are not a popular storage medium anymore – but it can still play the game heroes of my childhood: Elite, Gauntlet, and Saboteur.
That’s why I decided a while ago to re-buy my first computer, since I sold mine in my late teens to get money for a newer one.

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Notes to my (forgetful) future self

A few of my hobbies require quite a bit of research – hobbies like hardware tinkering, programming, installing stuff on a Raspberry Pi, building a 3d printer, coffee roasting, cooking… And since there are so many topics but only limited space in my head for quirky stuff, I started the habit of taking extensive notes. They became quite a life saver, since I often have to put things aside for a while – for example when “regular” life happens. Strange, I know.

If you care about note taking, take note (pun intended) and consider reading on. 

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DIY Raspberry Pi Laptop

In 2012 Motorola had a brillant idea on how to change the mobile computer landscape. They introduced the LapDock to the world (yes, I guess the pun was intended) – a laptop?like computer dock for your mobile phone. The German marketing slogan for it was: die Zukunft mobiler Computer Technik! (the future of mobiler computer technology).

This also describes the problem of the lapdock, it was too much future for 2012. Remember the Android phones of 2012? Using this thing must have been horrible. It also had steep price point (around $450). Thus it never really revolutionized the phone market.

But today the lapdock can be put to good use. You can turn it into a raspberry pi laptop with a few cables. You can get one for around 60 Euros on eBay every now and then. If you asked me why (a friend did), the short answer is: because we can!

You can find the writeup of the project over at and build one to climb up a step on the Raspberry Pi nerd ladder.

Rereading the Classics

For design to become corporate competency, it has to be more than just a department of people with the cool shoes, more than the activity you perform just prior to commercialization. Design is a way of approaching problem solving, decision making, and strategic planning that can yield better outcomes. It’s an open approach, and anyone in the organization can participate […].

Subject to Change, 2008



Peter Merholz wrote that in 2008 – more than a decade ago. And organizations are still trying to get a grip on this.


No longer AFK

Hey, long time no hear. I hope you are still around and haven’t given up on me. The last two months were quite busy, so I didn’t find the time to write. Sorry for that.

But I have a long list of things I want to tell you. This post will be a short update on the things that have kept my attention.

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So what you gonna do when the DS-GVO comes for you?

Bis letzte Woche war ich noch entspannt uninformiert was die oben genannte Abkürzung angeht. Hätte ich raten sollen, was das sein soll, hätte ich gesagt: „Vielleicht ein Sprayer-Pseudonym oder ein neues Hipster-Label, das versucht ohne Konsonanten auszukommen.“ Leider beides falsch.

Wie ihr wahrscheinlich schon lange wisst, handelt es sich um die neue Datenschutzgrundverordnung, die am 25. Mai 2018 in Kraft tritt. Mit ihr gibt uns die EU neue Rechte zum Datenschutz im Internet und gleichzeitig bekommen Personen und Firmen, die Dinge im Internet machen, neue Pflichten. (Welche genau, lest ihr besser bei Menschen nach, die sich damit auskennen, z.B. [1], [2], [3], [4].) Das europäische Internet hat quasi einen umfassenden Datenschutz-Frühjahrsputz verordnet bekommen.

Für mich bedeutet das, das mein Blog komplett überarbeitet werden muss. Inhalte, Plugins und das verwendete Layout wollen angepasst und zum Teil ausgetauscht werden. Zum Glück ist mein Blog recht schmal (wenig Inhalt!) und reduziert (ich nutzte bisher fünf Plugins). So musste ich vergleichsweise wenig anpassen. Super! Aber Spaß geht anders…

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