Articles

A collection of learnings, inspiration, thoughts and other developments.


Responsive background images with srcset and sizes

A while ago I searched around for a quick and easy solution to provide responsive background images. Somewhere I stumbled upon a fiddle demonstrating an amazingly neat trick. I tried this approach in a few projects and started some cross browser testing. It worked like a charm and I’d like to share and explain this idea.

Greentech 2019 Recap

Today I visited the greentech horticulture fair at the RAI Amsterdam. A huge trade show with an enormous amount of suppliers for horticulture. I visited this fair to get more knowledge about the latest technological development in the horticulture scene, and more specifically in the field of vertical farming, data management and automated farming. This is also interesting for the open insect farm project that I am working on.

Make101 – v0.1.0 Released

This is the release of the initial version of make101. A progressive web app that makes it possible to create

DIY Secure Access Card – Iteration 1

In the last couple of years, a lot of ideas and projects came by that required some sort of secure access based on a hardware component. For example, it would be nice to have proper access control for a makerspace of a locker inside a makerspace. Or, it would be nice to create a secure payment terminal for De Haagse Munt. And, in the light of making and DIY, it would be nice if this system would be based on open source hardware and software.

DIY Home Automation – Iteration 3

The goal of this series is to document the developments in DIY Home automation. This post describes iteration 3, focussing on optimizing the first smart thing: A sourdough proofing box. Read iteration 2 here, which was about setting up the mqtt server and the first smart thing connection.

DIY Home Automation – Iteration 2

I have used MQTT in projects before. MQTT is a great way to connect multiple devices to a central server and create a two way permanent connection. This is useful in all kinds of application, and especially in sensor networks. The goal of this iteration is to setup the mqtt-server on the raspberry (where also Home Assistant is running) and to monitor the room temperature using an esp8266 microcontroller, connected over wifi.

DIY Home Automation – Iteration 1

During the Odyssey Hackathon in Groningen 2 weeks ago I spoke to a lot of awesome people. One of them was a great guy from Ukrain, who showed me his home automation setup using My Sensors and Home Assistant. He was able to control and monitor everything in his home. It looked very nice, and the best part was that it was all open source and he was in full control.

De Haagse Munt development – Iteration 1

I have been working on a community currency in the city in work and live in: De Haagse Munt. A complementary currency to stimulate collaboration, sharing and inclusion in our society. One of the ideas for implementation is to create a DIY payment terminal, so that for instance merchants can accept local currency. In theory, they could do so by using the Haagse Munt App, but it seems that a payment terminal can create more acceptance amongst the people who should use this system.

Building a single channel LoRa gateway for The Things Network

I created a single channel LoRa gateway and node to connect to The Things Network using a Heltec Wifi LoRa v2 (ESP32-SX1276). This post is to help others, but also to save the developments so I can use them later myself. This post was originally posted at Hackster: https://www.hackster.io/Arn/single-channel-ttn-lora-gateway-and-nodes-with-esp32-sx1276-709612

Jekyll Reading time without plugins

Estimated reading time of a post is a feature that became popular, I believe, with Medium.

Nice write up! Would like to read about MAM developments.

Nice write up! Would like to read about MAM developments.

Adventures in IOTA land: The development of a Decentralised Urbanfarming Service

The travel in the IOTA landscapeFor a while now I have been following the developments in decentralised blockchain land. But to be honest, this has never lead to actions. I do not even own any Bitcoins myself.