Thingy:91 cellular vibration sensor

Thingy:91 cellular vibration sensor
A year ago I published an article about a very simple Vibration Logger using an Arduino Uno, an SD card and an accelerometer. Recently, the need to measure vibration came up again, but this time I wanted something better. A device that will let me monitor the readings from anywhere without the need to go ...

Arduino Vibration Logger 1

Arduino Vibration Logger
Recently I have had to monitor the operation of a system of pumps over a period of a few days. Monitoring in person would be a waste of time and would be a pain to do at night. The operation state of the pumps can be determined by the vibration of the system. When the ...

Real-time location tracking of individuals or things that are important to you

Real-time location tracking of individuals or things that are important to you
When I was taking my young kids to the park or playground I wished I had a solution that would tell me where they are in case they go out of sight. This led me to a project where I made a system to tell me in which direction (AKA bearing) and how far a ...

Integrating 433Mhz smoke detectors with Home Assistant 13

Integrating 433Mhz smoke detectors with Home Assistant
Smoke detectors are simple and effective means for saving lives and reducing damage to property in case of a fire. You should use smoke detectors in your house even if your local regulations don’t require you to do so. All smoke detectors make a loud beeping alarm sound if smoke is detected, but some models ...

Convention for compile time configuration of PlatformIO projects

Convention for compile time configuration of PlatformIO projects
Separation between code and data (specifically configuration data) is a critical concept in any development environment. Having worked a lot with the nodejs stack I found the way configuration is handled in embedded Arduino/PlatformIO projects surprisingly messy. I decided to come up with a convention to simplify this and I will describe it below. tl;dr, ...

Making a proper adapter board for the “smart” WiFi Rinnai 2

Making a proper adapter board for the
This is a quick follow-up post to my previous article about converting a Rinnai heater device to a smart device and controlling it with WiFi. Previously, when making the board that connects between the ESP32 and the traces of the Rinnai control panel, I did something that is not per-spec. I was using the ESP32 ...

Changing a “dumb” Rinnai water heater to a smart one 31

Changing a
This article covers a home automation project, in which I extended a control panel of a Rinnai gas water heater with an ESP32. The ESP32 then functions as an interface between the control panel and Home Assistant, a home automation software. tl;dr, the ESP32 sits as a MitM (proxy) on a few data lines inside ...

Repurposing unused steering wheel buttons as generic macros for an Android head unit 14

Repurposing unused steering wheel buttons as generic macros for an Android head unit
This article covers an automotive project, in which I connect unused buttons on my car’s steering wheel to a micro-controller, which in turn emulates a keyboard and mouse device to the car’s infotainment system via USB. tl;dr, the buttons form a resistor ladder and I use an STM32 black pill board to read the state ...

Should you throw away your CC41 HM-10 clones now that Android 8 is here? 42

Should you throw away your CC41 HM-10 clones now that Android 8 is here?
With the release of Android 8.0 (“Oreo”), I as well as others have noticed that they cannot find some HM-10 clone BLE modules when scanning for them with an Android 8.0 phone. Why is that happening and what can you do about it? tl;dr, the issue is due to a bug in the firmware of ...

40 cent DIY pressure sensor based on a capacitive principle 25

40 cent DIY pressure sensor based on a capacitive principle
Lately I am spending a lot of time working on Fochica. Fochica is a system that alerts parents if they unknowingly leave a child in a car. The Fochica device is Arduino-based, installed in a vehicle and communicates with the parents’ smartphones via Bluetooth. Fochica is a finalist in the Hackaday Prize 2017 competition and ...