Untrickable laser alarm, with an easy-to-knock-out fusebox.
A tribute to (the alarms in) Mark of the Ninja.
In the game you have to sneak into buildings with high tech alarms. Some of the laser traps can be deactivated by knocking out the fuse box with a dart.
So I made a laser alarm with a fusebox that can be knocked out. This is mainly to keep kids occupied, and motivated to practice throwing.
A self-hosted, real-time, inexpensive open source car tracker built with Raspberry Pi Zero W, Nextcloud, and optionally Home Assistant.
I’ve had a few earlier tries at car position logging, read those first if you’re interested: Car logger 2.
Goal: logging and sharing location of my non-connected car, for practicality and fun.
Earlier tries was using a phone, but that had problems. No Android phone will switch back on if it runs out of power without manual intervention.
Volumio based internet radio, controlled by NFC, built in an old speaker.
Inspired by the extreemly good looking Spotify Box and QR based systems like Audiosphere, I wanted to make something similar for my kids. I’ve earlier built a few radios based on small, cheap bluetooth speakers like music angel, but wanted something with better sound this time.
QR are fast and cheap, so I made a quick prototype. It turned out they are unreliable when there’s no display to give feedback on how the camera sees them. Both lighting and focus was a problem.
See RadiOS part 1.
So I started making a prototype to figure out if I could “sense” both selections with GPIO pins, while the designer started modeling and rendering suggestions for the physical design. The solution chosen was to first set all volume control pins to high, and check which channel control points registered as on, then reverse (control points high, check volumes).
For sound we tore down a Music Angel portable speaker. It gave us two speakers, an amplifier running on 5V and a battery which we threw away. The built in soundcard gave horrible sound under certain conditions, so a cheap USB soundcard was used instead.
Read part one of Car-logger first, if you haven’t.
I chose to go with outdated Android phones in the previous article. Phones with CyanogenMod and no Google Play. This means that they run all free software, except for some firmware blobs and drivers. No background services driving up data or battery usage, no third party tracking my location.
I tried out Traccar. The app worked fine, but the backend was a big, horrible java thing. Poor UI, overkill for my purpose, and too much for me to get hacking on.