SpaceAPI LED Map

A map of hackerspaces lasercut from plywood, with their SpaceAPI opening states shown in red and green LEDs.

The LEDs are WS2812-compatible bulb-shaped LEDs, and they are controlled by an ESP32-C3 board.

This is a work in progress (2nd half 2024) project; documentation will be updated as the project progresses.

Contents of This Repository

erfamap-output/

The data for lasercutting the map was generated using a modified version of my Erfamap project, which uses the api.spaceapi.io SpaceAPI aggregator instead of the CCC internal Wiki to determine which dots to place where. A lot of this data was edited by hand in order to improve it for laser cutting.

• spaceapi-info.json is the cache file used by the modified script. It has been edited manually to remove some entries which had broken or unsuitable API endpoints.
• map.svg is the output file generated by the modified script.
• map-prepared.svg is the file that has been prepared for laser cutting and engraving:
  • Labels have been move manually so that they are easier to assign to the correct LED, and so they don't overlap with any of the country borders.
  • Text has been converted to paths.
  • All paths have been assigned to layers corresponding to how they should be processed.

The modified Erfamap script will be released at a later point after some further cleanup.

pcb/

The KiCad project for the PCBs that connect everything together.

Each PCB connects to 10 LEDs, and the PCB can be chained together to form a single WS2812 chain. There are 83 LEDs in the current version, so a total of 9 of these PCBs is required. The ESP32-C3 needs to be soldered to the first PCB.

⚠️ There is a small issue with V1.0 of the PCB! (Please check the version number on the silk screen!):

Pins 1 and 4 of the OUT pin header are swapped - this can be easily worked around by swapping wires number 1 and 4 in the JST connector plugged into this header.

esp32/

The PlatformIO Arduino project for the ESP32. It perfoms the following tasks:

• If no WiFi AP has been configured yet, it starts an AP on its own
  • Connect to the AP (SSID: spaceapimap, PSK: 12345678)
  • Configure the WiFi network the ESP32 should connect to
• Connect to the WiFi network defined previously
• Obtain the current time through NTP
• Fetch the aggregated SpaceAPI responses from api.spaceapi.io and parse the JSON response
• Update the WS2812 LEDs

The list of SpaceAPI endpoints to display is defined in esp32/src/spacemap.h. The position of an endpoint in the spaces array corresponds to the index of the WS2812 LED it controls.

led_plugging_tool/

A 3D-printable tool that helps with cutting the LED legs to size and attach them to JST ZH-4 connectors the correct way.

Usage:

1. Print the tool on a 3D printer.
2. Put a LED bulb-first into the tool hole. Especially on first use, make sure that it's all the way in.
   • The LED should only fit in one orientation.
3. Use a pair of wire cutters to cut the LED legs as close to the tool's surface as possible.
4. Take a cable fitted with JST ZH-4 connectors and push one connector firmly onto the LED legs inside the tool.
   • The connector, too, should only (fully) fit in one orientation.
   • You may need to bend the LED legs a little to get them to a pitch close enough to 1.5mm that the connector will slide on.
5. Pull the cable to remove the connector and LED from the tool.
6. Repeat steps 2-5 for every LED you need to prepare.

Components

• WS2812-compatible 5mm bulb LEDs: https://de.aliexpress.com/item/1005005003701575.html
• Black 5mm LED sockets: https://de.aliexpress.com/item/1005005062684329.html
• ESP32-C3 Super Mini: https://de.aliexpress.com/item/1005006252882434.html
• JST-ZH cables: https://de.aliexpress.com/item/1005007298855435.html (4P, Reversed)