2. Custom Parts

The Flight Computer requires the fabrication of some custom components: a printed circuit board (PCB) and several 3D printed parts.

2.1. Printed Circuit Boards

The PCB files can be found on GitHub in the pcb/standard folder for the standard-sized Flight Computer and pcb/mini folder for the mini. The most recent versions are at the top-level of these folders but older versions can be found in the archive folder.

The PCBs were designed using Fritzing, an easy to use (and free) electronic prototyping tool suitable for simple designs. Fritzing design files have the extension fzz. This design is then exported from Fritzing as a collection of gerber files, saved as a single zip archive.

There are several companies that can make the PCBs for you from the gerber files. We have had great success with OSH Park. If you want to order the most recent version of either board directly from them, you can do so (standard, mini). In July 2019 these were available for $109 (standard, set of 3) or $40 (mini, set of 3) before shipping and any applicable tax.

2.2. 3D Printed Parts

A fully assembled Flight Computer also requires some 3D printed parts: a battery holder, a breadboard clip (only for the standard Flight Computer), and an external interface to be mounted on the outside of the pod that holds a switch and indicator LEDs. These can be found in the same GitHub repository as the PCB files (GitHub) but under the 3d_print folder. The parts were designed in AutoDesk Inventor (ipt files) and exported for 3D printing as stl files.

We have printed these parts using an Ultimaker 2+ with ABS filament. The best results have been obtained with a 0.10 mm layer height, 30% fill, and 0.9 mm shell thickness. These settings are most important for the breadboard clips, as these may break off if the infill is too weak.