In order to inform initial design direction, I decided to have a look online for existing designs. Here are some examples of existing Raspberry Pi Zero Enclosures…
The case shown in Figure 2 (showing a Raspberry Pi Zero enclosure (Makerspot, 2016: Online)) appears to be injection moulded and is split through the middle, allowing the user to easily access the ports without having to remove the board completely. A slot has been moulded into the top half of the case to allow wires to be threaded through whilst the case is closed and rubber feet are also provided for use on a surface.
This Case (Figure 3, showing a 3D Printed Adafruit Raspberry Pi Zero case (Raspberry Pi Spy, 2015: Online)) has been 3D printed. However, instead of the case being split in half, a lid covers a larger cavity in which the board in housed. Whilst access or removal may be more difficult, a lid may be easier to fasten, since the board is less of an obstruction (although this lid appears to be friction/snap fit). This is a more suitable design for when frequent removal is not required.
This Enclosure (Figure 4 showing a Raspberry Pi Zero enclosure (Hobby Components, 2020: Online)) looks as though it has been constructed using two laser cut pieces of acrylic. These components are stacked, with the board and spacers in the middle, and fastened together with nuts and bolts. A disadvantage of this design is that full access/removal of the board requires the components to be fully disassembled. However, the more open design would allow much more ventilation, since air can flow freely through the assembly, over both sides of the board.
This case (Figure 5 showing a KKSB Raspberry Pi Zero case (KKSB, 2019: Online)) has a considerably different construction. The two parts of the enclosure appear to be cut from a sheet of metal and bent into shape. Only two opposing walls of the case are attached to each part. The end faces are attached to the base, where the board would be fastened in, enabling easy access without complete removal, and allowing good ventilation. The holes at the corners of the case indicate that the parts are assembled using bolts, making it more difficult to deconstruct. However, the clever use of only two (out of four) bolts to fasten the case together means that when removed, the remaining two bolts stay in place to prevent the board from falling off during deconstruction.
This is another different design (shown in Figure 6, a Flick Zero case (Farnell, 2017: Online)) (although appears to be similar to the previous enclosure). The lid is split in two, each part slotting into the base, not only providing a covering for the top but also the ends of the enclosure. The larger sides that are attached to the base may obstruct access to the board. However, the design could be adapted for easier use. A slot could be cut from the meeting edges of the lid components, allowing wires attached to the board to be collected easily whilst the case is being closed, rather than threaded through a single lid (as in previous designs), facilitating easier use. Secondly, instead of slotting into the base, the lid parts could rotate from the bottom corners of the base and fasten in the middle, which may also improve user experience.
Looking at these existing products will inform some design concepts of my own, transferring strengths of some designs whilst learning from their weaknesses.
Figure 1: Sanabria-Diaz, A. (2016) RetroPie Setup on the Raspberry Pi Zero. Black Brick Software. [Online Image] [Accessed on 22/10/2020] https://blackbricksoftware.com/bit-on-bytes/143-retropie-setup-on-the-raspberry-pi-zero-v1-3
Figure 2: Makerspot. (2016) Raspberry PI Zero Enclosure. [Online Image] [Accessed on 22/10/2020] https://makerspot.com/raspberry-pi-zero-enclosure-compatible-with-pizero-w/#reviews
Figure 3: Raspberry Pi Spy. (2015) 3D Printed Adafruit Raspberryy Pi Zero Case. [Online image] [Accessed on 22/10/2020] https://www.raspberrypi-spy.co.uk/2015/12/3d-printed-adafruit-raspberryy-pi-zero-case/
Figure 4: Hobby Components. (2020) Raspberry Pi Zero Enclosure. [Online Image] [Accessed on 22/10/2020] https://hobbycomponents.com/enclosures/762-raspberry-pi-zero-enclosure-hcrasp0020-22
Figure 5: KKSB. (2019) KKSB Raspberry Pi ZERO Case. [Online Image] [Accessed on 22/10/2020] https://kksb-cases.com/products/kksb-raspberry-zero-case
Figure 6: Farnell. (2017) Flick Zero Case. [Online Image] [Accessed on 22/10/2020] https://uk.farnell.com/pi-supply/flick-zero-case/flick-zero-case-orange-white/dp/2799636