Raspberry Pi and PiBow on a diet

As the first phase of the drone project nears an end, I’m looking at some non-technical fine tuning; specifically, can I make the RPi and it’s PiBow like custom case any smaller and lighter?

First step is was to flatten the RPi Model A – the drone has no need of audio output nor analogue video, so both of those are gone.  Also the GPIO pins have been replaced by a crimp connector directly soldered to the board.   Now the tallest thing on the board is the cylindrical electrolytic capacitor near the micro-USB power plug.

Lighter, thinner Raspberry Pi

Diet Raspberry Pi – losing weight and getting thinner

Next step is to start from the Model B PiBow case design, and take out two of the rows, and modify several of the others to close the holes for audio, video and ethernet, move the GPIO cable hole lower, and redesign the camera CSI cable outlet.  As a first step I needed to test the fit of the skinny RPi model A in the standard PiBow model B case:

Model B weightloss

Planning surgery for weight loss on the Model B PiBow

In addition, I found this super micro-SD to SD adapter which meant I could close the SD hole on the case reducing the risk of the SD card being damaged or falling out during a flight – a low risk, yes, but me and Murphy’s law are long standing acquaintances!

I picked up a second hand, unused copy of Adobe Illustrator CS2 for £40 off ebay (the current one is many hundreds).  So I made the tweaks mentioned above to the standard PiBow using it, and got it cut by http://www.cut-tec.co.uk/.

Here’s the end result: a model A height card, but minimal holes in the lid, bolts in the corners, micro-SD card locked in, audio and video holes shut, and GPIO and camera cables fed neatly out the sides.  I’m well chuffed.  I’m only going to fit it though once quadcopter is stable!

Custom model A case

Custom model A case

What do you get when you cross a Raspberry Pi, a PiBow and a Steamroller?

In preparation for getting a camera board to sling under my drone, I’m in the process of tweaking a RaspberryPi Model A, and designing my own variant of the PiBow case to match – although in doing so, I’ve found much broader use…

For the RPi changes, I’ve removed the A/V socket, and replaced the GPIO pins with an IDT connector so I can lose a couple of layers in the Model B PiBow. That’s now complete – removing the A/V connector wasn’t too bad, but removing the GPIO pins was a right PITA – more on that in another post. Here’s the end result.

For the PiBow, I wanted a cross between the Model B and Model A PiBows: thinner like the model A, but with bolts in the corner like the model B so it could be a direct but thinner replacement for the Model B Ninja PiBows I’m using at the mo on the drone and its RC. Primarily this is to reduce the weight, centre of gravity, profile and power consumption of both.

In the end, I had to compromise, and took 2 layers out of the model B, and sealed up the A/V socket, and opened up the GPIO hole to allow the larger GPIO connectors. I got a local laser cutter company to produce this from my Pibow001-AB3. Here’s what it looks like….

PiBow A + PiBow B

PiBow A + PiBow B cross

Note the addition of the IDC connector isn’t mandatory – there are 90 degree sets of pins available, and they were my first choice, but for the connectors on the ribbon cable, the 90 degree pins weren’t quite long enough.  They would still take the single wire pin connectors though if that’s what you’re after.