It was a tough squeeze getting everything in there. The Robie chassis, while spacious is a bit awkwardly shaped. You have to keep wires clear of the moving parts like the wheels and switches. And the head imposes height restrictions.
If you look closely you'll note that the power bank has been shaved down in height. This is because it wouldn't fit vertically otherwise. Basically I pried open the case and separated the batteries and logic board (ie that part I fried the other day). I used a Dremel to saw off the top of the case that contained the logic board. This shortened it significantly while still allowing me to use it as a protective casing for the batteries. Before I snapped the case back together I drilled some holes on one side and secured it to the chassis with screws and nuts.
The Raspberry Pi is secured to the chassis with only a single screw at the moment. You'll note though that the mounting holes overhang the battery compartment with a space in between them. So I will secure this a bit better with some spacers. I just don't have them yet. Thanks to the magic of Ebay they are on order though!
The motor controller and DC-DC step up modules are also mounted with only a single screw. This is also not such a great situation for ruggedness. At the moment I think my best option is to use some double-sided tape in addition to the screw. This should keep everything in place a bit better.
So you may be wondering what the DC-DC step up module is all about. My thought process on that one is basically the original Robie ran off of 6 volts from the battery. USB power will give me 5 volts. Robie isn't exactly fast at the best of times, so I wanted to make sure I was supplying enough current to wheels. The step up module allows me to dial in the voltage with a screw driver. Unfortunately there are no identifying markers on the motors. So I really have no idea what the specs are. So I set the voltage at 6.25 (assuming they built in a bit of wiggle room at the factory).
So far I haven't managed to burn out the motors and he seems to move around ok!
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