In this case, additional feature requests were made that changed core parts of the design. Room needed to be added to accommodate an additional shield or board, as well as any wiring. This resulted in the case being expanded 10mm on the sides and increasing the height by 18mm. Time was also taken at this stage to refine existing features. The SD Card port was enlarged for easier access and the press-fit to close system improved alongside adding Greebling to the case top. This version of the Beagle Bone Case was then 3D Printed.
Unfortunately, there is a problem with the case as designed; it takes over 5hrs 30min to complete in addition to suffering from curling due to its new size. Internally, a design that takes longer than 180-225min to 3D print is no longer affordable to offer as a product. The time removes full 3D printing as an option for manufacturing after including the cost of running the 3D Printer and man power.
|Highlighting the curling on the edges.|
|MDF as Case Top in Composite Test|
Engineering asks that problems not only be solved by building something, but building it in a manner that is practically useful to all involved parties. This lead to the decision that the final version of the 3D Printed Case can still be offered to the community via Thingiverse to do with as they please and a new method of housing the Beagle Bone on the TurtleBot must be created. Another alternative would be to outsource the handling of the 3D Printing to a partner like Shapeways or travelling down the road of injection molding with services like Protomold. The injection molding route may yield the best results, but it comes with it's own requirements so the case will enter another lengthy design phase. In both situations, crowd sourcing initial interest would be the smartest way to judge whether its a worthwhile endeavor.
To reach this point, over 6 versions of the Beagle Bone Case were created, not including any of the test parts used. The project spanned 10 regular working days. More than 24 hours of actual 3D Printing Time were logged.
|Overview of various case part iterations|
|Testing Inserts Effect on Acrylic|
Fortunately, we already have all the necessary dimensions and constraints on hand due to earlier work. Because this makes creating the adapter a much faster process, there was a realization that we can make this adapter plate universal between several development boards at once. What started as an idea to build cases for boards that had universal mounting points, is now a simple adapter plate that works with the Beagle Bone, Raspberry Pi, and Arduino suite of Boards.
The adapter is made of 1/4" thick Acrylic featuring 16 Brass Heated Inserts for 4 different hole patterns that comfortably accommodates the Beagle Bone, Raspberry Pi, and Arduino suite of Boards. It comes ready with Board Adapter Plate, (4) M3 1/4" spacers, (2) M2.5 1/4" spacers, (6) 10mm M3 socket head screws, (2) 10mm M2.5 socket head screws, and (4) 10mm M4 thumbscrews.
Pre-Oder your TurtleBot Universal Board Adapter here [Lead Time: 1 week]: http://store.iheartengineering.com/robots/turtlebot/accessories/ihe-2101-0003-0000.html