It's years-belated, but I recently published the project page for an early prototype that I'm now several revisons beyond.
I learned a lot from creating GBGv1. I learned that the concept is fun, usable and something I wanted to share with others. I learned that I wanted to try to take things to the next level. To that end, I started reading and learning all I could to take a hobby project into the realm of "production-feasible."
This meant identifying key elements of the Glow Bean Glow Alpha that were "hacky."
Some of these include:
- Through-hole construction is not cost-effective for several reasons, including component cost, PCB size (cost) and last, but not least, assembly costs.
- V-USB, while absolutely great for hobbyists and prototypes, is not fully USB-compliant and not optimal for a consumer-ready design.
- Having LibUSB installed shouldn't be a requirement to use the host software. It's heavy-handed and unnecessary for something simple like Glow Bean.
- The Munny body, while completely awesome and (nearly) aesthetically perfect for this application, was not even remotely pragmatic from the perspective of manufacturing (unless someone from KidRobot is interested in working with me, in which case please contact me! Now back to our regularly-scheduled pragmatism...)
In order to address these, I decided that:
- The final design must utilize as many SMDs as possible. While GBGv2a and v2b both utilize through-hole button switches, the final version will be 100% SMT.
- V-USB had to go. I opted to use a microcontroller that had a legitmate USB PHY. After hours of research and prototyping, this became the ATmega32u2 with the LUFA USB stack. (Dean Camera, I thank you for your work)
- So, LibUSB is awesome, but frankly, it shouldn't be required for a consumer product. So it's out, and HID class is in. The USB HID (Human Interface Device) class is incredibly flexible, fairly simple, and offers ubiquitous support. Win.
- Replacing the Munny. Yeah, that's a tough one. For starters, everybody loves Munnys. But, it's time to put on the industrial designer cap and... well, learn industrial design. Turns out industrial design and materials manufacturing practices are not things you simply google. Well, technically you can (and I do), but distilling that information into usable chunks is pretty time-intensive and is still incomplete. This is something I'm still working on.
Fast forward from July 2011, I've got two GBGv2 PCB prototypes created and working, and I'm getting close to starting a third. I've got two different (but similar) enclosures prototyped and I'm hoping to hone those further as equipment access and research allows.
I'll post a project page soon with more information on GBGv2 and some photos, but here is a teaser: