How it's made: I2CDriver

Over the next few days, I2CDriver will ship.

Here's some details on what's involved. We're assembling 1000 I2CDrivers in this batch, enough for the backers and to send stock to the distributors afterwards.

The units arrived from the manufacturer in Shenzhen (Boktech, they're great!) on Feb 4th, just before the colossal shutdown that is Chinese New Year. The I2CDrivers were in a single box, bubblewrapped in bundles of 10:


After unwrapping them, we load the firmware onto each unit. The back of each board has a bunch of contact points, so all that's involved is pushing it into the test frame, waiting 3 seconds, then putting the ID sticker on the back. The tester calibrates the analog components, customizes and builds the appropriate firmware, loads it onto the I2CDriver's microcontroller, and runs a short confidence test to make sure it's running properly.


As I've improved the process, the per-unit test time has gone from about 45 seconds to 18 seconds. That means we can get 200 units per hour processed through this step.

With the units loaded and tested, we have to attach the signal guide label, solder the headers, and attach the four 3M rubber feet. The students who help me can finish about 30 units an hour.  Materials and labor for these steps add a couple of dollars to the cost.


At this point, the I2CDrivers themselves are finished, and ready to package up. Along with the unit itself, the package includes a small setup card and the cable sets. The custom cables (ordered from Dirty Cables in December) get tucked into the bag in a (hopefully) neat package.


For the I2CDriver run, we have invested in an automatic bag sealer. A heated belt and roller seals the bag, then drops it off the end of the conveyor. The final action is to add a tear-open notch in the side of the bag. This notcher (meant for sewing patterns I think) does that:

That's it! The I2CDriver is ready to send out. If you're a backer, one of these will be reaching you in the next few days.

Thanks for reading - next week I'll talk about making the I2CDriver firmware.