The ClockClock Project
Conclusion
This project turned out to be substantially more work that I originally thought it would when I started. The vast majority of my time was spent with the physical build and the wiring. It also took me a while to come up with a solid working movement design. The FPGA and Arduino designs actually came together with minimal hiccups.
Using the Qwiic connector on the Au to talk to a microcontroller is likely to be one of its most useful use cases. I was pleasantly surprised by how easy it was to set up on the Arduino side having never used Qwiic (or I2C) on an Arduino before.
There are a few things that could be improved if someone were to make another one of these.
First, the clock is pretty loud. The individual motors are all pretty quiet, but then you glue them to a pretty thin piece of wood it really amplifies it. I should have looked into some kind of sound dampening way to mount the motors. Maybe using some kind of soft rubber glue instead of super glue to attach them. The wood is also only 1.5mm thick for most of the face which really makes it reverberate.
I’m thinking I may try to pour liquid rubber onto the backside of the board to help dampen the noise.
The other major issue is that the stepper motors are internally geared and the gearing has backlash. This means that depending on the direction the hand was moving it may or may not be where it is supposed to be. They seem to get off a few degrees when switching directions due to the play. It isn’t the end of the world but it is off just enough to be painfully obvious. I may be able to write some code that could compensate for it but it isn’t consistent across motors and would have to be fine tuned.
This could be fixed with motors that aren’t geared. I had a hard time finding small stepper motors for this though that weren’t prohibitively expensive.
I hope this demo project has given you a good example of what can be done with an FPGA and hopefully sparks some ideas for your own projects!