So a final update. Unfortunately i didn't get a video of everything running together before the close of the competition. I had it all running but i didn't get a chance to make a final video of it. I was preparing to do that when i get them email notifying it had closed 
. I did however do it last weekend and it can be seen on my usual YouTube channel:
I've also added the final version of my code onto my github:
The major changes in the code base were that i had too add some logic running the motor to move in small steps (10 degrees) at a time otherwise the inertia was a bit much for the centre. I also had to add the code for invoking the motor and grinder from the voice activation code.
Some final thoughts:
When i laid out this project it was never meant to be easy and as usual i was biting off more than i can chew. I'm pretty happy with how far i made it into the build. I've learnt a lot in the process as well; mostly how much i don't know and the experience i lack. One major area i would love to improve my skills is in electronics; specifically circuit design. I would also love to get more experience with manufacturing, though unfortunately I would need a much better equipment and i don't have the space at my current house. It was also great having a play and an explore with all of the bits and pieces of software; Alexa, Google Assistant and motion for raspberry Pi.
Some Sundays i had very little motivation to work on the project (perhaps influenced by hangovers) but overall i had a great experience working on this project.
A big thanks to Element 14 for selecting me as a sponsored challenger and a big thanks to the community for your feedback. Hopefully i will be soon doing another design challenge with a more practical project.
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