Hello everyone, and welcome back to another weekly design challenge summary. It’s the eleventh week of the PiCasso Design Challenge and the third week of the Experimenting with Polymer Capacitors Design Challenge (. Lots of progress has been made over the past week, but before we get to the good stuff, let’s take a few moments to learn more about these challenges, their challengers, and what hardware is being featured. 


PiCasso Design Challenge


About The Challenge


Featured as the first Design Challenge of 2019, this challenge task its twenty participants with creating their artistic masterpiece using a Raspberry Pi Model 3B+. Challengers can either push their boundaries by using the computing power of Pi as the brains of their artistic work or to improve the aesthetics of their surroundings.


While twenty project proposals were chosen to be the official projects of the challenge, entering the challenge is not limited to just those twenty community members. Anyone can join the Challenge as a non-sponsored Challenger, and still be eligible win one of the three prizes. If you are a non-sponsored challenger all you need to do is integrate the components from the official challenger kit into your design, and post 10-weekly blogs detailing your project’s build.



The Official Kit


The PiCasso Design Challenge is sponsored by the Raspberry Pi Foundation. Each challenger will receive all of the components below plus a wide assortment of additional passive, and digital components to build their projects with. If you would like to enter the challenge for yourself, or if you just want to follow along at home, you can purchase all of the components in the kit right here at Element14.



To learn more about each of these components as well as the other components included in the kit, visit the official kit announcement page or click the links above to purchase them for your project.

The Prizes

      • Grand Prize: DJI Mavic 2 Pro Videography Drone
      • Runner Up Prize: Nikon D3500 DSLR & Lens Kit
      • Finisher Prize: Raspberry Pi Arcade Kit. To be eligible, a challenger has to complete their project, use products from the challenger kit, and post at least 10 updates in the Sixth Sense Design Challenge space.


To learn more about the prizes, head over to the PiCasso Design Challenge Prize Page.



The Past Week In Review


Over the past several days, May 19th - May 25th, we have had a total of twelve updates posted across nine projects. I will be highlighting three of my favorite updates from this past week, but before I get to that, let's take a look at which projects were updated. 




This Week’s Top Updates


Project: Hologram Pi-ramid - PiCasso Design Challenge Blog  #6 - PCB Design



Claiming the top spot in my list this week is project Pi-ramid’s sixth update. This week Luis focused on the custom PCBs that will add RGB lighting to the Pi-ramid, as well as a quick and easy way to connect other electronic modules in the future. The design originally featured addressable RGB LED strips on the left and right sides of the Pi-ramid, but Luis decided to remove them due to fears that their operation might interfere with users who might be viewing a hologram from the sides. “On the initial Hologram Pi-ramid design, I had in mind including side RGB lights. These lights may shine right in front of someone looking inside the pyramid from the sides, disturbing the hologram perception so this idea was discarded,” he wrote. Luis wrapped up the post by highlighting a feature in Autodesk Fusion 360 that allows you to remove design elements from the timeline of the design, which makes changing aspects of the design on the fly much easier than with other 3D design programs. Click the link above to read the full post.



Project: ASmart Home Orchestra And Mood Mediator - PiCasso Design Challenge Blog #7 - Playing with TensorFlow Magenta



In the seventh update to project SHOAMM Sergey Vlasov walks us through his experimentation with a python library called Magenta which was created by Google for its TensorFlow AI and generates visual art and music. The Hello Magenta Colab Notebook was used to get started as it allowed Sergey to run the python scripts in his browser as well as offloading the processing duties to Google’s servers. “There are several options to Get Started with Magenta.I decided to start with Hello Magenta Colab Notebook as it is using Python and it is a way to set up a Python environment in the browser without installing it locally. In addition Google provides runtime environment and GPU to test it out,” Sergey wrote. Head over to the full post to see some examples of the code sergey wrote to generate music based on temperature and other sensors.



Project: POV Globe - PiCasso Design Challenge Blog  #9 - Completion



Our final update this week for the Picasso Design Challenge comes from Dale Windhold and his project, POV Globe. With just about a week left in the challenge, Dale has reached the finish line a little early, and took the time to test everything out before making his 10th and final update this coming week. “With the challenge coming to an end in just over a week it is time to post my 9th blog. I have spent the last week setting up the Raspberry Pi, electrical, testing power transfer through the bearings and creating a backup just in case it fails. I got the LED's up and running with the Raspberry Pi attached in place,” he wrote. “The project is complete except for the final programming of my display. Below are pictures of the project built to completion and how it will look finished. The last blog will include the python code and video of the completed/running project.” I for one am excited to see the POV Globe in action next week, but until then, I would suggest that you click the link above to check out the complete update.



Experimenting with Polymer Capacitors Design Challenge


About The Challenge


The Experimenting with Polymer Capacitors Design Challenge is a new type of challenge for 2019, this challenge is a hands-on competition that everyone in the community can participate in. Instead of requiring a participant to produce a full prototype, project, or original circuit design, we decided that we'd give our members the opportunity in this competition to experiment, test, breadboard, or just play around with Polymer Capacitors, and then tell us about their experiments, and what they learned about Polymers Capacitors in some blog postings.


While only nine sponsored challengers were chosen to receive a free polymer capacitor kit, entering the challenge is not limited to just those nine community members. Anyone can join the competition by including at least one of the kit's polymer capacitors in his/her experiments



The Official Kit


Nine Challengers received a discrete component kit that included several different types of capacitors that can be used to experiment with. As the list is quite long, I am not going to post it here. If you are interested in purchasing the kit for yourself, please visit this link.



The Prizes



To learn more about the prizes, head over to the this page. (https://www.element14.com/community/docs/DOC-92091/l/experimenting-with-polymer-capacitors-about-the-competition)



The Past Week In Review


Over the past several days, May 19th - May 25th, we have had a total of eight updates posted across five projects. This week I will feature three of my favorite updates from this time period, but before I get to that, let's take a look at which projects were updated. 




This Week’s Top Updates


14RHB  - Experimenting with Polymer Capacitors Blog  #4 - PCB Making



Following up on his first update post, 14RHB spent the last week etching a custom PCB for the polymer capacitor based power supply. To get things started he printed out his PCB design onto a piece of paper using a laser printer, and then used a UV lightbox to expose the PCB’s traces onto a photosensitive FR4. A chemical developer was then used to wash away all of the unexposed UV film, before the whole PCB was placed in Ferric Chloride to etch away the exposed copper layer. Unfortunately the FR4 board that 14RHB used was old and defective, and he was forced to re-expose the board design onto a new piece of FR4 and start the whole process all over again.


“All seemed to be going well until I noticed the jagged edges forming. I instantly knew why that was. As my design could be created on a single side board I had found an old piece of pre-sensitised PCB in the shed and used that. This was a board I had purchased from Ebay and quickly found it to be unusable - for some reason I kept a piece for RF work,” he wrote. “I believe the issue is that the board structure itself consisted of many microscopic scalloped grooves, which once laminated with copper caused that too to have a scalloped surface...almost indistinguishable. However once coated with UV resist this resulted in thick and thin strips of resist which would be impossible to expose and develop evenly.” The results were much different after the second run, but you will have to head over to the full post at the link above if you want to find out how the second try turned out.



Frank Milburn  - Experimenting with Polymer Capacitors Blog  #2 - Deep Dive Into ESR: Testing



If you were impressed with Frank Milburn’s previous project update where he went into detail and educated us all on ESR, you are going to really enjoy his second installment in the series. This week Frank covers how to properly test ESR using an ESR meter, a cheap “MTester” from China, as well as how to test ESR using an Oscilloscope. In the end the results were better than expected with Frank noting: “The measured ESR of the Panasonic polymer capacitors was at or below the maximum listed in the datasheet in all instances,” he wrote. “The maximum values listed in the table and plotted above for electrolytic capacitors are actually "typical" values from the ESR70 manual and in all cases the measured ESR was below these values." However, due to inaccuracies in the testing methods at the very low ESR values the results should probably be looked at more as good or not-good for both the ESR70 and oscilloscope method. The capacitors all appear to be good.This post is just as informative as his previous update, and I highly suggest reading through it a few times, then watching the demonstration video that Frank included. Check out the full post by clicking on the link above.



Ralph Yamamoto  - Experimenting with Polymer Capacitors Blog  #4 - Buck Converter Tests



One of my favorite things about the Design Challenge series her at Element14 is the knowledge that is freely shared with not only the community, but the world at large, and that is why this particular challenge is quickly becoming one of my favorites. My final featured update this week comes from Ralph Yamamoto’s experiments with polymer capacitors and buck converters. To set up the test, Ralph took a baseline ripple reading using an oscilloscope and a cheap buck converter from China. The ripple under load was fairly bad, but the big surprise came when it actually got worse after swapping out the standard electrolytic capacitors on the buck converter with a low ESR polymer capacitors. After some digging, Ralph found the reason for this. “It appears that I created an instability with too low an ESR value!  I think at this point I think I've exhausted all the energy that I had allocated to this challenge.  I think in the future I'd like to simulate this design and try to fix it.  I think that I just need to find the correct value for a compensation cap in the feedback loop,” he wrote. Head over to the full update at the link above to view his data.




That is going to wrap up this weeks coverage of the Picasso Design Challenge and the Experimenting with Polymer Capacitors Design Challenge. If you have not yet done so, please take a moment and check out all of this weeks updates, and show our challengers some love in the comments section of each update post. Check back next week for another weekly design challenge summary..