2020-03-09

Notes, 2020-03-09.

Crazy times, huh?

On The Prepared's paid subscriber Slack, the discussion on COVID-19 has focused on three points:

• Lead times from Chinese PCB fabrication houses (including the one The Public Radio uses) have gone up, due partly to labor shortages and partly to production shifting to medical equipment for the Chinese government. US assemblers can switch to US PCB suppliers, but they're more expensive and, as Phil @ Adafruit alluded to, switching suppliers can be a little annoying.
• While companies that produce just-in-time and drop ship from China (like Apple) feel a short term pinch, most of the consumer electronics world operates on much longer timespans and might not feel the effects until later this spring or the 2020 holiday season.
• Even if production lines are back up to capacity, travel restrictions can *really* hurt new product ramp-up. Video conferencing hacks aside, the best way to guide someone through an assembly process is still to be standing next to them.

I vacillate, on the one hand feeling quite normal and on the other feeling like it's all about to wind out of control. And while I'm disappointed to be missing the opportunity to meet a few of you at the Open Hardware Summit on Friday, I am curious to tune in virtually and see whether a virtual conference really works.

The most clicked link from last week's issue (~14% of opens) was a video of the Valve Steam Controller manufacturing line.

Planning & Strategy.

• An open source rotary cell phone. Related, the 17 designs that Bell almost used for the layout of telephone buttons.
• Chinese scientists appear to be returning to China at higher rates than in previous years. Note, this article was written *before* COVID-19.
• McMaster-Carr's patent for a "system and method for browsing a product catalog and for dynamically generated product paths."

Making & Manufacturing.

• On textile manufacturing & automation:
• Ruth's visit to Fabdesigns, an engineering team that works specifically with 3D knitting.
• A rather boring video of an ultrasonic welding machine for textiles; the form factor is similar to a sewing machine and the process is controlled by a human operator.
• A video tour of a sock manufacturer.
• A product demo video of a fully automatic glove knitting machine, which functionally looks like a black box.
• The Ships AG YouTube channel, which features videos such as the HS C57S-4 welding bra sliders and the HS C5H-F8 attaching tape to a half open waist of briefs.
• A pithy little Twitter thread on techniques for integrating mechanical systems into the structure of a building. This relates to something I always think of when I see a 3D printed concrete house: Setting aside the global sand shortage, and the fact that the CO2 emissions from concrete are a *huge* problem, where exactly are all of the mechanical/electrical/other services supposed to go on these buildings? And if your answer is "embedded in the concrete," then how will you reconcile the projected labor savings from your concrete printing process with the huge amount of engineering & labor needed to fish PEX tubing through partially cured mud?
• A quick, satisfying gif of an open die forging.
• The Terex Corporation's page of materials processing equipment.
• A video tour of the process of making tofu, courtesy me watching YouTube with my daughter.

Maintenance, Repair & Operations.

• With a declining economic emphasis on agriculture, England is starting to let its rivers wind and wiggle again. It had never struck me that the agriculture industry would want rivers to run in straight lines, but of course they do and of course rivers are less healthy as a result. Related: I'm guilty of promoting the idea that the sinuosity of rivers approaches pi as time increased, which this article calls into question... but given the uncertainty due to the Coastline Paradox (from 2020-02-17), I wonder if the whole idea of river sinuosity is incoherent in the first place.

Distribution & Logistics.

• An overview of the push for automation at the loading dock, an environment which is typically too unstructured for robotics to work well.
• While Amazon does deliver to much of Africa, the couriers they use often do not provide doorstep delivery - leading many African customers to instead have their goods shipped to someone (a G.P.) in the US. These people then consolidate the packages, bring them as checked luggage on passenger flights, and coordinate with the recipients for hand delivery. G.P.s typically make $1300 per round trip flight for their services.
• The US eats a lot of chicken meat, and China eats a lot of chicken feet (aka paws), but neither country is able to get past themselves to make a really good trade deal. So today "most American chicken paws are now rendered for animal feed."
• A series of visualizations of FCC provided service contours for FM radio and TV.

Inspection, Testing & Analysis.

• From Alexis Madrigal and Robinson Meyer, a rather depressing look at the way that the CDC is handling COVID-19 testing.
• An analysis of historical data on LEGO set prices, piece counts, and weights. It turns out that average inflation-adjusted price per piece is down slightly over the years, but LEGO makes more high piece count sets - pushing the maximum price per set higher and (probably) leading to the perception that LEGO sets are getting more expensive.
• On ancient Roman plumbing valves, which are "strikingly similar to our modern design."

Tangents.

• Excavator keys for sale on eBay.
• An old Wait But Why piece on visualizing how you allocate your time.

Using color changing thread to verify knot theory predictions.