2022-03-28 5 min read


Notes, 2022-03-28.

For the past six months, I’ve been working on the detailed design of a new hardware product. There are a seemingly endless number of decisions to be made, and I’m reminded of the iron triangle of project management—that projects are triple constrained by quality, cost, and time. My biggest enemy right now is time. With enough time, I know I could create a higher quality product at a lower cost, and that’s what makes finalizing it for production bittersweet.

A more nuanced way to evaluate designs would probably be a radar chart, with each axis representing a performance metric and the design goal being to maximize area filled in. But even so, the realist in me knows that there would be tradeoffs. There’s the design engineer in me who wants the product to look good. The manufacturing engineer in me who knows that certain features incur expensive custom tooling. The sustaining engineer in me who knows that my product will have to be supported for years to come. Without those perspectives adding axes to the chart and pulling in their respective directions, the end result would be fragmented.

Whatever you are working on, there are always going to be tradeoffs–but I hope you optimize it with a passion.

-Sean Kelley

The most clicked link from last week's issue (~7% of opens) was a real-time map of energy production & distribution data in 150 countries. In the Members' weekly lunchtime Zoom chat, we're talking about automatic bike suspension systems, anechoic chambers, and the Swedish national waffle day.

Planning & Strategy.

Making & Manufacturing.

Maintenance, Repair & Operations.

  • An overview of the soon-to-be-completed £18 billion Crossrail project, which will allow 1.5 million more people to commute to central London within 45 minutes. The 42 km (26 miles) of tunnel were completed in 2015 with the help of 8 separate tunnel boring machines, marvels of engineering themselves. While cost overruns and delays are common in infrastructure projects of this scale, a bigger question now is whether the investment will pay off given shifting commute patterns since COVID. Regardless, I look forward to riding it one day.
  • Python’s motto is “batteries included,” coming with a comprehensive standard library. Python is considering the removal of “dead batteries” within its code – technical debt that has accumulated over time and is no longer actively maintained. However, they are finding that even outdated modules still have supporters and dependencies that make removal difficult.

Distribution & Logistics.

  • Staxxon makes folding shipping containers that can shrink 5 empty containers into the size of one. This short video, from 2011, shows an initial prototype being folded. Staxxon isn’t the only company to have had this idea; a quick search returns several competitors. Nevertheless, it strikes me that if ever there was a time for this idea to succeed it is now, as empty containers pile up in ports at record levels. Currently, 40% of the containers in the Port of Los Angeles are sitting empty, a 5% increase over last year.

    Once a rigid design adds multiple joints that are exposed to the elements and transport damage, I would expect significantly higher maintenance costs and shorter useful life. Staxxon’s cost savings calculator abstracts this to a 1.5x multiple in maintenance cost. Since their containers are still in preorder, we will have to wait for data to confirm.
  • Raspberry Pi is selling its RP2040 microcontroller chips for discount in bulk. Meanwhile their flagship computer, the Raspberry Pi 4, is sold out via their approved resellers and selling for 4x the sticker price elsewhere. This highlights that the chip shortage can be quite product specific: one core component might be readily available, but another part is out of stock and as a result an entire assembly is off the shelf for months. As someone who has dealt with microcontroller shortages in the past year, having assurances of chip availability is critical. As a result, I expect the RP2040 to appear in more embedded projects moving forward.

Inspection, Testing & Analysis.


The cast iron structure of the U.S. Capitol dome.

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