2018-06-18 4 min read


Planning & Strategy.

  • So apparently there's a company called SpinLaunch, and they're trying to launch satellites using what is basically a centrifuge with a door on one side. The idea here is that you build this big centrifuge so that it's at (say) a 45* angle to the horizon and then use it to accelerate a small payload up to (say) tens of thousands of revolutions per minute. You do this all with electricity - no rockets. Then, when the payload is going fast enough, you open a hatch door on the outside of the centrifuge and it *screams* out, its momentum carrying it into or close to orbit. The amount of energy we're talking about here is crazy (I hear SpinLaunch's demo involves blasting a payload into a big steel wall, and that it's *terrifying*), and the centripetal forces on the payload while it's in the centrifuge would be *way* greater than what a traditional rocket experiences. But, it could eliminate or greatly reduce chemical propellants from non-human launches, putting a lot of the stuff that traditional launchers contain (rocket engines, fuel tanks, lots of kerosene and oxygen) out of the picture. I think the whole idea sounds totally crazy, but maybe...?
  • The Chinese battery company CATL raised nearly $1B last week. "China will be making 70 percent of the world’s electric-vehicle batteries by 2021."
  • Uber, Lyft, and Via are fighting NYC T&LC's mandate that 25% of their cars be wheelchair accessible by 2023.
  • Tesla is laying off 9% of their employees. Production workers are apparently unaffected; see below for more Musk-related stuff.

Making & Manufacturing.

  • Cold metal transfer is a type of GMAW (often known as MIG welding) in which current is reduced (or inverted) and the wire is retracted as soon as a short circuit is detected. It results in welds that look a lot like GTAW (aka TIG) - nice, fine beads, but laid without a separate tungsten electrode. This video from Fronius does a decent job of explaining.
  • A good overview of a variety of abrasive machining techniques.
  • Autodesk is looking for Pier 9 "residents who will share their work as it relates to the configurable microfactory vision."

Maintenance, Repair & Operations.

  • A new study estimates that direct air carbon capture (extracting CO2 directly from the atmosphere, which would presumably be done in addition to scrubbing it from power plant emissions) would cost between $94 and $232 per ton of captured CO2, which is already cheap enough to be profitable in some areas. "Making direct air capture as cheap as possible is critical because a growing body of work finds it’s going to be nearly impossible to prevent global temperatures from rising more than 1.5 ˚C without rolling out some form of the technology on a huge scale. By some estimates, the world will emit enough greenhouse gases to lock in that level of warming within a few years. At that point, one of the only ways to reverse the effects is to remove carbon dioxide from the atmosphere, where it otherwise persists for thousands of years."

Distribution & Logistics.

  • Rahm Emanuel is moving forward with Elon Musk's Boring Company on their proposal to build a high speed link between O'Hare and The Loop. I recommend reading The Chicago Tribune's piece on this, which goes through a lot of the historical detail and gives, I think, a pretty balanced (or perhaps a little kind to Musk - is his "tunneling technology" really "highly touted"?) assessment of the whole deal. I also recommend the Verge's skeptical take on the project cost (TL;DR: How exactly is Musk, who is using off-the-shelf hardware and whose track record is looking decidedly mixed right now, going to come in at 1/10th the cost of similar projects?). And for a more strategic perspective, see Jarrett Walker's 2016 piece on the Toronto airport express and the qualities that make for successful airport rail connections (thru routes rather than cul-de-sacs, integration into as many other forms of transit as possible, making sure that the pricing & routes serve airport workers as well as possible).
  • Two good pieces on the Faroe Islands: One on the impressive investments they've made in intra-island tunnels, and one on their postal system, which is both cute and critical to keeping the rocky and barely inhabited islands functioning as a single entity.
  • Swarm, which violated FCC rules by launching unpermitted satellites into orbit, is asking for a new permit. You'll recall that the FCC was worried that Swarm's satellites would be impossible to track, increasing the risk that they'd crash into something else in orbit. Editor's note: The idea that space startups will self regulate is just silly.

Inspection, Testing & Analysis.

  • For some reason Nathan Mhyrvold (former CTO of Microsoft but probably better known for Intellectual Ventures, which is a rad place but also does some arguably unsavory stuff with patents) is picking a fight with NASA scientists re: their catalog of asteroids and their sizes. I don't really get what his angle is here - is it an altruistic thing, as if humanity is at risk if we miscalculate this particular dataset? Is there some financial upside? Is it just about being right?
  • A good explainer on the aerodynamic forces at play on bicycle spokes, and the rationale for varying spoke cross section in order to minimize drag under all conditions.


A mini-collection of stepper motor demo videos.

Read the full story

The rest of this post is for SOW Subscribers (free or paid) only. Sign up now to read the full story and get access to all subscriber-only posts.

Sign up now
Already have an account? Sign in
Great! You’ve successfully signed up.
Welcome back! You've successfully signed in.
You've successfully subscribed to Scope of Work.
Your link has expired.
Success! Check your email for magic link to sign-in.
Success! Your billing info has been updated.
Your billing was not updated.