Reading List 05/10/2025
Amazon’s Vulcan robot, magnetohydrodynamic ship propulsion, Waymo’s manufacturing scale up, Boom Supersonic’s new super alloy, and more.
Welcome to the reading list, a weekly roundup of news and links related to buildings, infrastructure, and industrial technology. This week we look at Amazon’s Vulcan robot, magnetohydrodynamic ship propulsion, Waymo’s manufacturing scale up, Boom Supersonic’s new super alloy, and more. Roughly 2/3rds of the reading list is paywalled, so for full access become a paid subscriber.
Inspired by one of my favorite Twitter threads of all time, I started a new Twitter account dedicated to sharing pictures of “Infrastructure that looks like Sci Fi”. You can follow it here.
Shipbuilding reading list
This week’s newsletter was about US shipbuilding during WWII. For those who want to read more about the subject, here’s a list of some of the best references I found.
Ships for Victory by Frederic Lane - A very thorough 800+ page history of Maritime Commission shipbuilding during WWII. By far the most useful source on understanding the Maritime Commission shipbuilding program, though it’s a dense and dry read. Most other sources ultimately reference this one.
Launching a Thousand Ships by Chris Tassava - This is a 2003 phD thesis on US WWII shipbuilding. Covers a lot of the same ground as Lane’s book (and references it heavily), but it has much more of a focus on the actual shipbuilding methods used, and Henry Kaiser, operator of the largest and most efficient shipyards. For learning about Maritime Commission shipbuilding, this and Lane together are almost all you need.
Freedom’s Forge by Arthur Herman - The very popular history of US WWII mobilization that emphasizes the role of businessmen like Bill Knudsen, Henry Kaiser, and Henry Ford. It’s a good and useful source, and probably the only book here of interest to the general reader, but it gives a very narrow perspective on the subject. So for shipbuilding there’s lots of coverage of Kaiser, but virtually no mention of other builders like Bethlehem, even though Bethlehem built a large chunk of both Maritime Commission ships and ships for the Navy. Recommended reading in concert with other sources that give a broader view.
Historical American Engineering Record Report on Richmond Shipyards - Exactly what it says on the tin, a historical report from HAER on the Kaiser Richmond shipyards. This had a lot of interesting detail on the background of WWII shipbuilding (including its WWI prehistory) and the Kaiser yards themselves that other sources didn’t.
Calship Liberty Ship Manual - This is an interesting book produced by Calship in 1942 that details the layout of the yard and the exact procedure used to build a Liberty Ship, complete with pictures of the various processes and prefabricated sections.
Amazon’s Vulcan robot
I noted in my essay about humanoid robots that dexterity — the ability to flexibly manipulate a variety of objects quickly and precisely — is still difficult for robots, but that it seems to be improving. Amazon recently announced a robot system with what looks like impressive dexterity capabilities, though it’s not a humanoid robot nor does it use human-like hands. Vulcan is an Amazon robot that uses touch sensors (along with computer vision) to stow and retrieve objects from storage pallets. Via AboutAmazon:
In our fulfillment centers, we maximize efficiency by storing inventory in fabric-covered pods that are divided into compartments about a foot square, each of which holds up to 10 items on average. Fitting an item into or plucking one out of this crowded space has historically been challenging for robots that lack the natural dexterity of humans.
Vulcan is our first robot with a similar kind of finesse. Vulcan can easily manipulate objects within those compartments to make room for whatever it’s stowing, because it knows when it makes contact and how much force it’s applying and can stop short of doing any damage.
Vulcan does this using an “end of arm tooling” that resembles a ruler stuck onto a hair straightener, plus force feedback sensors that tell it how hard it’s pushing or how firmly it’s holding something, so it can stay below the point at which it risks doing damage.
The ruler bit pushes around the items already in those compartments to make room for whatever it wants to add. The arms of the hair straightener (the “paddles”) hold the item to be added, adjusting their grip strength based on the item’s size and shape, then use built-in conveyor belts to zhoop the item into the bin.
For picking items from those bins, Vulcan uses an arm that carries a camera and a suction cup. The camera looks at the compartment and picks out the item to be grabbed, along with the best spot to hold it by. While the suction cup grabs it, the camera watches to make sure it took the right thing and only the right thing, avoiding what our engineers call the risk of “co-extracting non-target items.”
IEEE has a bit more detail about Vulcan’s stowing ability here, and picking ability here. A nice (short) video of the system in operation here.
Air traffic control
Recent problems at Newark Liberty Airport (12th busiest US airport by passenger volume) have highlighted major problems in the nation’s air traffic control system (not a sentence you ever want to have to write). From the Wall Street Journal:
At about 1:30 in the afternoon on April 28, air-traffic controllers overseeing the busy airspace around Newark Liberty International Airport suddenly faced a frightening scenario.
The chatter from pilots they were communicating with went silent. Radar screens filled with dots showing aircraft positions went dark. Backup systems failed. Planes bound for the area went into holding patterns.
About 90 seconds later, the traffic-control systems started blinking back to life. But problems lingered with the radar, and controllers worried the radios would go out again…
There were no crashes, but scores of flights coming and going were delayed for hours, and dozens scheduled to arrive in Newark were diverted to other airports…
America’s air-traffic control system has been troubled for years, the culmination of years of anemic funding, archaic technology and staffing problems. A wake-up call sounded on Jan. 29 with a midair collision near the Ronald Reagan Washington National Airport that killed 67 people. President Trump and Transportation Secretary Sean Duffy have pledged to overhaul the system.
The Government Accountability Office said last year that about three-quarters of the FAA’s 138 air-traffic systems were either obsolete or potentially too difficult to reliably maintain. Duffy said he is preparing to unveil a plan this week to upgrade the FAA’s network of facilities, radars and other technology, which industry and government officials believe could cost $20 billion to $40 billion.
Part of the problem seems to be a shortage of air traffic controllers, as the New York Times notes:
The nation’s air traffic control system has been plagued by years of dysfunction. The controller ranks were depleted by retirements and a cessation in training during the pandemic. Since then, recruiting and certifying new controllers has been difficult. Existing controllers have been fatigued and even sickened by intense stress and long hours, The New York Times has reported. Some have avoided seeking medical attention because doing so could jeopardize the health care clearances they need to do the work. Turnover is frequent, especially amid illnesses, family turmoil or safety scares.
This shortage was probably exacerbated by an extremely misguided attempt by the FAA to change its hiring policies to increase the diversity of aircraft controllers.
Magnetohydrodynamic ship propulsion
The Hunt for Red October is a movie, based on a Tom Clancy book, where a Russian sub commander tries to defect while operating a new sub with a nearly silent “magnetohydrodynamic” (MHD) engine with no moving parts. Apparently this engine is based on a real idea. The a post at K&J Magnetics explains how a MHD ship drive works:
Salty water conducts electricity. Imagine a drive tube with two conductive plates secured on opposite sides of the tube. With one grounded and the other connected to a voltage, a current flows through the water across the gap.
The resistance of the water changes depending on how much salt is dissolved in it. The more salt, the more current you'll get. Since submarines operate in the ocean, we'll assume the operating fluid is seawater, roughly 3.5% salt by weight.
Next, we'll place two magnets sandwiching the tube, top and bottom. Now the water within sees vertical magnetic field.
Finally, let's consider the Lorentz force. Consider what's happening to a tiny little bit of conductive water within that tube. The right hand rule says that, with a current flowing in one direction, and a magnetic field runs in a direction perpendicular to that electric flow, then the bit of water will feel a force that's perpendicular to both of those directions.
Whew, that's a mouthful. Let's express that graphically with the right-hand rule. If the current runs in the direction of the thumb, and the magnetic field with the index finger, the force is down the middle finger.
An experimental ship using a MHD drive was built in Japan in the 1990s, but the technology never apparently progressed after that. But apparently since 2023 DARPA has been working on a MHD program, enabled in part by advances in magnets from commercial fusion companies. Via New Atlas:
…if this technology is so valuable, why hasn't it been used for over 60 years except in a couple of experimental surface boats? The answer is twofold. First, the electromagnetic coils need to be extremely powerful and making ones that are light enough and efficient enough to install in a submarine isn't easy. The second is that the electrodes must stand up to a lot of wear due to corrosion, hydrolysis, and erosion caused by the interaction of the magnetic fields, electrical current, and saltwater…
"The best efficiency demonstrated in a magnetohydrodynamic drive to date was 1992 on the Yamato-1, a 30-m (100-ft) vessel that achieved 6.6 knots with an efficiency of around 30% using a magnetic field strength of approximately 4 Tesla," said Susan Swithenbank, PUMP program manager in DARPA’s Defense Sciences Office. “In the last couple years, the commercial fusion industry has made advances in Rare-Earth Barium Copper Oxide (REBCO) magnets that have demonstrated large-scale magnetic fields as high as 20 Tesla that could potentially yield 90% efficiency in a magnetohydrodynamic drive, which is worth pursuing. Now that the glass ceiling in high magnetic field generation has been broken, PUMP aims to achieve a breakthrough to solve the electrode materials challenge."