The Engineering Of The Falkirk Wheel

We live in an age where engineering marvels are commonplace: airplanes crisscross the sky, skyscrapers grow like weeds, and spacecraft reach for the stars. But every so often, we see something unusual that makes us take a second look. The Falkirk Wheel is a great example, and, even better, it is functional art, as well.

The Wheel links two canals in Scotland. Before you click away, here’s the kicker: One canal is 35 meters higher than the other. Before 1933, the canals were connected with 11 locks. It took nearly a day to operate the locks to get a boat from one canal to the other. In the 1930s, there wasn’t enough traffic to maintain the locks, and they tore them out.

Fast Forward

In the 1990s, a team of architects led by [Tony Kettle] proposed building a wheel to transfer boats between the two canals. The original model was made from [Tony’s] daughter’s Lego bricks.

The idea is simple. Build a 35-meter wheel with two caissons, 180 degrees apart. Each caisson can hold 250,000 liters of water. To move a boat, you fill the caissons with 500 tonnes of water. Then you let a boat into one of them with its weight displacing an equal amount of water, so the caissons stay at the same weight.

Once you have a balanced system, you just spin the wheel to make a half turn. There are 10 motors that require 22.5 kilowatts, and each half-turn consumes about 1.5 kilowatt-hours.

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Practice Makes Perfect: The Wet Dress Rehearsal

If you’ve been even casually following NASA’s return to the Moon, you’re likely aware of the recent Wet Dress Rehearsal (WDR) for the Artemis II mission. You probably also heard that things didn’t go quite to plan: although the test was ultimately completed and the towering Space Launch System (SLS) rocket was fully loaded with propellant, a persistent liquid hydrogen leak and a few other incidental issues lead the space agency to delay further testing for at least a month while engineers make adjustments to the vehicle.

This constitutes a minor disappointment for fans of spaceflight, but when you’re strapping four astronauts onto more than five million pounds of propellants, there’s no such thing as being too cautious. In fact, there’s a school of thought that says if a WDR doesn’t shake loose some gremlins, you probably weren’t trying hard enough. Simulations and estimates only get you so far, the real thing is always more complex, and there’s bound to be something you didn’t account for ahead of time.

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PROFS: The Office Suite Of The 1980s

Today, we take office software suites for granted. But in the 1970s, you were lucky to have a typewriter and access to a photocopier. But in the early 1980s, IBM rolled out PROFS — the Professional Office System — to try to revolutionize the office. It was an offshoot of an earlier internal system. The system would hardly qualify as an office suite today, but for the time it was very advanced.

The key component was an editor you could use to input notes and e-mail messages. PROFS also kept your calendar and could provide databases like phonebooks. There were several key features of PROFS that would make it hard to recognize as productivity software today. For one thing, IBM terminals were screen-oriented. The central computer would load a form into your terminal, which you could fill out. Then you’d press send to transmit it back to the mainframe. That makes text editing, for example, a very different proposition since you work on a screen of data at any one time. In addition, while you could coordinate calendars and send e-mail, you could only do that with certain people.

A PROFS message from your inbox

In general,  PROFS connected everyone using your mainframe or, perhaps, a group of mainframes. In some cases, there might be gateways to other systems, but it wasn’t universal. However, it did have most of the major functions you’d expect from an e-mail system that was text-only, as you can see in the screenshot from a 1986 manual. PF keys, by the way, are what we would now call function keys.

The calendar was good, too. You could grant different users different access to your calendar. It was possible to just let people see when you were busy or mark events as confidential or personal.

You could actually operate PROFS using a command-line interface, and the PF keys were simply shorthand. That was a good thing, too. If you wanted to erase a file named Hackaday, for example, you had to type: ERASE Hackaday AUT$PROF.

Styles

PROFS messages were short and were essentially ephemeral chat messages. Of course, because of the block-mode terminals, you could only get messages after you sent something to the mainframe, or you were idle in a menu. A note was different. Notes were what we could call e-mail. They went into your inbox, and you could file them in “logs”, which were similar to folders.

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Is That Ancient Reel Of PLA Any Good?

When it comes to knowledge there are things you know as facts because you have experienced them yourself or had them verified by a reputable source, and there are things that you know because they are common knowledge but unverified. The former are facts, such as that a 100mm cube of water contains a litre of the stuff, while the latter are received opinions, such as the belief among Americans that British people have poor dental care. The first is a verifiable fact, while the second is subjective.

In our line there are similar received opinions, and one of them is that you shouldn’t print with old 3D printing filament because it will ruin the quality of your print. This is one I can now verify for myself, because I was recently given a part roll of blue PLA from a hackerspace, that’s over a decade old. It’s not been stored in a special environment, instead it’s survived a run of dodgy hackerspace premises with all the heat and humidity that’s normal in a slightly damp country. How will it print?

It Ain’t Stringy

In the first instance, looking at the filament, it looks like any other filament. No fading of the colour, no cracking, if I didn’t know its age it could have been opened within the last few weeks. It loads into the printer, a Prusa Mini, fine, it’s not brittle, and I’m ready to print a Benchy.

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Ask Hackaday: How Do You Detect Hidden Cameras?

The BBC recently published an exposé revealing that some Chinese subscription sites charge for access to their network of hundreds of hidden cameras in hotel rooms. Of course, this is presumably without the consent of the hotel management and probably isn’t specifically a problem in China. After all, cameras can now be very tiny, so it is extremely easy to rent a hotel room or a vacation rental and bug it. This is illegal, China has laws against spy cameras, and hotels are required to check for them, the BBC notes. However, there is a problem: At least one camera found didn’t show up on conventional camera detectors. So we wanted to ask you, Hackaday: How do you detect hidden cameras?

How it Works

Commercial detectors typically use one of two techniques. It is easy to scan for RF signals, and if the camera is emitting WiFi or another frequency you expect cameras to use, that works. But it also misses plenty. A camera might be hardwired, for example. Or store data on an SD card for later. If you have a camera that transmits on a strange frequency, you won’t find it. Or you could hide the camera near something else that transmits. So if your scanner shows a lot of RF around a WiFi router, you won’t be able to figure out that it is actually the router and a small camera.

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The Weird Propeller That Offers Improved Agility On The Water

When it comes to seaborne propulsion, one simple layout has largely dominated over all others. You pair some kind of engine with some kind of basic propeller at the back of the ship, and then you throw on a rudder to handle the steering. This lets you push the ship forward, left, and right, and stopping is just a matter of turning the engine off and waiting… or reversing thrust if you’re really eager to slow down.

This basic system works for a grand majority of vessels out on the water. However, there is a more advanced design that offers not only forward propulsion, but also steering, all in the one package. It may look strange, but the Voith Schneider propeller offers some interesting benefits to watercraft looking for an edge in maneuverability.

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Big Heat Pumps Are Doing Big Things

The heat pump has become a common fixture in many parts of modern life. We now have reverse-cycle air conditioning, heat pump hot water systems, and even heat pump dryers. These home appliances have all been marketed as upgrades over simpler technologies from the past, and offer improved efficiency and performance for a somewhat-higher purchase price.

Heat pumps aren’t just for the home, though. They’re becoming an increasingly important part of major public works projects, as utility providers try to do ever more with ever less energy in an attempt to save the planet. These days, heat pumps are getting bigger, and will be doing ever grander things in years to come. Continue reading “Big Heat Pumps Are Doing Big Things”