Do you need a well-equipped lab to measure the size of an atom (German, machine translation)? According to [stoppi], no. You need sunflower oil, some bear moss spores, and a bit of gasoline. You’ll also need some common things like a syringe, a baking sheet, and a jar. You can see the whole process in the video below. The measurement isn’t really for a specific atom, but it is an average for a lipid molecule, which is still impressive.
You essentially measure the diameter of an oil drop spread over water. Since the oil is mostly oleic acid, the height of the layer is known as 167 atoms. After that, it is some simple measurements and math to get the height and find the average atom height.
In Pirates of the Caribbean, Captain Jack Sparrow has an enchanted compass that points to what the holder wants most in life. The Pizza Compass created by [Joe Grand] is basically the same thing, except it’s powered by a Particle Boron instead of a voodoo spell. Though depending on who’s holding the thing, we imagine they’d even point in the same direction.
[Joe] was tasked by Wired to design and produce the Pizza Compass in three weeks, a process which was documented in the video below. Being the Badgelife luminary that he is, the final product looks far more attractive than it has any business being. In addition to the Particle Boron that slots in on the back of the handheld PCB, there’s a GlobalTop PA6H GPS module, a LSM303DLHC compass, and eight NeoPixels that correspond to the points on the silkscreen compass.
Using the device is simple, just press the button and then walk around trying to keep the top-most LED lit. Behind the scenes, the Boron is pulling down the coordinates of the closest pizza place as reported by Google’s API, and comparing that to the user’s current GPS location. In practice that means the Pizza Compass isn’t concerned with nuances like streets or buildings, so its up to the user to figure out how best to stay on the desired heading. So rather than just following some turn-by-turn directions, there’s some proper navigation involved if you want that fresh slice.
If you don’t like pizza, you could reprogram the compass to point to whatever quest-worthy resource you wish. As explained at the end of the video, [Joe] wanted this to be an open source project so it could easily be adapted for different tasks by the community. Though honestly, it’s pretty weird if you don’t like pizza.
With many of the achievements of the Space Race now more than half a century behind us, it’s no wonder that we’re steadily losing the men who rode the rockets of the Mercury, Gemini, and Apollo programs into space. They were all very much in their primes at the time, but no matter what you’ve accomplished in life, even if it includes a trip to the Moon, time eventually catches up to you.
Still, it was quite a shock to learn today that astronaut Michael Collins passed away today at the age of 90. Collins made his trip to the Moon aboard Apollo 11, the mission which would see his crewmates Neil Armstrong and Edwin “Buzz” Aldrin descend to the surface in the Lunar Module Eagle and take the historic first steps on its surface in July of 1969.
Winners have just been announced for Hackaday’s Earth Day Challenge. We were on the lookout for projects that raise awareness of environmental issues and are happy to celebrate three top winners. Each have won a $200 shopping spree from Digi-Key who sponsored this contest.
Pictured above is the Open Flow Meter by [Eben]. The build includes sensors that are submerged into a river or stream to gauge the speed at which the water is moving. It uses a commodity plumbing flow volume sensor to help reduce costs, adding an Arduino and touch screen for reading the sensors and providing a UI to the user.
High-altitude balloons are used for air quality and weather sensing. To make those sensor packages more reusable, [Hadji Yohan] has been working on a parachute recovery system that automatically returns to a set GPS point. It’s a parafoil with auto-pilot!
Power harvesting is a fascinating and tricky game. To help ease the transition away from batteries, [Jasper Sikken] developed a solar harvesting module that charges a Lithium Ion Capacitor (LIC) from a very small solar panel. Based around a 100 uF 30 F capacitor, it uses an AEM10941 energy harvesting chip which includes Maximum Power Point Tracking (MPPT) to utilize the solar panel as efficiently as possible. The fully charged module can output regulated 2.2 V and is aimed at distributed sensor packages that can be run without any battery at all.
Combined with today’s massive flat panel displays, a nice surround sound system can provide an extremely immersive environment for watching movies or gaming. But a stumbling block many run into is speaker placement. The front speakers generally just go on either side of the TV, but finding a spot for the rear speakers that’s both visually and acoustically pleasing can be tricky.
Which is why [Peter Waldraff] decided to take a rather unconventional approach and hide his rear surround sound speakers in a pair of functioning table lamps. This not only looks better than leaving the speakers out, but raises them up off the floor and into a better listening position. The whole thing looks very sleek thanks to some clever wiring, to the point that you’d never suspect they were anything other than ordinary lamps.
The trick here is the wooden box located at the apex of the three copper pipes that make up the body of the lamp. [Peter] mounted rows of LEDs to the sides of the box that can be controlled with a switch on the bottom, which provides light in the absence of a traditional light bulb. The unmodified speaker goes inside the box, and connects to the audio wires that were run up one of the pipes.
In the base, the speaker and power wires are bundled together so it appears to be one cable. Since running the power and audio wires together like this could potentially have resulted in an audible hum, [Peter] only ran 12 VDC up through the lamp to the LEDs and used an external “wall wart” transformer. For convenience, he also put a USB charging port in the center of the base.
[Lucas] over at Cranktown City on YouTube has been very busy lately, but despite current appearances, his latest project is not a welder. Rather, he built a very clever gas mixer for filling his homemade CO2 laser tubes, which only looks like a welding machine. (Video, embedded below.)
We’ve been following [Lucas] on his journey to build a laser cutter from scratch — really from scratch, as he built his own laser tube rather than rely on something off-the-shelf. Getting the right mix of gas to fill the tube has been a bit of a pain, though, since he was using a party balloon to collect carbon dioxide, helium, and nitrogen at measuring the diameter of the ballon after each addition to determine the volumetric ratio of each. His attempt at automating the process centers around a so-called AirShim, which is basically a flat inflatable bag made of sturdy material that’s used by contractors to pry, wedge, lift, and shim using air pressure.
[Lucas]’ first idea was to measure the volume of gas in the bag using displacement of water and some photosensors, but that proved both impractical and unnecessary. It turned out to be far easier to sense when the bag is filled with a simple microswitch; each filling yields a fixed volume of gas, making it easy to figure out how much of each gas has been dispensed. An Arduino controls the pump, which is a reclaimed fridge compressor, monitors the limit switch and controls the solenoid valves, and calculates the volume of gas dispensed.
Judging by the video below, the mixer works pretty well, and we’re impressed by its simplicity. We’d never seriously thought about building our own laser tube before, but seeing [Lucas] have at it makes it seem quite approachable. We’re looking forward to watching his laser project come together.
When computers were the sort of thing you ordered from a catalog and soldered together in your garage, swap meets were an invaluable way of exchanging not just hardware and software, but information. As computers became more mainstream and readily available, the social aspect of these events started to take center stage. Once online retail started really picking up steam, it was clear the age of the so-called “computer show” was coming to a close. Why wait months to sell your old hardware at the next swap when you could put it on eBay from the comfort of your own home?
Of course, like-minded computer users never stopped getting together to exchange ideas. They just called these meets something different. By the 2000s, the vestigial remnants of old school computer swap meets could be found in the vendor rooms of hacker cons. The Vintage Computer Festival (VCF) maintained a small consignment area where attendees could unload their surplus gear, but it wasn’t the real draw of the event. Attendees came for the workshops, the talks, and the chance to hang out with people who were passionate about the same things they were.
Then came COVID-19. For more than a year we’ve been forced to cancel major events, suspend local meetups, and in general, avoid one another. Some of the conventions were revamped and presented virtually, and a few of them actually ended up providing a unique and enjoyable experience, but it still wasn’t the same. If you could really capture the heart and soul of these events with a video stream and a chat room, we would’ve done it already.
But this past weekend, the folks behind VCF East tried something a little different. As indoor gatherings are still strongly discouraged by New Jersey’s stringent COVID restrictions, they decided to hold a computer swap meet in the large parking lot adjacent to the InfoAge Science and History Museum. There were no formal talks or presentations, but you could at least get within speaking distance of like-minded folks again in an environment were everyone felt comfortable.