Geckos are amazing creatures, with the ability to walk on and stick to all manner of surfaces. If you’ve ever woken up to see lizards on your ceiling, you’re already familiar with their capabilities. The mechanisms behind this have been an area of much research in recent times, and [The Thought Emporium] decided to try and recreate the effect himself (Youtube video, embedded below).
The way geckos stick to surfaces is through the use of nano-scale hairs on their feet. These hairs dramatically increase the surface area of contact between the gecko and the surface in question. This allows the usually-small intermolecular forces to stack up and keep the gecko adhered.
Several teams have managed to create synthetic substances that recreate this ability; indeed we’ve featured some here before. In this case, experimentation started with an attempt to generate the requisite nanostructures by casting RTV silicone on a microporous filter. This was unsuccessful, with the hairs on the surface of the material created being too sparse and at random angles. The next stage involved attempting to use a tattoo gun, needles, and finally sharpened tungsten wires to pattern wax, which could then have silicone cast onto it to pick up the geometry. This too was unsuccessful, as it wasn’t possible to generate tiny enough features to generate the effect.
The final experiment involved casting silicone upon a 1000 line per millimeter diffraction grating. This generated tiny ridges on the surface of the silicone, and greatly improved its sticking ability. While the ridges generated aren’t as capable as gecko feet or professionally-produced films, they do have an impressive weight holding ability. A small section of the silicone was able to hold over 20 pounds for an extended period in testing.
It’s a great example of how to do seemingly complicated science with materials that can be easily acquired for the home workshop. We’d love to see just how strong a gecko tape could be produced with more work done on this method. Video after the break.
Continue reading “Easy DIY Gecko Tape”
Knowing in what absolute direction your robot is pointed can be crucial, and expensive systems like those used by NASA on Mars are capable of calculating this six-dimensional heading vector to within around one degree RMS, but they are fairly expensive. If you want similar accuracy on a hacker budget, this paper shows you how to do it using cheap MEMS sensors, an off-the-shelf motion co-processor IC, and the right calibration method.
The latest article to be published in our own peer-reviewed Hackaday Journal is Limits of Absolute Heading Accuracy Using Inexpensive MEMS Sensors (PDF). In this paper, Gregory Tomasch and Kris Winer take a close look at the heading accuracy that can be obtained using several algorithms coupled with two different MEMS sensor sets. Their work shows that when properly used, inexpensive sensors can produce results on par with much more costly systems. This is a great paper that illustrates the practical contributions our community can make to technology, and we’re proud to publish it in the Journal.
Continue reading “Do You Know Where Your Drone Is Headed? HJWYDK Article Explores Limits Of MEMS Sensors”
Aerogels have changed how a lot of high tech equipment is insulated. Resembling frozen smoke, the gel is lightweight and has extremely low thermal conductivity. However there’s always a downside, traditional aerogel material is brittle. Any attempt to compress it beyond 20% of its original size will change the material. Researchers at UCLA and eight other universities around the world have found a new form of ceramic aerogel that can compress down to 5% of its original size and still recover. It is also lighter and able to withstand extreme temperature cycles compared to conventional material. The full paper is behind a paywall, but you can view the abstract.
Traditional aerogel is more likely to fracture when exposed to high temperatures or repeated temperature swings, but the new material is more robust. Made from boron nitride, the atoms have a hexagonal pattern which makes it stronger.
Continue reading “Ceramic Aerogel Meets Stretch Goals”
Every year at Superconference, Editor-in-Chief Mike Szczys gets the chance to talk about what we think are the biggest, most important themes in the Hackaday universe. This year’s talk was about science and technology, and more importantly who gets to be involved in building the future. Spoiler: all of us! Hackaday has always stood for the ideal that you, yes you, should be taking stuff apart, improving it, and finding innovative ways to use, make, and improve. To steal one of Mike’s lines: “Hackaday is an engine of engagement in engineering fields.”
Continue reading “Supercon 2018: Mike Szczys And The State Of The Hackaday”
In the early 1990s, I was lucky enough to get some time on a 60 MeV linear accelerator as part of an undergraduate lab course. Having had this experience, I can feel for the scientists at CERN who have had to make do with their current 13 TeV accelerator, which only manages energies some 200,000 times larger. So, I read with great interest when they announced the publication of the initial design concept for the Future Circular Collider (FCC), which promises collisions nearly an order of magnitude more energetic. The plan, which has been in the works since 2014, includes three proposals for accelerators which would succeed CERN’s current big iron, the LHC.
Want to know what’s on the horizon in high-energy physics?
Continue reading “The Future Circular Collider: Can It Unlock Mysteries Of The Universe?”
There are a whole bunch of high school science experiments out there that are useful for teaching students the basics of biology, physics, and chemistry. One of the classics is the lemon battery. [iqless] decided to have a play with the idea, and whipped up a little something for his students.
The basic lemon battery is remarkably simple. Lemon juice provides the electrolyte, while copper and and zinc act as electrodes. This battery won’t have a hope of charging your Tesla, but you might get enough juice to light an LED or small bulb (pun intended).
[iqless] considered jamming electrodes directly into lemons to be rather unsophisticated. Instead, an electrolyte tray was 3D printed. The tray can be filled with lemon juice (either hand-squeezed or straight from a bottle) and the tray has fixtures to hold copper pennies and zinc-plated machine screws to act as the electrodes. The tray allows several cells to be constructed and connected in series or parallel, giving yet further teaching opportunities.
It’s a fun twist on a classroom staple, and we think there are great possibilities here for further experimentation with alternative electrolytes and electrode materials. We’d also love to see a grown-up version with a large cascade of cells in series for lemon-based high voltage experiments, but that might be too much to ask. There’s great scope for using modern maker techniques in classroom science – we’ve discussed variations on the egg drop before. Video after the break.
Continue reading “A Lemon Battery Via 3D Printing”
You’d be hard-pressed to walk down nearly any aisle of a modern food store without coming across something made of plastic. From jars of peanut butter to bottles of soda, along with the trays that hold cookies firmly in place to prevent breakage or let a meal go directly from freezer to microwave, food is often in very close contact with a plastic that is specifically engineered for the job: polyethylene terephthalate, or PET.
For makers of non-food objects, PET and more importantly its derivative, PETG, also happen to have excellent properties that make them the superior choice for 3D-printing filament for some applications. Here’s a look at the chemistry of polyester resins, and how just one slight change can turn a synthetic fiber into a rather useful 3D-printing filament.
Continue reading “Plastics: PETG”