Kritik sah

Seeing airplanes fly in formation is an exciting experience at something like an air show, where demonstrations of a pilot’s skill and aircraft technology are on full display. But there are other reasons for aircraft to fly in formation as well. [Peter] has been exploring the idea that formation flight can also improve efficiency, and has been looking specifically at things like formation flight of UAVs or drones with this flight planning algorithm. Aircraft flying in formation create vortices around the wing tips, which cause drag. However, another aircraft flying through those vortices will experience less drag and more efficient flight. This is the reason birds instinctively fly in formation as well. By planning paths for drones which will leave from different locations, meet up at some point to fly in a more efficient formation, and then split up close to their destinations, a significant amount of energy can potentially be saved. [Peter] is using a modified version of the RRT*...

Join us on Wednesday, June 28 at noon Pacific for the Desktop EDM Hack Chat with Cooper Zurad ! Whether you know it or not, chances are pretty good you’ve run into the results of electrical discharge machining at some point. EDM is the go-to machining method for so many applications, from making complex injection molding tooling to putting impossibly small holes into hardened steel, EDM gets the jobs that make traditional machining techniques weep. At its heart, EDM is really simple; it’s just making sparks to selectively erode metal. In practice, though, it’s way more complicated than that. There’s the CNC aspect to control the cutting tool, the dielectric to cool things and flush away the swarf, and the precision control of the electric discharge. It’s all just complicated and expensive enough that it’s hard to find anyone doing EDM on the hobbyist level. Hard, but not impossible. Desktop EDM is doable, and to help us understand the challenges involved we’ve invited Cooper Zurad...

Starlink has been making tremendous progress towards providing world-wide access to broadband Internet access, but there are a number of downsides to satellite-based internet such as the cluttering of low-Earth orbit, high expense, and moodiness of CEO. There are some alternatives if standard Internet access isn’t available, and one of the more ambitious is providing Internet access by balloon. Project Loon is perhaps the most famous of these (although now defunct), but it’s also possible to skip the middleman and build your own high-altitude balloon capable of connection speeds of 500 Kbps . [Stephen] has been working on this project for a few months and while it doesn’t support a full Internet connection, the downlink on the high altitude balloon is fast enough to send high-resolution images in near-real-time. This is thanks to a Raspberry Pi Zero on board the balloon that is paired with an STM32 board which handles the radio communication on a RF4463 transceiver module. The STM32 ...

Back in the last century, especially in the ’40s to the ’60s, one of the major home decor trends was to install various home appliances, like the television or stereo, into its own piece of furniture. These were usually bulky, awkward, and incredibly heavy. And, since real life inspires art, most of the futuristic sci-fi technology we saw in movies and TV of the time was similarly conspicuous and physical. Not so with modern technology, though, where the trend now is to hide it out of the way and forget it exists. But [dermbrian] wanted some of his modern technology to have some of the mid-century visibility aesthetic so he made some modifications to his Amazon Echo . The Echo itself remains largely unmodified, other than placing it inside a much larger cookie tin with some supporting electronics. For that, [dermbrian] found a relay board with a built-in microphone which switches the relay off when it detects sound so that when the Echo is activated, the sound from its speaker activa...

Interfacing biological and electrical systems has traditionally been done with metal electrodes, but something flexible can be more biocompatible. One possible option is 3D-printed bioelectric hydrogels . Electrically conductive hydrogels based on conducting polymers have mechanical, electrical, and chemical stability properties in a fully organic package that makes them more biocompatible than other systems using metals, ionic salts, or carbon nanomaterials. Researchers have now found a way to formulate bi-continuous conducting polymer hydrogels (BC-CPH) that are a phase-separated system that can be used in a variety of manufacturing techniques including 3D printing. To make the BC-CPH, a PEDOT:PSS electrical phase and a hydrophilic polyurethane mechanical phase are mixed with an ethanol/water solvent. Since the phase separation occurs in the ink before deposition, when the solvent is evaporated, the two phases remain continuous and interspersed, allowing for high mechanical stabil...

Is it really a dystopian future if the robots are radio-controlled? That’s what came to mind reading this article on a police robot out of Singapore , complete with a breathless headline invoking Black Mirror , which is now apparently the standard by which all dystopias are to be judged. Granted, the episode with the robo-dogs was pretty terrifying, but it seems like the Singapore Police Force has a way to go before getting to that level. The bot, which has been fielded at Changi Airport after extensive testing and seems to be completely remote-controlled, is little more than a beefy telepresence robot. At 5.5 feet (1.7 meters) tall, the bot isn’t terribly imposing, although it apparently has a mast that can be jacked up another couple of feet, plus there are lights, sirens, and speakers that can get the message across. Plus cameras, of course; there are always cameras. The idea is to provide extra eyes to supplement foot patrols, plus the potential to cordon off an incident until mea...

Over the last five to ten years, smart watches have become fairly ubiquitous, with the Apple Watch being among the most prominent of them. Not everyone wants or needs all of the capabilities of these devices, though; plenty are still opting for simpler devices which only have a few functions built into them. [Josh] has been working on one of these devices but takes a major design cue from their smart counterparts with the addition of gesture controls for the watch built into the wristband instead of relying on a more traditional button interface. The watch hosts most of the functionality of a non-smart digital watch, with a timer, alarms, and a stop watch built-in. To change the time or access any of these functions, a combination of resistive and capacitive touch sensors are built into the wristband near the watch face. The combination of sensors aims to use the benefits of either type of sensor, with the capacitive sensors being used for precision and gesture recognition and the r...