No, despite what it might look like, this isn’t some early Halloween project. The creepy creation before you is actually a tongue-in-cheek “robot” created by the prolific [Nick Bild], a topical statement about companies asking their remote workers to come back into the office now that COVID-19 restrictions are being lifted. Why commute every day when this ultra realistic avatar can sit in for you?
OK, so maybe it’s not the most impressive humanoid creation to ever grace the pages of Hackaday. But if you’re looking to spin up a simple telepresence system, you could do worse than browsing through the Python source code [Nick] has provided. Using a Raspberry Pi 4, a webcam, and a microphone, his client-server architecture combines everything the bot sees and hears into a simple page that can be remotely accessed with a web browser.
Naturally this work from home (WFH) bot wouldn’t be much good if it was just a one-way street, so [Nick] has also added a loudspeaker that replays whatever he says on the client side. To prevent a feedback loop, his software includes a function that toggles which direction the audio stream goes in by passing the appropriate commands to the bot over SSH; a neat trick to keep in mind for your own, less nightmarish, creations.
[Rostislav Persion] wrote a simple Morse Code decoder to run on his Arduino and display the text on an LCD shield. This is probably the simplest decoder possible, and thus its logic is pretty straightforward to follow. Simplicity comes at a price — changing the speed requires changing constants in the code. We would like to see this hooked up to a proper Morse code key, and see how fast [Rostislav] could drive it before it conks out.
In an earlier era of Morse code decoders, one tough part was dealing with the idiosyncrasies of each sender. Every operator’s style, or “fist”, has subtle variations in the timings of the dots, dashes, and the pauses between these elements, the letters, and the words. In fact, trained operators can recognize each other because of this, much like we can often recognize who is speaking on the phone just by hearing their voice. The other difficulty these decoders faced was detecting the signal in low signal-to-noise ratio environments — pulling the signal out of the noise.
A Morse decoder built today is more likely to be used to decode machine-generated signals, for example, debugging information or telemetry. This would more than likely be sent at fixed, known speeds over directly connected links with very high S/N ratios (a wire, perhaps). In these situations, a simple decoder like [Rostislav]’s is completely sufficient.
We wrote about a couple of Morse code algorithms back in 2014, the MorseDetector and the Magic Morse algorithm. While Morse code operators usually rank their skills by speed — the faster the better — this Morse code project for very low power transmitters turns that notion on its head by using speeds more suitably measured in minutes per word (77 MPW for that project). Have you used Morse code in any of your projects before? Let us know in the comments below.
Farming has been undergoing quite a revolution in the past few years. Since World War 2, most industrial farming has relied on synthetic fertilizer, large machinery, and huge farms with single crops. Now there is a growing number of successful farmers bucking that trend with small farms growing many crops and using natural methods of fertilizing that don’t require as much industry. Of course even with these types of farms, some machinery is still nice to have, so this farmer has been developing an open-source automated farming robot.
The robot is known as Acorn and is the project of [taylor] who farms in California. The platform is powered by an 800 watt solar array feeding a set of supercapacitors for energy storage. It uses mountain bike wheels and tires fitted with electric hub motors which give it four wheel drive and four wheel steering to make it capable even in muddy fields. The farming tools, as well as any computer vision and automation hardware, can be housed under the solar panels. This prototype uses an Nvidia Jetson module to handle the heavy lifting of machine learning and automation, with a Raspberry Pi to handle the basic operation of the robot, and can navigate itself around a farm using highly precise GPS units.
While the robot’s development is currently ongoing, [taylor] hopes to develop a community that will build their own versions and help develop the platform. Farming improvements like this are certainly needed as more and more farmers shift from unsustainable monocultures to more ecologically friendly methods involving multiple simultaneous crops, carbon sequestration, and off-season cover crops. It’s certainly a long row to hoe but plenty of people are already plowing ahead.
Got an nRF52 or nRF51 device you need to flash? Got an ESP32 laying around collecting dust? If so, then firmware hacking extraordinaire [Aaron Christophel] has the open source code you need. His new project allows the affordable WiFi-enabled microcontroller to read and write to the internal flash of Nordic nRF52 series chips via their SWD interface. As long as you’ve got some jumper wires and a web browser, you’re good to go.
In the first video below [Aaron] demonstrates the technique with the PineTime smartwatch, but the process will be more or less the same regardless of what your target device is. Just connect the CLK and DIO lines to pins GPIO 21 and GPIO 19 of the ESP32, point your web browser to its address on the local network, and you’ll be presented with a straightforward user interface for reading and writing the chip’s flash.
As demonstrated in the second video, with a few more wires and a MOSFET, the ESP32 firmware is also able to perform a power glitch exploit on the chip that will allow you to read the contents of its flash even if the APPROTECT feature has been enabled. [Aaron] isn’t taking any credit for this technique though, pointing instead to the research performed by [LimitedResults] to explain the nuts and bolts of the attack.
It seems like the world is ready for a true 3D display. We’ve seen them in sci-fi for decades now, with the ability to view a scene from any angle and inspect it up close. They’ve remained elusive, but that might just be changing thanks to this open-source persistence-of-vision volumetric display.
If the VVD, as it has been named by its creator [Madaeon], looks somewhat familiar, perhaps it’s because editor-in-chief [Mike Szczys] ran into it back in 2019 at Maker Faire Rome. It looks like it has progressed quite a bit since then, but the basic idea is still the same. A thin, flexible membrane, which is stretched across a frame, is attached to articulated arms. The membrane can move up and down rapidly, fast enough that a 1,000-fps high-speed camera is needed to see it move. That allows you to see the magic in action; a digital light processor (DLP) module projects slices of a 3D image onto the sheet, sending the correct image out for each vertical position of the membrane. Carefully coordinating the images creates the POV illusion of a solid image floating in space, which can be observed from any angle, requires no special glasses, and can even be viewed by groups.
With displays like this, we’re used to issuing the caveat that “it no doubt looks better in person”, but we have to say in the GIFs and videos included the VVD looks pretty darn good. We think this is a natural for inclusion in the 2021 Hackaday Prize, and we’re pleased to see that it made it to the semi-finals of the “Rethink Displays” round.
Airships. Slow, difficult to land, and highly flammable when they’re full of hydrogen. These days, they’re considered more of a historical curiosity rather than a useful method of transport.
Hybrid Air Vehicles are a UK-based startup working to create a modern take on the airship concept. The goal is to create cleaner air transport for short-hop routes, while also solving many of the issues with the airship concept with a drastic redesign from the ground up. Their vehicle that will do all this goes by the name of Airlander 10. But is it enough to bring airships back to the skies?
A Hybrid Technology
The Airlander 10 is not a lighter-than-air craft like traditional airships. Instead, the vehicle uses the buoyancy from its helium envelope to create only 60-80% of its lift. The rest of the left is generated aerodynamically by air passing over the eliptical shape of the airship’s body. This lift can also be further augmented by two diesel-powered ducted fans on the sides of the airship, which can pivot to assist with takeoff and landing. Two further fixed ducted fans on the rear provide the primary propulsion for the craft.
The hybrid approach brings several benefits over the traditional airship model. Chief among them is that as the Airlander 10 is heavier than air, it need not vent helium throughout flight to avoid becoming positively buoyant as fuel burns off, nor does it need to vent helium to land. However, it still maintains the capability to loiter for incredibly long periods in the sky as it needs to burn very little fuel to stay aloft. Reportedly, it is capable of five days when manned, and even longer durations if operated in an unmanned configuration. Using helium for lift instead of solely relying on engine thrust and wings means that it is much more fuel efficient than traditional fixed-wing airliners. The company’s own estimates suggest the Airlander 10 could slash emissions on short-haul air routes by up to 90%. The gentle take-off and landing characteristics also mean the vehicle doesn’t require traditional airport facilities, making it possible to operate more easily in remote areas, on grass, sand, or even water. Continue reading “Could Airships Make A Comeback With New Hybrid Designs?”→
Putting the last piece of a project together and finally finishing it up is a satisfying feeling. When the last piece of a puzzle like that is a literal puzzle, though, it’s even better. [Nadieh] has been working on this jigsaw puzzle that displays a fireworks-like effect whenever a piece is placed correctly, using a lot of familiar electronics and some unique, well-polished design.
The puzzle is a hexagonal shape and based on a hexagonally symmetric spirograph, with the puzzle board placed into an enclosure which houses all of the electronics. Each puzzle piece has a piece of copper embedded in a unique location so when it is placed on the board, the device can tell if it was placed properly or not. If it was, an array of color LEDs mounted beneath a translucent diffuser creates a lighting effect that branches across the entire board like an explosion. The large number of pieces requires a multiplexer for the microcontroller, an ATtiny3216.
This project came out of a FabAcademy, so the documentation is incredibly thorough. In fact, everything on this project is open sourced and available on the project page from the code to the files required for cutting out the puzzle pieces and the enclosure. It’s an impressive build with a polish we would expect from a commercial product, and reminds us of an electrified jigsaw puzzle we saw in a previous build.