Flywheel Stores Energy To Power An Airplane – Eventually

Question: Can a flywheel store enough energy to power an airplane? Answer: Yes it can, for certain values of “flywheel” and “airplane.”

About the only person we can think of who would even attempt to build a flywheel-powered airplane is [Tom Stanton]. He’s a great one for off-the-wall ideas that often pay off, like his Coandă effect hovercraft, as well as for ideas that never got far off the ground, or suddenly met it again. For most of the video below, it seems like his flywheel-powered plane is destined to stay firmly in the last category, and indeed, the idea of a massive flywheel taking flight seems counterintuitive. But [Tom] reminds us that since the kinetic energy stored by a flywheel increases as the square of angular velocity, how fast it’s turning is more important than how massive it is. The composite carbon fiber and aluminum flywheel is geared to the propeller of a minimal airplane through 3D-printed bevel gears, and is spun up with an external BLDC motor.

Sadly, the plane never made it very far, no matter how much weight was trimmed. But [Tom] was able to snatch victory from the jaws of defeat by making the propeller the flywheel – he printed a ring connecting the blades of the prop and devised a freewheel clutch to couple it to the motor. The flywheel prop stored enough energy to complete a few respectable flights, as well as suffer a few satisfyingly spectacular disintegrations.

As always, hats off to [Tom] for not being bashful about sharing his failures so we can all learn, and for the persistence to make his ideas take flight.

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Mars 2020 Rover: Curiosity’s Hi-Tech Twin Is Strapped For Science; Includes A Flying Drone

While Mars may be significantly behind its sunward neighbor in terms of the number of motor vehicles crawling over its surface, it seems like we’re doing our best to close that gap. Over the last 23 years, humans have sent four successful rovers to the surface of the Red Planet, from the tiny Sojourner to the Volkswagen-sized Curiosity. These vehicles have all carved their six-wheeled tracks into the Martian dust, probing the soil and the atmosphere and taking pictures galore, all of which contribute mightily to our understanding of our (sometimes) nearest planetary neighbor.

You’d think then that sending still more rovers to Mars would yield diminishing returns, but it turns out there’s still plenty of science to do, especially if the dream of sending humans there to explore and perhaps live is to come true. And so the fleet of Martian rovers will be joined by two new vehicles over the next year or so, lead by the Mars 2020 program’s yet-to-be-named rover. Here’s a look at the next Martian buggy, and how it’s built for the job it’s intended to do.

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Emulating A Bluetooth Keyboard With The ESP32

Most people associate the ESP family of microcontrollers with WiFi, which makes sense as they’ve become the solution of choice for getting your project online quickly and easily. But while the WiFi capability might be the star of the show, the ESP32 also comes equipped with Bluetooth; we just don’t see people using it nearly as often. If you’re looking to get started using Bluetooth on the ESP32, then this simple wireless macro keypad from [Brian Lough] would be a great way to get started.

From a hardware standpoint, this project is incredibly straightforward. All you need to do is connect a membrane keypad up to the GPIO pins on the ESP32. Adding in a battery is a nice touch, and you probably would want to put it into a enclosure of some sort, but as a proof of concept it doesn’t get much easier than this. In this case [Brian] is using the TinyPICO board, but your personal ESP32 variant of choice will work just as well.

The rest of the project is all software, which [Brian] walks us through in the video after the break. There’s a preexisting library for Bluetooth Human Interface Device (HID) emulation on the ESP32, but it needs to be manually installed in the Arduino IDE. From there, he demonstrates how you can build up a functioning keyboard, including tricks such as sending multiple virtual keys at once.

In the past we’ve seen the ESP32 used to create a Bluetooth game controller, but the ability to emulate a keyboard obviously offers quite a bit more flexibility. With a practical demonstration of how easy as it is to turn this low-cost microcontroller into a wireless input device, hopefully we’ll start seeing more projects that utilize the capability.

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Star Wars Themed Laser Badge: All That Is Missing Is The Pew Pew Sound Effect

In the quest to advance the art of the electronic badge, the boundaries of what is possible to manufacture in small quantities are continually tested. Full-colour PCBs, injection moulding, custom keyboards, and other wow factor techniques have all been tried, leading to some extremely impressive creations. With all this innovation then it’s sometimes easy to forget that clever design and a really good idea can produce an exceptional badge with far more mundane materials.

The 10th InCTF cybersecurity contest held at Amrita, Kerala, India, had a Star Wars themed badge designed by Team bi0s for the event. It takes the form of a Millennium Falcon-shaped PCB, with a NodeMCU ESP8266 board mounted on it, a shift register, small OLED display, and the usual array of buttons and LEDs. The fun doesn’t stop there though, because it also packs a light-dependent resistor and a laser pointer diode that forms part of one of its games. Power for this ensemble comes courtesy of a set of AA cells on its underside.

They took a novel approach to the badge’s firmware, with a range of different firmwares for different functions instead of all functions contained in one. These could be loaded through means of a web-based OTA updater. Aside from a firmware for serial exploits there was an Asteroids game, a Conway’s Game Of Life, and for us the star of the show: a Millennium Cannon laser-tag game using that laser. With this, attendees could “shoot” others’ LDRs, with three “hits” putting their opponent’s badge out of action for a couple of minutes.

Unusually this badge is a through-hole design as a soldering teaching aid, but its aesthetics do not suffer for that. We like its design and we especially like the laser game, we look forward to whatever next Team bi0s produce in the way of badges.

This isn’t the first badge packing a laser we’ve seen, at last year’s Def Con there was a laser synth badge. No laser tag battles though.