Collective Pitch Thrust Vectoring On A RC Plane

November 15, 2013 by 59 Comments

The RC plane shown above is hovering in that position. And that’s about the least impressive thing it can do. This is the power of Collective Pitch Thrust Vectoring… on a plane.

So what exactly is Collective Pitch Thrust Vectoring anyway? Put simply, it’s like strapping a helicopter rotor to the front of a plane. We think the basic mechanism behind this is called a Swashplate (as found on a helicopter rotor), which allows for thrust vectoring, meaning the propeller blades can actually change their pitch cyclically, while still spinning at high speeds! This is what allows helicopters to do crazy tricks like barrel rolls.

A normal RC plane can only increase or decrease thrust with the speed of the engine. But with this, the thrust can be changed cyclically as the blades spin allowing for thrust vectoring (advanced steering). Couple that with some huge control surfaces and wing stabilizers and that means some seriously crazy aerodynamic feats.

Watch the video after the break, it’s amazing.

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Cloning The Trinket For A USB Volume Knob

November 14, 2013 by 16 Comments

A while back, [Rupert] wrote a blog post on using V-USB with the very small, 8-pin ATtiny85. Since then, the space of dev boards for 8-pin micros with USB has exploded, the most recent being Adafruit’s Trinket. [Rupert] liked what he saw with the Trinket bootloader and decided to clone the circuit into a useful package. Thus was born an awesome looking USB volume knob complete with a heavy aluminum knob, rotary encoder, and RGB LED strip.

[Rupert] got his V-USB/ATtiny85/rotary encoder circuit working, and at the expense of a ‘mute’ control, also added an awesome looking RGB LED ring powered by Adafruit’s Neopixels. The PCB [Rupert] fabbed is pretty well suited for being manufactured one-sided. If you’ve ever wanted an awesome volume knob for your computer, all the files are available form [Rupert]’s blog.

Just as an aside, [Rupert] has been working on getting the Trinket bootloader working on the ATtiny84, a very similar microcontroller to the ’85, but with eight analog pins. It’s a neat device that I’ve made a small V-USB breakout board for, but like [Rupert], I’m stuck on porting the bootloader. If anyone has the Trinket/Gemma firmware running on an ATtiny84, send that in. We’ll put it up.

Long-distance High Frequency APRS Tracking Using The FreeTrak63

November 14, 2013 by 21 Comments

FT63_857_etrex

If you dabble in the ham radio hobby we’re sure you’ve heard of GPS position monitoring or tracking using APRS packet data commonly transmitting over the VHF ham band and FM modulated. One of the issues you’ll face using this common method is range limitations of VHF. [Mike Berg] a.k.a [N0QBH ] tipped us off to his latest project to greatly increase the range of a standalone APRS system utilizing the HF bands on single-sideband (SSB).

There are some unique challenges transmitting packet data using SSB over HF bands.  High Frequency APRS has been around for decades utilizing FSK AX.25 packet transmissions at 300 baud, but it was quite susceptible to noise and propagation aberrations. More recently PSK-31 at the slower 31 baud speed helped alleviate many of these issues. [Mike] utilized the somewhat updated APRS with PSK-63 and the “APRS Messenger” program to overcome these challenges. [Mike’s] hardware solution consists of a PIC 16F690 micro which is coded to receive data from a GPS receiver, convert it into PSK-63 and then transmit on 30 meters over an attached HF radio. A second receiving station or stations at great distances can pick up and decode the transmission using the “APRS Messenger” program connected to the receiving radio over the computer’s soundcard. The program can then forward the tracking information, if good, to tracking websites like FindU.com and APRS.FI.

You can build your own FreeTrak63 by downloading [Mike’s] parts list, assembly code, HEX file, manual and schematic. The PCB is available on OSH Park if you don’t want to make your own or wire point-to-point. Let’s not forget to mention how hackable this hardware is, being really just an eight bit DAC, micro, serial in and radio out. One could reprogram this hardware to do other modulation schemes like AX.25 packet or MFSK16, the sky’s the limit. If short-distance on VHF with existing Internet linked receiver networks using an Arduino compatible platform is more to your taste, then checkout the Trackuino open source APRS Tracker.

Commodore 64 Power Glove Is So Bad

November 14, 2013 by 11 Comments

The Nintendo Power Glove was terrible. Really, really terrible. Thanks to modern components, though, it’s possible to recreate the Power Glove experience in a way that doesn’t suck so much. That’s what [Leif] did with his motion sensing glove for the Commodore 64.

Instead of rolling his own IMU and putting it in a glove, [Leif] is using SonicWear SoMo, a glove originally designed to generate MIDI data for performance pieces. Inside this glove is a 9 DOF gyro/accelerometer/magnetometer, uC, battery, and XBee that can be easily reprogrammed to do something a little more (or less) useful than simply sending MIDI notes and commands.

[Leif] reprogrammed the XBees to use I/O line passing instead of sending serial data, and connected the recieving XBee to the C64 joystick port through a very simple circuit with a hex inverter.

All the code to turn a SonicWear glove into a C64 controller is available on the Github, and there’s a neat demo video of [Leif] demoing his glove at the VCF Midwest late last month.

Human Powered Hydrofoil, The Wingbike!

November 14, 2013 by 22 Comments

[Steven] has been working for the past year on a very cool pedal powered hydrofoil, which he calls the Wingbike.

We’ve seen plenty of trampofoils before, which are hydrofoils that can convert a human bouncing up and down… to horizontal movement. There have even been some pedal powered versions before, but its a rather tricky mechanism to get just right.

[Steven] has built his Wingbike almost entirely out of carbon fiber, and it only weighs 10kg.The biggest problem is balance, as you’re about 1.5M above the foils. If you lean too much, you fall. If you slow down too much, you sink. The current model he is working on has fairly large foils, which does help a bit with the balance, but that also increases the amount of energy required to propel it. He plans on creating new designs with much smaller and faster foils in the future.

Unfortunately, the water is getting quite cold in the Netherlands, so he’s going to spend the rest of the winter months optimizing the bike from a design perspective. Stick around after the break to see his latest successful test video!

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Fail Of The Week: Automatic Baby Rocker

November 14, 2013 by 40 Comments

fotw-baby-bouncer

The art of hacking requires you to straddle many different types of engineering. In this case, it looks like [Dan] could use a little bit of brain-storming on how to get this doubly-failed project back on track. Do go easy on him as he wasn’t the one that submitted the write-up for this week’s Fail.

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A DIY NFC Tag

November 14, 2013 by 10 Comments

[Nicholas] built a simple NFC tag using an ATtiny84 microcontroller, four resistors, three capacitors, a diode, and an antenna. It implements ISO 14443-3, a standard for identification cards, and can communicate with the NFC chip sets found in most new smartphones.

This standard uses on-off keying for communication, which makes the hardware slightly more complex than the AVR RFID tag that we saw a few years back. The antenna and a variable capacitor form an LC circuit tuned at 13.56 MHz, which is the carrier frequency for the protocol. The diode acts as an envelope detector, letting the microcontroller recover the signal.

It may not be fully compliant with the standard, but [Nicolas] successfully tested out the device with his Lumia 620 phone. The firmware is available on Google Code so you can program your own tag data into main.c, build the firmware, and send some NFC packets. You can also check out a demo of the device after the break.

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