Single Molecule Detects Light

Everything is getting smaller all the time. Computers used to take rooms, then desks, and now they fit in your pocket or on your wrist. Researchers that investigate light sensors have known that individual diarylethene molecules can exist in two states: one where it conducts electricity and one where it doesn’t. A visible photon causes the molecule to be electrically open and ultraviolet causes it to close. But there’s a problem.

light600Placing electrodes on the molecule interferes with the process. Depending on the kind of electrode, the switch will get stuck in the on or off position. Researchers at Peking University in Beijing determined that placing some buffering material between the molecule and the electrodes would reduce the interference enough to maintain correct operation. What’s more the switches remain operable for a year, which is unusually long for this kind of construct.

Using chemical vapor deposition and electron beam lithography, the team produced over 40 working single molecule switches. These devices could be useful in optical computing and other applications. Future work will include developing multilevel switches comprised of multiple molecules.

If you want something more macroscopic, you might try using an LED to sense light. A switch is fine, but sometimes you want to generate a signal.

150,000 Members Strong, Hackaday.io Flies Past Another Milestone

We’re growing so fast that soon your mom will be on Hackaday.io. That’s fine, everyone who loves hardware is welcome. 150,000 members have made Hackaday.io a home for their creativity — looking for inspiration in the work of others, sharing successes and temporary failures, and building their dream team to take on amazing new challenges. There is no place in the world that can come close to matching the Open Hardware ecosystem that is Hackaday.io.

What is in that one number, 150k? It is a monumental chunk of a much bigger picture: the thriving Hackaday ecosystem that spans from staking down your own workshop full of projects and skills, to following the editorial pulse of hardware used in new and creative ways. Looking over the last twelve months on all of the Hackaday sites we’ve seen about 18.5 Million visitors and registered nearly 85 Million views. Hackaday is not a passive community. We all have an insatiable hunger to delve into the next big trick, and to celebrate the accomplishments that made it happen.

Want to find a new and unique way to use the tech you find most interesting? Your leap forward needs input to pollinate the idea. Hackaday has a critical mass of hackers, designers, and engineers waiting with excitement to hear and help out in exploring and expanding the frontier. These interaction are what has packed Hackaday.io with interesting people. Most would say: I came for a specific hack or to see what a particular hacker was up to, but then I felt at home and decided to stick around and share what I’ve spent way to much time doing (but I wouldn’t have it any other way).

As we continue to knock down one membership milestone after another I want to thank you all for being involved, for valuing the free and open sharing of information and ideas, and for sharing your own time and talent. You are what moves this community of hardware hackers to dizzying heights of excellence and awesome.

This is all too good to be a secret. Talk to your hardware-loving friends, colleagues, family, and acquaintances and invite them to Hackaday.io if they’re not already with us.

FAA Finalizes Rules For Drones, UAS, and Model Aircraft

The FAA and DOT have finalized their rules for small Unmanned Aircraft Systems (UAS, or drones), and clarified rules for model aircraft. This is the end of a long process the FAA undertook last year that has included a registry system for model aircraft, and input from members of UAS and model aircraft industry including the Academy of Model Aeronautics and 3D Robotics.

Model Aircraft

Since the FAA began drafting the rules for unmanned aircraft systems, it has been necessary to point out the distinction between a UAS and a model aircraft. Thanks to the amazing advances in battery, brushless motor, and flight controller technology over the past decade, the line between a drone and a model aircraft has been fuzzed, and onboard video systems and FPV flying have only blurred the distinction.

The distinction between a UAS and model aircraft  is an important one. Thanks to the FAA Reauthorization Act of 2012, the FAA, “may not promulgate any rule or regulation regarding a model aircraft” under certain conditions. These conditions include aircraft flown strictly for hobby or recreational use, operated in accordance with a community-based set of safety guidelines (read: the safety guidelines set by the Academy of Model Aeronautics), weighs less than 55 pounds, gives way to manned aircraft, and notifies the operator of an airport when flown within five miles of a control tower.

Despite laws enacted by congress, the FAA saw it necessary to create rules and regulations for model aircraft weighing less than 55 pounds, and operated in accordance with a community-based set of safety guidelines. The FAA’s drone registration system doesn’t make sense, and there is at least one pending court case objecting to these rules.

The FAA’s final rules for UAS, drones, and model airplanes change nothing from the regulations made over the past year. If your drone weighs more than 250 grams, you must register it. For model aircraft, and unmanned aircraft systems conducting ‘hobbyist operations’, nothing has changed.

Unmanned Aerial Systems

The finalized rule introduced today concerns only unmanned aircraft systems weighing less than 55 pounds conducting non-hobbyist operations. The person flying the drone must be at least 16 years old and hold a remote pilot certificate with a small UAS rating. This remote pilot certificate may be obtained by passing an aeronautical knowledge test, or by holding a non-student Part 61 pilot certificate (the kind you would get if you’d like to fly a Cessna on the weekends)

What this means

Under the new regulations, nothing for model aircraft has changed. The guys flying foam board planes will still have to deal with a registration system of questionable legality.

For professional drone pilots – those taking aerial pictures, farmers, or pilots contracting their services out to real estate agents – the situation has vastly improved. A pilot’s license is no longer needed for these operations, and these aircraft may be operated in class G airspace without restriction. Drone use for commercial purposes is now possible without a pilot’s license. This is huge for many industries.

These rules do not cover autonomous flight. This is, by far, the greatest shortcoming of the new regulations. The most interesting applications of drones and unmanned aircraft is autonomous flight. With autonomous drones, farmers could monitor their fields. Amazon could deliver beer to your backyard. There are no regulations regarding autonomous flight from the FAA, and any business plans that hinge on pilot-less aircraft will be unrealized in the near term.

DJI Phantoms are now ‘drones’

This is a quick aside, but I must point out the FAA press release was written by someone with one of two possible attributes. Either the author of this press release paid zero attention to detail, or the FAA has a desire to call all unmanned aircraft systems ‘drones’.

The use of the word ‘drone’ in the model aircraft community has been contentious, with quadcopter enthusiasts making a plain distinction between a DJI Phantom and a Predator drone. Drones, some say, have the negative connotation of firing hellfire missiles into wedding parties and killing American citizens in foreign lands without due process, violating the 5th amendment. Others have classified ‘drones’ as having autonomous capability.

This linguistic puzzle has now been solved by the FAA. In several places in this press release, the FAA equates ‘unmanned aircraft systems’ with drones, and even invents the phrase, ‘unmanned aircraft drone’. Language is not defined by commenters on fringe tech blogs, it is defined by common parlance. Now the definition of ‘drone’ is settled: it is an unmanned, non-autonomous, remote-controlled flying machine not flown for hobby or recreational use.

Espressif Releases ESP8266-Killer!

It’s no secret that we love the ESP8266 chip, and the community of hackers that have contributed to making it useful. We often joke about this or that new WiFi-enabler being an ESP8266 killer, but so far none have stepped up. Here we go again!

Espressif has released a chip that’s going to be an ESP8266 killer, and no, it’s not the ESP32. The ESP8285 went into mass production in March, and should start to appear in the usual outlets fairly soon.

What makes it an ESP8266 killer? It’s an ESP8266, but with the flash memory onboard. Nothing more, but also nothing less. What does this mean? Tiny, tiny designs are possible. And, if the street price ends up being right, there’s no reason you wouldn’t opt for built-in flash. (Unless you were planning on doing some ROM hacking.)

Continue reading “Espressif Releases ESP8266-Killer!”

FCC to Investigate Raised RF Noise Floor

If you stand outside on a clear night, can you see the Milky Way? If you live too close to a conurbation the chances are all you’ll see are a few of the brighter stars, the full picture is only seen by those who live in isolated places. The problem is light pollution, scattered light from street lighting and other sources hiding the stars.

The view of the Milky Way is a good analogy for the state of the radio spectrum. If you turn on a radio receiver and tune to a spot between stations, you’ll find a huge amount more noise in areas of human habitation than you will if you do the same thing in the middle of the countryside. The RF noise emitted by a significant amount of cheaper modern electronics is blanketing the airwaves and is in danger of rendering some frequencies unusable.

Can these logos really be trusted? By Moppet65535 (Own work) [CC BY-SA 3.0], via Wikimedia Commons
Can these logos really be trusted? By Moppet65535 (Own work) [CC BY-SA 3.0], via Wikimedia Commons
If you have ever designed a piece of electronics to comply with regulations for sale you might now point out that the requirements for RF interference imposed by codes from the FCC, CE mark etc. are very stringent, and therefore this should not be a significant problem. The unfortunate truth is though that a huge amount of equipment is finding its way into the hands of consumers which may bear an FCC logo or a CE mark but which has plainly had its bill-of-materials cost cut to the point at which its compliance with those rules is only notional. Next to the computer on which this is being written for example is a digital TV box from a well-known online retailer which has all the appropriate marks, but blankets tens of megahertz of spectrum with RF when it is in operation. It’s not faulty but badly designed, and if you pause to imagine hundreds or thousands of such devices across your city you may begin to see the scale of the problem.

This situation has prompted the FCC Technological Advisory Council to investigate any changes to the radio noise floor to determine the scale of the problem. To this end they have posted a public notice (PDF) in which they have invited interested parties to respond with any evidence they may have.

We hope that quantifying the scale of the RF noise problem will result in some action to reduce its ill-effects. It is also to be hoped though that the response will not be an ever-tighter set of regulations but greater enforcement of those that already exist. It has become too easy to make, import, or sell equipment made with scant regard to RF emissions, and simply making the requirements tougher for those designers who make the effort to comply will not change anything.

This is the first time we’ve raised the problem of the ever-rising radio noise floor here at Hackaday. We have covered a possible solution though, if stray RF is really getting to you perhaps you’d like to move to the National Radio Quiet Zone.

[via Southgate amateur radio news]

1000 CPUs on a Chip

Often, CPUs that work together operate on SIMD (Single Instruction Multiple Data) or MISD (Multiple Instruction Single Data), part of Flynn’s taxonomy. For example, your video card probably has the ability to apply a single operation (an instruction) to lots of pixels simultaneously (multiple data). Researchers at the University of California–Davis recently constructed a single chip with 1,000 independently programmable processors onboard. The device is energy efficient and can compute up to 1.78 trillion instructions per second.

The KiloCore chip (not to be confused with the 2006 Rapport chip of the same name) has 621 million transistors and uses special techniques to be energy efficient, an important design feature when dealing with so many CPUs. Each processor operates at 1.78 GHz or less and can shut itself down when not needed. The team reports that even when computing 115 billion instructions per second, the device only consumes about 700 milliwatts.

Unlike some multicore designs that use a shared memory area to communicate between processors, the KiloCore allows processors to directly communicate. If you are just a diehard Arduino user, maybe you could scale up this design. Or, if you want to make use of the unused power in your video card under Linux, you can always try to bring KGPU up to date.

Graphene Optical Boom Emits Light with No Diode

When a supersonic aircraft goes faster than the speed of sound, it produces a shockwave or sonic boom. MIT researchers have found a similar optical effect in graphene that causes an optical boom and could provide a new way to convert electricity into light.

The light emission occurs due to two odd properties of graphene: first, light gets trapped on the surface of graphene, effectively slowing it down. In addition, electrons pass through at very high speeds. Interestingly, the speeds are nearly the same–that is, electrons and trapped light travel at almost the same speed. The researchers found a way to make the electrons move faster than the speed of light (in the graphene) and thus created Cerenkov emissions. Because of the structure of graphene, the resulting light is intense and tightly focused.

The researchers speculate that this technique could be important in building graphene-based optical chips. We’ve talked about mixed graphene and semiconductor chips before. Graphene is pretty exotic stuff. It can even fold itself.