Shannon Morrisey's Posts (42)

Atomo is Like LEGO for Electronics


Cool Atomo prototyping kits from HK.

"There are a number modules, including I/O boards, network expansion boards and even power supplies for bigger projects. For example, the project below has four I/O adapters and a power supply all connected to a Raspberry Pi. This means you can do some really interesting things with robotics and even hydroponics with the package the size of a hunk of cheese.

The kit costs $39 for early birds and should ship in June. You’ll be able to buy more packages and mix and match them as necessary."

From TechCrunch

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Very cool application using the excellent HackRF platform demoed at Defcon.

From HackADay:

What do you get when you combine one of the best (and certainly one of the best for the price) software defined radios with the user interface of a 10-year-old iPod? The HackRF PortaPack, developed by [Jared Boone], and demonstrated at DEFCON last weekend.

[Jared] is one of the original developers for the HackRF, a 10MHz to 6GHz software defined radio that can also transmit in half duplex. Since the development of the HackRF has (somewhat) wrapped up, [Jared] has been working on the PortaPack, an add-on for the HackRF that turns it into a portable, ARM Cortex M4-powered software defined radio. No, it’s not as powerful as a full computer running GNU Radio, but it does have the capability to listen in on a surprising amount of radio signals.

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Very cool project using RasPi as a transmitter for controlling RC toys.  The dev employed an impressive brute-force method [script + webcam] to identify command codes.

From HackADay:  

An interesting trick you can do with a a fast CPU and a GPIO pin mapped directly to memory is an FM transmitter. Just toggle a pin on and off fast enough, and you have a crude and kludgy transmitter. [Brandon] saw a few builds that turned a Raspberry Pi into an FM radio transmitter and realized a lot of toy remote control cars use a frequency in the same range a Pi can transmit at. It’s not much of a leap to realize the Pi can control these remote control cars using only a length of wire attached to a GPIO pin.

The original hack that turned a Pi GPIO pin into an FM transmitter mapped a GPIO pin to memory, cycled through that memory at about 100 MHz, and added a fractional divider to slightly adjust the frequency, turning it into an FM transmitter. Cheap RC cars usually listen for radio signals at 27 and 49 MHz. It doesn’t take much to realize commanding RC cars with a Pi is possible.

The only problem with this idea is that most RC cars use pulse modulation. For an RC transmitter to send the command for ‘forward’, a synchronization pulse is sent, then a series of pulses and pauses. The frequency doesn’t change at all, something the originally FM code doesn’t do. [Brandon] realized that if he just moved the frequency up to something the RC car wasn’t listening to, that would register as a zero.

All that was left was to figure out the command codes for his RC truck. For this, [Brandon] decided brute force would be the best option. Armed with a script and a webcam, he cycled through all possible combinations until the webcam detected a moving truck. Subtlety brilliant, if you ask us. Of course more complex commands required an oscilloscope, but now [Brandon] has a git full of all the code to control a cheap RC car with a Pi.

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DIY FPGA Reflow Oven


Cool Xmas Day project uses Papilio FPGA control

From HackADay:

"For Christmas, [Hamster]‘s wife gave him a mini-oven. Later that day, he tore it apart and built this FPGA controlled reflow oven.

We’ve seen plenty of reflow oven builds in the past. Most of those projects use a microcontroller to do closed loop control, sensing the temperature and toggling the heating element to hit a set point. This build uses the Papilio One FPGA development board as a controller. It implements a state machine that meets the reflow profile of the solder paste, ensuring SMD components are soldered properly.

The oven uses a MAX31855 to read temperature from a thermocouple. This device provides amplification, cold junction compensation, and analog to digital conversion which spits out the temperature over SPI. To control the heater, a 40A solid state relay is used.

The VHDL code that drives this oven is linked in the writeup, and has some interesting bits for those looking to experiment with FPGAs. It includes an SPI interface, display driver, and the temperature state machine logic."

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Has Flight Automation Gone Too Far?


Interesting read on the limits and human factors complicating flight automation.  I contend that all issues are solved with better sensors & processing ability/reliability.

From Things With Wings:

"As far back as 1980, renowned aviation human factors guru Earl Wiener (pictured sitting in the captain’s seat of the a Northwest Airlines Boeing 757 circa 1992) was asking the question on everyone’s mind after the tragic crash of Asiana Flight 214 in San Francisco earlier this month – Has automation gone too far?

Had he been around and of sound mind, Wiener would surely have weighed in.

However he passed away June 14 at the age of 80, the victim of a long bout with Parkinson’s disease. 

Along with his family, books and scholarly papers and a new generation of human factors professionals, Wiener left us with Wiener's Laws, 15 jewels of wisdom that will keep giving for decades to come because human nature, hence human error, is not changing all that rapidly. 

The laws were sent to me by former Wiener student and co-worker Asaf Degani, Ph.D., now a technical fellow at General Motors. “Some are funny and some are dead serious,” says Degani. 

I have no explanation of why Laws 1-16 are "intentionally left blank"...

Which one is your favorite? 


(Note: Nos. 1-16 intentionally left blank)

17. Every device creates its own opportunity for human error.

18. Exotic devices create exotic problems.

19. Digital devices tune out small errors while creating opportunities for large errors.

20. Complacency? Don’t worry about it.

21. In aviation, there is no problem so great or so complex that it cannot be blamed on the pilot.

22. There is no simple solution out there waiting to be discovered, so don’t waste your time searching for it.

23. Invention is the mother of necessity.

24. If at first you don’t succeed… try a new system or a different approach.

25. Some problems have no solution. If you encounter one of these, you can always convene a committee to revise some checklist.

26. In God we trust. Everything else must be brought into your scan.

27. It takes an airplane to bring out the worst in a pilot.

28. Any pilot who can be replaced by a computer should be.

29. Whenever you solve a problem you usually create one. You can only hope that the one you created is less critical than the one you eliminated.

30. You can never be too rich or too thin (Duchess of Windsor) or too careful what you put into a digital flight guidance system (Wiener).

31. Today’s nifty, voluntary system is tomorrow’s F.A.R.


Wiener in the early 1980s began researching what happens when humans and computers attempt to coexist on a flight deck. Though his “day job” was professor of management science at the University of Miami, Wiener is widely known for embedding in jump seats of his airline pilot subjects as part of research projects funded by the NASA Ames Research Center. Wiener would continue performing NASA human factors works for more than two decades. “Earl was an ongoing grantee,” says a NASA co-worker from that time. “He would publish a paper and 25 people would write their masters’ theses or doctoral dissertations on the topic.

In a 1980 paper he co-wrote with NASA’s Renwick Curry, “Flight-deck automation: promises and problems”, Wiener wrote, “It is highly questionable whether total system safety is always enhanced by allocating functions to automatic devices rather than human operators, and there is some reason to believe that flight-deck automation may have already passed its optimum point.” Compilations of scholarly papers by Wiener and his colleagues resulted in two key human factors books, one of which – Human Factors in Aviation – is still in publication today, albeit as a new edition with new editors.""

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The Rise of Winglets

Winglets%20Falcon%2050%20Spiroid.jpgNice brief article explains winglets & shows some new and unusual concepts

From Things With Wings - AvaitionWeek:


"Winglets all work in the same basic way, but they don't all look the same. In essence, winglets reduce drag by recovering some of the energy in the wingtip vortex. This provides an effective increase in wing aspect-ratio (span² divided by area - a measure of slenderness), and therefore a reduction in lift-induced drag, for a smaller increase in span, weight and profile drag compared with simply making the wing longer

Once rare, winglets have become commonplace, and over the years their design has evolved to make them more efficient and maximize the fuel savings they provide. Here are some examples of how winglets have changed - and how they could change in the future."


"A third recent patent, also assigned to Airbus (above, US patent 8,387,922), uses the winglet for more than just reducing wing drag. Actively controlled surfaces are added to the trailing edges of the winglets to introduce aerodynamic instabilities into the eddies shed by the wing. These instabilities would accelerate the dissipation of high-velocity wake vortices and allow aircraft to follow each other more closely. (in the diagram above the cylindrical object (20) at the bottom is a structural housing for the active-surface actuators)."

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Major Technology Patent Case Pending


A federal appeals court is about to review a case with broad implications for abstract technology patents. 

From BusinessInsider:

"Alice, based in Melbourne, Australia, and owned in part by National Australia Bank Ltd, holds a portfolio of patents, including four that cover a computerized system for exchanging financial obligations. The company argues that when an invention requires the use of a computer, even if it involves an abstract idea, "it's patentable if the computer plays a significant role in the invention.

Many technology and Internet companies worry that too many patents have been granted for simple ideas, hindering others from building innovations using those principles. They say this slows technology development, though other companies, including smaller developers and individuals, say inventors deserve legal protections for their innovations.
Google, Dell Inc and Facebook filed a friend-of-the-court brief criticizing the appeals panel's earlier decision.

They wrote that "bare-bones patents" like Alice's do not innovate enough on their own to deserve patent protection. "The real work comes later, when others undertake the innovative task of developing concrete applications," they wrote.

LinkedIn Corp, Twitter and others also submitted a friend-of-the-court brief, arguing against too much leniency in granting patents, though they did not pledge support for either side in the case.

International Business Machines Corp, on the other hand, filed a brief saying most software inventions qualify for patent protection. IBM, which has topped the list of U.S. patent recipients for 20 years, cautioned the court against creating a strict rule that would further limit protection, though it did not side with either party in the lawsuit."

more detailed & formal synopsis here hints at how out of their depth judges are when ruling on such technical issues

related hilarity over at Dangerous Prototypes

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UAV Civilian Market Roundtable


Interesting roundtable discussion among UAV 'experts' and opinion leaders

From The Engineer: 'The role of the pilot, or commander, or whatever the person overseeing the aircraft is called, is already covered by the existing regulations and the concept of equivalence, said Corbett. Although there are differences in how control is exercised, ‘the aircraft is still piloted, whether it’s by waggling a stick, or using point-and-click with a mouse and on-screen interface. The elements of “airmanship” have to be exactly the same as any other pilot occupying the same piece of airspace, because they will have to cope with the same conditions. Their training might be different, but the end result has to be the same.’

 In fact, Corbett said, the whole category of UAV is somewhat misleading. ‘There are four categories of aircraft: glider, balloon, airship and flying machine, and there are manned and unmanned versions of each,’ he said. ‘But if they’re going to operate in the same airspace, then UAVs shouldn’t be considered separately, as something tagged onto the side. They’re just another subset of the same categories.’

'...another consideration is the interest from potential commercial UAS users, and where their demands could pull the technology. Much of the demand is for vehicles which fly at or below 500m, where some of the technology developed in Astraea — sense-and-avoid, for example — might not need to be so complex, as there is little chance of colliding with other aircraft or trees at these altitudes.  ‘But the two ends [high- and low-altitude] will come together as the technology miniaturises,’ commented Dopping-Heppenstal. ‘We’ll see lessons from small-scale UAVs taken up by those developing larger aircraft...’

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Aircraft Design for Fail


Modern fault-tolerance design for aircraft does little to help when big parts start falling off. This study proposes a design approach / philosophy for keeping things aloft during broader system failure.

From PsysOrg: /
"For example, the group studied the plane’s operation during a maneuver called the “Dutch roll,” in which the plane rocks from side to side, its wingtips rolling in a figure-eight motion. The potentially dangerous motion is much more pronounced when a plane’s rudder is faulty, or one of its engines isn’t responding. Using their design approach, the group found that in such partially failed conditions, if the plane’s tail was larger, it could damp the motion, and steady the aircraft.

Of course, a plane’s shape can’t morph in midflight to accommodate an engine sputter or a rudder malfunction. To arrive at a plane’s final shape — a geometry that can withstand potential failures — de Weck and his researchers weighed the likelihood of each partial failure, using that data to inform their decisions on how to change the plane’s shape in a way that would address the likeliest failures.

De Weck says that while the group’s focus on failure represents a completely new approach to design, there is also a psychological element with which engineers may have to grapple.“Many engineers are perfectionists, so deliberately designing something that’s not going to be fully functional is hard,” de Weck says. “But we’re showing that by acknowledging imperfection, you can actually make the system better.”

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A University of Colorado Asst. Professor is transitioning his GoJett Supersonic UAV project into a business.

From University of Colorado News:

"The UAV is intended to shape the next generation of flight experimentation… Its thrust capacity makes the aircraft capable of reaching Mach 1.4, which is slightly faster than the speed of sound. Starkey says that regardless of the speed reached by the UAV, the aircraft will break the world record for speed in its weight class.

Its compact airframe is about 5 feet wide and 6 feet long. The aircraft costs between $50,000 and $100,000 -- a relatively small price tag in a field that can advance only through testing, which sometimes means equipment loss.

Starkey’s technology -- three years in the making at CU-Boulder -- is transitioning into a business venture through his weeks-old Starkey Aerospace Corp., called Starcor for short. The company was incubated by eSpace, which is a CU-affiliated nonprofit organization that supports entrepreneurial space companies. Starkey’s UAV already has garnered interest from the U.S. Army, Navy, Defense Advanced Research Projects Agency and NASA. The acclaimed Aviation Week publication also has highlighted Starkey’s UAV.

Starkey says technology transfer is important because it parlays university research into real-life applications that advance societies and contribute to local and global economies."

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Industrial Robot Porn

I met some new industrial robots in the flesh at ATX West (Automation Technology Expo).  Nothing particularly groundbreaking here, but the speed and dexterity of the latest generation is remarkable (many were too fast for my phone's camera frame rate). There were a ton of these 4 and 6-axis delta robots (ones with 3 skinny steel arms). Also saw the very cool Festo adaptive gripper (first clip holding Cadbury egg) and some giant 3D printers.  Like a kid in a candy store.

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Fascinating NYU experiment reveals surprising data on fluid-dynamics for top-heavy airborne structures.  

From ScienceMag (video) via Wired Science

"Think that floating pyramids are more metaphysics than physics? Think again. Results just in from an experiment that levitated open-bottomed paper pyramids on gusts of air reveal a curious phenomenon: When it comes to drifting through the air, top-heavy designs are more stable than bottom-heavy ones. The finding may lead to robots that fly not like insects or birds but like jellyfish.

The researchers placed hollow paper pyramids inside the cylinder. The objects were about 1 to 5 centimeters high and were made of tissue paper or letter paper on carbon fiber supports, like tiny homemade kites. Physicist Bin Liu led the experiments, attaching a beadlike weight to a post running down the center of the pyramid and changing the height of the bead to give the object a different center of mass. Common sense says that the pyramid should be most stable when the bead is at the bottom of the post, like ballast in the hold of a ship. But when the team released the pyramids over the subwoofer, the opposite was true: the bottom-heavy pyramids were likely to flip over and fall, whereas the top-heavy ones remained upright and continued to hover (see first video), the group reports in an upcoming issue of Physical Review Letters.

Zhang's team suggests that flapping pyramid or cone robots could combine stability and maneuverability. They would quickly right themselves if they leaned further than 30° in any direction, but within 30°, they should move freely."

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Congress Passes UAV Bill


The flying robot equality bill aims to end prejudice inside heavily segregated FAA airspace, among other things.

From The Washington Post:

"The FAA is also required under the bill to provide military, commercial and privately-owned drones with expanded access to U.S. airspace currently reserved for manned aircraft by Sept. 30, 2015. That means permitting unmanned drones controlled by remote operators on the ground to fly in the same airspace as airliners, cargo planes, business jets and private aircraft.

Currently, the FAA restricts drone use primarily to segregated blocks of military airspace, border patrols and about 300 public agencies and their private partners. Those public agencies are mainly restricted to flying small unmanned aircraft at low altitudes away from airports and urban centers."

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ArduinoCommander is a sweet new Android app for controlling Arduino with a Bluetooth shield. 

From Android Market:

"Control your Arduino board from your Android device via Bluetooth using WYSIWYG interface.

- discover and connect to Arduino board with Bluetooth shield (like Sparkfun bluetooth modems:
- display board firmware version, name and Firmata protocol version
- set pin mode (analog/digital input/output, pwm)
- get/set pin values
- read messages from the board (Firmata String Sysex message)
- beautiful WYSIWYG interface with 320x480, 480x800, 480x854, 1024x600 and 1280x800(?) screens support"

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Kickstarter Drone is a Hoax


After receiving much attention over the past few days, the aforementioned Eye3 Drone project on Kickstarter has been officially pulled on account of photoshop shenanigans and overall shadiness.

From IEEE Automation Blog:

"At first glance, the eye3 drone seemed like an incredible deal. For US $2500, you could get yourself a beefy hexacopter capable of lifting over 6.8 kilograms (15 pounds) with an included autopilot that would take all of the hassle and stress out of flying the UAV...

People on the Internet, being people on the Internet, did some digging and found out several things. First, the pictures of the kit on Kickstarter are just pictures of this kit (from with the attribution photoshopped out. Also, the founders of eye3 allegedly owe a bunch of people money (or a product) on another project."

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How Fast Can You Fly Without Crashing?


A professor at MIT developed an equation to determine the fastest theoretical air-speed for obstacle avoidance.

From Science Blog:  "Emilio Frazzoli, an associate professor of aeronautics and astronautics at MIT, says knowing how fast to fly can help engineers program unmanned aerial vehicles (UAVs) to fly at high speeds through cluttered environments such as forests and urban canyons.

Most UAVs today fly at relatively slow speeds, particularly if navigating around obstacles. That’s mainly by design: Engineers program a drone to fly just fast enough to be able to stop within the field of view of its sensors.

Frazzoli and PhD student Sertac Karaman developed mathematical models of various forest densities, calculating the maximum speed possible in each obstacle-filled environment.

The team’s work establishes a theoretical speed limit for any given obstacle-filled environment. For UAVs, this means that no matter how good robots get at sensing and reacting to their environments, there will always be a maximum speed they will need to observe to ensure survival."

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Universal GSM Remote Control module


TiDiGino is a new open source Arduino-based (ATmega2560) GSM remote control module.  From open-electronics via dangerous prototypes

"The remote can be operated by commands sent by SMS, but you can also control it via the serial port (connected to USB converter).
Each command is followed by a response (via SMS) directly to the sender, but the answer may be disabled. In addition there is an alarm function, as the automatic sending of SMS or voice calls, based on conditions on each of the two inputs.
The circuit can also be used as a gate control, calling the SIM in the TiDiGino: the system recognize the calling number and if this number is stored the relay will switch on. In the DTMF mode, the remote control can be controlled by a multi-frequency telephone tone.
In addition, the circuit can operate as a thermostat, running an air conditioning system."

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Android Circuit Editor/Simulator App


By far the coolest phone / tablet app I've come across. EveryCircuit is a simple SPICE circuit design tool with a slick touch interface, shows voltage and current animations and more.  This is no doubt the look and feel of circuit design tools for the future. Also could be a fun, easy way to learn or teach circuit technology. 


From Android Market
"Features: + Animations of voltage waveforms and current flows+ Analog control knob adjusts circuit parameters+ Automatic wire routing+ Seamless DC and transient simulation+ Single play/pause button controls simulation+ Saving and loading of circuit schematic+ Mobile simulation engine built from ground-up+ Intuitive user interface+ No AdsComponents:+ Sources, signal generators+ Resistors, capacitors, inductors+ Diodes, Zener diodes, light emitting diodes (LED)+ MOS transistors (MOSFET)+ Bipolar junction transistors (BJT)+ Ideal operational amplifier (opamp)+ Digital logic gates, AND, OR, NOT, NAND, NOR, XOR, XNOR.   Coming Soon: + Oscilloscope+ More components"




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