On December 10th, 2017 we learned about

The invention and improvements that led to the modern roll of toilet paper

If you’re old enough to read these words, you’re probably at a stage in your life where you can take things like toilet paper for granted. Using your annual quota of 50 pounds of toilet paper per year may feel easy, but like any tool, it’s something you had to be taught to use and understand (as my four-year-old is now acutely aware of.) Beyond our acclimation to wiping ourselves with paper products, there’s been technological innovation in toilet paper as well, starting with the invention of paper itself.

Early years of paper hygiene products

Just a few hundred years after paper was invented in China, their revolutionary material for writing found its way into someone’s toilet. In 589 AD, the first account of using paper for personal hygiene was documented in Korea. By 1391, paper was being produced in China for the express purpose of wiping one’s rear. That paper came in awkwardly large sheets, around two- by three-feet overall, but at least had some perfume in it to make the experience more pleasant. It wasn’t an immediate world-wide hit though, partially because these tissues were intended for the emperor’s family only. Paper was still too precious for most people to dispose of after a single use.

This early start certainly didn’t put toilet paper, scented or unscented, into everyone’s bathroom. For many parts of the world, paper was scarce enough that it wasn’t even being used in books, much less in toilets. Instead, many folks made (or continue to make) due with a variety of options that many of us wouldn’t really associate with wiping. Throughout history, the list of bathroom tissue alternatives has included stones, sponges, clay, moss, shells, sticks, hands and corncobs.

Building a better toilet tissue

By the 17th century, paper products started making their way into the bathroom in the western world, but only after it arrived in the mailbox. Newspapers and magazines were repurposed as toilet paper in the American colonies, since paper was finally cheap enough to be disposable. Dedicated toilet paper was made available in 1857 by a one Joseph Gayetty, but it faced stiff competition in the form of the Sears Roebuck catalog. The latter was mailed out for free, and came with a hole punched in the corner, making it convenient to hang in one’s outhouse. This interest in convenience may have informed the next big innovations toilet paper technology, as in 1871 Seth Wheeler started selling perforated sheets in a role rather than a tissue-style box.

That doesn’t mean the story of toilet paper was settled in 1871 though. It wasn’t until 1935 that Northern Tissue offered “splinter free” paper with a process called linenizing, reminding us of how much bravery a trip to the lavatory once required. Two-ply tissue arrived in 1942, and colored paper was available in 1954. As important as all these improvements were, toilet paper’s place in public awareness was also being updated in this time period, since at one point the whole concept of wiping one’s self was deemed too inappropriate to even bring up, much less purchase in a public setting.

Selling toilet paper to an uncomfortable public

While Joseph Gayetty was proud enough of his medicated tissues to put his name on every one, other manufacturers were a bit more hesitant to brag about their products. Thomas Seymour, Edward Irvin and Clarence Wood Scott started producing rolled toilet paper, but sold it directly to hotels and drugstores, putting their clients’ names on them instead of their own. The Scott Paper Company didn’t really acknowledge their toilet paper production until 1896, over a decade after they started selling it. At the end of the 19th century, homes started being built with indoor plumbing, meaning older methods for hygiene, like corncobs, weren’t acceptable anymore. This gave toilet paper an opening in public discourse, since the product could be advertised for how well it broke apart in plumbing, avoiding too much detail about what it did directly for consumers themselves.

The final innovation on this front came from the Hoberg Paper Company in 1928. The company started selling their toilet tissues in “ladylike” packaging, since bragging about softness and feminine qualities would be easier than getting into the specifics of cleaning one’s nether-regions. When coupled with paper sold in four-packs, the branding was enormously successful, helping keep Charmin afloat through the Great Depression and beyond. They’ve had a number of major advertising campaigns since, but they’ve all been based around notions of soft, tactile enjoyment without getting too specific about where you’re supposed to actually feel that softness. Even though toilet paper use is growing worldwide, it’s still not something most of us (over age four) want to discuss in great detail.

Source: Who Invented Toilet Paper?, Toilet Paper History

On December 7th, 2017 we learned about

Robotic tractors will soon be adding more automation to building construction

Something people don’t tell you about parenthood is how much time you have to spend lurking around construction sites. Something about the preschool brain finds huge pieces of machinery rather mesmerizing, leading to mornings where a walk or bike ride has to be put on pause so you can watch just how cool excavators really are. Workers on job sites have been pretty welcoming as well, often answering questions or just sharing my kids’ appreciation for what a bulldozer can do. Some of this dynamic my change in the near future though, because a company called Built Robotics is looking to change the scheduling of construction, and maybe even get rid of some of the folks who currently control major machines.

Unmanned machinery

Right now, Built Robotics is starting small, working on turning a standard Bobcat skid loader into an autonomous robot. Ideally, the small tractor will be delivered to a site and given instructions about the size of the future building, at which point it will start scraping out a foundation pit on its own. It will navigate the space using a combination of GPS and LIDAR, the same laser systems employed by robotic vacuum cleaners to figure out the shape of your living room. It’s a bit trickier for these robotic tractors though, since if they’re doing their job, they’ll be constantly changing the shape of the space around them, which makes establishing navigational reference points a little more complicated.

Once all these technical challenges are smoothed over, a robotic tractor promises to do the same work as people, but in a more compact schedule since nobody would necessarily be limited to the schedules a human being finds comfortable. It would also remove some humans from the job site, meaning there would be fewer people at risk of injury, which is an attractive notion. Some of those people might still be needed to help manage the robotic tractors, but only if they’re up tackling a new set of specialties.

Effects of automation

From my four-year-old’s perspective, the coming wave of robotic tractors is kind of a mixed bag. On one hand, it’s a combination of tractors and robots, which is cool by definition, even if those tractors can’t also transform into humanoid warriors. On the other hand, if these tractors are somehow quiet enough to work all hours of the day without bothering the neighbors, construction will no longer be on a preschool-friendly schedule. The compressed building schedule will probably be appealing to everyone who wants to use the resulting building, but it’ll leave us much less time to stop and gawk.

Source: This Robot Tractor Is Ready To Disrupt Construction by Matt Simon, Wired

On November 28th, 2017 we learned about

Origami-inspired robots promise significant strength in a soft, squishy shell

I’ve made a few origami frogs in the past, and while they did successfully hop, I never appreciated how close I was to making a robot. The amount of potential and kinetic energy in the frog’s flexing legs seemed negligible, but apparently carefully controlled folding can not only trigger movement, but it can offer some considerable strength as well. While my little paper frogs weren’t about to do any heavy lifting, researchers from Harvard and MIT have found that lightweight, foldable materials can do a lot of work, even moving objects 1,000 times their own weight.

Air-powered contraction and expansion

The key to these folded robots is how they turn folded materials into veritable motors. A simple example uses a strip of stiff paper or plastic, folded in a basic accordion shape. That zig-zagging strip functions as a sort of “skeleton” for the machine, but it needs an outer covering to be activated. A simple plastic bag sealed around the folded strip is sufficient to act as the machine’s “muscles,” as long as that bag has a valve that can manipulate air flow. Sucking the air out of the valve with an air pump naturally causes the bag to contract, constricting around the folded paper. As the whole machine contracts, it’s strong enough to lift a weight many times its own mass. Letting air back into the bag allows the folded strip to expand again, lowering the weight in a controlled manner. In short, it’s a simple crane, powered by lightweight materials and a vacuum pump.

A folded strip is only the beginning though, as well-placed creases and joints in the inner skeleton can make for much more complicated articulation. One prototype was a four-pronged claw that can contract with enough strength to lift a tire. Another was a multi-jointed arm, ending in a flower-shaped gripper that can open and close as air is added or removed from the system. While they promise outsized strength, each design works with very simple, zig-zagged folds in the internal plastic structures, keeping them lightweight and very importantly, squishy.

Softer and safer

We have many machines that can lift a lot of weight, but the strength exhibited by these machines is quite noteworthy for something that’s soft and relatively safe. With no hard motors, actuators, joints or power sources, these machines can be used in places that harder robots wouldn’t be appropriate, like close to the human body. Since less than an ounce of foldable machine can lift over six pounds of weight, researchers think these gentle robots could be fit to human bodies, supporting or augmenting people who need help with certain tasks. They’d need to have a way to inflate and deflate the machine, but it would still be safer and more comfortable than carrying a huge set of gears, servos or hydraulic pistons.

At this point, researchers still haven’t made a jumping frog, unfortunately. The snap you get when releasing an origami frog is actually a bit speedy for these machines, as they can only move as fast as they’re inflated. An upcoming goal instead focuses on maximizing strength and articulation, as researchers aim to build a robotic elephant trunk. Since a trunk contains no hard bones but is incredibly mobile thanks to its 150,000 muscle fascicles, or muscle sections. It will likely require some carefully coordinated folding, but it would also prove that these inflation-based “muscles” will allow for very versatile machines in the near future.

Source: Artificial muscles give soft robots superpower, Phys.org

On November 14th, 2017 we learned about

The evolution of empty space in how we read and write

It’s a safe bet that you’re reading this text silently, because that’s how text works, right? You read the words presented, process their meaning in your mind, and then maybe relate them to others verbally or by sharing the text directly (hint hint.) At this point, I’m going to guess that you’re wondering why this is even being spelled out to you- this is how reading works, right? As it turns out, this concept of reading is relatively new. For the majority of human history, people had a very different relationship with words on a page, starting with all the parts that they didn’t even bother to transcribe in the first place.

Skipping vowels or spaces

While alphabets have existed for nearly 4000 years, not all languages recorded them like a modern English speaker is used to. Languages related to Aramaic, like Hebrew and Phoenician, had vowels but didn’t write them down. Instead, consonants were strung together, and readers just had to use context to put together what word was intended by the author. As difficult as that may sound, some modern languages, including Arabic, still use a writing system that skips writing vowels. European languages obviously did start incorporating vowels thanks to the ancient Greeks, although when they started writing them, they dropped some critical punctuation as a trade-off.

By the time The Iliad was written, Greeks had more or less given up on spaces between words, adopting a system now known as scriptio continua. The entire word was spelled out, but entiresentencesweremashedtogether. It seems like this would just convince all the Greeks to declare “too long, didn’t read,” and do an extent they did. This is because the purpose of writing at that time was primarily to record someone’s oral statements so that they could be stated for a new audience. Mashing words together without spaces made reading a bit more cumbersome, but that was fine when the point of a written scroll was read words aloud to other people. The reader could see what sounds to pronounce, and so plowing through an endless line of phonemes worked fine.

Adding spaces for accessibility

As human societies came in more and more contact with each other, scriptio continua started causing problems. For hundreds of years, the few people who could read throughout Europe were satisfied with this kind of writing, since most listeners were never going to see the text itself to even worry about it. However, in the ninth century, Irish scribes hit a snag, as the manuscripts they were copying were proving to be extremely difficult to parse. As native Celtic speakers, the scribes couldn’t simply “hear” the gaps in the words that speakers of Romance languages like Italian or French could, and so they started incorporating other cues in the writing to help make sense of things. They started with line breaks, giving each sentence it’s own line on a page. That was followed by spaces between words, with the Book of Mulling being the first volume to be transcribed in a way that wouldn’t immediately scare off a modern reader.

Adding spaces to a page did more than make sentences more intelligible. As the practice spread across Europe, it started to influence people’s relationship with writing. This new writing no longer put the emphasis on sounds and speech, allowing for the reader to become the primary audience instead of a performer. With that change in focus, making a page pleasing to the reader sparked new ideas in graphic design, since those efforts would help readers and writers alike. The printing press and subsequent accessibility of reading materials obviously cemented the idea of reading as something people could do by themselves, but the simple act of putting spaces between words was a key step towards making reading a goal unto itself, although it’s certainly not time to think that our relationship with the written word has been settled.

Trading space for more speed

The amount of writing in the world today is unmatched in history. More people are expected to read more than ever before, and huge amounts of that text is found on electronic devices that are starting to sever our relationship with the media it appears on. Modern graphic design loves white space more than ever, and many people would advise that the most accessible writing is lists of short phrases as opposed to “walls of text” that will scare readers away. However, as more writing appears on screens, there’s a chance that we could give up spacing in an entirely new way, displaying only one word at a time on your screen.

Instead of scanning your eyes across a sentence, text can be animated, with each word changing in the center of your screen so your eyes can focus on one physical location. It’s a significantly faster way to read, as moving your focus across a page or screen slows you down just a bit. As we consume more writing on daily basis, reading at 600 to 1000 words per minute may start to sound pretty attractive, as much as that would baffle the ancient Greeks.

Source: No Word Unspoken by Daniel Zalewski, Lingua Franca

On October 19th, 2017 we learned about

Frozen pee may be a practical reference point in our future search for life on Enceladus

In 2005, the Cassini spacecraft captured images of plumes of icy water erupting from Saturn’s moon, Enceladus. Subsequent flybys and sampling have suggested that this moon may be habitable by some form of life in its sub-surface ocean, thanks to geological heating. However, this is all inconclusive at this point, because Cassini wasn’t designed to tackle this kind of mission. Even when the spacecraft was flown through the moon’s icy geysers, it could only sample a limited portion of the ejected slush, since the probe could only detect one size of ice grain at a time. Now that Cassini has been crashed into Saturn, researchers are hoping to get another probe to Enceladus, but they need to make sure it’s ready for the job, and that means developing a better understanding of frozen water when it’s flushed into space.

In better tailor sensors for the icy ejecta of Enceladus, engineers would like experiment with, or at least observe, water as it flows into the cold vacuum of space. Of course, water is heavy and therefore expensive to get off the ground, plus astronauts value it as a way to stay, you know, alive. So rather than fly water up to space only to toss it out, it’s been proposed that we start paying closer attention to how wastewater from astronauts’ toilets as well as fuel cells, behaves when it’s vented from spaceships. Wastewater, or any water, spewed from a small metal tube wouldn’t be a perfect proxy for the vents of Enceladus, but it may be a starting point for measuring what kind if ice crystal distribution should be expected.

Previous work with purged pee

There’s also some precedent for these observations. In 1989, researchers used a telescope in Hawaii to watch as the space shuttle Discovery dumped water from its fuel cells. They couldn’t develop a full 3D model from these observations, but they could at least note that two sizes of ice grain formed. Bigger pieces of ice formed right out of the vent, while smaller grains, probably from recondensed water vapor, formed further away. The space shuttles also ejected liquid waste while on missions, although they made sure to keep the astronauts poop for later disposal back on Earth. Some of this vented liquid was found to form long icicles just outside the vents, suggesting another phenomenon that could be found on Enceladus.

While space shuttles dumped liquids more often, the International Space Station doesn’t quite provide the same opportunities to observe frozen pee. Pee isn’t sprayed into space as much anymore, partially due to the realization that frozen urine ejected from the Mir space station in the late 1980s had been slowly damaging the facility’s solar panels. Instead, most of the astronauts’ pee is cleaned and recycled into drinking water, leaving only the most concentrated, briny, urea to be purged into space. Astronauts’ poop doesn’t get tossed out either, but is instead packaged with other bundles of trash that are dropped into the natural incinerator that is the Earth’s atmosphere.

With these limitations, it’s not clear how much we’ll learn by watching astronaut’s waste water. At the very least, the stuff humans flush can at least provide a basic reference point for what to expect the next time we’re near Enceladus.

Source: Astronaut wee could show us how the plumes on Enceladus work by Leah Crane, New Scientist

On October 12th, 2017 we learned about

Materials and methods that can make a building a bit more fire-proof

With wildfires destroying over 3,500 structures across northern California in the last week, it’s understandable that my kids are feeling concerned about the safety of our own home. Aside from the smoke, we’re well out of harms way, but that hasn’t stopped some age-appropriate brainstorming about fire safety. Maybe force-fields would help? How about everyone using their garden hoses to spray the fires? Why can’t houses just be fire-proof?

Fire-proof, in the 3rd-grade understanding of the term, probably isn’t possible, but houses can be made to be very fire-resistant. Depending on the materials and design of a building, it may be able to withstand up to four hours of intense flames, and even then structural problems might come up before the whole thing actually burns. Basically, the key is to build in materials that can absorb and withstand heat while remaining chemically inert— ie., not actually combusting themselves. From that perspective, the wood frames that hold up so many American homes are sort of a terrible idea, as the wood will both burn and transmit heat to other parts of the structure. Moving away from the idea of a rustic log cabin, we should really all be living in homes made of concrete.

Preventing conflagration with concrete

Concrete frames and walls provide a number of advantages over wood. The limestone, clay and gypsum that go into concrete are very stable, and thus unlikely to react with oxygen and heat during a fire. Instead, a concrete slab can absorb a lot of heat, trapping some of it in internal pockets and pores. This can help isolate the heat from a fire, as well as insulate the building from unpleasant hot and cold temperatures in less dire circumstances. If you want to maximize the impact of your concrete walls, you probably want to install them as insulated concrete forms (ICFs), which are modular systems to further compartmentalize your concrete slabs, keeping the buildup of heat from a fire as isolated as possible.

If a building isn’t concrete, there are other options to up its fire-resistance. Bricks, having been created in kilns, hold up to heat quite well. In a fire, they can absorb heat without being damaged, with the point of failure usually being the mortar that holds a wall together. Gypsum board used in drywall can absorb a fair amount of heat without burning as well, with Type X gypsum boards being packed with calcium sulfate and water vapor inside. When exposed to fire, the water vapor can help suck up a lot of heat before the gypsum has to get cooked too much, all of which will hopefully provide time for the fire to be dealt with. On the outside of your building, common stucco usually has cement, sand and lime as ingredients, which again are inert enough to absorb heat without burning themselves.

Bad and best practices

Even with concrete or brick walls, many buildings still have weaknesses that can make them susceptible to fires. Vinyl siding and framing around windows melts pretty easily, exposing any wood framing underneath. Single pane windows that get broken allow both heat and oxygen to pass into or out of a burning building. If the source of flames is from an external wildfire, roofs are often a point of combustion. Loose shingles or semi-open tile work, can provide openings burning embers to get into a house’s attic. Overhangs are another place where fire-resistant materials are likely to be joined to more combustible wood, exposing the roof to danger even if the walls are otherwise unscathed.

So what should my kids’ theoretical fire-proof house look like then? Starting with the yard, no trees or brush should be too close to the house itself. Instead of a wooden deck, a stone or concrete patio would act as a firebreak, protecting the concrete walls. Tempered glass windows, or maybe glass bricks with an internal wire matrix to avoid cracking, would be further protected by roll-down metal fire doors that could deploy automatically in response to extreme heat. A steeply pitched roof would encourage burning embers to fall to the ground, rather than sitting and burning on the building. Internal walls would be brick or concrete, maybe with gypsum boards if you needed a softer material for some surfaces. It might start to feel a little bit like a fortress, as long as no lava (“Or asteroids!” “Or monsters!”) show up, it should be one of the cozier places to be after a wildfire.

Source: Why is concrete fire resistant? by Colleen Cancio, How Stuff Works

On October 4th, 2017 we learned about

Detailed data helps curtail conflict between forest and owl conservation

The forests of Northern California have presented a puzzle for conservationists. On one hand, there was a need to protect the dwindling spotted owl (Strix occidentalis) population, making sure they had enough trees in which to build their nests and lay their eggs. On the other hand, dry conditions from long-term droughts posed a large fire hazard for both the forest and human developments. To reduce the risk of large-scale fires, there was a push to thin forests by culling smaller trees, but this seemed to then threaten the owls’ nests. Fortunately, actual measurements were made, revealing that this presumed conflict wasn’t such of a problem after all.

Mapping more of the forest

This isn’t to say that people were completely inventing the idea that owls might be living in the same trees that were being targeted for clearing. The long-standing practice has been to survey sections of forests, usually less than an acre in size, then extrapolate that data to build an estimate for the rest of the woods. This limited survey was done for practical purposes, as budgeting more comprehensive studies of 1.2 million acres of Sierra Nevada forests was simply unavailable.

Fortunately, new tools are making more complete surveys easier. Researchers from the University of California, Davis, the USDA Forest Service Pacific Southwest Research Station and the University of Washington teamed up to improve our understanding where spotted owls want to live, and the size and shape of the forest overall. They collected data from past studies about where the owls are known to live, then took new measurements of those locations with LiDAR, which is essentially a form of sonar with lasers instead of sound. From a plane flying over the parks, 3D representations of each tree heights and density could be measured and compared with other data. Comparing these measurements of the trees against owl locations revealed an exciting pattern in which trees the owls actually frequented.

Spotted owls’ narrow nesting range

As it turns out, the owls don’t really care for the shorter trees that were marked for fire prevention. They’ll sometimes roost in the shorter trees that make up the forest’s understory, but they want a tall tree when it’s time build a nest. The spotted owls were actually rather picky, limiting their nesting to areas with trees that were at least 105 feet tall, but really preferring those that were at least 157 feet tall. Any place that didn’t reach over 52 feet was avoided altogether, which is great news for people concerned with fire safety.

This doesn’t mean that every shorter tree can be cleared out of the forest, but it does provide a clear path forward for forest and wildlife managers. Instead needing to make unfortunate decisions about where our priorities lie, it seems that simply getting a more detailed understanding of the owl’s ecology will allow us to have our birds and fire safety too.

Source: A Win-Win for Spotted Owls and Forest Management by Kat Kerlin, UC Davis News

On September 13th, 2017 we learned about

Fiber-optics under Stanford can feel every car tire and footstep

Every moment has repercussions, a fact my neighbors are no doubt acutely aware of on Saturday mornings when the kids wake up. Every step, thumb and bump not only hits the floor (or wall, or… ceiling), but transmits energy through those materials, much of which we end up noticing as sound. Thankfully, many of these vibrations are either too faint or the wrong frequency to be detected by our ears, but that doesn’t mean they’re not there. In fact, if you really wanted to, it turns out that it’s possible to detect and decipher almost every vibration a person’s movement might make— right down to individual footsteps along a busy sidewalk.

Wired for sound

This kind of listening is already underway at Stanford University in a project called the Big Glass Microphone. Three miles of fiber-optic cables have been laid in a loop under part of the campus, originally to investigate seismic activity. Seismographs around the world already rely on vibrations being transmitted through the ground in order to sense and triangulate activity like earthquakes, but the fiber-optics have proven to be especially sensitive. Like more traditional seismographs, the fiber-optics can measure small changes in electrical current as it’s mechanically perturbed by vibrations, but the scale of the vibrations detected provide previously unknown resolution in those readings.

As a foot steps on the ground, a relatively small, low-frequency vibration is transmitted through the sidewalk and dirt. This then hits the fiber-optic cable, which at the length of a hair is small enough to stretch slightly as the vibration passes through. With light running through the cable, these fluctuations are measured, and in most applications, thrown out as background noise that would muddy data on earthquakes or explosions. In this case, engineers are looking the other way, seeing how well they can track footsteps and cars, possibly even identifying the source of those sounds by unique vibration “signatures.”

Uses for more electronic ears

This effectively means that any material that can house a fiber-optic cable could conceivably serve as a mechanical sensor for nearby activity. In the case of a sidewalk or road, it could track the movement of people or specific cars driving by. In a building, vibrations could reveal what floor people are on to trigger changes in lighting and heating, or detect when a pipe is leaking in the wall. Or just track you even more than your phone already does.

The fact that this kind of system isn’t terribly difficult to set up is seen as both a good and a bad thing, depending on how it’s applied. It could be a relatively cheap way to get better data on how traffic operates, or to make buildings more efficient. However, any system that can track people without their knowing it is certainly open to abuse, and so many of the questions surrounding the project are now about when it should be used, rather than just if it could work.

Source: Is the ground beneath the Stanford campus listening to you? by Yasemin Saplakoglu, The Mercury News

On September 7th, 2017 we learned about

Electrifying plant matter for healthier leaves and better power storage

We’re not far off from plugging in our plants. The boundary between organic, leafy greens and metallic electronics is becoming increasingly blurred, although the end result won’t exactly look like a LED grass or an electrified salad (sadly). Still, there’s an impressive range in where plants and electronics are overlapping, starting with some well-roasted leaves that are may soon be recycled into capacitors.

Using leaves to manipulate a current

Appropriate to their names, Chinese phoenix trees are being reborn in fire as highly conductive carbon microspheres. Thankfully, the whole tree doesn’t need to be destroyed in this process, as the carbon is obtained from dead leaves that pile up in autumn. That convenience aside, you probably aren’t going to start getting capacitors out of your yard waste any time soon, as these leaves are dried, powered, heated for 12 hours at 428° Fahrenheit, mixed with potassium hydroxide, then heated again in rapidly changing temperatures up to 1,472°.

It’s a lot of work, but the payoff is a renewable source of highly porous carbon spheres that may pave the way for a variety of plant-based electronic components. The pores create a very high surface area for the tiny pellets, which may even qualify as supercapacitors transferring three times more power than graphene supercapacitors. The phoenix tree leaves work especially well, but researchers are already looking into other plants like potato skins, corn straw, pine wood and rice straw as other sources of conductive carbon.

Measuring the current in leaves

On the flip-side, if you’re looking to produce more foliage instead of electricity, there’s still a reason to wire up a plant’s leaves. Lightweight electrical sensors are being clipped onto leafy crops to measure how well they conduct electricity in differing soil conditions. Once baselines are established, these tiny variances may help measure exactly when a plant is dried out enough to need a drink, reducing a farm’s water usage.

To make these measurements, a small sensor was clipped to leave on different plants for 11 days. As the plants absorbed more or less water, their leaves would swell or shrink at the same time. That tiny change in thickness would then alter the flow of electricity through the leaf enough to be detected, and could then inform a farmer, or automated irrigation system, when plants were really ready for more water, even if the normal watering schedule didn’t sync up. These measurements were compared against a separate sensor in the soil to verify that they were on the right track. The measurements are complicated by the fact that photosynthesis can also change the flow of electricity through a leaf, but researchers are still confident this system will allow farms to be much more sensitive to their stressed plants.

Source: High-Tech Electronics Made From Autumn Leaves, Scienmag

On September 5th, 2017 we learned about

Falconry’s use of flying robots helped an injured raptor return to the wild

Looking at the handmade hoods, leather straps and small bells commonly used in falconry, one might assume that this ancient practice is still stuck thousands of years in the past. For most of us, there’s something archaic about training a raptor to perch on your arm before releasing it to chase down a small bit of prey. While those fleeting moments of drama do capture our attention, they’re only part of the story. The past four thousand years have given falconers plenty of time to develop their “art,” modernizing it to the point of incorporating autonomous flying drones as training tools. As a Canadian gyrfalcon recently found out, these efforts aren’t just for the falconer, but offer benefits to the bird as well.

Training with flying targets

One of the regular training concerns of a falconer is getting their bird to fly high enough to spot prey over a large distance. To get a falcon or hawk habituated to this hunting pattern, falconers have tried attaching bait to strings dangling from balloons or kites, hoping to lure their raptor to higher altitudes. Quadcopter drones improve on this method, since the drone can be more precise in its location and altitude, carry a camera, fly away from the raptor to imitate prey and hold up to the impact of talons a bit better than a balloon. To be on the safe side, some falconers include a parachute in the mix so that the bird and the drone can come down a bit more gently after a successful strike. An additional benefit of this kind of activity is that the birds get more mental stimulation, as well as exercise to keep their flight muscles fit.

Raptor recovery

That last point is where drones can provide therapy to injured raptors. The aforementioned gyrfalcon was found with a slice in its shoulder by a farmer, unable to fly and thus unable to feed itself. The 20-pound bird was taken to a rescue center where its wound could be tended, but that was no guarantee it would ever fully recover. While the cut healed, this female gyrfalcon wasn’t doing any active hunting and it’s muscles atrophied as a result. Fortunately, falconer Steve Schwartze was able to assist, and put the large falcon on a drone-assisted training regime to rebuild the weakened muscles. These workouts started modestly, with the raptor chasing the drone at lower altitudes to get used to moving again. As the falcon improved, the workouts became incrementally demanding, doubling the expected altitude within days.

After four months, the injured raptor was ready for release. She wasn’t necessarily “good as new,” but Schwartze felt that she could at least fly well enough to do some hunting on her own, continuing to strengthen her muscles along the way. It was a lot of work for both parties, but failure would have meant that this gyrfalcon would have probably needed care, and thus captivity, for the rest of her life.

My four-year-old asked: Did the drone fly itself, or was it remote controlled?

It’s not clear how much Schwartze steered the drone, especially since many drones offer both automatic and manual controls. Drones are sold for falconry training offering both options, and presumably advanced users switch back and forth depending on the exact type of flight they’re trying to engage in. The baseline is to automate the drone’s flight, so that may be the more common approach to this training.

My third grader asked: Don’t hawks attack the drones themselves?

The birds go after the feathery bait for the most part, which is suspended on a fishing line away from the drone itself. That’s not to say that the birds can’t handle a drone though, as a Dutch company is training birds of prey to attack drones directly, not for exercise but as security measures. It’s unclear how often those raptors will be deployed, but either way it doesn’t sound like hawks and falcons have any innate concern for quadcopters.

Source: How a falconer and a drone got an injured gyrfalcon back in the skies. by Sarah Hewitt, Motherboard