New from TrackingPoint

Saturday, October 25th, 2014

TrackingPoint recently introduced the Shotglass:

The Shotglass can be used to aim and fire the weapon from complete concealment cover. It can record video. It’s most likely use in the real world, though, is as a way for the spotter to direct the sniper on target. We expect we will see more of these used with TrackingPoint’s long-range bolt action rifles than with its ARs, but time will tell.

Tracking Point Shotglass

The company now offers three ARs, including a .300 WinMag model:

Tracking Point AR in 300 WinMag

Transportation, Divergence, and the Industrial Revolution

Tuesday, October 21st, 2014

Nick Szabo explores transportation, divergence, and the Industrial Revolution:

After about 1000 AD northwestern Europe started a gradual switch from using oxen to using horses for farm traction and transportation.  This trend culminated in an eighteenth-century explosion in roads carrying horse-drawn carriages and wagons, as well as in canals, and works greatly extending the navigability of rivers, both carrying horse-drawn barges. This reflected a great rise in the use of cultivated fodder, a hallmark of the novel agricultural system that was evolving in northwestern Europe from the start of the second millennium: stationary pastoralism.  During the same period, and especially in the seventeenth through nineteenth centuries, most of civilized East Asia, and in particular Chinese civilization along its coast, navigable rivers, and canals, faced increasing Malthusian pressures and evolved in the opposite direction: from oxen towards far more costly and limited human porters. Through the early middle ages China had been far ahead, in terms of division of labor and technology, of the roving bandits of northern Europe, but after the latter region’s transition to stationary pastoralism that gap closed and Europe surged ahead, a growth divergence that culminated in the industrial revolution.  In the eighteenth century Europe, and thus in the early industrial revolution, muscle power was the engine of land transportation, and hay was its gasoline.

Metcalfe’s Law states that a value of a network is proportional to the square of the number of its nodes.  In an area where good soils, mines, and forests are randomly distributed, the number of nodes valuable to an industrial economy is proportional to the area encompassed.  The number of such nodes that can be economically accessed is an inverse square of the cost per mile of transportation.  Combine this  with Metcalfe’s Law and we reach a dramatic but solid mathematical conclusion: the potential value of a land transportation network is the inverse fourth power of the cost of that transportation. A reduction in transportation costs in a trade network by a factor of two increases the potential value of that network by a factor of sixteen. While a power of exactly 4.0 will usually be too high, due to redundancies, this does show how the cost of transportation can have a radical nonlinear impact on the value of the trade networks it enables.  This formalizes Adam Smith’s observations: the division of labor (and thus value of an economy) increases with the extent of the market, and the extent of the market is heavily influenced by transportation costs (as he extensively discussed in his Wealth of Nations).

How Palmer Luckey Created Oculus Rift

Monday, October 20th, 2014

If there is a case to be made that unconventional schooling, without busywork or fixed schedules, helps unleash creativity, Palmer Luckey, creator of the Oculus Rift, might well be Exhibit A for the prosecution:

His mother, Julie, home-schooled all four of her children during a period of each of their childhoods (Luckey’s father, Donald, is a car salesman), but Palmer was the only one of the kids who never went back; he liked the flexibility too much. In his ample free time, he devoted most of his considerable energy to teaching himself how to build electronics from scratch.

No one else in Luckey’s family was especially interested in technology, but his parents were happy to give over half of the garage at their Long Beach, California, home to his experiments. There, Luckey quickly progressed from making small electronics to “high-voltage stuff” like lasers and electromagnetic coilguns. Inevitably, there were mishaps. While working on a live Tesla coil, Luckey once accidentally touched a grounded metal bed frame, and blew himself across the garage; another time, while cleaning an infrared laser, he burned a gray spot into his vision.

When Luckey was 15, he started “modding” video game equipment: taking consoles like the Nintendo GameCube, disassembling them, and modifying them with newer parts, to transform them into compact, efficient and hand-crafted devices. “Modding was more interesting than just building things entirely using new technologies,” Luckey told me. “It was this very special type of engineering that required deeply understanding why people had made the decisions they made in designing the hardware.”

Luckey soon became obsessed with PC gaming. How well, he wondered, could he play games? “Not skill level,” he clarified to me, “but how good could the experience be?” By this time, Luckey was making good money fixing broken iPhones, and he spent most of it on high-end gaming equipment in order to make the experience as immersive as possible. At one point, his standard gaming setup consisted of a mind-boggling six-monitor arrangement. “It was so sick,” he recalled.

But it wasn’t enough. Luckey didn’t just want to play on expensive screens; he wanted to jump inside the game itself. He knew the military sometimes trained soldiers using virtual reality headsets, so he set out to buy some — on the cheap, through government auctions. “You’d read that these VR systems originally cost hundreds of thousands of dollars, and you thought, clearly if they’re that expensive, they must be really good,” Luckey said. Instead, they fell miles short of his hopes. The field of view on one headset might be so narrow that he’d feel as if he was looking through a half-opened door. Another might weigh ten pounds, or have preposterously long lag between his head moving and the image reacting onscreen — a feature common to early VR that literally makes users nauseated.

So Luckey decided to do what he’d been doing for years with game consoles: He’d take the technology apart, figure out where it was falling short and modify it with new parts to improve it. Very quickly, he realized that this wasn’t going to be simple. “It turned out that a lot of the approaches the old systems were taking were dead ends,” he said.

The problem was one of fundamental design philosophy. In order to create the illusion of a three-dimensional digital world from a single flat screen, VR manufacturers had typically used complex optical apparatuses that magnified the onscreen image to fill the user’s visual field while also correcting for any distortion. Because these optics had to perform a variety of elaborate tricks to make the magnified image seem clear, they were extremely heavy and costly to produce.

Luckey’s solution to this dilemma was ingeniously simple. Why use bulky, expensive optics, he thought, when he could put in cheap, lightweight lenses and then use software to distort the image, so that it came out clear through them? Plus, he quickly realized that he could combine these lenses with screens from mobile phones, which the smartphone arms race had made bigger, crisper and less expensive than ever before. “That let me make something that was a lot lighter and cheaper, with a much wider field of view, than anything else out there,” he said.

From 2009 to 2012, while also taking college classes and working at the University of Southern California’s VR-focused Institute for Creative Technologies, Luckey poured countless hours into creating a working prototype from this core vision. He tinkered with different screens, mixed and matched parts from his collection of VR hardware, and refined the motion tracking equipment, which monitored the user’s head movements in real-time. Amazingly, considering the eventual value of his invention, Luckey was also posting detailed reports about his work to a 3-D gaming message board. The idea was sitting there for anyone to steal.

But, as Brendan Iribe put it to me, “Maybe his name is Luckey for a reason.” By that point, no one was interested in throwing more money away on another doomed virtual reality project.

Then, in early 2012, luck struck again when the legendary video game programmer John Carmack stumbled onto his work online and asked Luckey if he could buy one of his prototypes. Luckey sent him one for free. “I played it super cool,” he assured me. Carmack returned the favor in a big way: At that June’s E3 convention — the game industry’s gigantic annual commercial carnival — he showed off the Rift prototype to a flock of journalists, using a repurposed version of his hit game “Doom 3” for the demonstration. The response was immediate and ecstatic. “I was in Boston at a display conference at the time,” Luckey said, “and people there were like, ‘Dude, Palmer, everyone’s writing articles about your thing!’”

The rest, as they say, is virtual history: Over the next 21 months, Luckey partnered with Iribe, Antonov and Mitchell, launched a Kickstarter campaign that netted $2.4 million in funding — nearly ten times its initial goal — and joined the Facebook empire, thereby ensuring the company the kind of financial backing that most early-stage tech companies can only dream of.

The Oculus Rift is now entering its final stages of development — it’s slated for commercial release next year — and this fall Samsung will release a scaled-down product for developers and enthusiasts, powered by Oculus technology, that will clip over the company’s Galaxy Note 4 smartphone. But Luckey knows that success is by no means assured. “To this point, there has never been a successful commercial VR product, ever,” Luckey told me. “Nobody’s actually managed to pull this off.” Spend a few minutes inside the Rift, though, and one can’t help but believe that Luckey will be the one to do it.

Apple’s Next Big Imitative Leap

Monday, October 20th, 2014

Apple is just buying time until its next big imitative leap:

Samsung debuted its first, much maligned and hugely successful Galaxy Note — the first phone with a bigger-than-5-inch screen — in September, 2011. For two years afterwards, Apple was content to present incremental improvements to the iPhone. Compared with the iPhone 5, the iPhone 5s just added a fingerprint sensor and an improved camera (plus a few other features that most consumers didn’t care about).

Meanwhile Apple carefully observed the “phablet” market, watched other handset makers follow Samsung’s example and erode its market share, and experimented with ways to make a big phone easier to navigate one-handed. It struck just when Samsung started posting lower profits, because of the increased competitive pressure.

It was a perfectly-timed attack and, after setting a first-weekend record — 10 million iPhones sold — iPhone 6 and iPhone 6 Plus are continuing their rampage. Apple chief executive Tim Cook said yesterday that the first sales month for the two new phones was the company’s best ever “by a lot. A whole lot.”

The iPad Air 2′s most important improvements on last year’s device are, again, a fingerprint sensor and a better camera. As with iPhone 5s in 2013, it may appear as if Apple is stuck in a rut of timid, incremental innovation. My bet, however, is that it’s watching another innovator collect bumps, get bad reviews, then get things right. Once that innovator’s success is assured, Apple will pounce.

This time it isn’t a Samsung product Apple is watching, but Microsoft’s Surface Pro.

Microsoft hit on the idea of producing a tablet-laptop cross in 2012, incurring losses and writing off inventory as it refined the concept. This year, it finally produced a device that reviewers liked — the Surface Pro 3. It’s reasonably convincing both as a laptop and as a tablet, albeit a large and heavy one. Microsoft has not released numbers, saying only that the Pro 3 was its fastest-selling tablet yet — the company underestimated demand, creating shortages in some markets.

The analysis company Gartner puts the Surface Pro in the same category — “premium ultra-mobile” computers — as Apple’s MacBook Air laptops.

Compact Fusion Reactor

Wednesday, October 15th, 2014

Lockheed Martin’s Skunk Works plans to develop a compact fusion reactor (CFR):

Until now, the majority of fusion reactor systems have used a plasma control device called a tokamak, invented in the 1950s by physicists in the Soviet Union. The tokamak uses a magnetic field to hold the plasma in the shape of a torus, or ring, and maintains the reaction by inducing a current inside the plasma itself with a second set of electromagnets. The challenge with this approach is that the resulting energy generated is almost the same as the amount required to maintain the self-sustaining fusion reaction.

Compact Fusion Reactor Diagram

The problem with tokamaks is that “they can only hold so much plasma, and we call that the beta limit,” McGuire says. Measured as the ratio of plasma pressure to the magnetic pressure, the beta limit of the average tokamak is low, or about “5% or so of the confining pressure,” he says. Comparing the torus to a bicycle tire, McGuire adds, “if they put too much in, eventually their confining tire will fail and burst—so to operate safely, they don’t go too close to that.” Aside from this inefficiency, the physics of the tokamak dictate huge dimensions and massive cost. The ITER, for example, will cost an estimated $50 billion and when complete will measure around 100 ft. high and weigh 23,000 tons.

The CFR will avoid these issues by tackling plasma confinement in a radically different way. Instead of constraining the plasma within tubular rings, a series of superconducting coils will generate a new magnetic-field geometry in which the plasma is held within the broader confines of the entire reaction chamber. Superconducting magnets within the coils will generate a magnetic field around the outer border of the chamber. “So for us, instead of a bike tire expanding into air, we have something more like a tube that expands into an ever-stronger wall,” McGuire says. The system is therefore regulated by a self-tuning feedback mechanism, whereby the farther out the plasma goes, the stronger the magnetic field pushes back to contain it. The CFR is expected to have a beta limit ratio of one. “We should be able to go to 100% or beyond,” he adds.

This crucial difference means that for the same size, the CFR generates more power than a tokamak by a factor of 10. This in turn means, for the same power output, the CFR can be 10 times smaller. The change in scale is a game-changer in terms of producibility and cost, explains McGuire. “It’s one of the reasons we think it is feasible for development and future economics,” he says. “Ten times smaller is the key. But on the physics side, it still has to work, and one of the reasons we think our physics will work is that we’ve been able to make an inherently stable configuration.” One of the main reasons for this stability is the positioning of the superconductor coils and shape of the magnetic field lines. “In our case, it is always in balance. So if you have less pressure, the plasma will be smaller and will always sit in this magnetic well,” he notes.

The Bot Crossing Point

Wednesday, October 15th, 2014

In the last quarter of 2011, more iPhones were sold than babies were born, John Robb notes:

That’s interesting because that is also the quarter that Siri shipped.

FYI: Apple’s Siri is the first mass market bot that was designed to act like a human.

In hindsight, this apparently minor observation may be considered something more important: a tombstone milestone for humanity.

It’s the quarter when our future replacements on this planet began to outpace us.


Tuesday, October 14th, 2014

The Russians have been spying on foreign powers — shocking, I know — using software that researchers have dubbed Sandworm:

Although iSight only has a small view of the number of victims targeted in the campaign, the victims include among others, the North Atlantic Treaty Organization, Ukrainian and European Union governments, energy and telecommunications firms, defense companies, as well as at least one academic in the US who was singled out for his focus on Ukrainian issues. The attackers also targeted attendees of this year’s GlobSec conference, a high-level national security gathering that attracts foreign ministers and other top leaders from Europe and elsewhere each year.

It appears Sandworm is focused on nabbing documents and emails containing intelligence and diplomatic information about Ukraine, Russia and other topics of importance in the region. But it also attempts to steal SSL keys and code-signing certificates, which iSight says the attackers probably use to further their campaign and breach other systems.

The researchers dubbed the operation “Sandworm” because the attackers make multiple references to the science fiction series Dune in their code. [...] It was encoded references to Dune — which appear in URLs for the attackers’ command-and-control servers — that helped tie some of the attacks together. The URLs include base64 strings that when decoded translate to “arrakis02,” “houseatreides94,” and “epsiloneridani0,” among others.

“Some of the references were very obscure so whoever was writing the malware was a big Dune geek,” says John Hultquist, senior manager for iSight’s Cyber Espionage Threat Intelligence team.

“Once men turned their thinking over to machines in the hope that this would set them free. But that only permitted other men with machines to enslave them.”

Forget Electric Cars

Wednesday, October 8th, 2014

The co-CEOs of Nat G CNG Solutions urge us to forget electric cars:

At Mike Scully’s Apple Towing in Houston, just one of their big Ford F650 tow trucks saves more gasoline each year than 20 Nissan Leaf electric cars. When it comes to reducing carbon dioxide, nitrogen oxides and other pollutants, Mike’s F650s are equally impressive, and his fuel cost per mile is about the same as that of a four-seat Jeep Wrangler. What is Apple Towing’s secret? The F650 tow trucks run on natural gas, which they refuel for less than $1.70 per gasoline-gallon equivalent, or gge.

PIRA Energy Group estimates that natural gas in transportation will approach 800 million gges this year. Do some simple math and it quickly becomes apparent that natural-gas vehicles (NGVs) will displace 10-12 times more gasoline and diesel than the 250,000 electric cars currently on the road. When complete, Apple Towing’s small fleet of 24 natural-gas tow trucks will displace more gasoline than around 700 Chevy Volts. And here is a nice side benefit: Those Volts would cost federal taxpayers a whopping $5.3 million in subsidies while Mr. Scully’s F650 Fords cost them nothing.


Apple Towing’s Mr. Scully asked our company, Nat G Solutions, to upgrade his F650s and at the same time install a natural-gas fueling compressor in his parking lot and hook it up to his city gas line. The great infrastructure crisis disappeared.


For diesel trucks, a new generation of retrofit systems — from companies like NGV Motori USA and Landi Renzo — allow us to upgrade the big diesel engines to run on a 60/40 blend of natural gas and diesel, which is combined in real-time inside the engine. If the compressed natural gas runs dry, the truck switches back to 100% diesel and keeps on driving. This dual-fuel approach is now opening the door for long-haul natural-gas trucking without the need for multibillion-dollar infrastructure incentives or even the need to go out and buy new tractor-trailers.


Ford has been leading the way in building “gas prepped” trucks — typically a $350 option — which enables any Ford-certified “qualified vehicle modifier” to install an approved natural-gas system without affecting the original power-train warranty. Nearly the entire F-series line, from F150s to F650s, is now available in a natural-gas-ready version as are the Transit and E-series work vans. GM has taken a more incremental approach, with fewer models available so far, but the industry has responded by creating aftermarket EPA-certified upgrades for nearly every GM truck and SUV on the market.

Most of this new technology remains aimed squarely at the work-truck market, exactly where it ought to be focused. This segment drives the most miles, drives the biggest vehicles, and burns the most fuel.

Elon Musk on Mars Colonisation

Monday, October 6th, 2014

We’ve been sending unmanned probes to Mars, and, as Elon Musk likes to point out, they are very expensive probes:

They aren’t exactly bargain-basement. The last RC car we sent to Mars cost more than $3 billion. That’s a hell of a droid. For that kind of money, we should be able to send a lot of people to Mars.

A Soft Exoskeleton

Thursday, October 2nd, 2014

Soft ExoskeletonDARPA has granted $2.9 million to Harvard researchers developing a soft exoskeleton made of spandex, nylon, cables, and motors:

The Harvard exoskeleton is highly efficient because it applies force in a way that closely aligns with the natural movements of muscles and tendons. Sensors monitor the wearer’s motion, and battery-powered motors move cables to pull up on the heel, or on part of the leg near the hip — adding a propelling tug at just the right moment as the wearer steps forward. “It’s quite lightweight, flexible, and conformal,” says Conor Walsh, a professor of mechanical and biomedical engineering at Harvard. “It doesn’t disrupt normal walking and movement.”

The machine is designed to fit easily under clothes, and novel, soft sensors made of silicone rubber are integrated into the suit. The sensors, developed at another lab at Harvard, include embedded channels filled with a conductive liquid that changes in resistivity as the silicone is stretched.

Ultra Heavy-lift Amphibious Connector

Friday, September 26th, 2014

The US Marine Corps recently showed off a half-scale prototype of its Ultra Heavy-lift Amphibious Connector (UHAC):

The tracks, which are made of what the Marines call “captured-air foam blocks,” extend like flippers to propel the craft through the water. When it hits the beach, the foam flattens to become like the tracks on a tank or a bulldozer, only much softer, according to a report from Stars and Stripes.

Last week, the UHAC prototype, which is about half the size of envisioned production models, carried an assault vehicle from the Rushmore to the beach. The Marine Corps says a full-size UHAC would be able to carry much more.

“The full-scale model should be able to carry at least three tanks and a HMMVW (High Mobility Multipurpose Wheeled Vehicle),” Gunnery Sgt. Joseph Perera, the Warfighting Lab’s Infantry Weapons Project officer, said in a statement. That’s about three times the load that the Corps’ current craft assigned to the task, called a Landing Craft Air Cushion (LCAC), can handle.

It also will be able to surmount bigger obstacles. While an LCAC can only get over a 4-foot-high sea wall, a full-size UHAC will be able to get over sea walls as high as 10, 12 or even 16 feet, according to the Corps.

The UHAC prototype type is not armored or armed, but Perera said production models would have armor plating and a .50-caliber machine guns for protection.
They also would be much faster. The prototype could only go 5 mph on the water, but a full-size UHAC should do 25 mph, Gen. Kevin Killea, commander of the Corps’ Warfighting Lab, told Stars and Stripes.

The UHAC prototype used last week is the third in the program, built upon a concept originally proposed by the Hawaii-based shipbuilding and research firm Navatek, Ltd.

“There has been a one-fifth scale model, then a one-quarter scale model and this is a half-scale model, so we have been progressing,” Frank Leban, program officer at the Office of Naval Research, said in a statement. “Every vehicle has incorporated more features and technology to help get us to the full scale.”

3D-Printed Drone

Friday, September 26th, 2014

Researchers have devised a 3D-printed drone, using a Google Nexus 5 smartphone for avionics:

FORTIS Exoskeleton

Thursday, September 25th, 2014

Military work is physically demanding — even the non-combat work — and Lockheed Martin’s FORTIS Exoskeleton is designed to help:

Called the FORTIS, the exoskeleton is able to support tools of up to 36 pounds and transfer that load from a worker’s hands and arms to the ground. The goal is to lighten workers’ loads, ultimately making them more productive and skilled at their jobs.

FORTIS Exoskeleton

he anodized aluminum and carbon fiber skeleton weighs 30 pounds, and follows along the outside of a human’s body. It has joints in the parts of the body that would regularly have joints (ankle, knee, hip) and flexes from side to side at the waist. Miller says the skeleton was designed for complex environments — whoever is wearing it can climb stairs or a ladder, squat and generally move business as usual in the exoskeleton. Tools mount to the front of the FORTIS and that weight is directed through the joints in the hip and down to the floor, relieving stress on the entire body, including the feet and ankles.

Lockheed YO-3A Quiet Star

Thursday, September 25th, 2014

The U-2 and SR-71 were fast, high-flying reconnaissance aircraft, but the slow, low-flying YO-3A Quiet Star handled reconnaissance in its own way:

Acoustically undetectable from the ground when flying around 1,200 feet, the YO-3A silently observed troop movement in Vietnam. Some pilots have also said that they went unnoticed by the enemy just 200 feet below them.

Lockheed YO-3A in Flight

Nearly silent, this reconnaissance aircraft would patrol in the dead of night with absolutely no lights on. Using a downward facing night vision aerial periscope, the two man crew would fly above the enemy, taking notes of what they saw as well as call in support and direct artillery fire if needed.

Lockheed YO-3A Mission Equipment

What made this aircraft so quiet was mainly its slow turning propeller and heavily modified exhaust. The muffler ran the length of the aircraft which enabled sound to be incredibly dampened. Everything about this aircraft was designed to reduce noise. Instead of using gears, a belt system powered the propeller and the low rpm engine kept things quiet while eliminating vortices. The Quiet Star also had radar absorbing paint and it was said that once the pilot switched off their transponder, the tower couldn’t pick them up on radar.

The YO-3A’s were successful in their missions and thanks to being nearly completely silent, never took a round or were shot down during their time in Vietnam. In fact, they would have been used more if they weren’t deployed so late in America’s involvement of the war.

The Revenge of the Circulating Fan

Wednesday, September 24th, 2014

Used in combination with air-conditioning, fans could lower energy use by 30–70 percent:

Compressor-based cooling or air-conditioning (AC) puts increasing pressure on electric grids worldwide. In the USA, the birthplace of the technology, AC accounts for approximately 20% of year-round electricity consumption by American households, and 15% of total electricity use. The widespread use of AC explains in large part why Americans use so much more electricity than Europeans: AC electricity use by an American household equals 60% of all electricity used by the average European household.

Except for the few temperate regions on the West Coast, air conditioners are now standard in most American homes. While only 12% of American households had AC in 1960, this number increased to 87% in 2009. Furthermore, the average air-conditioned home consumed 37% more energy for cooling in 2005 than it did in 1993 – in spite of a 28% increase in AC energy efficiency. Part of the increase in energy use is due to the switch from window units (which cool one room) to central air-conditioning (which cool the whole building), and in part to the growing cubic footage of houses and apartments.

Even worse is the impact of air-conditioning on peak power demand. Obviously, the use of AC is not spread equally throughout the year, but concentrated in the summer months. On very hot days, many air-conditioning units are set to a maximum position, and as a consequence demand for electricity spikes. Hundreds of American power plants and a great many miles of transmission and distribution lines are needed on average only two or three days per year, while they sit idle for the rest of the time. Peak power demand is growing faster than average power demand, and compressor-based cooling is an important reason for this.


Air-conditioning is the least energy efficient way of cooling people, because it implies that all the air in an enclosed space needs to be refrigerated (and, if necessary, dehumidified) in order to cool the occupants. The larger the space and the fewer the people within it, the more energy it will take to cool each occupant. Like air-conditioning, circulating fans cool people by encouraging heat loss from the body through convection and evaporation. However, unlike air-conditioning, moving air around requires much less energy than refrigerating it.

Moreover, the cooling effect of circulating fans can be applied locally and has immediate effect. Fans circulate air around the body, while leaving the air in unoccupied parts of the space unaffected. Likewise, it is not necessary to keep the air circulating when nobody is around. Upon entering a room, turning on a fan has an immediate effect. Air-conditioning, on the other hand, needs time to cool down a space. As a consequence, a space will often be air-conditioned even when nobody is around, in order to provide immediate comfort when somebody enters it.


The cooling effect of circulating fans is substantial. An air speed of roughly 1 m/s is capable of offsetting a 3°C (5.4°F) increase in indoor temperature, while an air speed of 3 m/s has a cooling effect of roughly 7°C (12.6°F). [10]


A 2013 study found that subjects were comfortable up to 30°C (86°F) and 60% relative humidity with an air speed of 1.2 m/s, and up to 30°C and 80% relative humidity with an air speed of 1.6 m/s. At 60% relative humidity, subjects would be comfortable at temperatures higher than 30°C, but these conditions were not investigated. During the experiment, which took place in a climate chamber, subjects were wearing light clothing (0.5 clo) and performed light activity (for example, computer work at a desk).

If fans are so effective and comfortable, why is their use not more widespread?

Because until very recently, international comfort standards limited air movement indoors to a meagre 0.2 m/s in order to avoid drafts.

Air conditioning did away with traditional building techniques:

Traditional buildings in hot climates kept solar radiation out by using heavy construction materials, big eaves, reflective tin roofs, and growing shade trees around the house. Air conditioning did away with all these building elements and stimulated the use of lighter and cheaper building materials. Office blocks with H, T, and L-shaped footprints, which facilitated cross-ventilation, were replaced by massive, square blocks with very deep floor plans. Completely new building types emerged, such as office towers with fully glazed facades or enclosed shopping centres, which would be simply uninhabitable without air-conditioning because of the greenhouse effect.