. While intriguing, we didn’t expect to see anything more about it for quite a while. But it seems ZF has in fact made a functional prototype, and you can see it in action in the video above.
In it, the system has been attached to a previous-generation
). You can also see that there are a variety of extra sensors added to the edges of the bumpers and the side mirrors to help determine when to activate the
. As the car is driving, a flexible dummy car is thrown at it, and the airbag goes off a split-second before impact, allowing the airbag to take the brunt of the impact. In fact, ZF says the system can determine whether to inflate the airbag, which is itself between 5 and 8 times the size of a typical driver airbag, and then inflate it all within 150 milliseconds.
is that the airbag works a bit like the crumple zone built into the front of a car. It adds more space for the impact to be absorbed and dissipated before reaching the occupants. According to ZF, the external airbag could reduce injury severity by 40% for passengers.
ZF’s demonstration is impressive, and it proves that this technology is much closer to reality than we first thought. Of course, we suspect it will still be several years before we see it on any production cars. Companies will surely have to do extensive testing to make sure the airbag system activates within in the necessary time frame consistently and doesn’t go off from false or misleading readings.
China has joined the US and Russia as the only nations to have successfully launched a rocket at sea. The National Space Administration’s Long March 11 took off from a launchpad on a ship in the Yellow Sea today. The rocket carried five commercial satellites (including two for a company that plans to set up a global network of internet satellites) and two research-focused experimental ones.
While the US and Russia worked with other countries on the Sea Launch platform (which wound down in 2014), China is the only nation to have launched a rocket from sea using a platform and tech it fully owns, according toTechCrunch. The launch, however, took place from a private cargo ship. SpaceX, meanwhile, has also launched and landed rockets at sea.
Since the birth of the space age, the dream of catching a ride to another solar system has been hobbled by the “tyranny of the rocket equation,” which sets hard limits on the speed and size of the spacecraft we sling into the cosmos. Even with today’s most powerful rocket engines, scientists estimate it would take 50,000 years to reach our closest interstellar neighbor, Alpha Centauri. If humans ever hope to see an alien sunrise, transit times will have to drop significantly.
Of the advanced propulsion concepts that could theoretically pull that off, few have generated as much excitement—and controversy—as the EmDrive. First described nearly two decades ago, the EmDrive works by converting electricity into microwaves and channeling this electromagnetic radiation through a conical chamber. In theory, the microwaves can exert force against the walls of the chamber to produce enough thrust to propel a spacecraft once it’s in space. At this point, however, the EmDrive only exists as a laboratory prototype and it’s still unclear whether it’s able to produce thrust at all. If it does, the forces it generates aren’t strong enough to be registered by the naked eye, much less propel a spacecraft.
Over the last few years, however, a handful of research teams, including one from NASA, claim to have successfully produced thrust with an EmDrive. If true, it would amount to one of the biggest breakthroughs in the history of space exploration. The problem is that the thrust observed in these experiments is so small that it’s hard to tell if it’s real.
Technische Universität Dresden
The resolution lies in designing a tool that can measure these miniscule amounts of thrust. So a team of physicists at Germany’s Technische Universität Dresden set out to create a device that would fill this need. Led by the physicist Martin Tajmar, the SpaceDrive project aims to create an instrument so sensitive and immune to interference that it would put an end to the did-the-EmDrive-actually-produce-thrust debate once and for all. In October, Tajmar and his team presented their second set of experimental EmDrive measurements at the International Astronautical Congress and their results will be published in Acta Astronautica this August. Based on the results of these experiments, Tajmar says a resolution to the EmDrive saga may only be a few months away.
Many scientists and engineers dismiss the EmDrive because it appears to violate the laws of physics. Microwaves pushing on the walls of an EmDrive chamber seem to generate thrust ex nihilo, which runs afoul of the conservation of momentum—it’s all action and no reaction. Proponents of the EmDrive, in turn, have appealed to fringe interpretations of quantum mechanics to explain how the EmDrive might work without violating Newtonian physics. “From the theory point of view, no one takes this seriously,” Tajmar says. If the EmDrive is able to produce thrust as some groups have claimed, he says they have “no clue where this thrust is coming from.” When there’s a theoretical rift of this magnitude in science, Tajmar sees only one way to close it: experimentation.
In late 2016, Tajmar and 25 other physicists gathered in Estes Park, Colorado, for the first conference dedicated to the EmDrive and related exotic propulsion systems. One of the most exciting presentations was given by Paul March, a physicist at NASA’s Eagleworks lab, where he and his colleague Harold White had been testing various EmDrive prototypes. According to March’s presentation and a subsequent paper published in the Journal of Propulsion and Power, he and White observed several dozen micro-Newtons of thrust in their EmDrive prototype. (For the sake of comparison, a single SpaceX Merlin engine produces around 845,000 Newtons of thrust at sea level.) The problem for Harold and White, however, was that their experimental setup allowed for several sources of interference, so they couldn’t say for sure whether what they observed was thrust.
Tajmar and the Dresden group used a close replica of the EmDrive prototype used by Harold and White in their tests at NASA. It consists of a copper frustum—a cone with its top lopped off—that is just under a foot long. This design can be traced back to the engineer Roger Shawyer, who first described the EmDrive in 2001. During tests, the EmDrive cone is placed in a vacuum chamber. Outside the chamber, a device generates a microwave signal that gets relayed, using coax cables, to antennas inside the cone.
The device wasn’t the first time the Dresden team sought to measure nearly imperceptible amounts of force. They’d built similar contraptions for their work on ion thrusters, which are used to precisely position satellites in space. These micro-Newton thrusters are the kind that were used by the LISA Pathfinder mission, which needs extremely precise positioning ability to detect faint phenomena like gravitational waves. But to study the EmDrive and similar propellantless propulsion systems, Tajmar says, required nano-Newton resolution.
Their approach was to use a torsion balance, a pendulum-type balance that measures the amount of torque applied to the axis of the pendulum. A less sensitive version of this balance was also used by the NASA team when they thought their EmDrive produced thrust. To accurately gauge the small amount of force, the Dresden team used a laser interferometer to measure the physical displacement of the balance scales produced by the EmDrive. According to Tajmar, their torsion scale has a nano-Newton resolution and supports thrusters weighing several pounds, making it the most sensitive thrust balance in existence.
But a really sensitive thrust balance isn’t much use unless you can also determine whether the detected force is in fact thrust and not an artifact of outside interference. And there are plenty of alternate explanations for Harold’s and White’s observations. To determine whether an EmDrive actually produces thrust, researchers must be able to shield the device from interference caused by the Earth’s magnetic poles, seismic vibrations from the environment, and the thermal expansion of the EmDrive due to heating from the microwaves.
Tweaks to the design of the torsion balance—to better control the EmDrive’s power supply and shield it from magnetic fields—took care of some of the interference issues, Tajmar says. A more difficult problem was how to address “thermal drift.” When power flows to the EmDrive, the copper cone heats up and expands, which shifts its center of gravity just enough to cause the torsion balance to register force that can be mistaken as thrust. Tajmar and his team hoped that changing the orientation of the thruster helped address that issue.
Over the course of 55 experiments, Tajmar and his colleagues registered an average of 3.4 micro-Newtons of force from the EmDrive, which was very similar to what the NASA team found. Alas, these forces did not appear to pass the thermal drift test. The forces seen in the data were more indicative of thermal expansion than thrust.
All hope is not lost for the EmDrive, however. Tajmar and his colleagues are also developing two additional types of thrust balances, including a superconducting balance that will, among other things, help to eliminate false positives produced by thermal drift. If they detect force from an EmDrive on these balances, there’s a high probability that it is actually thrust. But if no force is registered on these balances, it likely means that all the previous EmDrive thrust observations were false positives. Tajmar says he hopes to have a final verdict by the end of the year.
But even a negative result from that work might not kill the EmDrive for good. There are many other propellantless propulsion designs to pursue. And if scientists ever do develop new forms of weak propulsion, the hyper-sensitive thrust balances developed by Tajmar and the Dresden team will almost certainly play a role in sorting science fact from science fiction.
Skype has officially launched screen sharing for Android and iOS devices less than a couple of months after the feature rolled out for beta testers. Screen sharing can be a valuable tool for video calls, whether for personal or work purposes — say, to show a colleague the graphs you’ve been working on or to show a friend how to find a particular setting in their phone. It’s high time the feature made its way to mobile, seeing as smartphones are everywhere now.
The screen sharing feature lives within the newly redesigned "…" menu that you can see at the bottom right corner of the screen while you’re in a video call. It shares its home with call recording, subtitles and the ability to add people. While the feature is active, a banner at the top clearly indicates that it’s beaming a copy of your screen to the other person in the call.
In addition, Skype’s redesigned mobile calling experience is now also out of beta. It lets you focus on video calls by hiding call controls with a single tap and all the elements on the screen with a double tap. Skype has started rolling out the features for Android and iOS devices running iOS 12 and up.
The US Securities and Exchange Commission (SEC) is suing messaging service Kik Interactive, stating that its 2017 digital token sale, which raised $100 million, was essentially an illegal, unregistered securities offering. According to Bloomberg, this is one the highest profile cases yet where the SEC has targeted a company for not registering an offering with the regulator.
When Kik’s user base began to shrink in 2017 and the company started running out of money, it launched an ICO — an initial coin offering. This is where investors receive digital tokens instead of traditional stock. Kik called its tokens "Kin." But, according to the SEC, Kik’s offer and sale of Kin was not registered with the SEC, which considers tokens (with the exception of Bitcoin and ether) to be essentially securities. Furthermore, the SEC says Kik should have revealed the troubled state of its finances to potential investors, which it did not.
Court filings state that the SEC — which recently approved a stock exchange for tech startups — is seeking unspecified monetary penalties, alleging that Kik knew its ICO would be considered a securities offering. Kin has since launched a crowdfunding site, DefendCrypto.org, to raise money to fight the SEC’s claims, which it says "set a dangerous precedent and stifle innovation." The SEC’s co-head of enforcement, Steven Peikin, counters that "companies do not face a binary choice between innovation and compliance with the federal securities laws."
If the prevalence of abusive Google Play apps has left you numb, this latest report is for you. Carefully concealed adware installed in Google-approved apps with more than 440 million installations was so aggressive that it rendered mobile devices nearly unusable, researchers from mobile security provider Lookout said Tuesday.
BeiTaAd, as the adware is known, is a plugin that Lookout says it found hidden in emojis keyboard TouchPal and 237 other applications, all of which were published by Shanghai, China-based CooTek. Together, the 238 unique apps had a combined 440 million installs. Once installed, the apps initially behaved normally. Then, after a delay of anywhere between 24 hours and 14 days, the obfuscated BeiTaAd plugin would begin delivering what are known as out-of-app ads. These ads appeared on users’ lock screens and triggered audio and video at seemingly random times or even when a phone was asleep.
“My wife is having the exact same issue,” one person reported in November in this thread discussing BeiTaAd. “This will bring up random ads in the middle of phone calls, when her alarm clock goes off or anytime she uses any other function on her phone. We are unable to find any other information on this. It is extremely annoying and almost [makes] her phone unusable.”
Lookout’s post said the developers responsible for the 238 apps went to great lengths to conceal the plugin. Early versions of the apps incorporated it as an unencrypted dex file named beita.renc inside the assets/components directory. The renaming had the effect of making it harder for users to know the file was responsible for executing code.
Later, app developers renamed the plugin to the more opaque icon-icomoon-gemini.renc and encrypted it using the Advanced Encryption Standard. The developers then obfuscated the decryption key within the code through a series of functions buried in a package named com.android.utils.hades.sdk. In later versions still, developers used a third-party library called StringFog, which used XOR– and base64-based encoding to hide every instance of the string “BeiTa” in the files.
“All of the applications we analyzed that contained the BeiTaAd plugin were published by CooTek, and all CooTek apps we analyzed contained the plugin,” Kristina Balaam, a security intelligence engineer at Lookout, wrote in an email. “The developer also went to great lengths to hide the plugin’s presence in the app, suggesting that they may have been aware of the problematic nature of this SDK. However, we cannot attribute BeiTa to CooTek with complete certainty.”
Ars has asked representatives from both CooTek and Google to comment. This post will be updated if either or both respond.
Busted!
Lookout reported the behavior of BeiTaAd to Google, and the apps responsible were subsequently either removed from Play or updated to remove the abusive plugin. There’s no indication that CooTek will be banned or otherwise punished for breaching Play terms of service on such a mass scale and for taking the steps it did to hide the violation. The remaining 237 CooTek apps that embedded the plugin are listed at the end of Lookout’s post.
The above-linked forum discussing BeiTaAd documents that the plugin has been menacing users for at least seven months. Google’s inability to detect the abuse, either initially when the apps were submitted or later as those apps made millions of phones nearly unusable, speaks to the company’s inability—or possibly its lack of sufficient motivation—to police its marketplace against flagrant abuse. The number of installs affected demonstrates that even widely used apps have the potential to be potentially malicious.
Until Google shows signs of getting the problem of malicious and abusive apps under control, Android users should remain skeptical of Google Play and download apps sparingly.
Track of the 16-day Stratollite mission from mid-May to early June.
World View
A ground-based telescope captured this image of a Stratollite vehicle in flight during an earlier mission.
World View
On Sunday, October 1, 2017, World View’s Stratollite took part in Spaceport Tucson’s inaugural launch.
World View
The launch led to a five-day flight, breaking World View’s previous flight duration record.
World View
The instrument payload can be seen at the bottom.
World View
When we last heard from World View, the company was performing something of an advertising stunt by launching a KFC chicken sandwich into the stratosphere with its balloon technology. Now the Arizona-based company has taken a significant step toward developing its remote sensing system for practical applications.
Prior to last month, the Stratollite system had never flown for longer than five days at a stretch. But from mid-May to early June, it completed a 16-day mission that demonstrated several key abilities. For more than eight days, the company said, the balloon maintained its position over a circular area on the ground about 120km wide. It also held station over a circle with a diameter of just 9.5km for 6.5 hours.
Flying in the stratosphere at altitudes between 15 and 23km, a Stratollite uses a primary lift balloon to reach its peak altitude, and then uses secondary balloons to rapidly rise and fall through the stratosphere. By essentially riding the winds, the vehicle attempts to maintain a relatively stable position over the Earth.
By holding position, a Stratollite’s payload—typically a camera, communications equipment, or other remote sensing equipment—allows customers persistent, near-real-time observations over large areas of interest. The company will have the capability to deploy Stratollites around the world, said Ryan Hartman, World View’s president and chief executive.
Eyeing commercial flight
In an interview with Ars, Hartman said the recent test is the “culmination of a lot of work that’s been going on at World View for a year,” which included the maturing of subsystems, proving out the vehicle’s capabilities, and making the leap from short flights to a multi-week mission. The company hopes to fly 30- and 60-day missions by the end of the year, and to begin offering commercial service in 2020.
The Stratollite vehicle offers greater persistence over a location and higher quality imagery than satellites in low-Earth orbit, Hartman said, along with lower costs and longer-duration of flights than high-altitude drones. “We’re engaged with customers today, and they’re eager for us to bring this capability to the market,” he said. In late 2018, the company closed on $26.5 million in Series C funding, and Hartman says it has enough capital to reach commercial operation.
For now, controllers at the company’s facilities in Tucson, Arizona manage the flight of a Stratollite to find the most optimum altitudes for maintaining position over the ground. After World View proves the capability of the system, Hartman said the company plans to automate control of individual Stratollites so they can use their on-board sensors and a flight computer for most of a mission.
After a flight, the Stratollite vehicle makes a controlled descent so that it can recovered and flown again. In the case of last month’s flight, the Stratollite flew nearly 5,000km across Arizona, Nevada, Utah, and Oregon before landing within 120 meters of a targeted site.
