“I’m taking off, nothing will keep me on the ground“
This song text by the German rapper Sido describes the current trend in the area of drones quite well. Innovation in this field of technology has soared during the past years. According to estimations, 300,000 new drones per month are sold worldwide.
Drone taking off, Photo: shutterstock.com/Newnow
Room to move freely may soon become a rare commodity in the airspace near the ground. As a consequence, a whole new market for drone-related services is emerging. For instance, special drone insurances are offered, traffic experts call for a license for drone operators, and recycling is also an issue to be considered.
Today, “drone” stands for an unmanned, remotely piloted aerial vehicle. The name was probably inspired by the droning and buzzing sound of these flying objects. Originally, drones were developed for military purposes. They scout the enemy territory and can be used to kill by remote control. Thus, the own soldiers can avoid direct, potentially fatal, contact with the enemy.
However, by now the drone has left its niche existence in the military sector. In the meantime there are manifold civil applications. Google and Amazon are toying with the idea of having their parcels delivered by drones.1
But drones have also long since entered the mass market as high-quality gadgets for hobbyists. It’s these civil uses that boost the market.
A Patent Search on STN Shows: Drone Patents are on the Rise
We were looking for answers to the following questions: How have the patent applications evolved in drone technology, and who are the most active companies in this field?
A patent search on STN impressively illustrates the “drone hype“. The number of publications has been significantly increasing throughout the last five years (Fig. 1) and there seems to be an ongoing boom in drone technology. Our search, although just performed in early 2016, retrieved 133 drone-related patents published worldwide in 2016 alone.
Patent applications are always a clear indicator that companies have identified a market potential for a certain field of technology and want to protect their innovative products. We searched the international patent database Derwent World Patent Index® (DWPISM) by Thomson Reuters, using a keyword search combined with the Cooperative Patent Classification (CPC).
In some areas of technology it makes sense to also include relevant patent classifications into the search strategy. We have to keep in mind that not all patent documents stored with the patent authorities have been classified according to the CPC: Only about 41% of the approximately 31 million inventions recorded in DWPI have a CPC. Therefore, the relevant keywords always have to be included for the search to be successful.
Fig.1: Number of patents published worldwide, by publication year (py.b.)
When analyzing our search on the topic “drones”, we found, not surprisingly, that the top applicants are aerospace companies or large armaments manufacturers. Among the top 13 applicants are American companies like Boeing, Raytheon, Lockheed, Aerovironment and Honeywell, but also the American Armed Forces.
The most important applicants from Europe are Airbus, Thales, Bae Systems and Rolls Royce. Asia is represented by the faculty for aerospace engineering of the University of Beijing, and the Korean Samsung group. Our analysis of the patent documents resulted in the following ranking of the top applicants (Fig. 2).
Fig. 3: Percentage of drone technology patents filed by the most active countries in this field 
Where there’s light, there’s also shadow
Drones are useful and can be a real help. They carry loads, deliver parcels to their target address, fight fires from the air, or explore difficult terrain during salvage operations. As a technical gadget equipped with a camera, they enable individuals to shoot fascinating photos and videos from bird’s eye view.
However, these camera-equipped drones for civil use are very sensitive. You have to be very skilled to properly operate such a drone by remote control, and a crash will usually result in a total write-off
Fig. 4: Patent drawing of the GimBall drone from patent EP2813428, published on December 17, 2014
Flyability, a Lausanne-based startup from Switzerland, has found a creative solution to this problem. Their drone GimBall is protected against collisions by a spherical carbon-fiber frame. It resembles a football with its polygonal facets formed by carbon-fiber bars.3The drone is safely hosted inside while the rotor blades are still able to move freely.
In addition, a flight control algorithm ensures that the drone will remain in stable flight after a collision. It can even “learn” from collisions and find its way on its own. In February 2015, the company’s GimBall drone won the first prize in the international “Drones for Good” contest to which one million US dollars was allocated.
There are virtually no limits to the imagination of engineers and developers. In January 2016, the Chinese drone manufacturer Ehang presented the first drone that is able to carry human beings.
As futuristic as it may sound, according to Ehang passengers simply have to take a seat in the drone and enter their target destination via touchscreen, and the drone will do the rest. The Ehang 184 flies at a height of about 500 m and has enough power for a 23-minute flight4.
Fig. 5: Ehang 184
In December 2015, Twitter published their patent US20150362917 under the title “messaging-enabled unmanned aerial vehicle”. With this patent the social networking service claims the invention of a camera-equipped drone that is connected to, communicates with, and is flown via social networks.
The photos or videos sent by the drone can also be uploaded directly on the owner’s Twitter account using the Periscope app. Thus, the so-called Dronies (a word made up of “drone” and “selfie”) are created.
However, as it is often the case with ground-breaking inventions, the drone technology also has its dark side.
Drones can be abused for criminal purposes such as assassinations by remote-control, the clandestine transport of drugs or weapons, espionage, or serious violation of privacy through aerial surveillance.
The media increasingly report on drones that were found trespassing in the airspace above nuclear power plants, airports, or government buildings. So it comes as no surprise that innovation in the anti-drone defense sector is flourishing as well.
There are various approaches to this issue, but they generally follow this three-step procedure: detecting the unmanned aerial vehicle, appropriately classifying it as “dangerous” or “harmless”, and, if necessary, destroying or capturing the attacking drone.
Defense by Mechanical Means
The Dutch police have developed quite an unorthodox solution to this problem. They are training birds of prey to catch drones in flight and carry them away.
Another means of defense, reminding of a combat technique used by Roman gladiators, is to catch the drone in a net that is aimed and thrown by another drone. The enemy drone is immobilized by the net and, while still entangled, taken away by the other drone. This method was developed by the University of Michigan.5
Fig. 6: Patent drawing of an enemy drone caught in a net attached to another drone. The Russian patent RU2565863 was published on October 20, 2015
A similar idea has occurred to the Russian air force academy (Fig.6). However, the Russian patent also covers the material of the net, an extremely strong and tear-resistant polymer.
Defense by Taking Over or Interfering with the Drone’s Communication
Anti-drone defense is a typical military application. And, of course, the military wants to operate in secret. As a consequence, military inventions should be hidden from the eyes of the users of patent databases. Therefore, some inventions will probably never be disclosed at all for reasons of security (see article Office 99 in our archive), or at least the information will be very hard to find.
Fig. 7: Patent drawing from EP2853974 by Airbus Defence & Space GmbH
One example is patent EP2853974 published on April 1, 2015 by Airbus Defence & Space GmbH under the innocuous title “Method for autonomous controlling of a remote controlled aerial vehicle and corresponding system”. The patent drawing, too, does not really help understand the invention. At least the object below number 50 can be identified as a type of drone.
According to the description of the drawing, the three-dimensional box represents the aerial space. The positions marked 15 are potential landing places of the captured drone. The invention’s objective is to gain control over the drone by taking over its communication and data links.
But how about drones that do no longer need remote control? Drones that can fly autonomously, are able to recognize and avoid obstacles and have a tailor-made algorithm which continuously processes data from the drone’s flight environment and transforms them into a virtual landscape?
In this case the defense methods described above are useless. It is neither possible to purposefully interfere with the drone’s communication, nor can the drone be caught by other drones. The American startup Skydio has developed such an autonomous drone. Its core part is an algorithm computing the three-dimensional environment in which the drone is flying.
A video shows the drone following several cyclists on their way through open fields and the woods. This technological trend is in the air: it started with autonomous cars, autonomous drones are next.