Can Drones Replace Satellites?

Oh c'mon. Drones are going to replace everything: animal, mineral and vegetable. Mere machines like satellites don't have a chance. JL

Peter Feuilherade reports in the International Electrotechnical Commission:

Compared with satellite imagery, drone mapping can produce data faster, at a higher resolution and a far cheaper price.

Unmanned aerial vehicles (UAVs) have rapidly entered the civilian market after having been widely developed for military operations. They already have a disrupting effect on a wide range of commercial activities and that’s just a beginning.

Cheaper and more popular than ever

The growing availability of affordable drones in the sub-USD 1 000 consumer marketplace is raising awareness of their potential commercial as well as leisure applications, gradually replacing the public perception of drones as tools to track and kill targets in military operations abroad. The term 'drone' refers to aircraft without a human pilot aboard which can be operated autonomously through on-board computers or by remote control; they are also known as unmanned aerial vehicles (UAVs) or unpiloted air systems (UAS). Drones can be powered by an internal combustion engine, batteries, solar photovoltaic (PV) systems or a combination of these.

From agriculture, to aerial photography

Agriculture, disaster relief, conservation, wildlife monitoring and aerial photography are the areas where the use of commercial drones is currently showing the fastest growth.

Agricultural researchers are experimenting with the use of drones to monitor the growth of crops. The use of aerial video in the energy sector, especially oil and gas, is another key application. Compared with satellite imagery, drone mapping can produce data faster, at a higher resolution and a far cheaper price.

Other emerging applications include scanning disaster sites and nuclear plants for signs of radiation, surveying infrastructure such as power pylons and telecoms facilities and carrying out building surveys.

Aid organizations like Medecins Sans Frontieres have tested the ability of drones to carry samples and deliver emergency medical supplies in isolated areas. The World Wildlife Fund and other conservationists are using cheap drones with cameras, flown by auto-pilot linked to GPS, to count endangered animal populations, from orang-utans in Sumatra to rhinos in South Africa. And police forces and fire services are using drones for search and rescue as well as surveillance.

In February 2015 China's biggest internet retailer, Alibaba, ran a three-day trial of drone based deliveries to hundreds of customers near distribution centres in Beijing, Shanghai and Guangzhou. While global heavyweights like Amazon, Google and UPS pursue their own private trials using drones to deliver packages automatically once regulatory issues are resolved, drone delivery services have been successfully carried out in Germany and France (the latter on a test basis).

Huge potential market

The commercial drone market has benefited from the huge investments in military drones. Advances in high density batteries and GPS systems have made it possible for drones to travel longer distances autonomously, while costs have fallen. By the end of 2015, according to accounting and consulting firm Deloitte, up to one million non-military drones costing upwards of USD 200 could be in use globally, raising questions about safety, regulation and technical standards.

Commercial drones range in price from small, semi-autonomous rotorcraft priced at around USD 1 000 up to large, fully-autonomous, fixed wing type aircraft costing more than USD 1 million. While their capabilities and uses vary as widely as their prices, they all have a common function: to gather information and data from the air using on-board cameras or other sensors.

The ability of drones to operate autonomously at low cost comes from the use of commodity electronics developed for consumer gadgets such as mobile phones. These contain a number of devices essential for drone flight, such as GPS units, wireless transmitters, signal processors, micro-electromechanical system (MEMS) gyroscopes and accelerometers. The flight controller is the nerve centre of a drone, collecting data from a host of on-board sensors including these devices as well as barometric pressure and airspeed sensors.

Gimbal-stabilized cameras on drones permit smooth aerial video and photography, object tracking, night time recording and infrared surveillance.

Drones are generally connected to ground bases which are often handheld computers, allowing an operator to observe the drone’s flight patterns and data gathering through a display screen on the ground connected to a camera or cameras on the drone. This allows an operator to maintain control over the drone in flight even if it leaves the line of sight of the operator, ensuring that the drone does not become lost or crash in the event that it goes off course.

Lithium polymer batteries that power high-end consumer drones can keep the craft airborne for up to 25 minutes between charges, while at the other extreme, a solar-powered drone flew for 14 days and 22 minutes in 2010, setting a world record for the longest drone flight.

Avoiding injury and accidents

The commercial use of drones of all sizes poses questions about physical safety, the risk of injuring people or causing damage to property (although in most cases pilot error is to blame).

Their battery life is limited, cloud cover and solar flares can interfere with GPS and in bad weather strong winds can blow them off course and rain can affect their motors. Malware could allow hackers to control a drone remotely for criminal and terrorist purposes. These risk factors have spurred the rapid development of a wide range of technologies to enhance the safety of drones in flight, improve communication between them and ensure they do not collide with each other.

These include GPS geo-fencing, which keeps a drone within a certain altitude and geographic region, and systems which enable it to land safely in the event of a malfunction or an emergency, or to return home automatically if flown out of the range of its remote control device.

Improving drone detection

Companies are also developing a range of systems that can detect small unmanned aerial craft. One system, called Automatic Dependent Surveillance-Broadcast (ADS-B), includes small on-board GPS-based devices and is light enough to be carried by many drones. It repeatedly broadcasts not just the craft’s position but other data, including its flight path, and receives similar coordinates from any nearby aircraft. Another system is based on electronic scan FM (frequency modulated) continuous wave Doppler technology; its developers say it can even distinguish drones from birds to reduce false alarm rates.

And with over 600 companies building differing versions of drone hardware for various applications, efforts are under way to promote a single umbrella software platform with which all components would be compatible.

Enter policy decisions

In March 2015 the Federal Aviation Administration (FAA) unveiled a new policy to speed up approval for commercial drone flights in the US. The new rules would allow companies that already have exemptions from a ban on commercial drones to use the aircraft at altitudes of up to 200 feet during daylight hours and within the operator's visual line of sight.

Many US companies say the country is lagging in the commercial exploitation of drones compared with Europe, where regulations are generally less onerous and several commercial operators are actively adopting the technology. In the UK, between January and October 2014 the number of organizations permitted by the Civil Aviation Authority to fly drones under 20 kg rose by 80 %. The European Aviation Safety Agency (EASA) has set out proposed guidelines based on "safe and proportionate rules" for the integration of drones into European civil airspace. In the view of the Aviation News Online website, EASA's approach "gives flexibility to the new industry to mature and innovate, while at the same time ensures the right level of protection for citizens and goods".

Standards set to play a growing role

Currently there are relatively few safety standards that apply to drones specifically, although that is likely to change as governments become more involved in their regulation. However, virtually all drone components, such as batteries or MEMS and other sensors, are currently covered by IEC International Standards.

IEC Technical Committee (TC) 47: Semiconductor devices, and SC (Subcommittee) 47F: Micro electromechanical systems, are responsible for compiling a wide range of International Standards for semiconductor devices used in sensors and MEMS essential to the safe operation of drone flights. These include accelerometers, altimeters, magnetometers (compasses), gyroscopes and pressure sensors.

IEC TC 2: Rotating machinery, prepares International Standards covering specifications for rotating electrical machines and TC 91: Electronics assembly technology, is responsible for standards on electronic assembly technologies including components.

IEC SC 21A: Secondary cells and batteries containing alkaline or other non acid electrolytes, compiles International Standards for batteries used in mobile applications, as well as for large-capacity lithium cells and batteries.

Security and safety issues holding back market growth?

While military applications still dominate the global drone market, commercial and civilian applications are forecast to increase rapidly over the next 10 years. The major drivers identified for the growth of the commercial drones market include increased demand from commercial applications, particularly precision agriculture, and significant technological advancements over the last few years. However, government regulations in some markets, along with security and safety issues, are seen as holding back market growth.

The US-based Teal Group consultancy predicts that the combined market for military and commercial drones will be worth USD 89 billion over the decade from 2015 to 2025. According to a forecast by Business Insider, the market for commercial/civilian drones will grow at a compound annual growth rate (CAGR) of 19% between 2015 and 2020, compared with 5% growth on the military side.