UAVs: The new trend in acquiring geospatial data through remote sensing

UAVs: The new trend in acquiring geospatial data through remote sensing

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Drones and UAVs for aerial mapping and inspection - In this example you see the inspection of electric transmission tower

UAVs are very likely to displace conventional ways of acquiring remotely sensed geospatial data, and the entire industry is ready to jump onto this bandwagon. The first to do so already have a head start.

USE OF DRONES

– Hurricane Hunting: Drones can be used to track tropical storm data through a storm’s long evolution without risking lives.

– 3D Mapping: Small, lightweight drones can survey landscapes with thousands of digital images that can be stitched together into 3D maps.

– Protecting Wildlife: World Wildlife Foundation (WWF) and governments in many nations are already using drones to protect wildlife.

– Farming: Precision agriculture uses technology to monitor fields. Drones can help by identifying exactly where such resources are needed and delivering them.

– Search and rescue: SAR missions are time consuming, expensive, and often dangerous. The use of well-equipped drones is increasing for SAR and could soon become a standard way to cover large areas of inaccessible terrain, even at night.

The use of unmanned aerial systems (UAS), or UAVs, or drones as they are more popularly known, is associated almost always with surveillance and war. As the demand for timely, accurate, high-resolution and hyperspectral data for mapping, exploring, investigating and monitoring natural resources as well as assets on terra firma increases, the pilotless flying machines are switching hardware. The ‘hellfire’ missiles are being replaced by imaging and non-imaging sensors. UAVs, as a platform for collecting imagery data, are the in thing and a niche in geospatial technologies today. Reductions in the cost of hardware required to fabricate and maintain UAVs and the advances in sensor and camera technologies, along with the availability of light and long-lasting power packs, have made the mass production of UAVs possible.

The very fact that this flying data collection platform can be managed by a single person and carried in the field has drastically reduced the geospatial industry’s dependence on high resolution satellite imagery. However, the data collected by the imaging sensors on board the UAVs has boosted the remote sensing industry, especially the software required for the processing and extraction of information from the digital data acquired by the sensors and cameras. “In most cases, this new data stream should be incorporated fairly smoothly in the current workflows. New survey applications that would replace ground measurements could potentially even facilitate the workflow,” says Denis Cormier, Research Leader, FPInnovations, which is amongst the world’s largest private, non-profit research centres working in forest research.Fo example, Cormier thinks mill inventory applications could present workflow challenges if handled directly by the mill. However, the inventory firms that are currently doing the ground survey of chip piles for them could adjust their workflow more easily and potentially provide volume estimations with similar, or even better, levels of accuracy for a competitive cost. “As we see it, the only challenge in inventorying with UAV, like any other aerial system, could be clear weather conditions for imaging to meet specific target dates of quarterly accounting/auditing processes,” he adds.

UAV manufacturers primarily fall into two categories — those who create military-spec killing machines, and those who design and develop UAVs for civilian uses. The former have nothing to worry about from the regulations that currently plague this booming geospatial industry. The latter are being seriously affected by the indecisiveness of the regulators. If quick steps are not taken, they may lose interest and motivation for further investment, design and development.

The driving factors

In the long-term it is “Moore’s Law, advances in digital radio communication, and the commercial opening of GPS” which will drive the demand for UAVs, says Dave Litwiller, Vice President (Strategy), Aeryon Labs. More recently, the advent of small-size and low-cost MEMS gyroscopes and accelerometers to create sufficiently small and robust autopilot technology have been the driving forces. Further, the widespread appreciation of the speed, flexibility and fast return on investment from the use of UAVs in commercial, law enforcement and military applications is driving mainstream adoption.

In the long-term it is “Moore’s Law, advances in digital radio communication, and the commercial opening of GPS” which will drive the demand for UAVs, says Dave Litwiller, Vice President (Strategy), Aeryon Labs. More recently, the advent of small-size and low-cost MEMS gyroscopes and accelerometers to create sufficiently small and robust autopilot technology have been the driving forces. Further, the widespread appreciation of the speed, flexibility and fast return on investment from the use of UAVs in commercial, law enforcement and military applications is driving mainstream adoption.

“There are two key forces at work here. The first is regulations, which of course impact UAS applications significantly. The second is that autonomous systems enable UAVs to complete a job without needing human input, which in turn creates efficiency and accuracy for a broad spectrum of industries,” points out Kareem Shehata, Lead Engineer (Autonomous Systems), Clearpath Robotics.

“UAS can be used as gap-fillers for missed satellite opportunities due to cloud cover,” says Tamme van der Wal, Partner at Aero Vision and Coordinator of the European UNIFARM project. UAS can also be enhancers with the higher resolutions (for instance for sharpening or unmixing of reflectance data). A combination of sources seems the best strategy to optimise RoI.

The ‘UAV market’ is a pretty new (but not young). It is only in the past few years that UAVs have been able to lift heavy payloads of 2-3 kg and fly for a significant time to perform missions, according to Joerg Lamprecht, Founder & CEO, Aibotix. Affordable software to control and process the collected information has been the key, feels Todd Steiner, Marketing Director for the Imaging Business Area, Geospatial Division, Trimble.

“The arrival of the smart, miniaturised autopilot technology and LiPo (Lithium-Ion Polymer) batteries played a significant role in driving the mini drone market forward, allowing us to create intelligent automated drones with flight times of up to 45 or even 50 minutes depending on weather conditions,” says Jean-Christophe Zuffrey, Founder and CEO, senseFly.

This is revolutionary, as earlier, before conducting any survey, aircraft equipped with high sensors were deployed. But now people can create their own aerial imagery, which can be used for various purposes like surveying, stockpile volume calculation, etc. The significant drivers for this industry are the batteries, which have increased the fly time, the payloads, and high-resolution sensors which can generate imagery of up to 1 mm or 1 cm resolution, adds Lamprecht.

The availability of reliable low-cost autopilots and navigation systems has made UAS an accessible solution for many users, believes Charles Rihner, Vice President of the Topcon GeoPositioning Solutions Group. Navigation systems like GPS and GLONASS allow for accurate georeferencing of images and auto-navigation at no cost to the user. Some UAS manufacturers like Topcon offer the capability to track GPS+GLONASS signals, providing more satellite availability and better positional accuracy at no additional cost.

A small entrepreneur’s world

Rihner firmly believes that at the grassroots level, the UAS market has actually been driven by small teams building autonomously flying vehicles. In their search for commercial applications, they have found several niches, like mapping, in which their technology can be successfully applied. The mapping industry, always looking for more efficient ways to do business, has jumped on this.

At present, it appears to be a level-playing field for the big and small. The market is young and the buyers are really the choosers of this convincing yet not totally feasible (due to policy constraints) technology and methodology, and the SMEs are raking in some moolah.

Lamprecht thinks the industry needs the small players to evangelise the market. “They are creative, innovative and they bring lots of different ideas into the field,” he says, at the same time calling for some regulations — certification of the product, pilot and mission. It is worth mentioning that Lamprecht’s Aibotix was acquired by Hexagon, recently.

There is a sizeable number of DIY (Do it Yourself) developers who are also entering the UAV market. With considerably lower overheads and almost no budgets or strategies for marketing, these small players are surprisingly a force to reckon with. Their cost undercut impacts the big players, adding to the tough competition for sales. Zuffrey thinks he is not really sure if this really affects the big players market, since the target customers of such DIY drone kits and automated professional solutions are very different.

Most professional users recognise that the cost of ownership is much more than the initial cost of the kit to assemble a UAV, points out Litwiller. Moreover, there is an elevated cost of failure in mission-critical and high value applications. “Our customers demand a significantly higher level of product capability, training, service and support than the make-it-yourself tier of the industry can generally deliver,” he adds.

For their users — professionals such as land surveyors, GIS professionals, precision farmers, and mining engineers — drones are simply a tool for data collection. However, given the ease of use and usability of drones, many quickly come to love using the technology. Users of this technology are not hobbyists or drone enthusiasts. “They are simply looking to do their jobs as efficiently and as safely as possible. This also means they appreciate being able to deal with a company that offers quality technical support and, through its dealer network, an increasing number of local maintenance centres,” says Litwiller.

Considering the massive R&D budgets that the big players have, and their technological edge, Rihner believes that such environment is standard for any new technology market and the big players are now starting to show their advantages of technology integration (for example, high-accuracy RTK) and will be able to play the volume advantage card as the market grows.

Evolution in imaging technology

A UAV technically becomes a UAS due to the payload, which in the present context are cameras, sensors and detectors — both imaging and non-imaging. The hardware development has been rapid and sensors with very high resolution (both spatial and radiometric) are in the market. The parallel development of software to accept high data throughput and analyse and deliver usable products is in place.

“The rapid pace of development of visible wavelength imaging technology for high volume consumer and professional markets has been remarkable over the past many years, as well as the reduction in cost of thermal imagers,” says Litwiller. Multi-spectral and hyper-spectral imaging technologies have also been propelled by investments in other industries which have directly contributed to the high rate of advancements of sensor technology. LiDAR, as well as various types of chemical sensors, are undergoing rapid cost-performance-size improvements. The challenge is the size and weight of the sensors, and, as Steiner adds, the data quality and output are not the issue anymore.

The eBee drone platform from senseFly comes with a choice of several high-quality sensors from RGB, near-infrared, red-edge, multispectral and even thermal payloads which are well below the 700-750 gram range.

Between increasing payload capacity and decreasing sensor size and capabilities, sensors are keeping pace as new ones keep coming with newer capabilities every year. “What we have found at Clearpath is that customers often need help choosing which sensors and configurations will work best for their application, which is a sign of a healthy ecosystem,” says Shehata.

The industry by and large thinks the development of appropriate sensors as a payload on a UAS is developing. “We are mainly interested in radiometers (ranging from visible to thermal) but when possible and miniaturised, microwave sensors can be very interesting too,” says van der Wal. Many companies are now trying to optimise their sensors in terms of weight, robustness and power consumption.

However, Cormier feels the development of appropriate sensors is still very spotty across platforms. “Miniaturisation is now even making LiDAR and multispectral cameras usable with many small UAVs. However, standardisation would also be very beneficial here,” he adds. UAS platforms adapted to any sensors tend to need an ‘expert’ to operate them while platforms for general users tend to have proprietary sensors.

“When we started our UAS research efforts we were limited to fewer choices of sensors (predominantly video based cameras). Over the years we have been able to use digital cameras with limited spectral bands,” says Balaji Ramachandran, Associate Professor, Head and Geomatics Programme Coordinator, Nicholls State University. The Geomatics Programme is working in collaboration with the Marine and Environmental Biology Programme to look into applying small UAS for assessing and mapping the coastal habitat of Isle Dernieres Barrier Island Refuge (IDBIR) ecosystem. The project is currently working on integrating light-weighed multispectral and LiDAR sensors for the UX5 airframe for mapping.

This research integrates knowledge from geospatial science to address the gaps that currently exist in modeling dynamic coastal ecosystems, and their restoration and management after a catastrophic event such as the Deep Water Horizon Oil Spill. This research will assess the usefulness and cost effectiveness of small-UAS (sUAS) for long term monitoring and protecting of the fragile coastal ecological systems at IDBIR.

“We are also looking into different chemical and biological sensors as payloads for other disaster management applications. As the UAS technology matures, we will have specific sensor payloads for specific applications. It will be a matter of interchanging the sensor for a particular application,” says Ramachandran, who is also working closely with the US Army Corps of Engineers (USACE) and offshore petroleum industries in using UAS technology for monitoring river control structures, levees, and rig flares on deep-water oil and gas production platforms.

Counting the beans

Currently available UAVs from the big players cost upward of $50,000 and the sensors are a separate cost. It is evident that the price tag for a UAS from a big brand would cost anywhere above $50,000, not inclusive of the personnel and logistics. Does maintaining such a high sales price gain anything? Apparently, it does. “Yes, advanced technology is available with the higher-end UAS accompanied with backend training and support,” says Rihner. In most cases, big players are offering more optional integration. Topcon, for example, offers integrated GNSS RTK, which is a game changer. In addition, they have the infrastructure to offer additional services to support the mapping professional. Steiner too feels that UAS products range greatly in price, data outputs, and the overall solution they provide to customers; this variation creates a vibrant and competitive marketplace, with plenty of choices for customers.

These strategies are not necessarily the best or the correct ones. There are an increasing number of small-UAS (sUAS) developers, many of who have started as RC hobby aircraft manufacturers and have evolved and modified their machines to carry larger payloads along with software in the form of free of-the-shelf or customised apps running on handheld devices. Zuffrey, therefore, feels that this type of cost does not apply to all the UAS manufacturers, and his drones sell for considerably less than this — with one camera payload and two professional software packages (pre- and post-flight) included as standard. However, for professional clients such as land surveyors or managers of large-scale farming operations, such costs are not usually prohibitive. The costs of surveying instruments such as laser scanners and total stations, for example, regularly run into the tens and even hundreds of thousands of dollars, as do the costs of the latest precision agriculture tractors and combine harvesters, and the return on investment from a sUAS is almost immediate.

However, Cormier thinks the technology is still not fully reliable and users are developing experience on the spot, which can lead to mechanical problems that will need full commitment from the manufacturers to make the business of UAS data provider viable. He feels the cost of parts is a major obstacle for maintaining a sustainable UAS data provider business and it is almost impossible for the users to address the issue of high cost. “Absence of standards makes the users hostage to a single manufacturer. When selecting a platform, the user needs to select a manufacturer with a known record of reliable after sale service to run an efficient operation. This is not obvious in an industry that deals with rapid transformations and quick obsolescence,” he adds.

The policy issues

The lack of categorical policy from the global national aviation authorities with regard to the permissions for flying UAVs is hurting business and investments. This issue is being addressed by lobbying and in some  cases educating policymakers. SenseFly is a member of the Small UAV Coalition, which Zuffrey explains, advocates for law and policy changes to permit the operation of small UAVs, with varying degrees of autonomy for commercial, consumer, recreational, and philanthropic purposes.

Currently, every nation has its own regulations and this kind of holds the market down, feels Lamprecht. This is good for bigger players because they can get certified in any country, but when the smaller ones want to export their products, it becomes really hard.

Unfortunately, many UAV manufacturers follow a ‘wait and watch’ policy, which may be affordable for the big players, but not for small manufacturers who cannot sustain in such an environment. Some of them have recently petitioned the US FAA for exemptions to fly their mapping drones, for surveying and agricultural purposes, based on existing rules for flying model aircraft. Zuffrey is confident that this is an innovative approach since the petition is fully supported by the Academy of Model Aeronautics (AMA) and the AUVSI. Most importantly, if approved, this permission would allow companies working in these fields to operate mapping drones immediately, without requiring them to each obtain their own FAA exemption. Litwiller, from Aeryon Labs, responds to this prevailing environment by working well within the prevailing regulatory frameworks, rather than trying to time or rely upon changes in regulations.

Very few countries have a proper policy and Shehata feels that his company, Clearpath Robotics, is fortunate to be operating in Canada. The SFOC (special flight operating certificate) process is consistent across the country and allows operators to make a case for the safe use of their vehicles to get their missions done. With Canada leading the way in these types of policies, there are now other jurisdictions that are starting to open up their rules to allow the commercial use of UAVs. “Many people want to see it happening faster, but these things [regulations] take time,” warns van der Wal. “It helps to overcome the hype I guess, as the safety norms help in a shakeout and consolidation of the market.”

Anusuya Datta,
Executive Editor, Geospatial World Magazine

Dr Hrishikesh Samant,
Editor – Mining (Honorary) Geospatial Media and Communications