More than Toys
There might be a perception that non state actor use of commercial unmanned systems means they are unsophisticated.
It might even be tempting to think of small commercial UAS as not far removed from toys.
Whilst there are many toy-like devices, there are as many that bear no relationship to a toy whatsoever, professional users in the inspection, survey, filmmaking, agriculture, archaeology, emergency response and journalism sectors are driving innovation and improvements in all sorts of interesting directions.
These are just a few examples, likely to be out of date as soon as they are written, and focussed on multi rotor vertical lift types.
Most drones are relatively fragile, open rotors and lightweight construction make them prone to damage from minor collisions and rough landings. Aftermarket modification kits can provide rotor guards and specialist crash proof designs have also emerged for use in crevasse exploration and search, stop sniggering at the back.
The Flyability Gimbal has also been proposed as a suitable design for search and rescue in urban environments. The Vantage Robotics Snap uses four rotors with integral guards, safety and robustness feature heavily in their marketing materials.
It is easy to envisage lightweight blade guards being mandatory in some markets.
Most devices are specified to carry a camera payload but there have been many instances of organisations wanting to use them for high-value parcel delivery (Amazon, DHL etc.). Drug delivery in remote locations in Africa has also been mooted as a possible use for small UAS. This has resulted in an increase in interest in improving payloads.
Most commercially available and common devices are still in the ‘couple of kilogram’ range but those used for cinematography and survey at the professional end of the spectrum are now commonly available with payloads in excess of 10kg.
The real Achilles heel of consumer/prosumer types is their endurance, typically, only 20-30 minutes.
This makes them of less use for persistent ISTAR but then again, the ultra-expensive PD-100 Black Hornet Nano UAV from Prox-Dynamics and Marlborough Communications that is in service with the British Army only has a flight time of 20-25 minutes. Military systems have been developed that utilise fuel cells but the civilian market has been slower to catch up due to cost.
Although battery technology is always improving, one solution currently being explored by a number of manufacturers is hydrogen fuel cells.
Intelligent Energy, from Loughborough, have developed a hydrogen fuel cell that can extend flight duration to several hours. EnergyOR from Canada, likewise, in fact, EnergyOR have recently announced the H2Quad that has a 1kg payload and 2-hour endurance.
If communications or autonomy allows, this puts the device into the 80-100km range.
If size is not an issue, larger UAS can carry larger payloads and batteries, 10kg and 1-hour endurance, for example, is not uncommon for the larger devices.
Many systems are available with mission planning software that allows the operator to pre-programme flight paths and waypoints to reduce workload and reliance on skilled operators. Many of these are open source, available on software repositories and ‘app stores’.
Third party mission planning and flight control software are also increasingly available from specialist vendors.
Flight control software is available to circle around an object, move on a virtual wire, object following, full systems monitoring, and flight planning with waypoints, station keeping, and automatic return to launch point, camera control, automatic data export and autonomous search.
The images below show screen captures from a number of flight control applications.
For use in areas where availability or visibility of a GPS signal may be in doubt, underneath a bridge or in the shadow of a large building, for example, precise positioning would normally be a problem.
Inertial positioning is one option but for other locations, GPS can be augmented with Differential GPS that makes use of publicly available beacons (Trinity House in the UK for example) or using a system like Local Positioning System (LPS) from Novadem.
Attacking GPS is often seen as a critical weakness, but only if the system actually uses it.
High definition day/night sensors are a given but thermal imaging, LIDAR and Multi-Spectral Sensors are also available to commercial users. UAV Vision manufactures a gimballed EO/IR sensor weighing less than 700g that can stream video imagery at a pixel resolution of 720×576 and IR at 640×480. Like all responsible vendors, they won’t sell to just anyone but this is still commercial technology. LIDAR scanners are used for collision detection and 3D mapping.
The Drones for Good Competition has resulted in a number of academic programmes such as the one shown below for mine detection, from Bristol University.
Tamron have recently introduced a camera module for small UAS that includes onboard optical stabilisation, together with full HD output and FLIR have a number of packaged IR systems
On-board image processing devices from vendors such as Headwall allow multiple sensors and data inputs to be fused.
Common control stations and those that can be used to control multiple platforms are available, and how about a smartwatch control system!
Control systems typically require line of sight and this naturally reduces utility, waypoint navigation can be used and payload systems are exploring alternatives to GPS and Wi-Fi. Although regulatory conditions normally specify a line of sight as being the distance limit there are some professional applications where this is being exceeded.
The video below shows a non-line of sight record flight from a DJI Phantom
Mesh network technologies have also started to appear in unmanned systems for a robust and non-line of sight communications.
This is one of the main focus areas of current research for obvious reasons, either for low speed or high-speed operations. Laser, ultrasonic and even synthetic vision using a Microsoft Kinect sensor have all been implemented with the objective of allowing them to fly in close formation, inside buildings and urban areas. The videos below show systems using on-board automatic obstacle avoidance, human operators are not making the decisions.
Swarming technology is also in receipt of a great deal of interest, indeed, the MoD Centre for Defence Enterprise is funding a competition called ‘Many Drones Make Light Work‘ that will explore how swarming technology can be used in support of defence missions
Although this is clearly a defence funded activity, there are many parallel in industry and academia.
Manufacturers have also started to specialise in niche markets, mapping, survey and mining for example. Two market leaders are senseFly and QuestAV. Both can produce hyper accurate geo-referenced digital imagery using autonomous unmanned aircraft. The post-flight analysis is carried out to add reference points, ground information and stitch the imagery together into an ortho-mosaic image.
It can then be exported in a number of formats suitable for inclusion in mapping and GIS systems, whether they be publicly accessible through a UN On-Site Operations Coordination Centre (OSOCC) and MapBox.
QuestAV have recently introduced a system specifically for the marine environment called QuestAV Aqua (imaginative I know!).
The rapidly growing and commercialising sport of ‘drone racing’ will also further drive innovation, especially in endurance, speed and obstacle avoidance.
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