Quadcopters and other sUAVs are becoming increasingly popular among both hobbyists and corporations looking to exploit their potential as delivery devices. Bob Stone discusses the human factors and safety implications of sUAVs and argues in favour of licensing and regulation.

Over the past 18 months or so, we’ve been investigating how best to exploit remotely controlled aerial and land-based vehicles in support of a number of historical site surveys, prior to their reconstruction, using virtual reality techniques.

A number of these sites present us with quite significant challenges in terms of access. Some, such as the old Yelverton Reservoir on the edge of Dartmoor, for example, are surrounded by dense foliage or hidden man-made hazards. Others, such as the 16th Century abandoned manor at Longstone, again on Dartmoor, are cordoned off, awaiting renovation.

We’ve also been using small aerial vehicles – quadcopters and hexacopters – to provide video footage of some of our undergraduate student projects, including a recent successful dive of a remotely operated submersible in a flooded quarry near Tamworth. As our experience has increased, we have become more concerned about the human factors issues surrounding their safe and efficient use.

Small, radio-controlled unmanned air vehicles or sUAVs – vehicles with a mean take-off weight of 7kg or less, including the multi-rotor systems we’ve been using – have attracted considerable attention from members of the press, who have enthusiastically reported on a number of possible non-military applications. For example, in 2013, Amazon announced a plan to launch a new delivery service called Amazon Prime Air which would deploy autonomous quadcopters to deliver orders to customers’ addresses within 30 minutes. Other examples include the restaurant Yo! Sushi, which has used sUAVs, controlled by waiting staff, to deliver meals to tables.

Many commercial applications are true flights of fancy, especially given the limited payload capabilities of most of the commercial off-the-shelf (COTS) products, not to mention their limited endurance in terms of power and all-weather performance.

Of course, those issues may well disappear as the technology evolves, and, judging by the different systems that are now widely available, this evolution is gaining pace. Nevertheless, it has become increasingly apparent that the main limiting factor with these devices is that of the untrained human pilot, and there have certainly been incidents in the recent past which demonstrate the end result of human error, system failure, flying in inappropriate weather conditions and sheer incompetence. In April 2014, a resident of Barrow-in-Furness was prosecuted for having flown a radio-controlled aircraft in restricted airspace over BAE Systems’ nuclear submarine facility. In the USA, a man was questioned by the FBI for crashing a camera-equipped sUAV close to the Bridgeport Harbour Electricity Generating Station.

Instances such as these also worry authorities about the potential for using sUAVs in support of terrorist attacks. In 2011, an al-Qaeda affiliate plan to launch an attack on the Pentagon using an sUAV with an explosives payload was intercepted by the FBI. In 2012, criminals flew a low-cost quadcopter over a Brazilian prison fence to deliver cell phones to the prisoners.

Unfortunately, there have also been numerous reports of injuries, even fatalities, caused by loss of control of an sUAV. The second half of 2013 was particularly bad, with fatalities in Texas, Korea, Brazil and New York.

Of course, there are legislative documents and guidelines covering sUAV flights laid down by aerospace regulators, such as the Civil Aviation Authority (CAA) and Federal Aviation Administration (FAA). The CAA has published guidance that includes a chapter on human factors issues. However, this particular chapter reads very much as if it has been lifted out of a high-level defence human factors standard and, as is often the case with those publications, is far too generic and rigid to cope with a rapidly changing technological scene, let alone the needs of the user of sUAV products. Certainly there are a number of relevant issues highlighted within the chapter, including references to degraded pilot situation awareness, pilot risk perception and strategies for effective reversion to manual control for systems that support some degree of in-flight autonomy. However, the style of wording and absence of illustrated examples do little to emphasise the very real dangers of flying under direct-view or first-person view (FPV) conditions to the increasing population of casual or research sUAV users.

Having now experimented with a number of sUAV solutions, we find ourselves in strong agreement with those calling for regulations to be strengthened. Indeed, we have recently produced our own standard operating procedures to go some way to fill in the gaps. Over the past 12 months alone, our hexacopter has evolved from a 2kg to 4kg payload capacity, enabling our students to conduct research into a wide range of new payload options, from new automatic vision and non-visual sensors, to head-slaved FPV camera pan-and-tilt units feeding stereoscopic video data to a head-mounted display. The addition of a gimbal-stabilised camera platform certainly supports the generation of very impressive video footage when undertaking FPV flying, but, on occasions, even our experienced pilot has been “drawn in” by the stunning picture quality, only to be alerted, just in time, by the appearance of the sUAV propeller blades in the field of view as the vehicle becomes progressively unstable.

It is certainly possible to undertake flight and ground training courses for flying fixed and rotary wing sUAVs that culminate in basic competency qualifications. For example, a small number of organisations offer the National UAS Certificate for Small Unmanned Aircraft and the Remote Pilot Qualification - Small Unmanned Aircraft, both of which are recognised by the CAA as evidence of pilot competence. However, these courses tend to be focused on those wanting to use UAVs for professional or commercial work, as opposed to the hobbyist or academic researcher. It is clear that, as the stories of injuries, fatalities, property damage, invasion of privacy, trespass and airspace incursion increase, the situation has to change, even though any change will, without doubt, be very unpopular with many hobbyists and retailers. Some COTS sUAV developers, for example, are already developing firmware modifications to help prevent incursions into restricted airspace. This is certainly a promising start, even though it may not be met with enthusiasm from some sUAV users. However, we believe that much more needs to be done, including ensuring that every sUAV sold needs to be registered and marked, perhaps even chipped, in some way so as to uniquely identify the platform with its owner. There is no doubt that this will be difficult to enforce, especially as 3D printing technologies are increasingly being used to ‘manufacture’ replacement components.

We also believe that some form of licence should be held by sUAV users, granted only after passing a basic competence assessment. This could be a test similar to those used to train and test decision-making and observational skills for driving students. sUAV simulator packages already exist, but many fall short of teaching and evaluating the essential skills and awareness necessary for safe sUAV deployments. With early attention to human-centred design and a subsequent focus on delivering appropriate sensory and behavioural fidelity, simulators would be more than capable of testing reaction times, manual control stability, appropriate decision-making for flights, pilot distraction effects, and so on. Such tests would not replace the more professional courses but would help to ensure the growing community of COTS sUAV users use their product safely and responsibly.

Some may complain that these measures are over the top and totally unnecessary for something that is, after all, just a smaller version of a radio-controlled helicopter. However, just type “quadcopter injuries” into Google Images and make your own mind up…

By Professor Bob Stone, Director of the Human Interface Technologies Team at the University of Birmingham.

This article first appeared in Issue 530 of The Ergonomist, August 2014.

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