Introduction
In order to implement a drone flight over people, the user needs to carry out a number of mandatory approvals both with local authorities and with the operational bodies of the unified air traffic management system, where, among other things, it will be necessary to convince security services that the planned flight will be safe for all who are in the place of its implementation. But, nevertheless, what happens if the drone does fall? Or, even so, — what happens when the DJI Phantom or Mavic Pro collides with a human head? ASSURE experts tried to answer this question by conducting an 18-month study in this direction.
ASSURE (Alliance for System Safety of UAS through Research Excellence) – consists of twenty-three of the world’s leading research institutions and more than one hundred leading industry / government partners. The Alliance has expertise in a wide range of research areas, including: Air Traffic Control Interoperability, Airport UAS Ground Control, Command and Communications, Detection and Prevention, Human Factors, UAS Noise Reduction, UAS Signatures, Drone Pilot Training and Certification, Security low-level control, spectrum control and UAS traffic control.
About the study
ASSURE’s extensive ground impact study was conducted by the Universities of Alabama, Huntsville, and Mississippi, as well as the National Institute for Aeronautical Research at Wichita University, and other alliance partners for possible injuries from drone-to-human collisions. In addition to investigating potential injuries resulting from a drone crash, the researcher also sought to develop a safety testing methodology to provide recommendations to the FAA (US Federal Aviation Administration). The American popular science magazine Popular Mechanics noted that this is the only comprehensive scientific study of its kind in the world.
The results of the study will surprise many. Even though the videos look quite dramatic, the ASSURE researchers found that the small plastic drones were quite flexible and resilient. And drones like the DJI Phantom and Mavic Pro actually absorbed more impact energy, said David Arterburn, ASSURE principal investigator. He also added:
“A common misconception is that every drone is like a stone, and if it collides with a person, it will hurt just like being hit by a stone.”
The ASSURE study was as comprehensive as possible. 512 impact tests were conducted using 16 different types of drones, including popular consumer drones such as the DJI Phantom and Mavic Pro. The researchers also used various types of payloads (batteries, wooden blocks) with weights ranging from 322 grams to 6 kilograms. In addition, full anthropomorphic and simplified impact tests to the head and neck only, as well as a post-mortem impact test are included.
The most common injuries sustained when drones like the DJI Phantom and Mavic Pro collided with a human head were lacerations, cuts and bruises. In one case, there was serious damage to the eye, which is confirmed by ASSURE that the rapidly rotating propellers of the quadcopter can lead to such an injury. As a result, one of the recommendations from ASSURE is the mandatory use of rotor protection.
Safety first
According to David Arterburn, not only is the general public interested in learning more about the risk of injury from drone-to-human collisions, but drone manufacturers themselves are also positively eager for detailed research:
“Companies are really responding to the fact that they now have clear testing standards and methodology in place that can lead to actionable design changes to make their products safer for the public.”
The reason for this is obvious, since many of the successful unmanned services, such as delivering packages, food or medicine, will often be carried out in urban and suburban environments, and, accordingly, will include flying over people, which is prohibited by law in any state.
Drone Design Changes Based on ASSURE Findings
It seems that ASSURE research results are already influencing drone design. Previously, speed and payload were top priorities when designing drones, now the focus has shifted to safety:
“Drone manufacturers can now compare their designs with ASSURE data,” says Arterburn. “These measurements have never been seen before… when you get into the range (in weight) of 3.6 to 4 kilograms, the mass and elasticity of the structure combine to cause more serious injuries.”
Payloads
One of the main findings of the ASSURE study was that payloads tend to have a more rigid design with increased mass, which can lead to more serious injuries:
Due to the nature of the design, many payloads lack the elasticity that aircraft have,” says Arterburn. “Both design and mass play an important role in determining injury potential.”
For example, a battery that is installed on the outside of a drone poses a much greater risk of injury than when it is placed inside the drone. It is likely that in the near future rules will be developed that regulate the type of payloads, as well as the configurations that delivery drones can carry. Parachute safety systems such as ParaZero and Indemnis can also reduce risk significantly, but much more testing of these systems in a controlled environment is required to be sure.
In summary, ASSURE’s head-on-head injury research by ASSURE is one of the first but very important steps towards making safe drone delivery a reality.which in general once again indicates a great future for the UAV commercial niche.