Reece A. Clothier

Risk Perception and the Public Acceptance of Drones

Unmanned aircraft, or drones, are a rapidly emerging sector of the aviation industry. There has been limited substantive research, however, into the public perception and acceptance of drones. This article presents the results from two surveys of the Australian public designed to investigate (1) whether the public perceive drones to be riskier than existing manned aviation, (2) whether the terminology used to describe the technology influences public perception, and (3) what the broader concerns are that may influence public acceptance of the technology. We find that the Australian public currently hold a relatively neutral attitude toward drones. Respondents did not consider the technology to be overly unsafe, risky, beneficial, or threatening. Drones are largely viewed as being of comparable risk to that of existing manned aviation. Furthermore, terminology had a minimal effect on the perception of the risks or acceptability of the technology. The neutral response is likely due to a lack of knowledge about the technology, which was also identified as the most prevalent public concern as opposed to the risks associated with its use. Privacy, military use, and misuse (e.g., terrorism) were also significant public concerns. The results suggest that society is yet to form an opinion of drones. As public knowledge increases, the current position is likely to change. Industry communication and media coverage will likely influence the ultimate position adopted by the public, which can be difficult to change once established.

The Smart Skies project

The Smart Skies project is an ambitious and world-leading research endeavor exploring the development of key enabling technologies, which support the efficient utilization of airspace by manned and unmanned airspace users. This provides a programmatic description of the research and development of: an automated separation management system; a mobile aircraft tracking system; and aircraft-based sense-and-ad technologies. A summary of the results from a series of real-world flight testing campaigns is also presented.

Fuzzy Multi-Objective Mission Flight Planning in Unmanned Aerial Systems

This paper discusses the development of a multi-objective mission flight planning algorithm for unmanned aerial system (UAS) operations within the National Airspace System (NAS). Existing methods for multi-objective planning are largely confined to two dimensional searches and/or acyclic graphs in deterministic environments; many are computationally infeasible for large state spaces. In this paper, a multi-objective fuzzy logic decision maker is used to augment the D* Lite graph search algorithm in finding a near optimal path. This not only enables evaluation and trade-off between multiple objectives when choosing a path in three dimensional space, but also allows for the modelling of data uncertainty. A case study scenario is developed to illustrate the performance of a number of different algorithms. It is shown that a fuzzy multi-objective mission flight planner provides a viable method for embedding human expert knowledge in a computationally feasible algorithm

An innovative navigation and guidance system for small unmanned aircraft using low-cost sensors

Purpose – The purpose of this paper is to design a compact, light and relatively inexpensive navigation and guidance system capable of providing the required navigation performance (RNP) in all phases of flight of small unmanned aircrafts (UA), with a special focus on precision approach and landing. Design/methodology/approach – Two multi-sensor architectures for navigation and guidance of small UA are proposed and compared in this paper. These architectures are based, respectively, on a standard extended Kalman filter (EKF) approach and a more advanced unscented Kalman filter (UKF) approach for data fusion of global navigation satellite systems (GNSS), micro-electro-mechanical system (MEMS)-based inertial measurement unit (IMU) and vision-based navigation (VBN) sensors. Findings – The EKF-based VBN-IMU-GNSS-aircraft dynamics model (ADM) (VIGA) system and the UKF-based system (VIGA+) performances are compared in a small UA integration scheme (i.e. AEROSONDE UA platform) exploring a representative cross-se...

Pilotless aircraft: the horseless carriage of the twenty‐first century?

This paper identifies recurring issues in the regulation of new technologies through an historical review of the risk management of automobiles in the 1800s. Parallels are drawn between the regulation of early automobiles and that of the regulation of Unmanned Aircraft Systems (UASs) today. It is found that many of the regulatory challenges facing UASs are analogous to those which faced the automobile industry more than a century and half ago and that the need for informed and objective decision making in policy development is reinforced. A systems engineering approach, based on general systems theory and decision‐based design principles, is then proposed as a means for improving the objectivity, transparency and rationality in the risk management decision making process. An example risk management decision making scenario is given within the context of a small UAS operating over a populated area. The results obtained from this case study illustrate how even simple analysis can support the decision making process and highlights some of the potential challenges in the regulatory approach currently applied to UASs.

Reverse Engineering of a Fixed Wing Unmanned Aircraft 6-DoF Model for Navigation and Guidance Applications

A method for deriving the parameters of a six-degree-of-freedom (6-DoF) aircraft dynamics model by adopting reverse engineering techniques is presented. The novelty of the paper is the adaption of the 6-DoF Aircraft Dynamics Model (ADM) as a virtual sensor integrated in a low-cost navigation and guidance system designed for small Unmanned Aircraft (UA). The mass and aerodynamic properties of the JAVELIN UA are determined with the aid of an accurate 3D scanning and CAD processing. For qualitatively assessing the calculated ADM, a trajectory with high dynamics is simulated for the JAVELIN UA and compared with that of a published 6-DoF model of the AEROSONDE UA. Additionally, to confirm the validity of the approach, reverse engineering procedures are applied to a published CAD model of the AEROSONDE UA aiding to the calculation of the associated 6-DoF model parameters. A spiral descent trajectory is generated using both the published and calculated parameters of the AEROSONDE UA and a comparative analysis is performed that validates the methodology. The accurate knowledge of the ADM is then utilized in the development of a virtual sensor to augment the UA navigation and guidance system in case of primary navigation sensor outages.

Development of a Template Safety Case for Unmanned Aircraft Operations Over Populous Areas

One of the primary hazards associated with the operation of Unmanned Aircraft (UA) is the controlled or uncontrolled impact of the UA with terrain or objects on the terrain (e.g., people or structures). National Aviation Authorities (NAAs) have the responsibility of ensuring that the risks associated with this hazard are managed to an acceptable level. The NAA can mandate a range of technical (e.g., design standards) and operational (e.g., restrictions on flight) regulatory requirements. However, work to develop these regulations for UA is ongoing. Underpinning this rule-making process is a safety case showing how the regulatory requirements put in place ensure that the UA operation is acceptably safe for the given application and environment. There is no accepted framework for structuring or assessing the safety case for UA operations over populous areas, or for assessing the effectiveness of the wide range of potential technical and operational measures that can be potentially employed as part of a safety case. This paper presents a Barrier Bow Tie (BBT) model as a suitable template for the development and assessment of safety cases for UA operations over populous areas. The components of the BBT model and its application to UA operations over populous areas are presented. A case study is used to highlight the desirable features of the BBT model. The BBT model provides a systematic means for classifying and assessing proposed risk controls (the points of regulation) and how these controls contribute (in isolation and in combination) towards a reduction in risk.

An Evaluation of Multi-Rotor Unmanned Aircraft as Flying Wind Sensors

This paper examines the possibility of using a Multi-Rotor Unmanned Aircraft System (MUAS) for atmospheric flow measurements around a tall building. This novel sensing approach is proposed, whereby we attempt to determine the oncoming flow velocity magnitude and direction from measurements of the power required by each of the MUAS rotors. Extensive wind-tunnel testing was completed to determine the power required by the fore and aft rotor-pairs at varying flow velocities and directions. The results show that it is possible to map between rotor power consumption and the oncoming flow vectors, however, a unique and accurate mapping is only possible over a very small region of the measurement space. Thus, it is concluded that the practical use of this sensing method is limited. Examination of power consumption curves also revealed that the conditions under which a Vortex Ring State (VRS) develops for small MUAS. The characteristics of VRS development are similar to those of full-size helicopters, indicating that the VRS is Reynolds number independent. The reduction in power consumption due to the presence of updraft flows of various magnitudes was also quantified, indicating that significant endurance improvements of MUAS are possible and can be achieved when operating windward of large buildings.

Towards Autonomous MAV Soaring in Cities: CFD Simulation, EFD Measurement and Flight Trials

MAVs are increasingly being used in complex terrains, such as cities, despite challenges from the highly turbulent flow fields. We investigate the flow around a nominally cuboid building of height 40m both computationally and experimentally in a 1/100th scale wind-tunnel test. A relatively new computational technique, Improved Delayed Detached Eddy Simulation (IDDES), was used for computing the time-varying flow around the building and surrounding domain. The atmospheric boundary layer velocity and turbulent intensity profiles were replicated at the inlet boundary of the computational domain and wind tunnel. The spatial flow field from the CFD was investigated for locating suitable areas of lift, in order to see if soaring flight would be feasible. Good agreement was found with the wind-tunnel results. Flight trials of a small flying wing aircraft were conducted from the roof demonstrating the possibility of keeping aloft with no conventional power system. Soaring was achieved under piloted control and autonomously. The CFD results proved useful in locating the best lift areas and provided insights into path planning.

Mutual Recognition of National Military Airworthiness Authorities: A Streamlined Assessment Process

The Air and Space Interoperability Council (ASIC) has adopted the European Defence Agency (EDA) process for interregulatory military airworthiness authority recognition. However, there are gaps in the application of this process to nations outside of the European Union. This paper proposes a model that can effectively map diverse technical airworthiness regulatory frameworks. This model, referred to as the Product-Behaviour-Process (PBP) Bow-Tie model, provides the systematic structure needed to represent and compare regulatory frameworks. The PBP Bow-Tie model identifies key points of difference that need to be addressed, during inter-agency recognition between the two regulatory authorities. With the intention to adopt global use of the EDA process, the proposed PBP Bow-Tie model can be used as a basis for the successful recognition of regulatory frameworks outside of the European Union. Iris plots produced from the implementation of this model are presented, and proposed as a suitable means of illustrating the outcome of an assessment, and of supporting the comparisons of results. A comparative analysis of the Australian Defence Force and New Zealand Defence Force airworthiness regulatory frameworks is used as a case study. The case study clearly illustrates the effectiveness of the model in discerning regulatory framework differences; moreover, it has offered an opportunity to explore the limitations of the Iris plot.