418 research outputs found
UAS for mapping: A product survey on systems and features
No full textIn recent years, unmanned aerial systems (UAS) have attracted tremendous attention from surveyors and other geodata collectors all around the world. Nowadays, UAS equipped with GNSS, IMU and RGB, NIR or TIR cameras and possibly Lidar have evolved into high-potential surveying devices which have now defi nitely passed the stage of ‘toys for boys’. This article focuses on UAS for mapping and 3D modelling and provides a detailed survey in tabular format on the features of the prevailing systems, both fi xed wings and multicopters, available on the market today.OTBArchitecture and The Built Environmen
Preliminary multi-mission UAS design
No full textUnmanned vehicles are important when it comes to performing a desired task in a dangerous or inaccessible environment. Unmanned robots, have been successfully used for many years. More recently, a growing interest in Unmanned Aircraft Systems (UASs) has arisen. In the past few years the development of sensors, microprocessors and propulsion systems resulted in UASs that are smaller, lighter and more capable than ever before. This leads to endurance, efficiency and autonomy levels that exceed the capabilities of manned flight. A large number of successful designs have been created by several universities, commercial companies and research agencies. Due to the wide variety of applications, several configurational concepts have been developed. As a result, most UAS designs are optimized for a dedicated task. In order to perform different tasks, users need to have access to multiple UASs. This means that manufacturers and users have to maintain production and support lines for multiple UASs. The goal of this thesis was to create a preliminary design of a multi-mission UAS by using off-the-shelf systems. This UAS must be able to perform both low and high speed missions. To reach the stated goal a clear overview of all requirements had to be created first. This was followed by extensive market research in order to get an overview of the performance of current UAS designs. This market research was captured in a database. Based on the requirements in combination with the obtained database, all UAS classes and configurational options have been evaluated. The evaluation revealed that a new fixed wing electrical powered mini UAS design may be able to comply with the all UAS requirements. Based on the UAS database, weight estimation relationships for preliminary mini UAS design were derived. These relationships were used for the preliminary UAS performance and weight estimation. After investigating the technical and operational feasibility, the compliance with respect to the requirements was checked. This resulted in a new UAS design point. Subsequently, the UAS design was analyzed in more detail. Optimization of the wing was performed by using a quasi-3D optimizer. This was followed by a tail design that was based on UAS reference data and volume coefficients. The resulting wing and tail design were evaluated by investigating the wing-tail effects and the primary static \& dynamic stability derivatives. This was followed by an evaluation of the material options for the structure. During this evaluation a new manufacturing technique, 3D printing, was tested. Subsequently, the propulsion system design was performed by using a UAV Propulsion Development Kit (UPDK). This UPDK is able to estimate the performance of multiple engine-propeller combinations. Based on the evaluation of the top five combinations, a combination was selected. Finally, the additional UAS subsystems were selected. After the preliminary UAS design was completed, the effectiveness of the design was evaluated. Together with off-the-shelf systems it was possible to create a design that is able to comply with most requirements. The WER for the payload weight was found to be inaccurate. This was caused by the fact that current UASs are equipped with heavier or additional payloads. The WER for the empty weight slightly underestimated the structural weight of the UAS. Overall can be concluded that it is possible to create a preliminary mini UAS design capable of performing both low and high speed missions using off-the-shelf systems.Design, Integration & Operations of Aircraft and RotorcraftAerospace Engineerin
UAS Mapping – Where Is It Heading?
No full textThe use of an unmanned aerial system (UAS) – cameras and Lidar sensors mounted on an unmanned aerial vehicle (UAV or ‘drone’) – to acquire geodata for mapping purposes has evolved beyond infancy and is now rapidly maturing. How will UAS mapping evolve in foreseeable future? To envisage where exactly UAS technology is heading, it is appropriate to start with the big picture before examining the details.GIS Technologi
Third Party Risk Indicators and Their Use in Safety Regulations for UAS Operations
No full textUse of Unmanned Aircraft Systems (UAS) is growing rapidly around the world. Very different types of UAS are used for applications such as aerial photography, inspection, emergency and Urban Air Mobility (UAM), operating in low altitude and urban environment, as well as in high altitude airspace integrated with the conventional air transportation system. As a new airspace user, UAS brings novel safety challenges to the current aviation system. For current aviation the main safety issues concern first and second parties, i.e. lives and property of crew and passengers. In contrast, the main safety concern of UAS operations is third party risk (TPR), i.e. the risk posed to people and properties that have no responsibility for the UAS operation and neither benefit in some way from the UAS operation. In order to ensure the safe operation of UAS, there is a need for an evaluation of safety regulation developments for UAS operations against relevant TPR indicators. The aim of this paper is to identify relevant TPR indicators for UAS operations and to evaluate safety regulations against these TPR indicators. The main finding is that current UAS safety regulations do not consider the accumulation of TPR contributions from many UAS flights per annum over rural or urban populations.Air Transport & Operation
Safety risk posed to persons on the ground by commercial UAS-based services
No full textThe unique capabilities of an Unmanned Aircraft System (UAS) creates opportunities for commercial services. The key question is what is an acceptable level of risk posed to third parties on the ground that have no direct benefit from commercial UAS flights. In literature the common view is that an acceptable level of Third Party Risk (TPR) posed by UAS operations follows from an Equivalent Level Of Safety (ELOS) criterion, which means that per flight hour a UAS should not pose more safety risk to persons on the ground than a commercial aircraft does. However in commercial aviation there are also TPR indicators in use that are directed to accident risk posed by all annual commercial flights to the population around an airport. These population directed indicators find their origin in TPR posed by hazardous installations to its environment. The aim of this paper is to improve the understanding of risk posed to the population by annual UAS-based services through learning from TPR knowledge and regulation for airports and hazardous installations. As main result this paper develops an analytical approach to evaluate the annual risk posed by a commercial UAS-based parcel delivery service in urban and metropolitan areas. The obtained results show that the TPR indicators that stem from hazardous installations and airports provide novel insight regarding TPR of commercial UAS-based service.Air Transport & Operation
Characterizing UAS collision consequences in future UTM
No full textUAS will be integrated into the airspace in the near future, but the risk of UAS collision is not well understood which hampers the development of adequate regulations and standards. As risk has two constituents: frequency and consequence, collision risk analysis of UAS operations in future UTM asks for a quantitative assessment of various types of frequency and consequence. However, prior to studying such quantitative assessment, it is a prerequisite to identify the various types of collisions and consequences. Doing the latter is the objective of this paper. This paper follows a step-wise approach in identifying the various types of collision consequence under a given UTM ConOps, focusing on the very-low-level UAS operations. The first steps address the analysis of the UTM ConOps, rules, and infrastructure considered, and the identification of types of objects and UASs that will operate in the very-low-level UTM system. The follow-up steps are to characterize impact materials by applying zone of impact analysis, followed by analyzing the types of collision consequence. The result is a systematic identification and characterization of types of collision consequences as well as applicable impact materials and conditions that will form the basis for safety risk analysis in follow-on research.Air Transport & OperationsStructural Integrity & CompositesControl & Simulatio
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