149544 research outputs found
Sort by
Drone Teleoperation Interfaces: Challanges and Opportunities with XR Integration
No full textDrones are piloted remotely through teleoperation interfaces. These interfaces typically employ 2D displays, which can limit Situation Awareness (SA) due to narrow field-of-view (FoV) and lack of depth perception. Extended Reality (XR) has potential to enhance these systems by providing 3D environments that improve spatial understanding and expand FoV. However, designing drone teleoperation interfaces requires a thorough understanding of remote pilot’s SA needs and usability challenges to ensure safety and facilitate decision-making. This makes a user-centered design (UCD) approach essential. To this end, we present findings from qualitative interviews with (n=8) professional drone pilots, designed to (1) identify key challenges in current teleoperation interfaces, and based on these challenges, (2) provide an outlook on how XR could address these issues. This work aims to guide future research and design of XR-based teleoperation interfaces to improve SA and safety in drone operations
Long‑term monitoring of barometric altitude measurement performance using the example of a research aircraft
Get PDFThe barometric flight altitude is the decisive variable for the vertical separation of aircraft in the airspace. At present, no
aircraft operator is able to independently monitor the proper function of barometric altimetry in flight. In this paper, a method
is presented for long-term monitoring of barometric altimetry system performance only by means of flight data and model
output data from a numerical weather prediction model. This method enables aircraft operators to independently monitor
barometric altimetry system performance of their aircraft fleet. Aberrant aircraft can be identified earlier and can be taken out
of service for inspection measures more predictable, or inspected as part of already planned maintenance measures. Already
existing flight data from DLR’s research aircraft Airbus A320-232 ATRA from 2014 to 2020 were used to determine the
long-term behavior of the barometric altitude measurement performance using this method. During two of the flights under
consideration, the aircraft was equipped with a trailing cone system, which is currently considered the most accurate way for
measuring ambient pressure airborne. Hence, these flights were used as a reference. The summary of the implementation,
evaluation, and main results is presented in this paper, starting with a brief introduction to numerical weather prediction
models and their model output data. Details on the air data system and position measurement of the research aircraft are
addressed as well as prerequisites regarding selection of parameters. Both reference and distance flights are described during
which the analyzed flight data were gathered. Data pre-processing and evaluation are explained comprehensively. Finally,
obtained results and findings are assessed and discussed with regard to the applicability of the method and future research
work. In summary, application of the presented method to a research aircraft has shown good agreement compared to an
established method such as the trailing cone system
Verification of Two-Way Time Transfer Accuracy Through a Closed-Loop Topology of Inter-Satellite and Satellite-Ground Optical Links
Get PDFThe exploitation of Optical Inter-Satellite Links (OISLs) has the potential to provide significant benefits to GNSSs, offering clock synchronization via highly accurate time transfer, precise ranging, robustness against jamming and spoofing, high data rates, and freedom from signal frequency regulations. As with any new technology, it is crucial to conduct in-space experiments to demonstrate the capabilities of OISLs before widespread adoption.
In this work, we present preliminary analyses of an in-orbit demonstrator concept, which is being designed under the name Optical Synchronized Time And Ranging (OpSTAR). It involves two satellites in a trailing configuration, each equipped with two laser terminals. On the ground, two co-located Optical Ground Stations (OGSs) are operated. Whenever both satellites are simultaneously visible from the OGSs, an OISL and two additional Optical Satellite-to-Ground Links (OSGLs) are established, forming a closed "measurement loop" between the two satellites and the two ground stations.
We present a functional model for OISL and OSGL pseudorange observables. A cross-link clock observable is formed by differencing two one-way pseudoranges, from which a relative clock offset estimate is obtained. First, we analyze how modelling errors on differential delays in Two-Way Time Transfer (TWTT) -- relativistic effects, atmospheric delays, hardware delays, and satellite dynamics during the exchange -- impact the estimation accuracy. Next, we study the impact of individual error contributions to the overall zero-sum chain of clock offset estimates across the closed-loop. Results show that errors due to mis-modeling of relativistic effects, satellite dynamics and clock instability are negligible, while hardware and atmospheric delays require accurate calibrations to achieve TWTT at picosecond-level accuracy
Dynamic Modeling of an Internal Combustion Engine in Open-Modelica
No full textThis project aims to develop a four-stroke spark-ignition (SI) internal combustion engine model using OpenModelica. The model is designed and implemented through programming to analyze engine performance and assess the impact of key parameters, including bore size, stroke length, and compression ratio, on engine power. Built upon the Otto cycle, the model simulates engine behavior using thermodynamic principles and fundamental engine equations. This study also examines how variations in structural parameters influence overall engine efficiency and performance. The findings reveal that changes in engine design parameters significantly affect power output. The developed model serves as a valuable tool for performance analysis under various operating conditions, contributing to the optimization and advancement of more efficient internal combustion engines
SOKI - Schleusungsoptimierung mit Hilfe künstlicher Intelligenz
No full textIm Rahmen des Projekts SOKI entwickelt die BAW zusammen mit dem DLR e. V. ein Verfahren zur Optimierung des
Verkehrsflusses durch Schleusenketten mittels maschinellen Lernens. Im Pilotbetrieb soll das entwickelte Verfahren
zunächst simulativ untersucht und anschließend auf dem
WDK getestet werden
The perception of aircraft noise and its impact among children
No full textAlthough children are considered vulnerable to the effects of noise, research seldom addresses their subjective experience directly, with parental evaluations often used as proxies. In a field study at Cologne/Bonn Airport, we explored the perception of aircraft noise and its chronic impacts among 51 children aged 8 to 10 years. Separate interviews were conducted with both children and their parents. The children provided self-reports, while parents assessed the noise-related effects on themselves as well as on their children. The interviews focused on chronic annoyance and disturbance of daily activities, including sleep disruption attributed to aircraft noise, as well as factors thought to influence noise perception, such as noise sensitivity. When comparing self-reports, children generally described themselves as less annoyed by aircraft noise and less sensitive to noise overall compared to parental assessments. According to children’s reports, the activities most frequently disturbed were indoor passive communication, the ability to fall asleep, and concentrating indoors. Discrepancies between children’s self-reports and parental assessments were particularly evident regarding sleep disturbances; parents tended to underestimate children’s difficulty to fall asleep due to noise. These findings emphasize the importance of recording children’s experience in noise effect studies rather than relying solely on parental assessments
GCxGC-Based iso-Alkane Subgrouping for Enhanced Compositional Analysis of Sustainable Aviation Fuels
No full textTo evaluate sustainable aviation fuels (SAF) and other novel jet fuels, nontargeted comprehensive analysis by two-dimensional gas chromatography (GCxGC) is commonly utilized. The obtained results are necessary for subsequent model-based prescreening applications. The uncertainty of the respective property predictions is dependent on the degree of compositional detail as some properties (e.g., flash point, freezing point) are strongly influenced by structural molecular features. In the absence of sufficient structural reference data, individual identification from reference databases is usually not possible. Consequently, the results obtained from GCxGC are generally categorized by the carbon number and group type. To obtain greater details on the isomeric structure distribution of fuels, the iso-alkane family was further investigated. Therefore, a multilinear regression model for iso-alkane retention indices (RI) was constructed from molecular descriptors. Subsequently, the combined database from measurement and literature was extended by prediction to complete the data for all possible 42,900 branched isomers within the jet range (C7-C17). The isomeric structures were sorted into subgroups by their respective retention behavior, thereby correlating with the present number of molecular branches. The structural subgroup information was then used to create branching indicators to quantify and compare the subgroup distributions of different fuels. It was evident that isomeric distributions were unique to the respective samples. The new detail of composition will aid the characterization and differentiation of different fuels and present further potential for fuel assessment
CARIOQA Quantum Pathfinder Mission for space weather research
No full textThe CARIOQA Quantum Pathfinder missions aims at demonstrating a quantum technology-based accelerometer in space as a precursor for a later deployment onboard a satellite gravimetry mission. A dedicated satellite will be launched for the Pathfinder mission in 2030 to raise the technology level of the required technologies for applications on operational missions. The Phase A study to investigate the feasibility of this mission has just concluded and the project will continue into Phase B. In this presentation, we discuss the relationship between available models of the atmospheric conditions in low Earth orbit and the instrument and satellite design as well as the impact on the development of requirements to fulfil the mission objectives. In addition to the demonstration of the functionality of the quantum accelerometer, the Pathfinder mission will also provide accelerometer measurements in low Earth orbit for the expected mission lifetime of three years. As a scientific objective of the mission, this dataset will be used to derive parameters like thermosphere density or atmospheric crosswinds
FAGEM: Paulus-Preis zum neunten Mal verliehen
No full textDie schweizerischen Organisatoren der diesjährigen D-A-CH-Konferenz in Bern hatten für die Schlussveranstaltung am 27. Juni Preisverleihungen vorgesehen. Der DMG-Fachausschuss für Geschichte der Meteorologie (FAGEM) nutzte gerne diese Möglichkeit, um gemäß seiner Statuten zum neunten Mal seit 2001 den Paulus-Preis zu verleihen für die beste nominierte einschlägige Arbeit, die seit der vorhergehenden Konferenz erschienen war. Einzelheiten zu Preis und Stifter finden sich auf den DMG-Webseiten und im Nachruf auf Rudolf Paulus. In seiner Laudatio gab der Berichterstatter am Ende von einleitenden Bemerkungen in der dreifachen Alliteration „Paulus-Preis für Brönnimann!“ den aktuellen Preisträger bekannt