scholarly journals Stability-based motion planning for a modular morphing wing

2021 ◽  
Author(s):  
Michael C. F. Kwong
Keyword(s):  
Selection Process ◽  
Static Stability ◽  
Path Selection ◽  
Critical Parameters ◽  
Morphing Wing ◽  
Wing Geometry ◽  
Variable Geometry Truss ◽  
Different Levels ◽  
Longitudinal Static Stability

Aircraft wing geometry morphing is a technology that has seen recent interest due to demand for aircraft to improve aerodynamic performance for fuel saving. One proposed idea to alter wing geometry is by a modular morphing wing designed through a discretization method and constructed using variable geometry truss mechanisms (VGTM). For each morphing maneuver, there are sixteen possible actuation paths for each VGTM module, and thus offering a three module morphing wing to have a total of 16(to the power of 3) permutations of actuation paths for one morphing maneuver. Focused on longitudinal static stability, critical parameters and aircraft stability theory, this thesis proposes a method to find an optimal actuation path for a designated maneuver iteratively. A case study of a three module morphing wing demonstrated the actuation path selection process. Numerically, different actuation paths had different levels of longitudinal static stability; these paths were drawn in CATIA and were visually verified.

scholarly journals Stability-based motion planning for a modular morphing wing

2021 ◽  
Author(s):  
Michael C. F. Kwong
Keyword(s):  
Selection Process ◽  
Static Stability ◽  
Path Selection ◽  
Critical Parameters ◽  
Morphing Wing ◽  
Wing Geometry ◽  
Variable Geometry Truss ◽  
Different Levels ◽  
Longitudinal Static Stability

Aircraft wing geometry morphing is a technology that has seen recent interest due to demand for aircraft to improve aerodynamic performance for fuel saving. One proposed idea to alter wing geometry is by a modular morphing wing designed through a discretization method and constructed using variable geometry truss mechanisms (VGTM). For each morphing maneuver, there are sixteen possible actuation paths for each VGTM module, and thus offering a three module morphing wing to have a total of 16(to the power of 3) permutations of actuation paths for one morphing maneuver. Focused on longitudinal static stability, critical parameters and aircraft stability theory, this thesis proposes a method to find an optimal actuation path for a designated maneuver iteratively. A case study of a three module morphing wing demonstrated the actuation path selection process. Numerically, different actuation paths had different levels of longitudinal static stability; these paths were drawn in CATIA and were visually verified.

scholarly journals Non-Destructive Tests for Damage Evaluation of Stone Columns: The Case Study of Sacro Monte in Ghiffa (Italy)

2020 ◽  
Vol 10 (8) ◽  
pp. 2673 ◽  
Author(s):  
Alessandro Grazzini ◽  
Sara Fasana ◽  
Marco Zerbinatti ◽  
Giuseppe Lacidogna
Keyword(s):  
Static Stability ◽  
Diagnostic Techniques ◽  
Stone Columns ◽  
Damage Evaluation ◽  
Structural Elements ◽  
Heritage Sites ◽  
The Impact ◽  
Non Destructive ◽  
Different Levels

The Italian Sacri Monti are heritage sites with some unique characteristics; they are a successful symbiosis between nature and art and are unconfined structures, therefore always being accessible but exposed to atmospheric agents, with many relevant consequences with regard to conservation problems. The paper discusses some aspects related to the application of non-destructive techniques (NDT) for the interpretation of degradation phenomena occurring in stone structural elements. Ultrasonic and impact tests were used to evaluate the structural properties of the stone columns in the Via Crucis portico, within the monumental complex of the Sacro Monte in Ghiffa (Piedmont, Italy), in order to determine their conditions of maintenance and to evaluate the portico static stability. Ultrasonic tests made it possible to obtain the value of the dynamic elastic modulus, which was variable at different points of the columns due to the diversified level of material damage. The impact test, performed with an instrumented hammer in the same points of the ultrasonic test, enables, by comparison, a deeper knowledge of the surface resistance of damaged columns. These results are the first step in a research path that will require further laboratory tests to better calibrate the diagnostic techniques applied to different levels of damage to surface materials.

scholarly journals Digital Twin for Designing and Reconfiguring Human–Robot Collaborative Assembly Lines

2021 ◽  
Vol 11 (10) ◽  
pp. 4620
Author(s):  
Niki Kousi ◽  
Christos Gkournelos ◽  
Sotiris Aivaliotis ◽  
Konstantinos Lotsaris ◽  
Angelos Christos Bavelos ◽  
...  
Keyword(s):  
Production System ◽  
Assembly Lines ◽  
Flexible Assembly ◽  
Digital Twin ◽  
Collaborative Assembly ◽  
Geometrical Information ◽  
Line Level ◽  
Dual Arm ◽  
Different Levels

This paper discusses a digital twin-based approach for designing and redesigning flexible assembly systems. The digital twin allows modeling the parameters of the production system at different levels including assembly process, production station, and line level. The approach allows dynamically updating the digital twin in runtime, synthesizing data from multiple 2D–3D sensors in order to have up-to-date information about the actual production process. The model integrates both geometrical information and semantics. The model is used in combination with an artificial intelligence logic in order to derive alternative configurations of the production system. The overall approach is discussed with the help of a case study coming from the automotive industry. The case study introduces a production system integrating humans and autonomous mobile dual arm workers.

Numerical study of geometric morphing wings of the 1303 UCAV

2021 ◽  
pp. 1-17
Author(s):  
B. Nugroho ◽  
J. Brett ◽  
B.T. Bleckly ◽  
R.C. Chin
Keyword(s):  
Flight Control ◽  
Numerical Study ◽  
Aerodynamic Characteristics ◽  
Morphing Wing ◽  
Rolling Moment ◽  
Wide Range ◽  
Morphing Wings ◽  
Wing Geometry ◽  
Lift And Drag ◽  
Wing Morphing

ABSTRACT Unmanned Combat Aerial Vehicles (UCAVs) are believed by many to be the future of aerial strike/reconnaissance capability. This belief led to the design of the UCAV 1303 by Boeing Phantom Works and the US Airforce Lab in the late 1990s. Because UCAV 1303 is expected to take on a wide range of mission roles that are risky for human pilots, it needs to be highly adaptable. Geometric morphing can provide such adaptability and allow the UCAV 1303 to optimise its physical feature mid-flight to increase the lift-to-drag ratio, manoeuvrability, cruise distance, flight control, etc. This capability is extremely beneficial since it will enable the UCAV to reconcile conflicting mission requirements (e.g. loiter and dash within the same mission). In this study, we conduct several modifications to the wing geometry of UCAV 1303 via Computational Fluid Dynamics (CFD) to analyse its aerodynamic characteristics produced by a range of different wing geometric morphs. Here we look into two specific geometric morphing wings: linear twists on one of the wings and linear twists at both wings (wash-in and washout). A baseline CFD of the UCAV 1303 without any wing morphing is validated against published wind tunnel data, before proceeding to simulate morphing wing configurations. The results show that geometric morphing wing influences the UCAV-1303 aerodynamic characteristics significantly, improving the coefficient of lift and drag, pitching moment and rolling moment.

scholarly journals Evaluation of the energy consumption of container diesel trucks in a container terminal: A case study at Klaipeda port

2021 ◽  
Vol 104 (3) ◽  
pp. 003685042110355
Author(s):  
Tomas Eglynas ◽  
Sergej Jakovlev ◽  
Valdas Jankunas ◽  
Rimantas Didziokas ◽  
Jolanta Januteniene ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Dynamic Properties ◽  
Container Terminal ◽  
Superposition Principle ◽  
Critical Parameters ◽  
Container Transportation ◽  
Industrial Emissions ◽  
Transportation Process ◽  
Diesel Trucks

Introduction: In the paper, we examine the energy consumption efficiency of specialized container diesel trucks engaged in container transportation at a seaport terminal. Objectives: Using the container terminal at Klaipėda in Lithuania as the background for the research, we produced an improved energy consumption model for measuring the theoretical energy consumption and regeneration of diesel trucks at the terminal and provide a comparative analysis. Methods: We created a mathematical model which describes the instantaneous energy consumption of the diesel trucks, taking into account their dynamic properties and the overall geometry of their routes—“Ship-Truck-Stack-Ship”—using the superposition principle. We investigated other critical parameters relevant to the model and provide a statistical evaluation of the transportation process using data from a case study of Klaipėda port, where we collected measurements of container transportation parameters using georeferenced movement detection and logs from wireless equipment positioned on the diesel-powered container trucks. Results: The modeling results showed that an instantaneous evaluation of energy consumption can reveal areas in the container transportation process which have the highest energy loss and require the introduction of new management and process control initiatives to address the regulations which are designed to decrease harmful industrial emissions and encourage novel technologies and thereby increase the eco-friendliness of existing systems. Conclusion: Based on the research results, the article can provide a reference for the estimation of diesel truck efficiency in seaport terminal operations.

scholarly journals The Importance of Environmental Factors in the Planning of Container Terminals: The Case Study of the Port of Augusta

2021 ◽  
Vol 11 (5) ◽  
pp. 2153
Author(s):  
Nadia Giuffrida ◽  
Maja Stojaković ◽  
Elen Twrdy ◽  
Matteo Ignaccolo
Keyword(s):  
Environmental Impact ◽  
Container Terminal ◽  
Decision Support Tool ◽  
Container Terminals ◽  
Mitigation Measures ◽  
Support Tool ◽  
Clean Environment ◽  
Different Levels

Container terminals are the main hubs of the global supply chain but, conversely, they play an important role in energy consumption, environmental pollution and even climate change due to carbon emissions. Assessing the environmental impact of this type of port terminal and choosing appropriate mitigation measures is essential to pursue the goals related to a clean environment and ensuring a good quality of life of the inhabitants of port cities. In this paper the authors present a Terminal Decision Support Tool (TDST) for the development of a container terminal that considers both operation efficiency and environmental impacts. The TDST provides environmental impact mitigation measures based on different levels of evolution of the port’s container traffic. An application of the TDST is conducted on the Port of Augusta (Italy), a port that is planning infrastructural interventions in coming years in order to gain a new role as a reference point for container traffic in the Mediterranean.

unrechtliche peinliche schmehung oder dem gemeinen nutz nuetzlich?Eine Fallstudie zur Normenkonkurrenz im Schmähschriftprozess des 16. Jahrhunderts

2020 ◽  
Vol 25 (1) ◽  
pp. 135-149
Author(s):  
Jan Siegemund
Keyword(s):  
Early Modern ◽  
Common Good ◽  
Public Places ◽  
Legal Norms ◽  
The Public ◽  
The Common ◽  
The Public Sphere ◽  
The City ◽  
Different Levels

AbstractLibel played an important and extraordinary role in early modern conflict culture. The article discusses their functions and the way they were assessed in court. The case study illustrates argumentative spaces and different levels of normative references in libel trials in 16th century electoral Saxony. In 1569, Andreas Langener – in consequence of a long stagnating private conflict – posted several libels against the nobleman Tham Pflugk in different public places in the city of Dresden. Consequently, he was arrested and charged with ‘libelling’. Depending on the reference to conflicting social and legal norms, he had therefore been either threatened with corporal punishment including his execution, or rewarded with laudations. In this case, the act of libelling could be seen as slander, but also as a service to the community, which Langener had informed about potentially harmful transgression of norms. While the common good was the highest maxim, different and sometimes conflicting legally protected interests had to be discussed. The situational decision depended on whether the articulated charges where true and relevant for the public, on the invective language, and especially on the quality and size of the public sphere reached by the libel.

scholarly journals Natural resource abundance and eminent domain: A case study from Africa

2012 ◽  
Vol 27 (4) ◽  
pp. 319-325 ◽  
Author(s):  
Franklin Obeng-Odoom
Keyword(s):  
West Africa ◽  
Natural Resource ◽  
Analytical Framework ◽  
Eminent Domain ◽  
Resource Abundance ◽  
Local Impacts ◽  
Compulsory Purchase ◽  
Oil City ◽  
Different Levels

This Viewpoint article draws on the doctrine of eminent domain (or compulsory purchase) as an analytical framework to analyse the regional and local impacts of a new source of oil. Sekondi-Takoradi, an oil city located in Ghana, West Africa, is used as a case study to explore the differentiated experiences of local people. The article shows that, although there are complex distributional issues that require different levels of compensation and betterment to be assessed and paid for, it is unlikely that they will, in fact, even be considered.

scholarly journals A Dispatching-Fuzzy AHP-TOPSIS Model for Scheduling Flexible Job-Shop Systems in Industry 4.0 Context

2021 ◽  
Vol 11 (11) ◽  
pp. 5107
Author(s):  
Miguel Ortíz-Barrios ◽  
Antonella Petrillo ◽  
Fabio De Felice ◽  
Natalia Jaramillo-Rueda ◽  
Genett Jiménez-Delgado ◽  
...  
Keyword(s):  
Job Shop ◽  
Selection Process ◽  
Fuzzy Ahp ◽  
Flexible Job Shop ◽  
Criteria Weights ◽  
Dispatching Algorithm ◽  
Scheduling Method ◽  
Hard Problems ◽  
Fourth Step

Scheduling flexible job-shop systems (FJSS) has become a major challenge for different smart factories due to the high complexity involved in NP-hard problems and the constant need to satisfy customers in real time. A key aspect to be addressed in this particular aim is the adoption of a multi-criteria approach incorporating the current dynamics of smart FJSS. Thus, this paper proposes an integrated and enhanced method of a dispatching algorithm based on fuzzy AHP (FAHP) and TOPSIS. Initially, the two first steps of the dispatching algorithm (identification of eligible operations and machine selection) were implemented. The FAHP and TOPSIS methods were then integrated to underpin the multi-criteria operation selection process. In particular, FAHP was used to calculate the criteria weights under uncertainty, and TOPSIS was later applied to rank the eligible operations. As the fourth step of dispatching the algorithm, the operation with the highest priority was scheduled together with its initial and final time. A case study from the smart apparel industry was employed to validate the effectiveness of the proposed approach. The results evidenced that our approach outperformed the current company’s scheduling method by a median lateness of 3.86 days while prioritizing high-throughput products for earlier delivery.

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