Enhanced pose adjustment system for wing-box assembly in large aircraft manufacturing

2021 ◽  
pp. 1-28
Author(s):  
Biao Mei ◽  
Yongtai Yang ◽  
Weidong Zhu
Keyword(s):  
Large Scale ◽  
Physical Simulation ◽  
Complex Structure ◽  
Aviation Industry ◽  
Aircraft Manufacturing ◽  
Pose Alignment ◽  
Adjustment System ◽  
Best Fit ◽  
Large Aircraft ◽  
Wing Box

Abstract Strict quality requirements in aircraft manufacturing demand high accuracy concerning pose alignments of aircraft structures. However, even though a pose adjustment system does pass the accuracy verification, the pose of the large complex structure has difficulty in smoothly and efficiently converging on the desired pose in large aircraft assembly. To solve this problem, we developed a pose adjustment system enhanced by integrating physical simulation for the wing-box assembly of a large aircraft. First, the development of the pose adjustment system, which is the base of the digital pose alignment of a large aircraft’s outer wing panel, is demonstrated. Then, the pose alignment principles of duplex and multiple assembly objects based on the best-fit strategy are successively explored. After that, the contributor analysis is conducted for nonideal pose alignment, in which the influences of thermal and gravity deformations on the pose alignment are discussed. Finally, a physical simulation-assisted pose alignment method considering multisource errors, which uses the Finite Element Analysis (FEA) to integrate temperature fluctuation and gravity field effects, is developed. Compared with a conventional digital pose adjustment system driven by the classical best-fit, the deviations of the Key Characteristic Points (KCPs) significantly decreased despite the impacts of thermal and gravity deformations. The developed pose alignment system has been applied to large aircraft wing-box assembly in Aviation Industry Corporation of China, Ltd. It provides an improved understanding of the pose alignment of large-scale complex structures.

The carbon star R Sculptoris sheds its skin

2018 ◽  
Vol 14 (S343) ◽  
pp. 546-547
Author(s):  
Markus Wittkowski
Keyword(s):  
Large Scale ◽  
Complex Structure ◽  
Carbon Star ◽  
Bright Spot ◽  
Average Intensity ◽  
Fundamental Parameters ◽  
Near Ir ◽  
Low Mass ◽  
Best Fit ◽  
Shock Fronts

AbstractWe describe near-IR H-band VLTI-PIONIER aperture synthesis images of the carbon AGB star R Sculptoris with an angular resolution of 2.5 mas. The data show a stellar disc of diameter ∼ 9 mas exhibiting a complex substructure including one dominant bright spot with a peak intensity of 40% to 60% above the average intensity. We interpret the complex structure as caused by giant convection cells, resulting in large-scale shock fronts, and their effects on clumpy molecule and dust formation seen against the photosphere at distances of 2–3 stellar radii. Moreover, we derive fundamental parameters of R Scl, which match evolutionary tracks of initial mass 1.5 ± 0.5 M⊙. Our visibility data are best fit by a dynamic model without a wind, which may point to problems with current wind models at low mass-loss rates.

Health monitoring sensor placement optimization based on initial sensor layout using improved partheno-genetic algorithm

2020 ◽  
pp. 136943322094719
Author(s):  
Xianrong Qin ◽  
Pengming Zhan ◽  
Chuanqiang Yu ◽  
Qing Zhang ◽  
Yuantao Sun
Keyword(s):  
Genetic Algorithm ◽  
Health Monitoring ◽  
Large Scale ◽  
Complex Structure ◽  
Sensor Placement ◽  
Placement Problem ◽  
Optimal Sensor Placement ◽  
Placement Optimization ◽  
Sensor Placement Optimization ◽  
Sensor Locations

Optimal sensor placement is an important component of a reliability structural health monitoring system for a large-scale complex structure. However, the current research mainly focuses on optimizing sensor placement problem for structures without any initial sensor layout. In some cases, the experienced engineers will first determine the key position of whole structure must place sensors, that is, initial sensor layout. Moreover, current genetic algorithm or partheno-genetic algorithm will change the position of the initial sensor locations in the iterative process, so it is unadaptable for optimal sensor placement problem based on initial sensor layout. In this article, an optimal sensor placement method based on initial sensor layout using improved partheno-genetic algorithm is proposed. First, some improved genetic operations of partheno-genetic algorithm for sensor placement optimization with initial sensor layout are presented, such as segmented swap, reverse and insert operator to avoid the change of initial sensor locations. Then, the objective function for optimal sensor placement problem is presented based on modal assurance criterion, modal energy criterion, and sensor placement cost. At last, the effectiveness and reliability of the proposed method are validated by a numerical example of a quayside container crane. Furthermore, the sensor placement result with the proposed method is better than that with effective independence method without initial sensor layout and the traditional partheno-genetic algorithm.

scholarly journals Uzbekistan’s Development under the Leadership of Various Political Reforms: The Case of Air Transport Industry

2021 ◽  
Vol 15 (1) ◽  
pp. 160-169
Author(s):  
Sarvar Khalikov ◽  
Wei Liu ◽  
Madina Turaeva ◽  
Liliya Achilova
Keyword(s):  
Soviet Union ◽  
Large Scale ◽  
Russian Language ◽  
Air Transport ◽  
Transport Sector ◽  
Aviation Industry ◽  
Policy Reforms ◽  
Political Reforms ◽  
Air Transport Industry ◽  
New Perspective

The First President of Uzbekistan, Islam Karimov, continued to isolate the country for many years even after the collapse of the Soviet Union in 1991, which in turn worsened all the strategic sectors in the country, especially the aviation market and tourism industries. However, in the period 2017-2018, the skyrocket in the number of tourists, from 2.69 million to 5.34 million, became possible due to the coming of Shavkat Mirziyoyev to power as the new President. But the lack of air connectivity kept reducing aspiration of traveling from non-CIS countries. To solve the issue, the new President Mirziyoyev’s large-scale policy reforms concerned the air transport sector, too. The main objective of the study is to compare the development of the country under the leadership of various political reforms using the aviation industry of Uzbekistan as an example. To achieve the purposes, the authors examine reciprocal action/influence between airlines, airports and government. In addition, a significant amount of data was collected from Russian-language sources to enrich the content. Even though the paper was written before the COVID-19 pandemic, the authors' research is still important to nudge readers into a new perspective.

scholarly journals Methodical foundations of the preventing monitoring of aviation industry economic agents

2020 ◽  
pp. 9-14
Author(s):  
Iryna NIENNO ◽  
Yurii HRINCHENKO
Keyword(s):  
Sustainable Development ◽  
Customer Value ◽  
Rating Scale ◽  
Aviation Industry ◽  
Logical Scheme ◽  
The Sustainable Development ◽  
Economic Agents ◽  
Aircraft Manufacturing ◽  
Seat Comfort ◽  
Technological Modernization

The article formulates the methodical grounds for preventive monitoring of service and production components of economic agents of aviation industry. The structural-logical scheme for monitoring by quantitative parameters and by consumers’ feedback was proposed. The preventive monitoring is a valuable tool to recognize the interaction between government and industry’s goals considering sustainable development. The goal of the article is to develop methodological grounds for preventive testing of economic agents of the aviation industry, which will include assessment parameters, assessment scale, role instructions and transparency of results. The preventive tasting of airport operations is based on travelers’ experience on: queuing, airport shopping, terminal cleanliness, terminal seating, food beverages, Wi-Fi connectivity, terminal signs, airport staff, sentiment. The preventive testing for airline experience includes: value for money, cabin staff, seat comfort, food comfort, inflight entertainment, ground service, Wi-Fi connectivity, sentiment. The preventive testing for aircraft onboard experience assesses: legroom, seat recline, seat width, aisle space, viewing TV, power supply, seat storage, sentiment. The preventive testing for aircraft manufacturing and maintenance analyses: design, full-cycle manufacturing, warrantee, post-warrantee repair, consolidated designing, manufacturing and maintenance process, leasing, technological modernization, licensing. The article provides the comprehensive system for a preventive monitoring based on customer value, which fixes the key parameters for improvements of the operation of the economic agents of the industry. The conclusion of the research reasons the application of quality assessment based on consumer value created by industry’s agents for a preventive monitoring along financial evaluation and bankruptcy probability for the assessment of the sustainable development of the industry. The perspective of the further research may focus on formulating signaling system for government instruments and on detailing the rating scale for the industry’s agents, based on benchmarking practice.

Ultrasonic Nondestructive Testing for In-Line Monitoring of Wire-Arc Additive Manufacturing (WAAM)

2020 ◽  
Author(s):  
Md Shahjahan Hossain ◽  
Hossein Taheri ◽  
Niraj Pudasaini ◽  
Alexander Reichenbach ◽  
Bishal Silwal
Keyword(s):  
Quality Assurance ◽  
Additive Manufacturing ◽  
Nondestructive Testing ◽  
Large Scale ◽  
Gas Flow ◽  
Complex Structure ◽  
Process Condition ◽  
Process Conditions ◽  
Ultrasonic Signals ◽  
Wire Arc Additive Manufacturing

Abstract The applications for metal additive manufacturing (AM) are expanding. Powder-bed, powder-fed, and wire-fed AM are the different kinds of AM technologies based on the feeding material. Wire-Arc AM (WAAM) is a wire-fed technique that has the potential to fabricate large-scale three-dimensional objects. In WAAM, a metallic wire is continuously fed to the deposition location and is melted by an arc-welding power source. As the applications for WAAM expands, the quality assurance of the parts becomes a major concern. Nondestructive testing (NDT) of AM parts is necessary for quality assurance and inspection of these materials. The conventional method of inspection is to perform testing on the finished parts. There are several limitations encountered when using conventional methods of NDT for as-built AM parts due to surface conditions and complex structure. In-situ process monitoring based on the ultrasound technology is proposed for WAAM material inspection during the manufacturing process. Ultrasonic inline monitoring techniques have the advantages of providing valuable information about the process and parts quality. Ultrasonic technique was used to detect the process condition deviations from the normal. A fixture developed by the authors holds an ultrasonic sensor under the build platform and aligned with the center of the base plate. Ultrasonic signals were measured for different process conditions by varying the current and gas flow rate. Features (indicators) from the radio frequency (RF) signal were used to evaluate the difference in signal clusters to identify and classify different build conditions. Results show that the indicator values of the ultrasonic signals in the region of interest (ROI) changes with different process conditions and can be used to classify them.

Oceanography of the New Zealand subantarctic region

2021 ◽  
Author(s):  
◽  
Aitana Forcén-Vázquez
Keyword(s):  
New Zealand ◽  
Interannual Variability ◽  
Water Column ◽  
Large Scale ◽  
Southern Oscillation ◽  
Complex Structure ◽  
Positive Trend ◽  
Intermediate Water ◽  
Subantarctic Region

<p>Subantarctic New Zealand is an oceanographycally dynamic region with the Subtropical Front (STF) to the north and the Subantarctic Front (SAF) to the south. This thesis investigates the ocean structure of the Campbell Plateau and the surrounding New Zealand subantarctic, including the spatial, seasonal, interannual and longer term variability over the ocean properties, and their connection to atmospheric variability using a combination of in-situ oceanographic measurements and remote sensing data.  The spatial and seasonal oceanographic structure in the New Zealand subantarctic region was investigated by analysing ten high resolution Conductivity Temperature and Depth (CTD) datasets, sampled during oceanographic cruises from May 1998 to February 2013. Position of fronts, water mass structure and changes over the seasons show a complex structure around the Campbell Plateau combining the influence of subtropical and subantarctic waters.  The spatial and interannual variability on the Campbell Plateau was described by analysing approximately 70 low resolution CTD profiles collected each year in December between 2002 and 2009. Conservative temperature and absolute salinity profiles reveal high variability in the upper 200m of the water column and a homogeneous water column from 200 to 600m depth. Temperature variability of about 0.7 °C, on occasions between consecutive years, is observed down to 900m depth. The presence of Subantarctic Mode Water (SAMW) on the Campbell Plateau is confirmed and Antarctic Intermediate Water (AAIW) reported for the first time in the deeper regions around the edges of the plateau.  Long-term trends and variability over the Campbell Plateau were investigated by analysing satellite derived Sea Level Anomalies (SLA) and Sea Surface Temperature (SST) time series. Links to large scale atmospheric processes are also explored through correlation with the Southern Oscillation Index (SOI) and Southern Annular Mode (SAM). SST shows a strong seasonality and interannual variability which is linked to local winds, but no significant trend is found. The SLA over the Campbell Plateau has increased at a rate of 5.2 cm decade⁻¹ in the last two decades. The strong positive trend in SLA appears to be a combination of the response of the ocean to wind stress curl (Ekman pumping), thermal expansion and ocean mass redistribution via advection amongst others.  These results suggest that the variability on the Campbell Plateau is influenced by the interaction of the STF and the SAF. The STF influence reaches the limit of the SAF over the western Campbell Plateau and the SAF influence extends all around the plateau. Results also suggest different connections between the plateau with the surrounding oceans, e.g., along the northern edge with the Bounty Trough and via the southwest edge with the SAF. A significant correlation with SOI and little correlation with SAM suggest a stronger response to tropically driven processes in the long-term variability on the Campbell Plateau.  The results of this thesis provide a new definitive assessment of the circulation, water masses and variability of the Campbell Plateau on mean, annual, and interannual time scales which will support research in other disciplines such as palaeoceanography, fisheries management and climate.</p>

Forming Canonical 8D Data Clouds to Explore the Transient Dynamics of Physical Stiffened Plates: A Machine Learning Approach for Complex Mechanical Structures

2020 ◽  
Author(s):  
Ioannis T. Georgiou
Keyword(s):  
Machine Learning ◽  
Large Scale ◽  
Complex Structure ◽  
Spatial Dimension ◽  
Physical Structure ◽  
Transient Dynamics ◽  
Alloy Plate ◽  
Considerable Uncertainty ◽  
Acceleration Signal ◽  
The Impact

Abstract This work presents a data-driven explorative study of the physics of the dynamics of a physical structure of complicated geometry. The geometric complexity of the physical system renders the typical single sensor acceleration signal quite complicated for a physics interpretation. We need the spatial dimension to resolve the single sensory signal over its entire time horizon. Thus we are introducing the spatial dimension by the canonical eight-dimensional data cloud (Canonical 8D-Data Cloud) concept to build methods to explore the impact-induced free dynamics of physical complex mechanical structures. The complex structure in this study is a large scale aluminum alloy plate stiffened by a frame made of T-section beams. The Canonical 8D-Data Cloud is identified with the simultaneous acceleration measurements by eight piezoelectric sensors equally spaced and attached on the periphery of a circular material curve drawn on the uniform surface of the stiffened plate. The Data Cloud approach leads to a systematic exploration-discovery-quantification of uncertainty in this physical complex structure. It is found that considerable uncertainty is stemming from the sensitivity of transient dynamics on the parameters of space-time localized force pulses, the latter being used as a means to diagnose the presence of structural anomalies. The Data Cloud approach leads to aspects of machine learning such as reduced dynamics analytics of big sensory data by means of heavenly machine-assisted computations to carry out the unparalleled data reduction analysis enabled by the Advanced Proper Orthogonal Decomposition Transform. Emphasized is the connection between the characteristic geometric features of high-dimensional datasets as a whole, the Data Cloud, and the modal physics of the dynamics.

scholarly journals Problems of mineral raw material losses of quality and quantity management in developing of large-scale complex-structure deposits.

2018 ◽  
Vol 56 ◽  
pp. 04003
Author(s):  
Sergei Tkach
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Complex Structure ◽  
Raw Material ◽  
Qualitative And Quantitative ◽  
Mineral Raw Material ◽  
Regulatory Documents ◽  
Geological Conditions ◽  
High Degree ◽  
Very High

The article deals with the problems of mineral raw material losses of quality and quantity management in developing of large-scale complex-structure and composition deposits of solid minerals. It is shown that a very high degree of mining and geological conditions variability in time and space for the development of mining units is typical for such deposits. This significantly complicates the qualitative and quantitative operating losses setting and accounting of mineral raw materials during its extraction in the framework of existing general and industry regulatory documents. Conceptual principles for face-by-face operational setting of losses and impoverishment of minerals for the conditions of bulk mining of complex-structure deposits with the formation of gross mining flow with economically feasible and specified level of quality (the content of commercial and harmful components) are stated. These principles generally do not contradict effective instructions main provisions and are made to minimize the total operating losses during the processing of several mine sections (faces).

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