scholarly journals EVALUATION OF VISION-BASED LOCALIZATION AND MAPPING TECHNIQUES IN A SUBSEA METROLOGY SCENARIO

2019 ◽  
Vol XLII-2/W10 ◽  
pp. 127-134
Author(s):  
F. Menna ◽  
A. Torresani ◽  
E. Nocerino ◽  
M. M. Nawaf ◽  
J. Seinturier ◽  
...  
Keyword(s):  
Measured Data ◽  
Remotely Operated Vehicle ◽  
The Core ◽  
Localization And Mapping ◽  
Offshore Industry ◽  
Mapping Techniques ◽  
Vision Based Localization ◽  
And Control ◽  
State Of Art ◽  
Underwater Structures

<p><strong>Abstract.</strong> Metrology is fundamental in all the applications that require to qualify, verify and validate measured data according to standards or, in other words, to assess their compliance with predefined tolerances. At sea, metrology is commonly associated with the process of measuring underwater structures, mainly pipeline elements widely used in offshore industry. Subsea operations are very expensive; optimizing time and money resources are the core factors driving innovation in the subsea metrology industry. In this study, the authors investigate the use of state-of-art vision-based algorithms, i.e. ORB-SLAM2 and Visual Odometry, as a navigation tool to assist and control a Remotely Operated Vehicle (ROV) while performing subsea metrology operations. In particular, the manuscript will focus on methods for assessing the accuracy of both trajectory and tie points provided by the tested approaches and evaluating whether the preliminary real time reconstruction meets the tolerances defined in typical subsea metrology scenarios.</p>

Development of an Underwater Remotely Operated Vehicle (ROV) for Surveillance and Inspection of Port Facilities

2010 ◽  
Author(s):  
Luis B. Gutierrez ◽  
Carlos A. Zuluaga ◽  
Juan A. Ramirez ◽  
Rafael E. Vasquez ◽  
Diego A. Florez ◽  
...  
Keyword(s):  
Visual Information ◽  
Degrees Of Freedom ◽  
Pid Controllers ◽  
Remotely Operated Vehicle ◽  
Design Constraints ◽  
Computational Tools ◽  
Port Facilities ◽  
Oceanographic Research ◽  
And Control ◽  
Underwater Structures

This work addresses the development of an underwater remotely operated vehicle (ROV), required to obtain reliable visual information, used for surveillance and maintenance of ship shells and underwater structures of Colombian port facilities and oceanographic research. The most relevant design constraints were evaluated considering environmental conditions, dimensional restrictions, hydrostatics, hydrodynamics, degrees of freedom and the availability of instrumentation and control hardware. The mechanical/naval design was performed through an iterative process by using computational tools CAD/CAE/CFD. The hardware architecture was divided in three layers: instrumentation, communications and control. The software was developed using ANSI C with Embedded Linux operating system. The guidance and navigation system used the Kalman filter to estimate the state of the vehicle. The vehicle can operate in manual and semi-automatic modes. In the semi-automatic, the position of a joystick is converted into the velocity set-points that are integrated to get the yaw and depth commands for the PID controllers. The rigorous design and a consistent construction processes allowed the development of a robust and reliable robotic system that constitutes an innovative product in Colombia.

Quantitative Changes of the Lipid and Fatty Acid Composition of Leaves of Aleurites montana as a Consequence of Growth under 700 ppm CO2 in the Atmosphere

1996 ◽  
Vol 51 (11-12) ◽  
pp. 833-840 ◽  
Author(s):  
P He ◽  
A Radunz ◽  
K. P Bader ◽  
G. H Schmid
Keyword(s):  
Fatty Acids ◽  
Thylakoid Membrane ◽  
Saturated Fatty Acids ◽  
Phospholipid Fraction ◽  
Phospholipid Content ◽  
The Core ◽  
Glycolipid Fraction ◽  
Carbonic Acids ◽  
And Control ◽  
Β Carotene

Abstract Leaf lipids of Aleurites plants that were cultivated for 5 months in air containing 700 ppm CO2, were compared to those of control plants cultivated at 350 ppm CO2. The content of ether soluble lipids referred to dry matter is the same in CO2-and control plants. The comparison of lipids analyzed as the pigments chlorophyll and carotenoids, phospholipids and glycolipids shows that the ratio of phospholipids and glycolipids is slightly shifted in favor of phospholipids in CO2-plants. Thus, within the group of phospholipids, phosphatidylglycerol and phosphatidylinositol occur in higher concentrations in CO2-plants. Although the differences in the lipid content appear moderate in CO2-and control plants, it is the saturation degree of fatty acids that differs substantially. The fatty acids of CO2-plants contain according to the higher phospholipid content approx. 5% more saturated fatty acids. Stearic acid is three-fold increased. Whereas in the phospholipid fraction saturated fatty acids comprise one half of all fatty acids, the unsaturated fatty acids make up for 80 to 90% in the glycolipid fraction. In CO2-plants not only in the phospholipid fraction but also in the glycolipid fraction saturated fatty acids occur in a higher portion. This means that not only in the cell membrane of CO2-plants but also in the thylakoid membrane the fluidity is decreased. Also in the wax-fraction long-chained carbonic acids with 20 -26 carbon atoms occur. As the portion of these carbonic acids is twice as high in CO2-plants, it is concluded that a stronger formation of the wax layers exists in CO2-plants. By means of Western blotting and by the use of lipid and carotenoid antisera the binding of lipids onto proteins of photosystem II and photosystem I was analyzed. It is seen that besides the major amount of lipids which build up the thylakoid membrane, some lipids are also bound to membrane peptides. Whereas monogalactolipid is bound to the LHCP-complex peptides, to the OEC1 -peptide and the 43 and 47 kDa chlorophyll binding peptides, the anionic lipids sulfoquinovosyldiglyceride and phosphatidylglycerol and digalactolipid are bound to the core peptides of PS II and PS I. β-carotene and the xanthophylls were found to be bound to the core peptides and β-carotene and violaxanthin were also bound to the light-harvesting pigment complex.

Design, Construction and Control of a Remotely Operated Vehicle (ROV)

2011 ◽  
Author(s):  
Alireza Marzbanrad ◽  
Jalil Sharafi ◽  
Mohammad Eghtesad ◽  
Reza Kamali
Keyword(s):  
High Speed ◽  
Degrees Of Freedom ◽  
Remotely Operated Vehicle ◽  
Six Degrees Of Freedom ◽  
Depth Sensors ◽  
Control Schemes ◽  
On Line ◽  
Operation Unit ◽  
And Control ◽  
Design Construction

This is report of design, construction and control of “Ariana-I”, an Underwater Remotely Operated Vehicle (ROV), built in Shiraz University Robotic Lab. This ROV is equipped with roll, pitch, heading, and depth sensors which provide sufficient feedback signals to give the system six degrees-of-freedom actuation. Although its center of gravity and center of buoyancy are positioned in such a way that Ariana-I ROV is self-stabilized, but the combinations of sensors and speed controlled drivers provide more stability of the system without the operator involvement. Video vision is provided for the system with Ethernet link to the operation unit. Control commands and sensor feedbacks are transferred on RS485 bus; video signal, water leakage alarm, and battery charging wires are provided on the same multi-core cable. While simple PI controllers would improve the pitch and roll stability of the system, various control schemes can be applied for heading to track different paths. The net weight of ROV out of water is about 130kg with frame dimensions of 130×100×65cm. Ariana-I ROV is designed such that it is possible to be equipped with different tools such as mechanical arms, thanks to microprocessor based control system provided with two directional high speed communication cables for on line vision and operation unit.

Study on Novel Automatic Steel Bundling Machine Pneumatic Control System

2012 ◽  
Vol 490-495 ◽  
pp. 594-597
Author(s):  
Cheng Qun Li ◽  
Liang Gao
Keyword(s):  
Control System ◽  
Control Program ◽  
Control Flow ◽  
Pneumatic Control ◽  
The Core ◽  
New Type ◽  
Action Process ◽  
And Control

This paper introduces a new type of automatic steel bundling machine for bundling process, which includes a pneumatic action process, mainly do some researches on the pneumatic control system. The system chooses PLC as the core control component, puts forward the hardware of control system and control flow. Eventually we have been designed the control program.

scholarly journals Morphology and Degradation of Multicompartment Microparticles Based on Semi-Crystalline Polystyrene-block-Polybutadiene-block-Poly(L-lactide) Triblock Terpolymers

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4358
Author(s):  
Nicole Janoszka ◽  
Suna Azhdari ◽  
Christian Hils ◽  
Deniz Coban ◽  
Holger Schmalz ◽  
...  
Keyword(s):  
Cross Sections ◽  
Ring Opening ◽  
Particle Diameter ◽  
Average Particle ◽  
Average Particle Diameter ◽  
Selective Degradation ◽  
The Core ◽  
Transmission Electron ◽  
And Control ◽  
Triblock Terpolymers

The confinement assembly of block copolymers shows great potential regarding the formation of functional microparticles with compartmentalized structure. Although a large variety of block chemistries have already been used, less is known about microdomain degradation, which could lead to mesoporous microparticles with particularly complex morphologies for ABC triblock terpolymers. Here, we report on the formation of triblock terpolymer-based, multicompartment microparticles (MMs) and the selective degradation of domains into mesoporous microparticles. A series of polystyrene-block-polybutadiene-block-poly(L-lactide) (PS-b-PB-b-PLLA, SBL) triblock terpolymers was synthesized by a combination of anionic vinyl and ring-opening polymerization, which were transformed into microparticles through evaporation-induced confinement assembly. Despite different block compositions and the presence of a crystallizable PLLA block, we mainly identified hexagonally packed cylinders with a PLLA core and PB shell embedded in a PS matrix. Emulsions were prepared with Shirasu Porous Glass (SPG) membranes leading to a narrow size distribution of the microparticles and control of the average particle diameter, d ≈ 0.4 µm–1.8 µm. The core–shell cylinders lie parallel to the surface for particle diameters d < 0.5 µm and progressively more perpendicular for larger particles d > 0.8 µm as verified with scanning and transmission electron microscopy and particle cross-sections. Finally, the selective degradation of the PLLA cylinders under basic conditions resulted in mesoporous microparticles with a pronounced surface roughness.

Temperature/Humidity Control System Based on Micro Controller Unit in the Room of Bikram's Yoga

2012 ◽  
Vol 529 ◽  
pp. 352-355
Author(s):  
Na Li ◽  
Yong Gang Tang ◽  
Gui Ying Wang
Keyword(s):  
Control System ◽  
Humidity Sensor ◽  
Control Unit ◽  
Data Display ◽  
Control Temperature ◽  
The Core ◽  
Wireless Transceiver ◽  
Remote System ◽  
And Control ◽  
Micro Controller Unit

This thesis has designed a temperature/humidity remote system which takes Micro controller Unit AT89S51 as the core control unit. The system consists of Micro controller Unit, SHT75 temperature/humidity sensor, Rok 101 007 wireless transceiver and PC data display modules. The system can detect and control temperature/humidity in the room of Bikram's yuga remotely to create an environment suitable for fitness in high temperature.

scholarly journals Synthesis and Control of the Shell Thickness of Polyaniline and Polypyrrole Half Hollow Spheres Using the Polystyrene Cores

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Su-Ryeon Yun ◽  
Gyeong-Ok Kim ◽  
Chan Woo Lee ◽  
Nam-Ju Jo ◽  
Yongku Kang ◽  
...  
Keyword(s):  
Shell Thickness ◽  
Hollow Spheres ◽  
Core Shell ◽  
Chemical Structures ◽  
The Core ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Core Shell Structure ◽  
And Control ◽  
Ft Ir Spectroscopy

Polyaniline (Pani) and polypyrrole (Ppy) half hollow spheres with different shell thicknesses were successfully synthesized by three steps process using polystyrene (PS) as the core. The PS core was synthesized by emulsion polymerization. Aniline and pyrrole monomers were polymerized on the surface of the PS core. The shells of Pani and Ppy were fabricated by adding different amounts of aniline and pyrrole monomers. PS cores were dissolved and removed from the core shell structure by solvent extraction. The thicknesses of the Pani and Ppy half hollow spheres were observed by FE-SEM and FE-TEM. The chemical structures of the Pani and Ppy half hollow spheres were characterized by FT-IR spectroscopy and UV-Vis spectroscopy. The shell thicknesses of the Pani half hollow spheres were 30.2, 38.0, 42.2, 48.2, and 52.4 nm, while the shell thicknesses of the Ppy half hollow spheres were 16.0, 22.0, 27.0, and 34.0 nm. The shell thicknesses of Pani and Ppy half hollow spheres linearly increased as the amount of the monomer increased. Therefore, the shell thickness of the Pani and Ppy half hollow spheres can be controlled in these ranges.

scholarly journals Knowledge transfer and transformation: moving knowledge from research to policy

Perspectiva ◽  
2011 ◽  
Vol 29 (1) ◽  
pp. 49-67
Author(s):  
Jenny Ozga
Keyword(s):  
Economic Development ◽  
Knowledge Transfer ◽  
Knowledge Economy ◽  
Policy Initiative ◽  
Community Resource ◽  
Competitive System ◽  
Economic Resource ◽  
The Core ◽  
And Control ◽  
Research To Policy

This paper focuses on Knowledge Transfer (KT) as a policy initiative. Knowledge transfer/translation has developed from policy concerns about the gap between research-based knowledge trapped in disciplinary silos and the growing information and knowledge needs of various users. In addition KT maps closely against knowledge economy assumptions as effective KT is believed to provide competitive system advantage. In this context, what is distinctive in contemporary global economic development is ‘the action of knowledge on itself as the main source of productivity’. But the production of such knowledge does not take place in a vacuum. The challenge, then, for governments driving towards knowledgebased economies is not just to promote active knowing as an economic resource but to seek to manage and contain the knowledge that generates as a collective community resource, within acceptable limits. It is the difficulties that this simultaneous need for  freedom and control presents that form the core of this paper.

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