Status of the Atlas Elektronik’s Modular AUV Family

2006 ◽  
Author(s):  
Willi Hornfeld
Keyword(s):  
Autonomous Underwater Vehicles ◽  
Leading Edge ◽  
Cost Effective ◽  
Control Site ◽  
Single Type ◽  
Quality Of Data ◽  
Diving Depth ◽  
Sea Bed ◽  
Wide Range ◽  
Logistic Support

As opposed to ROVs (Remotely Operated Vehicles), self-propelled, unmanned autonomous underwater vehicles (AUVs) are becoming increasingly important since, unlike ROVs they can operate completely self-sufficiently, i.e. independent of the carrier platform and cable at practically any depth and for long periods of time, require only minor technical and logistic support and can be used in regions which are inaccessible to manned submersibles or ROVs (e.g. under ice regions). In other words, AUVs are distinguished by a wide range of applications, the extremely high quality of data collected, their very cost-effective operation and the large standoff capability to the carrier platform, the latter bringing about a distinct improvement in terms of carrier platform safety e.g. for military missions. Due to these advantages over conventional systems, AUVs can be employed for a whole variety of applications, such as the following in the commercial sector: • Sea Bed Mapping, • Pipeline and Route Survey, • Inspection/Control, • Site Clearance, • Debris Survey, • Science – Search – Environment – Geology, • Harbour and ship’s hull inspection. Moreover AUVs will play an important role in the military scenario like mine countermeasure as well. Obviously, one single type of AUV will be unable to cover this entire spectrum if — above and beyond the aforementioned applications — one considers the different operating depths ranging from coastal regions (about 10 m) to deep water (approx. 4000 m) and the various possible carrier platforms (helicopters, ships, submarines, shore stations). On the other hand, the development and use of one specific type of AUV for one or a very limited number of mission types would be very expensive, both in terms of costs involved and necessary logistics, and would hardly be acceptable on the market. The solution to this problem is the “modularity” of the AUV subsystems as well as a family concept for the vehicle design. To implement this strategy, ATLAS ELEKTRONIK has forced the development and marketing of an AUV family for a wide array of missions. The family starts with the SeaFox-IQ, a very small and lightweight (40 kg) AUV for 300 m diving depth, based on the extreme successful mine disposal ROV SeaFox. The big brother is the SeaStout, a 100 kg AUV, designed for 300 m too. The SeaOtter Mk1 and SeaOtter Mk2 AUVs are 1500 kg and 1100 kg vehicles for 600 m operations. The leading edge is the AUV DeepC, a 2500 kg experimental vehicle developed for 4000 m depth and up to 60 h endurance. The ATLAS AUV family offer a lot of hard- and software commonality to ensure that serviceability is maintained, while having a high degree of “customisation” in key areas like payload sensor selection ensuring they will meet customer needs.

scholarly journals Development of Modular Bio-Inspired Autonomous Underwater Vehicle for Close Subsea Asset Inspection

2021 ◽  
Vol 11 (12) ◽  
pp. 5401
Author(s):  
Wael Gorma ◽  
Mark A. Post ◽  
James White ◽  
James Gardner ◽  
Yang Luo ◽  
...  
Keyword(s):  
Autonomous Underwater Vehicle ◽  
Autonomous Underwater Vehicles ◽  
Magnetic Coupling ◽  
Wind Farms ◽  
Cost Effective ◽  
Offshore Wind ◽  
Offshore Wind Farms ◽  
Physical Constraints ◽  
Modular Software ◽  
Wide Range

To reduce human risk and maintenance costs, Autonomous Underwater Vehicles (AUVs) are involved in subsea inspections and measurements for a wide range of marine industries such as offshore wind farms and other underwater infrastructure. Most of these inspections may require levels of manoeuvrability similar to what can be achieved by tethered vehicles, called Remotely Operated Vehicles (ROVs). To extend AUV intervention time and perform closer inspection in constrained spaces, AUVs need to be more efficient and flexible by being able to undulate around physical constraints. A biomimetic fish-like AUV known as RoboFish has been designed to mimic propulsion techniques observed in nature to provide high thrust efficiency and agility to navigate its way autonomously around complex underwater structures. Building upon advances in acoustic communications, computer vision, electronics and autonomy technologies, RoboFish aims to provide a solution to such critical inspections. This paper introduces the first RoboFish prototype that comprises cost-effective 3D printed modules joined together with innovative magnetic coupling joints and a modular software framework. Initial testing shows that the preliminary working prototype is functional in terms of water-tightness, propulsion, body control and communication using acoustics, with visual localisation and mapping capability.

DeepStar 11304: Laying the Groundwork for AUV Standards for Deepwater Fields

2013 ◽  
Vol 47 (3) ◽  
pp. 13-18 ◽  
Author(s):  
John Jacobson ◽  
Pierce Cohen ◽  
Amin Nasr ◽  
Art J. Schroeder ◽  
Greg Kusinski
Keyword(s):  
Oil And Gas ◽  
Autonomous Underwater Vehicles ◽  
Cost Effective ◽  
Oil And Gas Industry ◽  
Economic Benefits ◽  
Regulatory Oversight ◽  
Early Adoption ◽  
Regulatory Standards ◽  
Industry Standards ◽  
Wide Range

AbstractEmerging autonomous underwater vehicles (AUVs) developments across the oil and gas industry now include pipeline inspection; structural survey; deepwater inspection, repair and maintenance (IRM); and field resident systems for remote/harsh environments. As these capabilities mature, AUVs will become an increasingly important tool for deepwater field operations. Early adoption of AUV standards will facilitate more rapid deployment of AUV technologies and enable the industry to reap a wide range of safety, environmental, operational, and economic benefits for its deepwater fields. The development of industry standards for AUV interfaces will facilitate more rapid implementation of AUV capabilities and lead to more cost-effective, compatible system designs by AUV vendors and field hardware manufacturers. The development of regulatory standards for the interpretation and acceptance of autonomous inspection results is also an essential step toward the achievement of more cost-effective operations and regulatory oversight of deepwater subsea fields. This paper describes a future vision for the use of AUVs in deepwater field operations, the benefits to be realized, and the future capabilities of AUVs that must be anticipated and facilitated within AUV standards to achieve that vision. Additionally, this paper describes the goals and objectives of DeepStar Project 11304, which is laying the groundwork to achieve accelerated standardization of AUV interfaces and the development of regulatory standards for AUV inspections.

2D Color-Intensity Representation of Ultrasonic Thickness Gauge Measurements

2020 ◽  
pp. 1192-1198
Author(s):  
M.S. Mohammad ◽  
Tibebe Tesfaye ◽  
Kim Ki-Seong
Keyword(s):  
Cost Effective ◽  
The Other ◽  
Thickness Gauge ◽  
Color Intensity ◽  
Digital Readout ◽  
Flat Surfaces ◽  
Video Cameras ◽  
Wide Range ◽  
Cost Effective Alternative ◽  
Ultrasonic Thickness

Ultrasonic thickness gauges are easy to operate and reliable, and can be used to measure a wide range of thicknesses and inspect all engineering materials. Supplementing the simple ultrasonic thickness gauges that present results in either a digital readout or as an A-scan with systems that enable correlating the measured values to their positions on the inspected surface to produce a two-dimensional (2D) thickness representation can extend their benefits and provide a cost-effective alternative to expensive advanced C-scan machines. In previous work, the authors introduced a system for the positioning and mapping of the values measured by the ultrasonic thickness gauges and flaw detectors (Tesfaye et al. 2019). The system is an alternative to the systems that use mechanical scanners, encoders, and sophisticated UT machines. It used a camera to record the probe’s movement and a projected laser grid obtained by a laser pattern generator to locate the probe on the inspected surface. In this paper, a novel system is proposed to be applied to flat surfaces, in addition to overcoming the other limitations posed due to the use of the laser projection. The proposed system uses two video cameras, one to monitor the probe’s movement on the inspected surface and the other to capture the corresponding digital readout of the thickness gauge. The acquired images of the probe’s position and thickness gauge readout are processed to plot the measured data in a 2D color-coded map. The system is meant to be simpler and more effective than the previous development.

The Future of Plasma-Based Surface Engineering Techniques in Tribology (Keynote)

2005 ◽  
Author(s):  
Allan Matthews ◽  
Adrian Leyland
Keyword(s):  
Surface Engineering ◽  
Performance Enhancement ◽  
Bulk Material ◽  
Cost Savings ◽  
Cost Effective ◽  
Ceramic Coatings ◽  
Performance Improvements ◽  
Treatment Techniques ◽  
Wide Range ◽  
Macro Scale

Over the past twenty years or so, there have been major steps forward both in the understanding of tribological mechanisms and in the development of new coating and treatment techniques to better “engineer” surfaces to achieve reductions in wear and friction. Particularly in the coatings tribology field, improved techniques and theories which enable us to study and understand the mechanisms occurring at the “nano”, “micro” and “macro” scale have allowed considerable progress to be made in (for example) understanding contact mechanisms and the influence of “third bodies” [1–5]. Over the same period, we have seen the emergence of the discipline which we now call “Surface Engineering”, by which, ideally, a bulk material (the ‘substrate’) and a coating are combined in a way that provides a cost-effective performance enhancement of which neither would be capable without the presence of the other. It is probably fair to say that the emergence and recognition of Surface Engineering as a field in its own right has been driven largely by the availability of “plasma”-based coating and treatment processes, which can provide surface properties which were previously unachievable. In particular, plasma-assisted (PA) physical vapour deposition (PVD) techniques, allowing wear-resistant ceramic thin films such as titanium nitride (TiN) to be deposited on a wide range of industrial tooling, gave a step-change in industrial productivity and manufactured product quality, and caught the attention of engineers due to the remarkable cost savings and performance improvements obtained. Subsequently, so-called 2nd- and 3rd-generation ceramic coatings (with multilayered or nanocomposite structures) have recently been developed [6–9], to further extend tool performance — the objective typically being to increase coating hardness further, or extend hardness capabilities to higher temperatures.

scholarly journals Gamma models for estimating the odds ratio for a skewed biomarker measured in pools and subject to errors

Biostatistics ◽  
2019 ◽  
Author(s):  
Dane R Van Domelen ◽  
Emily M Mitchell ◽  
Neil J Perkins ◽  
Enrique F Schisterman ◽  
Amita K Manatunga ◽  
...  
Keyword(s):  
Odds Ratio ◽  
Adjusted Odds Ratio ◽  
Lower Cost ◽  
Cost Effective ◽  
Ratio Estimation ◽  
Statistical Efficiency ◽  
Function Model ◽  
Processing Error ◽  
Wide Range ◽  
Pooled Samples

SUMMARYMeasuring a biomarker in pooled samples from multiple cases or controls can lead to cost-effective estimation of a covariate-adjusted odds ratio, particularly for expensive assays. But pooled measurements may be affected by assay-related measurement error (ME) and/or pooling-related processing error (PE), which can induce bias if ignored. Building on recently developed methods for a normal biomarker subject to additive errors, we present two related estimators for a right-skewed biomarker subject to multiplicative errors: one based on logistic regression and the other based on a Gamma discriminant function model. Applied to a reproductive health dataset with a right-skewed cytokine measured in pools of size 1 and 2, both methods suggest no association with spontaneous abortion. The fitted models indicate little ME but fairly severe PE, the latter of which is much too large to ignore. Simulations mimicking these data with a non-unity odds ratio confirm validity of the estimators and illustrate how PE can detract from pooling-related gains in statistical efficiency. These methods address a key issue associated with the homogeneous pools study design and should facilitate valid odds ratio estimation at a lower cost in a wide range of scenarios.

scholarly journals Sporulation in solventogenic and acetogenic clostridia

2021 ◽  
Author(s):  
Mamou Diallo ◽  
Servé W. M. Kengen ◽  
Ana M. López-Contreras
Keyword(s):  
Current Knowledge ◽  
Carbon Sources ◽  
Cost Effective ◽  
Biotechnological Production ◽  
Key Points ◽  
Wide Range ◽  
Potential Applications ◽  
A Cell ◽  
Sporulation Initiation ◽  
Solventogenic Clostridia

AbstractThe Clostridium genus harbors compelling organisms for biotechnological production processes; while acetogenic clostridia can fix C1-compounds to produce acetate and ethanol, solventogenic clostridia can utilize a wide range of carbon sources to produce commercially valuable carboxylic acids, alcohols, and ketones by fermentation. Despite their potential, the conversion by these bacteria of carbohydrates or C1 compounds to alcohols is not cost-effective enough to result in economically viable processes. Engineering solventogenic clostridia by impairing sporulation is one of the investigated approaches to improve solvent productivity. Sporulation is a cell differentiation process triggered in bacteria in response to exposure to environmental stressors. The generated spores are metabolically inactive but resistant to harsh conditions (UV, chemicals, heat, oxygen). In Firmicutes, sporulation has been mainly studied in bacilli and pathogenic clostridia, and our knowledge of sporulation in solvent-producing or acetogenic clostridia is limited. Still, sporulation is an integral part of the cellular physiology of clostridia; thus, understanding the regulation of sporulation and its connection to solvent production may give clues to improve the performance of solventogenic clostridia. This review aims to provide an overview of the triggers, characteristics, and regulatory mechanism of sporulation in solventogenic clostridia. Those are further compared to the current knowledge on sporulation in the industrially relevant acetogenic clostridia. Finally, the potential applications of spores for process improvement are discussed.Key Points• The regulatory network governing sporulation initiation varies in solventogenic clostridia.• Media composition and cell density are the main triggers of sporulation.• Spores can be used to improve the fermentation process.

An intelligent algorithm for autonomous scientific sampling with the VALKYRIE cryobot

2017 ◽  
Vol 17 (3) ◽  
pp. 247-257 ◽  
Author(s):  
Evan B. Clark ◽  
Nathan E. Bramall ◽  
Brent Christner ◽  
Chris Flesher ◽  
John Harman ◽  
...  
Keyword(s):  
Human Performance ◽  
Autonomous Underwater Vehicles ◽  
Field Performance ◽  
Planetary Science ◽  
Operating Environment ◽  
Intelligent Algorithm ◽  
Future State ◽  
Science Operations ◽  
Wide Range ◽  
Matanuska Glacier

AbstractThe development of algorithms for agile science and autonomous exploration has been pursued in contexts ranging from spacecraft to planetary rovers to unmanned aerial vehicles to autonomous underwater vehicles. In situations where time, mission resources and communications are limited and the future state of the operating environment is unknown, the capability of a vehicle to dynamically respond to changing circumstances without human guidance can substantially improve science return. Such capabilities are difficult to achieve in practice, however, because they require intelligent reasoning to utilize limited resources in an inherently uncertain environment. Here we discuss the development, characterization and field performance of two algorithms for autonomously collecting water samples on VALKYRIE (Very deep Autonomous Laser-powered Kilowatt-class Yo-yoing Robotic Ice Explorer), a glacier-penetrating cryobot deployed to the Matanuska Glacier, Alaska (Mission Control location: 61°42′09.3″N 147°37′23.2″W). We show performance on par with human performance across a wide range of mission morphologies using simulated mission data, and demonstrate the effectiveness of the algorithms at autonomously collecting samples with high relative cell concentration during field operation. The development of such algorithms will help enable autonomous science operations in environments where constant real-time human supervision is impractical, such as penetration of ice sheets on Earth and high-priority planetary science targets like Europa.

scholarly journals Achieving Viral Suppression in 90% of People Living With Human Immunodeficiency Virus on Antiretroviral Therapy in Low- and Middle-Income Countries: Progress, Challenges, and Opportunities

2018 ◽  
Vol 66 (10) ◽  
pp. 1487-1491 ◽  
Author(s):  
Jean B Nachega ◽  
Nadia A Sam-Agudu ◽  
Lynne M Mofenson ◽  
Mauro Schechter ◽  
John W Mellors
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Suppression ◽  
Cost Effective ◽  
Term Treatment ◽  
Middle Income ◽  
Middle Income Countries ◽  
Long Term Treatment ◽  
Wide Range ◽  
Immunodeficiency Virus ◽  
Low And Middle Income

Abstract Although significant progress has been made, the latest data from low- and middle-income countries show substantial gaps in reaching the third “90%” (viral suppression) of the UNAIDS 90-90-90 goals, especially among vulnerable and key populations. This article discusses critical gaps and promising, evidence-based solutions. There is no simple and/or single approach to achieve the last 90%. This will require multifaceted, scalable strategies that engage people living with human immunodeficiency virus, motivate long-term treatment adherence, and are community-entrenched and ‑supported, cost-effective, and tailored to a wide range of global communities.

Experimental Studies of Leading Edge Contouring Influence on Secondary Losses in Transonic Turbines

2012 ◽  
Author(s):  
Ranjan Saha ◽  
Jens Fridh ◽  
Torsten Fransson ◽  
Boris I. Mamaev ◽  
Mats Annerfeldt
Keyword(s):  
Gas Turbine ◽  
Guide Vane ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Leading Edge ◽  
Secondary Flows ◽  
Noticeable Effect ◽  
Flow Angle ◽  
Wide Range ◽  
Contour Plots

An experimental study of the hub leading edge contouring using fillets is performed in an annular sector cascade to observe the influence of secondary flows and aerodynamic losses. The investigated vane is a three dimensional gas turbine guide vane (geometrically similar) with a mid-span aspect ratio of 0.46. The measurements are carried out on the leading edge fillet and baseline cases using pneumatic probes. Significant precautions have been taken to increase the accuracy of the measurements. The investigations are performed for a wide range of operating exit Mach numbers from 0.5 to 0.9 at a design inlet flow angle of 90°. Data presented include the loading, fields of total pressures, exit flow angles, radial flow angles, as well as profile and secondary losses. The vane has a small profile loss of approximately 2.5% and secondary loss of about 1.1%. Contour plots of vorticity distributions and velocity vectors indicate there is a small influence of the vortex-structure in endwall regions when the leading edge fillet is used. Compared to the baseline case the loss for the filleted case is lower up to 13% of span and higher from 13% to 20% of the span for a reference condition with Mach no. of 0.9. For the filleted case, there is a small increase of turning up to 15% of the span and then a small decrease up to 35% of the span. Hence, there are no significant influences on the losses and turning for the filleted case. Results lead to the conclusion that one cannot expect a noticeable effect of leading edge contouring on the aerodynamic efficiency for the investigated 1st stage vane of a modern gas turbine.

A method for correcting acoustic finite-difference amplitudes for elastic effects

Geophysics ◽  
2014 ◽  
Vol 79 (4) ◽  
pp. T243-T255 ◽  
Author(s):  
James W. D. Hobro ◽  
Chris H. Chapman ◽  
Johan O. A. Robertsson
Keyword(s):  
Wave Equation ◽  
Finite Difference ◽  
Effective Means ◽  
Cost Effective ◽  
P Wave ◽  
S Waves ◽  
Velocity Models ◽  
Acoustic Simulation ◽  
Wide Range ◽  
Elastic Simulation

We present a new method for correcting the amplitudes of arrivals in an acoustic finite-difference simulation for elastic effects. In this method, we selectively compute an estimate of the error incurred when the acoustic wave equation is used to approximate the behavior of the elastic wave equation. This error estimate is used to generate an effective source field in a second acoustic simulation. The result of this second simulation is then applied as a correction to the original acoustic simulation. The overall cost is approximately twice that of an acoustic simulation but substantially less than the cost of an elastic simulation. Because both simulations are acoustic, no S-waves are generated, so dispersed converted waves are avoided. We tested the characteristics of the method on a simple synthetic model designed to simulate propagation through a strong acoustic impedance contrast representative of sedimentary geology. It corrected amplitudes to high accuracy for reflected arrivals over a wide range of incidence angles. We also evaluated results from simulations on more complex models that demonstrated that the method was applicable in realistic sedimentary models containing a wide range of seismic contrasts. However, its accuracy was reduced for wide-angle reflections from very high impedance contrasts such as a shallow top-salt interface. We examined the influence of modeling at coarse grid resolutions, in which converted S-waves in the equivalent elastic simulation are dispersed. These results provide some validation for the accuracy of the method when applied using finite-difference grids designed for acoustic modeling. The method appears to offer a cost-effective means of modeling elastic amplitudes for P-wave arrivals in a useful range of velocity models. It has several potential applications in imaging and inversion.

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