Integrated System to Evaluate Moored Ship Behavior

2017 ◽  
Author(s):  
E. Peña ◽  
A. Figuero ◽  
J. Sande ◽  
A. Guerra ◽  
J. D. Perez ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Tracking System ◽  
Integrated System ◽  
Maritime Transportation ◽  
Measurement Unit ◽  
Mooring Lines ◽  
Additional Measure ◽  
Determining Factors ◽  
Real Behavior ◽  
The University

The development of loading and unloading operations is an essential part of the logistical chain of maritime transportation. One of the determining factors in this process is the movement of moored ships, which has a notable influence over the efficiency of the operation. The implementation of systems to characterize their real behavior would provide an important tool for the management of these activities. In this context the Water and Environmental Engineering Group (GEAMA) at the University of A Coruña, Spain (UDC), through different projects executed in collaboration with the Port Authority of A Coruña (Spain), has developed an integrated system for monitoring the dynamic behavior of moored vessels. This system includes different devices which allow to characterize their six degrees of freedom and tensions in certain mooring lines. The analysis of motions is carried out using three combined technologies. Ship rotations (roll, pitch and yaw) are registered by means of an Inertial Measurement Unit (IMU) developed by the Research Group. The translations of heave and surge are analyzed with a visual tracking system using fixed cameras deployed near the location. Finally, the evaluation of sway motion and an additional measure of yaw are obtained using two laser-distance meters located over the dock. All devices integrated in the system were calibrated in laboratory at the R+D Centre CITTEC-UDC with several series of tests. Once the methodology was validated, the system has been employed in different projects carried out in Inner and Outer Ports of the city of A Coruña, with more than 30 monitored ships.

scholarly journals An Efficient Ultra-Tight GPS/RISS Integrated System for Challenging Navigation Environments

2020 ◽  
Vol 10 (10) ◽  
pp. 3613
Author(s):  
Malek Karaim ◽  
Mohamed Tamazin ◽  
Aboelmagd Noureldin
Keyword(s):  
Urban Areas ◽  
Inertial Sensor ◽  
Tracking System ◽  
Integrated System ◽  
Measurement Unit ◽  
Gps Receiver ◽  
Signal Tracking ◽  
Signal Jamming ◽  
Reduced Inertial Sensor System ◽  
Lock In

The Global Positioning System (GPS) provides an accurate navigation solution in the open sky. However, in some environments such as urban areas or in the presence of signal jamming, GPS signals cannot be easily tracked since they could be harshly attenuated or entirely blocked. This often requires the GPS receiver to go into a signal re-acquisition phase for the corresponding satellite. To avoid the intensive computations necessary for the signal re-lock in a GPS receiver, a robust signal-tracking mechanism that can hold and/or rapidly re-lock on the signals and keep track of their dynamics becomes a necessity. This paper augments a vector-based GPS signal tracking system with a Reduced Inertial Sensor System (RISS) to produce a new ultra-tight GPS/INS integrated system that enhances receivers’ tracking robustness and sensitivity in challenging navigation environments. The introduced system is simple, efficient, reliable, yet inexpensive. To challenge the proposed method with real jamming conditions, real experiment work was conducted inside the Anechoic Chamber room at the Royal Military College of Canada (RMC). The Spirent GSS6700 signal simulator was used to generate GPS signals, and an INS Simulator is used for simulating the inertial measurement unit (IMU) to generate the corresponding trajectory raw data. The NEAT jammer, by NovAtel, was used to generate real jamming signals. Results show a good performance of the proposed method under real signal jamming conditions.

scholarly journals Development of Non Expensive Technologies for Precise Maneuvering of Completely Autonomous Unmanned Aerial Vehicles

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 391
Author(s):  
Luca Bigazzi ◽  
Stefano Gherardini ◽  
Giacomo Innocenti ◽  
Michele Basso
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Degrees Of Freedom ◽  
Vision System ◽  
Video Stream ◽  
Measurement Unit ◽  
Absolute Position ◽  
Light Load ◽  
Aerial Vehicles ◽  
Angular Velocities ◽  
Custom Hardware

In this paper, solutions for precise maneuvering of an autonomous small (e.g., 350-class) Unmanned Aerial Vehicles (UAVs) are designed and implemented from smart modifications of non expensive mass market technologies. The considered class of vehicles suffers from light load, and, therefore, only a limited amount of sensors and computing devices can be installed on-board. Then, to make the prototype capable of moving autonomously along a fixed trajectory, a “cyber-pilot”, able on demand to replace the human operator, has been implemented on an embedded control board. This cyber-pilot overrides the commands thanks to a custom hardware signal mixer. The drone is able to localize itself in the environment without ground assistance by using a camera possibly mounted on a 3 Degrees Of Freedom (DOF) gimbal suspension. A computer vision system elaborates the video stream pointing out land markers with known absolute position and orientation. This information is fused with accelerations from a 6-DOF Inertial Measurement Unit (IMU) to generate a “virtual sensor” which provides refined estimates of the pose, the absolute position, the speed and the angular velocities of the drone. Due to the importance of this sensor, several fusion strategies have been investigated. The resulting data are, finally, fed to a control algorithm featuring a number of uncoupled digital PID controllers which work to bring to zero the displacement from the desired trajectory.

scholarly journals Multi-sensor three-dimensional Monte Carlo localization for long-term aerial robot navigation

2017 ◽  
Vol 14 (5) ◽  
pp. 172988141773275 ◽  
Author(s):  
Francisco J Perez-Grau ◽  
Fernando Caballero ◽  
Antidio Viguria ◽  
Anibal Ollero
Keyword(s):  
Monte Carlo ◽  
Motion Tracking ◽  
Robot Navigation ◽  
Tracking System ◽  
Three Dimensional ◽  
Measurement Unit ◽  
Indoor Environments ◽  
Localization Algorithm ◽  
Monte Carlo Localization ◽  
Motion Tracking System

This article presents an enhanced version of the Monte Carlo localization algorithm, commonly used for robot navigation in indoor environments, which is suitable for aerial robots moving in a three-dimentional environment and makes use of a combination of measurements from an Red,Green,Blue-Depth (RGB-D) sensor, distances to several radio-tags placed in the environment, and an inertial measurement unit. The approach is demonstrated with an unmanned aerial vehicle flying for 10 min indoors and validated with a very precise motion tracking system. The approach has been implemented using the robot operating system framework and works smoothly on a regular i7 computer, leaving plenty of computational capacity for other navigation tasks such as motion planning or control.

DESIGN AND DEVELOPMENT OF AN EFFICIENT COMPUTER SIMULATION MODEL FOR RESPONSE ANALYSIS OF A MOORED SEMI-SUBMERSIBLE

2021 ◽  
Vol 161 (A1) ◽  
Author(s):  
V Domala ◽  
R Sharma
Keyword(s):  
Computer Simulation ◽  
Simulation Model ◽  
Degrees Of Freedom ◽  
Experimental Results ◽  
Response Analysis ◽  
Computer Simulation Model ◽  
Governing Equations ◽  
Design And Development ◽  
Mooring Lines ◽  
Steel Wires

This paper presents the design and development of an efficient modular ‘Computer Simulation Model (CSM)’ for response analysis of a moored semi-submersible. The computer simulation model is designed in two split models (i.e. computational and experimental models) and each of these models consists of various modules. The modules are developed from basic governing equations related to motion and modules are integrated and we aim for a seamless integration. The moored semi-submersible is represented mathematically as six degrees of freedom dynamic system and the coupling effects between the structure and mooring lines are considered. The basic geometric configuration of semi- submersible is modelled and analyzed for stability computations in MS-Excel*TM and then the basic governing equations related to motion are modelled mathematically in a module and solved numerically with Ansys-AQWA**TM. The computational model is validated and verified with some available experimental results. The CSM is utilized to study the surge and sway responses with respect to the horizontal range of mooring lines and our results show good validation with the existing experimental results. Our presented results show that the fibre wires have minimum steady state response in surge and sway degrees of freedom as compared with the steel wires. However, they have large drift as compared with steel wires. Finally, we show that the computer simulation model can help in detailed analysis of responses and results can be utilized for design and development of new age semi-submersibles for optimum performances for a given set of parameters.

Analysing and evaluating environmental information disclosure in universities: the role of corporate governance, stakeholders and culture

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jesús Mauricio Flórez-Parra ◽  
Maria Victoria Lopez-Perez ◽  
Antonio M. López Hernández ◽  
Raquel Garde Sánchez
Keyword(s):  
Information Disclosure ◽  
Stakeholder Participation ◽  
Environmental Information ◽  
Content Type ◽  
Environmental Actions ◽  
Determining Factors ◽  
Environmental Information Disclosure ◽  
Internal And External Factors ◽  
The University

Purpose The purpose of this paper is to analyse the internal and external factors related to the disclosure of environmental information in universities which reflect the actions carried out in these universities. Design/methodology/approach Taking as reference the first 200 universities in the Shanghai ranking, several factors associated with the degree of environmental information disclosure in universities – governance dimension, the relationship and participation of stakeholders, position and prestige as signs of the quality of the institution and cultural concern in the university’s country for the environment – are analysed. Findings The results obtained show that the size of the leadership team, stakeholder participation, the position of the university in rankings and cultural concern in the university’s country for the environment are determining factors in the university’s environmental actions and, consequently, in their disclosure. Other factors – such as the size of the university, the level of self-financing and financial autonomy – do not affect the disclosure of environmental information. Originality/value Scant research exists on the environmental commitments of universities; this paper aims to fill that gap. Their role as the main channel of research and as instructors of future professionals makes them points of reference in society. Research on university ranking has traditionally focussed on teaching and research results, but environmental issues are becoming increasingly important. This paper enumerates the factors that influence the dissemination of environmental information in the most prestigious universities. This research also provides an original approach by considering not only top-down but also bottom-up strategies through communication channels and the incidence of cultural factors.

Numerical Simulation of Multiple Floating Structures With Nonlinear Constraints

2002 ◽  
Vol 124 (2) ◽  
pp. 104-109 ◽  
Author(s):  
Subrata K. Chakrabarti
Keyword(s):  
Degrees Of Freedom ◽  
Order Theory ◽  
Frequency Domain Analysis ◽  
Body Motion ◽  
Single Frequency ◽  
Integration Scheme ◽  
Mooring Lines ◽  
Floating Structures ◽  
Irregular Wave ◽  
Exciting Forces

A versatile and efficient numerical analysis is developed to compute the responses of a moored floating system composed of multiple floating structures. Structures such as tankers, semisubmersibles, FPSOs, SPARs, TLPs, and SPMs connected by mooring lines, connectors or fenders may be analyzed individually or collectively including multiple interaction. The analysis is carried out in the time domain assuming rigid body motion for the structures, and the solution is generated by a forward integration scheme. The analysis includes the nonlinearities in the excitation, damping, and restoring terms encountered in a typical mooring system configuration. It also allows for instabilities in the tower oscillation as well as slack mooring lines. Certain simplifications in the analysis have been made, which are discussed. The exciting forces in the analysis are wind, current, and waves (including a steady and an oscillating drift force), which are not necessarily collinear. The waves can be single frequency or composed of multiple frequency components. For regular waves either linear, stretched linear or fifth order theory may be used. The irregular wave may be included as a given spectral model (e.g., PM or JONSWAP). The vessels are free to respond to the exciting forces in six degrees of freedom—surge, sway, heave, roll, pitch, and yaw. The tower, when present, is free to respond in two degrees of freedom—oscillation and precession. The loads in the mooring lines are determined from prescribed tension-strain tables for the lines. Rigid mooring arms can be analyzed by allowing for compression in the load-strain table. Fenders may be input similarly through load compression tables. In order to establish the stability and accuracy of the solution, comparison of the results with linearized frequency domain analysis was made. The analysis is verified by several different model test results for different structure configurations in regular and random seas. Some of the interesting aspects of nonlinear system are shown with a few examples.

scholarly journals Incremento de la participación mediante la gamificación en la asignatura Dirección de Operaciones del Grado en Administración y Dirección de Empresas

2021 ◽  
Vol 2 (3) ◽  
pp. 4791-4806
Author(s):  
Miguel Ángel Montañés Del Río ◽  
Vanessa María Rodríguez Cornejo ◽  
Margarita Ruiz Rodríguez ◽  
Jaime Sánchez Ortiz
Keyword(s):  
Mobile Devices ◽  
Operations Management ◽  
Knowledge Society ◽  
Learning Processes ◽  
Learning Models ◽  
Determining Factors ◽  
New Learning ◽  
Training Methodologies ◽  
Teaching Learning ◽  
The University

RESUMEN En la actual sociedad de la información y del conocimiento se observa cómo la proliferación y el auge de los dispositivos móviles, hacen surgir nuevos modelos de aprendizaje que reformulan las metodologías didácticas, organizativas, y de formación de los currículos, para innovar en educación (Moreno Martínez, Leiva Olivencia, & Matas Terrón, 2016). Los estudios que identifican las tecnologías emergentes que podrían impactar en el aprendizaje, la enseñanza y la investigación, prevén el aumento del uso y la incorporación de dispositivos y aplicaciones móviles en las aulas (Reig, 2013; Reig & Vílchez, 2013). Destaca el aprendizaje basado en juegos o gamificación, que permite desarrollar procesos de enseñanza-aprendizaje que facilitan la cohesión, la integración y la motivación, potenciando la creatividad del alumnado. Crear juegos entretenidos motivará al alumnado para que participe de forma activa en clase, fomentará una sana competencia entre los jugadores, y hará del aprendizaje algo más divertido (Aleksić-Maslać, Rašić, & Vranešić, 2018). Utilizando Kahoot en dispositivos móviles como soporte para las clases de Dirección de Operaciones del Grado en Administración y Dirección de Empresas de la Universidad de Cádiz, se consiguió motivar al alumnado y, aun existiendo otros factores determinantes, mejorar sus resultados de evaluación.   ABSTRACT In today's information and knowledge society, the proliferation and rise of mobile devices has led to the emergence of new learning models that reformulate didactic, organizational and curricular training methodologies in order to innovate in education (Moreno Martínez, Leiva Olivencia, & Matas Terrón, 2016). Studies that identify emerging technologies that could impact learning, teaching and research, foresee increased use and incorporation of mobile devices and applications in classrooms (Reig, 2013; Reig & Vílchez, 2013). Learning based on games or gamification stands out, which allows the development of teaching-learning processes that facilitate cohesion, integration and motivation, boosting students' creativity. Creating entertaining games will motivate students to participate actively in class, encourage healthy competition between players, and make learning more fun (Aleksić-Maslać, Rašić, & Vranešić, 2018). Using Kahootin mobile devices as support for the classes of Operations Management of the Degree in Business Administration and Management of the University of Cadiz, it was possible to motivate the students and, although there are other determining factors, to improve their evaluation results.    

scholarly journals Hábitos lectores de los adolescentes en un ecosistema llamado escuela: factores determinantes en estudiantes de educación secundaria

2020 ◽  
pp. 1-34
Author(s):  
Manuel Francisco Romero Oliva ◽  
Alba Ambrós Pallarés ◽  
Fernando Trujillo Sáez
Keyword(s):  
Secondary Education ◽  
Design Research ◽  
Ministry Of Education ◽  
Education Students ◽  
Reading Habits ◽  
Complex Issue ◽  
Determining Factors ◽  
Research Plan ◽  
Education Culture ◽  
The University

This work is part of the project “Determining factors in the reading habits of Secondary Education students. A study from the variables of the educational context” (PR2017040), financed by the Own Research Plan of the University of Cadiz. The main objective of the study is focused on analyzing those determining factors that affect the formation of new readers in the school in a global and integrating way. Taking as a reference the idea of the ecosystem or ecological environment of Bronfenbrenner (2001), an analogy is made with the educational system and the agents that intervene in the reading habits of adolescents in their educational stage of Compulsory Secondary Education (ESO). These approaches were used to review a Questionnaire on Reading Habits, which the Ministry of Education, Culture and Sport presented in an ambitious Plan to Promote Reading in 2001 and to adapt it to the needs of the PR2017040 Project. The conclusions illustrate that this complex issue of reading habits cannot be studied with a questionnaire as the only research instrument, since it is necessary to give voice to the different agents that participate in the process and, therefore, agree with Molina et al. (2011) in proposing the design research model to understand and improve the educational reality through the consideration of natural contexts in all their complexity.

scholarly journals A Low-Cost Motion Capture System for Small-Scale Wave Energy Device Tank Testing

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Francesco Paparella ◽  
Satja Sivcev ◽  
Daniel Toal ◽  
John V. Ringwood
Keyword(s):  
Wave Energy ◽  
Motion Tracking ◽  
Tracking System ◽  
Low Cost ◽  
Measurement Unit ◽  
Small Scale ◽  
Energy Device ◽  
Optical Motion ◽  
Optical Motion Tracking ◽  
Motion Tracking System

The measurement of the motion of a small-scale wave energy device during wave tank tests is important for the evaluation of its response to waves and the assessment of power production. Usually, the motion of a small-scale wave energy converter (WEC) is measured using an optical motion tracking system with high precision and sampling rate. However, the cost for an optical motion tracking system can be considerably high and, therefore, the overall cost for tank testing is increased. This paper proposes a low-cost capture system composed of an inertial measurement unit and ultrasound sensors. The measurements from the ultrasound sensors are combined optimally with the measurements from the inertial measurement unit through an extended Kalman filter (EKF) in order to obtain an accurate estimation of the motion of a WEC.

Model Tests for Safe-Return-to-Port of a Damaged Ship in Waves

2015 ◽  
Author(s):  
Jeonghwa Seo ◽  
Cristobal Santiago Bravo ◽  
Shin Hyung Rhee
Keyword(s):  
Degrees Of Freedom ◽  
Feedback System ◽  
Model Tests ◽  
Measurement Unit ◽  
Test Model ◽  
Motion Response ◽  
Six Degrees Of Freedom ◽  
Heading Angle ◽  
Wave Conditions ◽  
Damaged Ship

A series of tests using a course-keeping model ship with an autopilot system were carried out in a towing tank for research on Safe-Return-to-Port (SRTP). The autopilot system controls the rudder angle and propeller revolution rate by a feedback system. The variation of the heading angle of the test model with different control parameters was investigated first, to ensure that the test model had sufficient course-keeping maneuverability in severe wave conditions. The wave conditions and propeller revolution rate were selected based on SRTP regulations. Tests were conducted in wave conditions corresponding to sea states 4 to 6. The six-degrees-of-freedom motion response of the test model was measured by a wireless inertial measurement unit and gyro sensors to achieve fully wireless model tests. The advance speed and motion response in various wave conditions were measured and analyzed to investigate the effects of flooding behavior in a damaged condition and of waves on the propulsion and maneuvering performance of the damaged ship model.

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