Person:
Esteban San Román, Segundo

First Name

Segundo

Last Name

Esteban San Román

URI

https://hdl.handle.net/20.500.14352/78662

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Informática

Department

Arquitectura de Computadores y Automática

Area

Arquitectura y Tecnología de Computadores

Identifiers

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Search Results

Now showing 1 - 10 of 11

A fast autonomous scaled ship for experimental seakeeping control studies
(Oceans 2005 - Europe, 2005) Esteban San Román, Segundo; Recas Piorno, Joaquín; Girón Sierra, José María; Cruz García, Jesús Manuel de la; Riola, J. M.
A second part of our research on the seakeeping control in fast ferries, is devoted to general heading and sea state conditions. Although scaled ships are basis for experimental studies, it is not possible to keep using them in towing tanks. The main reason is that high speeds require large space for experiments, so towing tanks are not large enough. This has been noticed after the first part of our research, with head seas, in a 150m x 30m towing tank with wavemaker. Consequently, we are preparing for open air experiments. A new fast autonomous scaled ship has been developed. She is self-propelled, and is self-governed by an embedded PC on-board. The ship carries sensors for heading, speed and seakeeping control. Several scaled moving appendages have been added: two transom flaps, two lateral fins, and a T-foil. The ship uses two scaled waterjets, which also control the heading: the ship has no rudder. A distributed monitoring and control system has been designed and implemented for on-board operation. All equipment has to be very light, since the real fast ferry that we reproduce at 1/40 scale is aluminium made. A digital radio link has been provided for distant off-shore monitoring. The paper describes the autonomous ship, the on-board monitoring and control system, and shows several experimental results with quiet waters and with several types of waves.
Experimental framework for autonomous fast ships's control design
(Proceedings of the 7th WSEAS International Conference on Automatic Control, Modeling and Simulation, 2005) Recas Piorno, Joaquín; Esteban San Román, Segundo; Girón Sierra, José María; Cruz García, Jesús Manuel de la
The research on seakeeping control of fast ships requires difficult experiments for modeling and control design. To alleviate the ship motion certain active appendages are added, such moving flaps, T-foil and fins. The motion of appendages must be optimized to counteract each encountered wave. During our first research steps, a scaled down ship, with scaled appendages, has been used in a towing tank facility. The scaled ship is towed at fixed speeds of experimental interest, for instance at the equivalent to 40 knots. The wavemaker in the towing tank is used to generate specified waves. Along the experiments it was noticed that the towing of the replica spoils certain expected phenomena. A more appropriate way of doing experiments to observe all ship motions, is to use an autonomous self-propelled scaled ship. In this paper a new autonomous scaled ship is presented. It contains an on-board control system, so the ship is self-governed. Complex maneuvering can be programmed for certain study interests. Our autonomous ship is linked via radio with an external monitoring system. The ship and the off-shore monitoring system constitute an experimental framework for advanced studies about fast ship control.
Distributed electronic system for monitoring and control of a fast ship physical model
(IECON'03: The 29th Annual Conference of the IEEE Industrial Electronics Society, vols 1 - 3, Proceedings, 2003) Girón Sierra, José María; Esteban San Román, Segundo; Recas Piorno, Joaquín; Andrés Toro, Bonifacio de; Besada Portas, Eva; Cruz García, Jesús Manuel de la
This paper is related with a research on vertical motion alleviation of fast ferries. A scaled down replica of a fast ferry was built, for experimental studies in a towing tank facility. Some submerged moving actuators were added to the replica: a pair of transom flaps, lateral fins and a T-foil near the bow. Two series of experiments with waves generated in a large basin must be done. One of the series is devoted to modelling, and the second for model-based control studies. Due to the fast motions of the experimental ship, it is not possible to attach it to a computerized carriage with instrumentation (it is part of the towing tank facility). Instead, the experimental ship must be autonomous, with all monitoring and control systems on board. Since there are six motions of the ship to be considered, the number of on-board sensors and actuators, and the complexity of control, take us to decide the design of a distributed electronic system. It is based on a central embedded PC, several microcomputer nodes, and the CANbus. The on board system interacts, using a wireless data link, with an off-shore experiment control and data processing system, with an interesting visualization performance. The purpose of the paper is to introduce this system and the associated experimental framework.
EDROOM. Automatic C++ code generator for real time systems modelled with room
(New Technologies for Computer Control 2001, 2002) Polo, O. R.; Cruz García, Jesús Manuel de la; Girón Sierra, José María; Esteban San Román, Segundo
The development of real-time control systems is usually part of a design cycle, involving implementation, experimental control system testing, and re-design. For a faster and better complete development, a software engineering approach, based on a modelling language, is recommended. A successful alternative is ROOM: a modelling language with a graphical syntax. In this paper EdROOM is presented: an environment developed to graphically edit ROOM models and to automatically generate, from the models, C++ real-time control code for direct experimental application. The code generated is modular and easy to debug. The paper describes the design of the environment, with the key aspects of the modelling methodology. EdROOM has been used by our research team for several applications, with satisfactory results. One of these applications concerns the control of actuators of a fast ship for vertical motion smoothing: this is described as an example of EdROOM use.
Development of a control-oriented model of the vertical motions of a fast ferry
(Journal of Ship Research, 2004) Esteban San Román, Segundo; Girón Sierra, José María; Andrés Toro, Bonifacio de; Cruz García, Jesús Manuel de la
As a main part of a research study on the control of active flaps and a T-foil of a high-speed ferry, a control-oriented model of vertical motions of the ship has been developed. The objective of the control is to improve comfort, decreasing the impact of heave and pitch motions. We have experimental data from a towing tank institution and simulations with PRECAL. The model is based on a decomposition of the physic phenomena into two main aspects: the coupling of the ship with distance between waves and the dynamics of a semisubmerged mass. The model can be handled with MATLAB-SIMULINK, which is useful for studying control strategies. The model shows good agreement (model validation) with the experimental and simulated data for regular and irregular waves. The article shows a methodology, based on MATLAB tools, for obtaining control-oriented models from computer-aided design (CAD)-based programs. That means that the control-oriented model can be derived from the ship design, even before the ship is built.
Control code generator used for control experiments in ship scale model.
(Trol Applications in Marine Systems 2001 (CAMS 2001), 2002) Polo, O. R.; Esteban San Román, Segundo; Marón, A.; Grau, L.; Cruz García, Jesús Manuel de la
After a study of control design to get a good candidate for testing, it comes a step of experimental confirmation. The general objective of the research is to smooth the vertical motions of a fast ferry. A T-foil and transom flaps are added to a scaled-down replica of the fast ferry. These appendages can move under control. So there is a control system installed on the replica, that moves the appendages using motors, and measures the main variables of the ship and actuators motions. This control system is based on an industrial PC with electronic interfaces for motors and sensors. The control algorithm obtained by the design, must be implemented as real-time control software, to be executed on the industrial PC. For a fast and easy translation from design to real-time application, a new software tool has been developed. This tool generates directly C++ code, easy to compile, from a graphical description of the control. With this tool, the experiments have been achieved in short time. During experiments, several non expected circumstances appear, but this was not a problem: the tool allows for an easy improvement of the original design. The paper describes the tool and its use during experiments.
Frequency-domain analysis for prediction of seasickness on ships
(Marine Technology and Sname News, 2005) Esteban San Román, Segundo; Girón Sierra, José María; Recas Piorno, Joaquín; Cruz García, Jesús Manuel de la
Oscillatory vertical motions of ships cause seasickness. There is a mathematical model that can be used to compute the percent of passengers who will get sick caused by vertical motions, However, the application of the mathematical model requires obtaining 2 hours of records of experimental or simulated ship motion data. Based on a filters analogy, this article proposes a new frequency-domain method for the calculation of seasickness incidence. The method can be applied to any sea power spectrum and any ship. Because it is based on response amplitude operators or transfer functions, which can be obtained with seakeeping simulation programs, the method can be applied even before the ship is built. The results of the method can be useful for ship design and for the analysis of best operation for passenger comfort.
Signal conditioning for the Kalman filter: application to satellite attitude estimation with magnetometer and sun sensors
(Sensors, 2016) Esteban San Román, Segundo; Girón Sierra, José María; Angulo, Manuel
Most satellites use an on-board attitude estimation system, based on available sensors. In the case of low-cost satellites, which are of increasing interest, it is usual to use magnetometers and Sun sensors. A Kalman filter is commonly recommended for the estimation, to simultaneously exploit the information from sensors and from a mathematical model of the satellite motion. It would be also convenient to adhere to a quaternion representation. This article focuses on some problems linked to this context. The state of the system should be represented in observable form. Singularities due to alignment of measured vectors cause estimation problems. Accommodation of the Kalman filter originates convergence difficulties. The article includes a new proposal that solves these problems, not needing changes in the Kalman filter algorithm. In addition, the article includes assessment of different errors, initialization values for the Kalman filter; and considers the influence of the magnetic dipole moment perturbation, showing how to handle it as part of the Kalman filter framework.
Improving fast-ship seakeeping using several moving actuators
(Naval Architect, 2005) Esteban San Román, Segundo; Recas Piorno, Joaquín; Girón Sierra, José María; Cruz García, Jesús Manuel de la; Riola, M.
Fast ships models for seakeeping improvement studies using flaps and T-foil
(Mathematical and Computer Modelling, 2005) Esteban San Román, Segundo; Girón Sierra, José María; Andrés Toro, Bonifacio de; Cruz García, Jesús Manuel de la; Riola, M.
Fast ships are taking a relevant role with a clear interest for military purposes. Fast sea transportation encounters several problems to be solved. This article refers to the difficulties originated by brisk vertical motions. The waves encountered by fast ships induce such vertical motions, and this has negative effects: navigation risks, sea sickness, structural damages, and load displacement. It is also interesting for military uses to stabilize the ship when an aircraft is landing or when precision firing is required. By means of submerged actuators, it is possible to alleviate vertical motions. In this research, a pair of transom flaps and a T-foil near the bow are used to counteract the waves. These actuators must move with the maximum efficiency, taking into account the dynamical characteristics of the ship. As a consequence, there is a problem of automatic control design. To carry out this design, it is important to obtain mathematical models of all the aspects involved in the problem: the ship, the waves, the actuators, and the effect on crew and comfort. The aim of this paper is to present the development of these models and the use of them for problem analysis and control design.