Day

octubre 3, 2013

Composite material pedestrian bridge for the Port of Bilbao

IOP Conf. Series: Materials Science and Engineering 40 (2012) 012040. I. Gorrochategui, C. Manteca, A. Yedra, R. Miguel and F. J. del Valle Abstract: Composite materials in comparison to traditional ones, steel and concrete, present advantages in civil works construction: lower weight, higher corrosion resistance (especially in the marine environment), and ease of installation. On the other hand, fabrication costs are generally higher. This is the reason why this technology is not widely used. This work illustrates the process followed for the design, fabrication and installation of a composite material pedestrian bridge in the Port of Bilbao (Northern Spain). In... Read More

Linear quadratic control application for a 4 axis optronic gyroestabilized platform

This article presents a design of a linear quadratic regulator (LQR) for an electro mechanic 4 axis gyroestabilized system, used as a optronic observation turret. Embebed stabilized platforms with multigimbal architectures represent a non linear multivariable control problem, which in the case of optronic turrets demands the accomplishing of very strict requirements from the regulator. LQR regulators, apart from solving the control problem in an optimal way, provide an important tolerance in case of perturbances. With this purpose, cinematic and dynamic models of an observation optronic turret have been obtained in advance. These models, after being initialize, have been used... Read More

APLICACIÓN DEL CONTROL CUADRÁTICO LINEAL A UNA TORRETA OPTRÓNICA GIROESTABILIZADA DE 4 EJES

XXII Jornadas de Automática. Sevilla, España,  7-9 septiembre, 2011  Alberto Puras, José Ramón Llata  Resumen: En este artículo se presenta el diseño de un regulador cuadrático lineal LQR para un sistema electromecánico giroestabilizado de 4 ejes utilizado como torreta optrónica de observación. Las plataformas estabilizadas embarcadas de arquitectura multigimbal constituyen un problema de control multivariable no lineal, que en el caso de las torretas optrónicas exige además el cumplimiento de requisitos muy exigentes al regulador. Los reguladores LQR, además de resolver el problema de control de forma óptima, aportan una importante tolerancia ante posibles perturbaciones. Para ello se han obtenido... Read More

Nonlinear Optimal Line-Of-Sight Stabilization with Fuzzy Gain-Scheduling

World Academy of Science, Engineering & Technology; August 2011, Issue 56, p23  Alberto Puras, José Ramón Llata  Abstract: A nonlinear optimal controller with a fuzzy gain scheduler has been designed and applied to a Line-Of-Sight (LOS) stabilization system. Use of Linear Quadratic Regulator (LQR) theory is an optimal and simple manner of solving many control engineering problems. However, this method cannot be utilized directly for multigimbal LOS systems since they are nonlinear in nature. To adapt LQ controllers to nonlinear systems at least a linearization of the model plant is required. When the linearized model is only valid within the... Read More

ATTITUDE DETERMINATION FROM GPS SIGNALS

9th International Conference Computational And Mathematical Methods In Science And Engineering. Gijón, June 30, July 1-3, 2009. Alejandro P. Nicolás, Laureano González-Vega, Michael González Harbour, Raúl Arnau, Daniel Bolado, María Campo-Cossío, Alberto Puras  Abstract: The aim of this work is to design an efficient algorithm for attitude determination using data from non-dedicated GPS receivers. So, we compare two different methods. They use L1carrier phase-double differences obtained from real GPS signals. The first one provides an instantaneous estimation of the attitude reducing the ambiguity search space. However, it is very sensitive to experimental errors. The second one exploits the redundancy of... Read More

Attitude determination from GPS signals

9th International Conference Computational And Mathematical Methods In Science And Engineering. Gijón, June 30, July 1-3, 2009.  Alejandro P. Nicolás, Laureano González-Vega, Michael González Harbour, Raúl Arnau, Daniel Bolado, María Campo-Cossío, Alberto Puras Abstract: The aim of this work is to design an efficient algorithm for attitude determination using data from non-dedicated GPS receivers. So, we compare two different methods. They use L1carrier phase-double differences obtained from real GPS signals. The first one provides an instantaneous estimation of the attitude reducing the ambiguity search space. However, it is very sensitive to experimental errors. The second one exploits the redundancy of... Read More

Real-time attitude determination system based on GPS and aided by low-cost inertial sensors

13th IAIN world congress and exhibition. Stockholm, Sweden, October 27-29, 2009.  María Campo-Cossío, Alberto Puras, Raúl Arnau, Daniel Bolado  Abstract: This paper explores a low-cost GNSS attitude determination solution based on L1 GPS receivers with the aiding of MEMS gyroscopes. The proposed approach resolves integer ambiguity on-the-fly using single frequency carrier phase measurements overcoming the problems of reliability, availability and performance present in high dynamic environments in common low-cost GNSS attitude determination systems. For high-precision GPS-based attitude determination reliable integer ambiguity resolution (IAR) has been a critical issue, being performance and computational efficiency of the ambiguity search process its main... Read More

MULTI-GNSS Receivers/IMU System Aimed at the Design of a Heading-Constrained Tightly-Coupled Algorithm

ICL-GNSS 2013 International Conference on Localization and GNSS. Turin, Italy, June 25-27, 2013.  Gianluca Falco, María Campo-Cossío, Alberto Puras  Abstract: This paper presents the design of a truly low-cost multi-GNSS receivers /IMU navigation system that exploits the benefits of GNSS technology in attitude determination. The sensor package of the system consists of 4 single chipset receivers, 4 antennas, and one low grade MEMS IMU. Both parts, the GNSS and the IMU ones, are integrated by following a heading-constrained Tightly-Coupled approach, where inertial and GNSS raw measurements as well as GNSS computed heading are blended into an Extended Kalman Filter. To... Read More

Reactive Navigation and Online SLAM in Autonomous Frontier-Based Exploration

5th IWINAC 2013: International Work-Conference on the Interplay Between Natural and Artificial Computation, Mallorca, Spain, June 10-14, 2013. Raúl Arnau Prieto, José Manuel Cuadra Troncoso, José Ramón Álvarez Sánchez, Israel Navarro Santosjuanes Abstract: This paper describes an autonomous exploration algorithm for mobile robots. The method implements a frontier-based exploration strategy that relies on a reactive navigation system and a SLAM algorithm. Despite its strong biological inspiration, the navigation method is especially well suited for the exploration task since it is able to accept and follow higher level position targets while guaranteeing the integrity of the robot. The SLAM module is intended for online... Read More