Research projects.

Control of Gyro-stabilized Platforms (CPG)

Summary:
The objective of this project is studying the control problem of gyro-stabilized platforms, providing specific solutions for its implementation. The work group is formed upon a number of Automatic Control Specialists, Mathematicians and Mechanics Specialists. The Firsts, are concerned to propose the control strategies to be applied, the seconds analyze the outcome results and behaviours and the thirds are concerned to give assistance in proper aspects of its speciality.

The control of Platforms is a complex problem due, essentially, to friction and gear backlash phenomena, which extraordinarily complicate the high-performance control in position required by such systems.

The most outstanding techniques available nowadays (Hamiltonian Systems, LuGre-modelling for friction, gear backlash modelling) are employed in order to give appropriate solution to the problem.
The proposed techniques are to be tested in a platform manufactured by FABA Inc. (see picture), in which several gyroscopes are installed. A mobile base is also employed to test disturbance performance of the system.

This project is a continuation of previous works carried out by the Project Research Teams, in collaboration with the enterprise, which promotes and supervises the project.

Robust Control of Industrial Robots (CRI)

Summary:
The objective of this project is to try to provide specific solutions to robot control. For this, robust control techniques will be applied to the direct control of individual joints.

The results are being applied to the control of an industrial robot (RM10, see picture above), to be compared to the conventional control currently in use. The project is aimed at developing of high performance robots, more rapid and accurate in different working situations.

Currently, controllers based on feedback linearization techniques, as well as some others taking into account the global non-linear nature of the system are being tested. Uncertainties in the model are to be considered in the outer loop linear robust controller.
Efforts will focus in the development of controllers based on the LTR, H_2 and H_\infty methodologies, as well as in combined approaches LTR-H_\infty.
The presence of saturations and the multivariable character of the robot system will be take into account in all cases.

For the execution of this project, the industrial controllers of the RM10 robot have been substituted. The new controller is based on a DSpace's card in which all the parts of the controller are to be implemented.

Pilot Plant for Control and Supervision of an Adsorption Solar Refrigerating Machine

Summary:
One of the most interesting applications of Solar Energy is cold production from the sun, because refrigeration is obviously more needed when solar radiation is highest, hence temperatures are the highest too.

In Andalusia, the weather conditions make the use of this technology very convenient, and some University Research Groups have been interested in it during the last few years. Particularly interesting are Adsorption Refrigerating Machines, which as it's well known produce cold from a heat source in its generator. This heat can be provided in many different ways, being one of them Solar Radiation.

Previous studies took to the knowledge of the situation and were clear the viability and great possibilities of these systems. Additionally, since conventional energy (from Nuclear or Coal Fired Plants, for instance) is not employed in the process, Environmental impact associated to greenhouse gases emissions and others are reduced.

The Institutes of Automatics, Robotics and Renewable Energies in Andalusia, were able to find financial support for the installation of an Adsorption Refrigerating Solar Plant with a supporting gas boiler. The Plant is currently installed in the roof of the Laboratories Building of the Superior School of Engineers of the University of Seville.
The installation has been designed and constructed so that it allows the test of the contribution and consumption subsystems, jointly or separately, in an automatization and control context that can allow the optimization of the assembly.

Two Phase Olive-Cake Dryer Systems: Design, Control and Energetic Optimization (SECORU)

Summary:
The modern "two phase " olive-oil mills generate a waste called "alpeorujo" or "two phase cake", that has to be dried before feeding it into the leaching system in order to extract the remaining oil. The problems created by "alpeorujo", during the drying process are different from those caused by traditional "three-phase" olive cake. This has led to serious operational problems (blockage, fires, low thermal efficiency) and is forcing oil producers to improvise changes in their drying systems. The high degree of humidity in alpeorujo (65%) means that energy optimization is a key aspect.

In this context, the project’s two main objectives are to identify the design and operation standards of rotary dryers for "two-phase" olive cake and to develop an automatic system to optimize the control of the drying process. The project’s application is guaranteed because it meets a real and urgent need in this important industrial sector in Andalusia.

In our laboratories of the Superior School of Engineers there is a drying installation (see picture above), with a distributed control system that allows the control and integral monitoring of the dryer.

Solar Thermal Central Receiver Systems (SIREC)

Summary:
The aim of the project is to facilitate the market penetration of solar thermal central receiver systems. This main goal is to be achieved according to the following objectives:

Significant improvement of global profitability of solar thermal power plants using central receivers, through a cost reduction of the main system components like receiver and heliostats, and the simplification of associated O&M.
Better integration of central receiver systems into thermal power plants by developing advanced components able to promote more efficient schemes of hybridization. Adaptation of advanced components to solar stand-alone applications and plants with the highest efficiency.
To promote the development and consolidation of a national industry, through technology transfer, elaboration of feasibility studies and definition of actions aiming to remove non-technological barriers for the eventual deployment of the technology.

Regarding heliostats, the objective is to develop low-cost heliostat based on national technology, with a dramatic reduction of manufacturing costs (about 40 %), lightweight and modular structure, easy transportation, installation and canting, and an integrated control system with the potential to introduce wireless communications. The project encompasses the design, construction and testing of several prototypes at the Plataforma Solar de Almeria, and eventually the test of a limited series to get availability figures based on statistical treatment of O&M data.
Regarding the receiver, an advanced volumetric receiver would be developed, as it is considered the key component where centralization of collected solar radiation takes place. Receiver development will be structured according to the following criteria: High flux receiver (2 MW/m2) with a more compact design, operation at higher temperatures (1000 ºC), with a ceramic matrix, selfregulation system to adjust air recirculation flowrate through the receiver and local values of solar concentrated flux distribution, and also with a modular design for cold air recirculation, specifically conceived for the new receiver. The project includes the development of one prototype with a nominal thermal power of about 500 kW to be tested at the "Plataforma Solar de Almeria".
The project will be completed with a conceptual design of a demonstration plant and with a technical and economical feasibility study. The organization is through a Co-ordinated Project with participation of two Public R&D Centers (IAER and CIEMAT-PSA), one industry (INABENSA), and the University of Sevilla, all of them located in the Region of Andalusia (Spain).

Development of the Servo Controllers for a Sensors Pedestal. (CSPS)

Summary:

The objective of this project is the design and implementation of a controller in order to stabilize a pedestal on a ship, as well as its integration in a tracking system. Robust and nonlinear control techniques are been applied to control both pedestal motors. The Pedestal can operate in the following modes: position control, on board velocity control and inertial velocity tracking. Controllers for these operation modes have been developed. Furthermore, two simulators are being under development: the first one models the mechanical part of the pedestal while the second one simulates the closed-loop system in order to be integrated in a local network of simulators which will be used in on-ground tests. This project is founded by the BAZAN company.

Pedestal control for high-precision solar tracking (IFICLES)

Summary:

The objective of this project is the design and implementation of a controller for a sun tracker pedestal, which will have high-concentration photovoltaic panels that need higher precision than conventional photovoltaic panels. It is for this reason that the problem will be approached using a solar tracking strategy that will be adjusted to the system angular opening and its later implementation in the real system. Furthermore, energy saving considerations have to be taken into account. The resultant strategy will be validated by means of simulation and by tests on a tracking pedestal. This project is founded by the INSPIRA company.