Arquitectura de control para vehículos solares autónomos de superficie para aguas someras en misiones de larga duración

Laburpena

ABSTRACT The world's seas are a valuable resource, as well as a key element in the ecology and sustainability of the environment, needing protection as an important source of food, wealth and life. The successful management of marine resources is achieved by monitoring the physical-chemical parameters related to water quality, such as salinity, temperature, dissolved oxygen, nitrates, phosphates, density, pH and levels. chlorophyll, among others. To correctly monitor the parameters of the water quality of the marine environment, a control architecture for an autonomous surface vehicle ASV is proposed in this thesis to carry out long-duration missions that can be anchored on shallow waters and behave as a fixed buoy to optimize the energy of the mission, what has been called in this thesis hybrid behavior ASV-Buoy. This vehicle is self-sufficient with photovoltaic solar energy and incorporates specialized detection systems to measure water quality. This joint robotic system has been called the robotic oceanographic observatory. The system is a combination of an autonomous vehicle and a fixed buoy, whose energy and navigation autonomy are managed thanks to a software architecture capable of making intelligent and autonomous decisions. This highly specialized vessel is novel because it has the ability to anchor itself to the seabed and become a "buoy", either to take measurements at specific points or to recharge its batteries and navigate exploring a certain area taking samples of the environment. The control architecture designed is of a hybrid type, which combines a deliberative layer divided into two levels, the Strategic Level and the Tactical Level, which are the decision-makers, and a reactive layer, the Operational Level, where reactive behaviors are executed. Of the studies of autonomous vehicles that have been described in the literature, such as remotely operated vehicles (ROV), autonomous underwater vehicles (AUV) and autonomous surface vehicles (ASV), all have limited autonomy of energy supply Due to the capacity of their batteries, therefore, the area that they can cover is also important. They do not have systems for the production and intelligent management of their energy, which make it possible to optimize their use in long-term missions, and to adequately plan the areas to be monitored. This ASV-Buoy provides a novel solution and achieves a permanent autonomous presence in lakes or shallow coastal waters. This improves autonomy in the monitoring of water quality parameters and avoids the problems associated with the deployment of a large number of marine observation systems based on fixed buoys, which influence and affect maritime traffic, the environment, tourism. and the cost involved. All vessel operations are managed by the control architecture implemented in the vehicle. The decision-making system calculates the route to the next area to be explored taking into account a series of parameters, including: the position of the vehicle, the physico-chemical parameters of the water, the distance to the next exploration area, the solar radiation, the energy available in its batteries, wind speed and direction, water currents, etc. The thesis contemplates the design and simulation of the control architecture model using Matlab / Simulink software, to verify its viability, introducing data similar to those obtained in the real world. A strategy for classifying georeferenced exploration zones is proposed to facilitate decision-making on the viability of the exploration route. For this purpose, the exploration area (in this thesis the Mar Menor) is divided into georeferenced grids, establishing a database of the coordinates of each area, in order to have clearly differentiated and ordered the values of the physical-chemical parameters of each area, when the scans are carried out. A permanent monitoring mission in the Mar Menor is also described, with a combination of photovoltaic harvesting solar-power and a decision-making strategy regarding the optimal route to follow. At the end, the results of the mission and energy simulation are included, as well as a description of the actual monitoring missions obtained in the experiment carried out. The deployment of several of these robots to explore a certain marine area is proposed for future research.