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ARE THE ONLY NATIVE VASCULAR SPECIES OF PLANTS IN THE ANTARCTICREGION AND ARE A SOURCE OF INTEREST IN THE CLIMATE CHANGE STUDIES.THESE PLANTS HAVE BEEN STUDIED FOR DECADES AND RECOGNIZEDAS BIOINDICATORS OF THE CLIMATE CHANGE. THE ARTICLE PRESENTSPRELIMINARY STUDIES AND RESULTS OF A THERMAL ACTUATOR, WHICH ISGOING TO BE APPLIED IN A CLIMATE CHANGE STUDIES. THE ELABORATED,FAR INFRARED ACTUATOR TOGETHER WITH A CONTROL SYSTEM MAINTAINSTHE TEMPERATURE OF THE ANTARCTIC PLANT CERTAIN DELTA ABOVE THEAMBIENT TEMPERATURE. SINCE THE HEAT TRANSFER IS BASED ON INFRAREDRADIATION A THERMAL MODEL IS INTRODUCED, WHERE THE PARAMETERSOF THE MODEL ARE DETERMINED EMPIRICALLY APPROXIMATING IT USING A1-ST ORDER DYNAMICAL SYSTEM. ONCE DETERMINED, THE SYTEM MODELPAREMETERS HELP TO DESIGN THE CONTROL STRATEGIES: CONTROL ON-OFF(1) AND CONTROL PID (PROPORTIONAL?INTEGRAL?DERIVATIVE) (2). ASA RESULT WE OBTAIN THAT THE CONTROL PID MAINTAINS THE OBJECTSTEMPERATURE WITH MAJOR STABILITY THAN ON-OFF, WHAT MAKES ITPREFERABLE IN THE ?NAL APPLICATION. THE FUTURE WORKS INVOLVEMODELING AMBIENTAL PERTURBATION, WHICH AFFECTS THE SYSTEM ANDDETERMINATION THERMAL PARAMETERS OF THE ANTARCTIC PLANTS.

COLOBANTHUS QUITENSIS AND DESCHAMPSIA ANTARTICA ARE THE ONLY NATIVE VASCULAR SPECIES OF PLANTS IN THE ANTARCTIC REGION AND ARE A SOURCE OF INTEREST IN THE CLIMATE CHANGE STUDIES. THESE PLANTS HAVE BEEN STUDIED FOR DECADES AND RECOGNIZED AS BIOINDICATORS OF THE CLIMATE CHANGE. THE ARTICLE PRESENTS PRELIMINARY STUDIES AND RESULTS OF A THERMAL ACTUATOR, WHICH IS GOING TO BE APPLIED IN A CLIMATE CHANGE STUDIES. THE ELABORATED, FAR INFRARED ACTUATOR TOGETHER WITH A CONTROL SYSTEM MAINTAINS THE TEMPERATURE OF THE ANTARCTIC PLANT CERTAIN DELTA ABOVE THE AMBIENT TEMPERATURE. SINCE THE HEAT TRANSFER IS BASED ON INFRARED RADIATION A THERMAL MODEL IS INTRODUCED, WHERE THE PARAMETERS OF THE MODEL ARE DETERMINED EMPIRICALLY APPROXIMATING IT USING A 1-ST ORDER DYNAMICAL SYSTEM. ONCE DETERMINED, THE SYTEM MODEL PAREMETERS HELP TO DESIGN THE CONTROL STRATEGIES: CONTROL ON-OFF (1) AND CONTROL PID (PROPORTIONAL?INTEGRAL?DERIVATIVE) (2). AS A RESULT WE OBTAIN THAT THE CONTROL PID MAINTAINS THE OBJECTS TEMPERATURE WITH MAJOR STABILITY THAN ON-OFF, WHAT MAKES IT PREFERABLE IN THE FINAL APPLICATION. THE FUTURE WORKS INVOLVE MODELING AMBIENTAL PERTURBATION, WHICH AFFECTS THE SYSTEM AND DETERMINATION THERMAL PARAMETERS OF THE ANTARCTIC PLANTS.

THE USE OF NUMERICAL MODELS IN THE AGRICULTURAL INDUSTRY IS BECOMING MORE COMMON TO SOLVE DIFFERENT ISSUES, FOR EXAMPLE DESIGN OPTIMIZATION OR MODEL BASED CONTROL DESIGN. NEVERTHELESS, SUCH NUMERICAL MODELS ARE COMPUTATIONALLY EXPENSIVE AND IMPRACTICAL FOR CONTROL DESIGN. THIS WORK SHOWS A METHODOLOGY FOR OBTAINING A REDUCED ORDER MODEL THAT PREDICTS THE THERMAL BEHAVIOR OF A GREENHOUSE, IN ORDER TO DESIGN CONTROL SYSTEMS TO REGULATE THE BEHAVIOR OF THE INTERNAL MICROCLIMATE OF GREENHOUSES. THIS MODEL IS OBTAINED THROUGH SYSTEM IDENTIFICATION APPLIED TO THE DATA OBTAINED FROM A NUMERICAL GREENHOUSE (NG), MODELLED USING COMPUTATIONAL FLUID DYNAMICS (CFD) THROUGH ANSYS FLUENT 2019R3 SOFTWARE. THE CFD MODEL IS EXPERIMENTALLY VALIDATED BY COMPARING THE TEMPERATURE DISTRIBUTION INSIDE THE GREENHOUSE WHEN TURNING ON AND OFF A SET OF FANS, OBTAINING A 1.28% ROOT MEAN SQUARE ERROR. SUBSEQUENTLY, NUMERICAL SIMULATIONS OF TURNING ON AND OFF OF FANS ARE CARRIED OUT TO OBTAIN TEMPERATURE DATA AND TO OBTAIN A MODEL THAT RELATES THE ON TIME WITH THE AVERAGE TEMPERATURE INSIDE THE GREENHOUSE. DIFFERENT STRUCTURES WERE USED IN THE IDENT TOOL OF MATLAB, WHERE THE BEST FIT WAS FOUND FOR A SIMPLE LINEAR FUNCTION WITH DELAY WITH 61% OF RELATION TO THE SIMULATED DATA FROM THE NG AND 62% WHEN COMPARED WITH EXPERIMENTAL DATA.

THE PRESENT WORK PRESENTS THE STATE OF ART REVISION FOR THE CHILEAN LEGISLATION, NORMS AND GUIDES TO CARRY OUT A PHOTOVOLTAIC INSTALLATION AT THE UNIVERSIDAD DEL BÍO-BÍO. THE CHILEAN SOLAR POTENTIAL WITH RESPECT THE REST OF THE WORLD, HIGH-LIGHTING CHILE AS THE WORLD LEADER IN SOLAR RESOURCE AVAILABILITY, WITH THE HIGHEST RADIATION RATES, EVEN BIGGER THAN COUNTRIES AS GERMANY, SPAIN, CHINA, UNITED STATES, WHICH HAVE A SIGNIFICANT AMOUNT OF PHOTOVOLTAIC (PV) ENERGY INSTALLED. TO ATTAIN A PV INSTALLATION IT IS NECESSARY TO CARRY OUT AN ENERGY CONSUMPTION STUDY, CONSIDERING THE INVOICES OF THE ELECTRICAL CONSUMPTION AND THE DAILY CONSUMPTION CURVE, IN ORDER TO DIMENSION THE NUMBER OF PV MODULES TO BE INSTALLED. IN ADDITION, THE PV CURVES ARE STUDIED TO EXTRACT THE MAXIMUM POWER FROM THE PV MODULES BY THE USE OF ALGORITHMS CAPABLE TO WORK INTO THE WHOLE SYSTEM OPERATING REGION, OPTIMIZING THE ENERGY INJECTION TO THE GRID AND/OR BATTERIES. FINALLY, AN ECONOMIC STUDY IS PRESENTED WHERE ECONOMICS TOOLS SUCH AS THE NET PRESENT VALUE (NPV) AND INTERNAL RATE OF RETURN (IRR) ARE EMPLOYED TO SHOW THIS PROJECT FEASIBILITY.

THE DESIGN OF ACCURATE CONTROL SYSTEM CAN TAKE A LOT OF EFFORT, ESPECIALLY WHEN ITS DYNAMICS ARE FAIRLY COMPLEX OR UNKNOWN AND A DESIRED OUTCOME IS CRITICAL. TO ESTIMATE THE REAL PARAMETERS OF THE DYNAMIC MODEL, THE LEAST SQUARES ESTIMATION METHOD CAN BE USED, EVEN FOR NONLINEAR SYSTEMS USING THE INPUT AND OUTPUT MEASUREMENTS. THE TIME DIFFERENTIAL EQUATION OF NONLINEAR MODEL CAN BE LINEARIZED TO OBTAIN THE TRANSFER FUNCTION IN THE FREQUENCY DOMAIN. THUS, IT IS POSSIBLE TO ADJUST THE CONTROLLER GAINS BASED ON THE ONLINE PARAMETERS ESTIMATION TO GET AN ACCURATE CONTROLLER CONTEMPLATING REAL SYSTEM CONSTANTS. IN THIS WORK, BOTH, THE ESTIMATION METHOD AND ADAPTIVE CONTROL METHOD ARE TESTED USING THE REMOTE LABORATORY SLD-UBB (REMOTE LABORATORY SYSTEM OF THE UNIVERSIDAD DEL BÍO-BÍO).

THIS PAPER PRESENTS THE COMPARISON BETWEEN THREE CONTROL STRATEGIES: A PID BASED CONTROL, THE GAINS SCHEDULE PID BASED CONTROL AND A COMBINATION OF PID AND STATES FEEDBACK BASED CONTROL FOR A DC-DC POWER CONVERTER. THE DC-DC CONVERTER IS USUALLY EMPLOYED ON RENEWABLES ENERGIES TO PUMP THE VOLTAGE UP TO STANDARD VALUES ON THE GRID COUPLE POINT, WHICH IN THE CASE OF CHILE IS 220V RMS AND 50HZ; OR TO BE USED ON VOLTAGE REGULATORS, WHICH NEEDS TO MAINTAIN THE VOLTAGE TRACKING A REFERENCE INDEPENDENTLY OF THE INPUT VOLTAGE SUPPLY. THE MAIN OBJECTIVE IS TO ACHIEVE CONTROLLABLE SYSTEM INTO THE WHOLE POWER CONVERTER OPERATING REGION, WITH SIMILAR DYNAMIC RESPONSES. TO CORROBORATE THE MATHEMATICAL STUDY AND THE PROPOSED DESIGN, SIMULATIONS TESTS WERE PERFORMED IN SIMULINK/MATLAB ENVIRONMENT SHOWING EVERY STRATEGY STRENGTHS TO FAIRLY COMPARE THE RESULTS UNDER DISTURBANCES AND REFERENCES CHANGES.

EN ESTE TRABAJO, SE DESCRIBE LA IMPLEMENTACIÓN DE UNA PLATAFORMA DE PRUEBAS PARA UN SISTEMA DE INSPECCIÓN DE PLANTAS DE ARÁNDANOS BASADO EN UN DRON CON CÁMARAS MULTIESPECTRALES. EL OBJETIVO PRINCIPAL ES IMPLEMENTAR, EN UN ROBOT UR3E, EL SEGUIMIENTO DINÁMICO DE TRAYECTORIAS COMANDADAS POR UN SISTEMA DE VISIÓN INCORPORADO EN SU EFECTOR FINAL, QUE PERMITA PROBAR Y EVALUAR DIVERSAS ALTERNATIVAS DE ESCANEO, DETECCIÓN E INSPECCIÓN DE LOS RACIMOS DE ARÁNDANOS EN LAS PLANTAS, QUE SERÍAN IMPLEMENTADAS POSTERIORMENTE EN EL DRON. PARA REALIZAR EXPERIMENTOS, SE COLOCARON IMÁGENES DE RACIMOS DE ARÁNDANOS, EN PEQUEÑNOS POSTES DE MADERA, QUE SE UBICARON EN EL ESPACIO ACCESIBLE POR EL UR3E. CUANDO EL ROBOT SE ACCIONA, COMIENZA A MOVER LA CÁMARA HASTA DETECTAR LOS FRUTOS, GUARDA UN VIDEO DE LA INSPECCIÓN DEL RACIMO, Y CONTINÚA SU TRAYECTORIA EN BUSCA DE MÁS FRUTOS. LOS RESULTADOS DE ESTAS PRUEBAS PERMITIERON ESTABLECER EL RANGO DE MOVIMIENTOS NECESARIOS PARA CAPTURAR IMÁGENES REPRESENTATIVAS DE LAS PLANTAS DE ARÁNDANOS, ESTABLECER Y VALIDAR LA COMUNICACIÓN ROBUSTA ENTRE LOS DISPOSITIVOS INVOLUCRADOS EN EL SISTEMA DE INSPECCIÓN Y CORROBORAR LA EFECTIVIDAD DEL MODELO DE DETECCIÓN DE ARÁNDANOS.