IN THIS PAPER ARE SHOWN AND COMPARED TWO CONTROL STRATEGIES APPLIED TO A PARALLEL ROBOT OF THREE DEGREES OF FREEDOM DERIVED BY ELECTRO-PNEUMATIC ACTUATORS WITH PROPORTIONAL FLOW VALVES. ROBUST CONTROL IS IMPLEMENTED WITH A CLASSICAL PI CONTROL WITH A SECOND-ORDER COMPENSATOR FILTER; THIS IS A GOOD POSITION AND TRACKING CONTROLLER BUT IS NOT A SAFETY CONTROL IN TERMS OF HUMAN INTERACTION. MEANWHILE, A PROXY-BASED SLIDING MODE CONTROL IS IMPLEMENTED COMBINING THE ADVANTAGES OF SLIDING MODE CONTROL AND PROPORTIONAL INTEGRAL DERIVATIVE CONTROL. ALL THE RESULTS ARE OBTAINING IN CO-SIMULATION BETWEEN ADAMS AND MATLAB AND IN A REAL PLATFORM.

HIGH ENERGY DEMAND HAS CREATED MANAGEMENT AND ORGANIZATIONAL PROBLEMS IN MANY COUNTRIES AROUND THE WORLD. THE WORLD IS EXPERIENCING A CRISIS THAT DRIVES US TO TAKE ACTION AND CONTRIBUTE TO NEW DEVELOPMENTS AND RESEARCH TO INFLUENCE THE ENERGY TRANSITION THROUGH A COMBINATION OF CONTROL STRATEGIES TO IMPROVE THESE PROCESSES. THIS PROMOTES THE USE OF NON- CONVENTIONAL RENEWABLE ENERGY TO SUSTAIN LIFE AND PROMOTES SUSTAINABLE AND EFFICIENT PROCESSES. THE IMPORTANCE OF DEVELOPING NEW APPLICATIONS, USING NEW TECHNOLOGIES, AND DESIGNING APPROPRIATE CONTROLS TO OPTIMIZE PROCESSES THAT REQUIRE ENERGY CONVERSION. THE FOCUS OF THIS WORK IS THE DESIGN, SIMULATION, AND IMPLEMENTATION TESTING OF AN OPTIMAL CONTROL IN THE MULTILEVEL NEUTRAL POINT CLAMPED (NPC) TOPOLOGY. THE PROPOSED CONTROL, BY USING AN OPTIMAL STATE FEEDBACK BASED ON THE LINEARIZED MODEL OF THE CONVERTER, ALLOWS TO OPTIMIZE THE USE OF ENERGY IN THE REFERENCE VARIATIONS. THE RESULTS SHOW THE CORRECT CURRENT CONTROL, FOLLOWING THE REFERENCES IMPOSED BY THE POWER CONTROL WITH SPECIFIC DYNAMIC AND OVERSHOOT, INCLUDING THE DC LINK CAPACITORS UNBALANCING COMPENSATION.

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.

SOLAR ENERGY IS AN INTERESTING ALTERNATIVE TO SUPPLY THE GROWING ENERGY REQUIREMENTS FROM INDUSTRIES AND HOMES. IN FACT, MANY RESEARCHERS HAVE PUT EFFORT TO MAXIMIZE THE SOLAR SYSTEM EFFICIENCY. THIS PAPER, MAKE A COMPARISON BETWEEN THREE ALTERNATIVES OF MAXIMUM POWER POINT TRACKING ALGORITHMS (MPPT) TO INJECT THE MAXIMUM POWER TO THE GRID. THE PROPOSAL INCLUDES ONLY A THREE-PHASE INVERTER AVOIDING THE DC-DC CONVERTER AND THEREFORE THE CONTROL IS PERFORMED THROUGHOUT THE DC LINK VOLTAGE REFERENCE. THE COMPARISON INCLUDES THE TOTAL TIME TO COMPUTE EVERY ALGORITHM WHERE THE TMS320F28335 DSP BASED BOARD IS EMPLOYED. ON THE OTHER HAND, THE THREE-PHASE POWER CONVERTER IS CONTROLLED THROUGH NONLINEAR BASED CONTROL WHICH DECOUPLES AND LINEARIZES THE CURRENT RESPONSE. THE RESULTS GIVE KEY LINES TO DECIDE THE PROPER MTTP ALGORITHM CONSIDERING THE PROCESSING TIME AND THE DESIRED PERFORMANCE.

MAXIMUM POWER POINT TRACKING (MPPT) METHODS HAVE BEEN WIDELY DISCUSSED IN MANY RESEARCHES TO IMPROVE THE EFFICIENCY OF THE ENERGY EXTRACTION FROM SOLAR CELLS. ON THE OTHER HAND, TO CONTROL PROCESS THE MOST COMMON WAY IS TO FIND A MODEL, WHERE THE PARAMETERS ARE ADJUSTED IN ORDER TO ACHIEVE SIMILARITY BETWEEN THE MODEL AND THE REAL PLANT. SOLAR CELLS HAVE BEEN MODELED BY NONLINEAR EQUATIONS THAT ALLOW TO APPROXIMATE THE STATIC BEHAVIOR. HOWEVER, THE PARAMETERS EVOLVED IN THESE EQUATIONS DEPEND UPON THE CONSTRUCTION AND THE TYPE OF SOLAR CELLS. THUS, THIS PAPER PROPOSES A PARAMETER IDENTIFICATION WITH A NEW SIMPLIFIED METHOD TO IDENTIFY THE PARAMETERS N, RS AND I0, BY STUDYING AND ANALYZING THE EQUATIONS OF THE PV MODEL AND THE INFORMATION PROVIDED BY THE DATASHEETS OF THE BEST-SELLING COMMERCIAL PV PANELS IN THE WORLD.

CONTROL OF POWER CONVERTER IS BEING WIDELY STUDIED TO PROPERLY MANAGE THE VARIABLES AND CONVERT THE ENERGY TO REACH THE SETTLED GOALS. PARTICULARLY, THE INSERTION OF RENEWABLE ENERGIES ON THE AC MAINS HAVE FOCUSED THE ATTENTION OF RESEARCHERS TO APPLIED SUITABLE CONTROL METHODS TO INJECT POWER TO THE GRID. IN THIS DOCUMENT, A NONLINEAR CONTROL STRATEGY FOR A POWER CONVERTER IS PRESENTED. THE BACK-TO-BACK TOPOLOGY ALLOWS DECOUPLING GRIDS BY USING A DC LINK BETWEEN THEM. THE ENERGY TRANSFERENCE AND THE POWER QUALITY HAVE TO BE CONTROLLED. THUS, PRIMARY CONTROLLERS HAVE TO DESIGN TO MEET CERTAIN VALUES. LOADS SENSITIVE TO VOLTAGE VARIATIONS NEED TO BE HANDLED CORRECTLY. THE PROPOSAL IS TESTED BY SIMULATION, AND THE RESULTS VALIDATE THE PROPOSAL.

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.

RYO KIKUUWE AND HIDEO FUJIMOTO INTRODUCE THE PROXY-BASED SLIDING MODE CONTROL (PSMC), WHICH IS A CONTROL ALGORITHM INTENDED FOR POSITION CONTROL OF ROBOTIC SYSTEMS. THIS PAPER IMPLEMENTS PSMC AT THE CARTESIAN SPACE OF A MOVABLE PLATFORM OF 2 DEGREE OF FREEDOM (2-DOF). NUMERICAL CO-SIMULATIONS IN MATLAB/SIMULINK ® AND MSC-ADAMS ® FRAMEWORK DEMONSTRATE THE GOOD PERFORMANCE OF THE SYSTEM IN MOTION CONTROL APPLICATION.

RYO KIKUUWE AND HIDEO FUJIMOTO INTRODUCE THE PROXY-BASED SLIDING MODE CONTROL (PSMC), WHICH IS A CONTROL ALGORITHM INTENDED FOR POSITION CONTROL OF ROBOTIC SYSTEMS. THIS PAPER IMPLEMENTS PSMC AT THE CARTESIAN SPACE OF A MOVABLE PLATFORM OF 2 DEGREE OF FREEDOM (2-DOF). NUMERICAL CO-SIMULATIONS IN MATLAB/SIMULINK ® AND MSC-ADAMS ® FRAMEWORK DEMONSTRATE THE GOOD PERFORMANCE OF THE SYSTEM IN MOTION CONTROL APPLICATION.

THIS PAPER DESCRIBES A SERIES OF EXPERIENCES IN AUTOMATION CONTROL THAT CAN BE CARRIED OUT BY USING A REMOTE LABORATORY SYSTEM IMPLEMENTED AT THE UNIVERSIDAD DEL BÍO-BÍO (UBB). REMOTE LABORATORIES ARE INCREASINGLY USED BY UNIVERSITIES TO PERFORM THE PRACTICAL ACTIVITIES, ESPECIALLY FOR CONTROL ENGINEERING EDUCATION. THIS METHOD ALLOWS USING THE LABORATORY RESOURCES MORE EFFICIENTLY, AS IT GROWTHS THE AVAILABILITY UP TO 24 HOURS A DAY, REQUIRES NO EXTRA TIME TO PRACTICE ASSEMBLE, AND ALLOWS TO SHARE EXPENSIVE RESOURCES WITH MANY STUDENTS GEOGRAPHICALLY SEPARATED FROM THE LABORATORY SETUP. THE AIM OF THIS CONTRIBUTION IS TO SHOW, WITH PRACTICAL EXAMPLES, THE POTENTIAL OF THIS METHODOLOGY APPLIED TO THE TEACHING OF AUTOMATIC CONTROL AT THE UBB WITH THE REMOTE LABORATORY SYSTEMS (?SISTEMA DE LABORATORIOS DISTANCIA?, SLD) DEVELOPED PRELIMINARILY IN THE UNIVERSIDAD CENTRAL DE LAS VILLAS, CUBA. A SCALE MODEL OF COUPLED TANKS MADE UP BY THE FEEDBACK INSTRUMENTS COMPANY WAS INCORPORATED TO THE SLD AT THE UBB. THUS, A SERIES OF LEVEL CONTROL EXPERIENCES WERE DESIGNED TO VALIDATE THE PROPORTIONAL, INTEGRAL, AND DERIVATIVE ACTIONS EFFECTS OF CLASSIC PID CONTROLLERS. IN ADDITION, EXPERIENCES TO SHOW THE NECESSITY OF SOME PRACTICAL CHANGES ON THE CLASSICAL PID WERE ALSO DEVELOPED AS SENSED VARIABLES FILTERING, ANTI-WINDUP CORRECTION, AND DERIVATIVE ACTION FILTERING.

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.