greenhouse climate controller fuzzy logic programing greenhouse climate controller using fuzzy logic...

GreenHouse Climate Controller FuzGreenHouse Climate Controller Fuzzy Logic Programingzy Logic Programing

Greenhouse Climate Greenhouse Climate Controller Using Fuzzy Controller Using Fuzzy

Logic ProgrammingLogic ProgrammingAnantharaman SriramanAnantharaman Sriraman

September 2, 2003September 2, 2003


Purpose of GHCCPurpose of GHCC

It takes care of maintaining a It takes care of maintaining a protected environment despite protected environment despite fluctuations of external climatefluctuations of external climate

It acts as a program memory, which It acts as a program memory, which can be operated by the grower as a can be operated by the grower as a tool to steer their cultivation tool to steer their cultivation


Advantages of GHCCAdvantages of GHCC

Energy ConservationEnergy Conservation Better productivity of plantsBetter productivity of plants Reduced human interventionReduced human intervention


Environmental factorsEnvironmental factors

Major FactorsMajor Factors Temperature of the Temperature of the

inside airinside air Relative humidity Relative humidity

of the inside airof the inside air SunlightSunlight

Minor FactorsMinor Factors Wind speedWind speed Wind directionWind direction Rate of Rate of

transpirationtranspiration


Control ActuatorsControl Actuators

Thermal SystemThermal System Humidification SystemHumidification System Lighting systemLighting system Thermal shade systemThermal shade system CO2 generatorCO2 generator Performance of the systemPerformance of the system


Fuzzy LogicFuzzy Logic

an alternative design methodology an alternative design methodology linear and non-linear systems for linear and non-linear systems for

control control lower development costslower development costs superior featuressuperior features better end product performancebetter end product performance market faster market faster more cost-effectivelymore cost-effectively


FuzzificationFuzzification

Measure the values of input variablesMeasure the values of input variables Performs a scale mapping that Performs a scale mapping that

transfers the range of values of input transfers the range of values of input variables into corresponding variables into corresponding universes of discourse,universes of discourse,

Performs the function of fuzzification Performs the function of fuzzification that converts input data into suitable that converts input data into suitable linguistic values, which may be linguistic values, which may be viewed as labelsviewed as labels of fuzzy sets.of fuzzy sets.


Knowledge BaseKnowledge Base

Comprises knowledge of the application Comprises knowledge of the application domain and the attendant control goals. It domain and the attendant control goals. It consists of a “database” and a “linguistic consists of a “database” and a “linguistic (fuzzy) control rule base:”(fuzzy) control rule base:”

The database provides necessary The database provides necessary definitions, which are used to define definitions, which are used to define linguistic control rules and fuzzy data linguistic control rules and fuzzy data manipulation in an FLC. manipulation in an FLC.

The rule base characterizes the control The rule base characterizes the control goals and control policy of the domain goals and control policy of the domain experts by means of a set of linguistic experts by means of a set of linguistic control rules.control rules.


The decision-making logicThe decision-making logic

It is the kernel of an FLC. It has the It is the kernel of an FLC. It has the capability of simulating human capability of simulating human decision-making based on fuzzy decision-making based on fuzzy concepts, implication and the rules of concepts, implication and the rules of inference in fuzzy logicinference in fuzzy logic


The defuzzification inferenceThe defuzzification inference

Scale mapping, which converts the Scale mapping, which converts the range of values of output variables range of values of output variables into corresponding universe of into corresponding universe of discourse,discourse,

Defuzzification, which yields a non-Defuzzification, which yields a non-fuzzy control action from an inferred fuzzy control action from an inferred control action.control action.

A defuzzifier converts an inferred A defuzzifier converts an inferred fuzzy control action into a crisp onefuzzy control action into a crisp one


Comparison of Conventional & Comparison of Conventional & Fuzzy DesignFuzzy Design


AdvantagesAdvantages

Reduces Design Development CycleReduces Design Development Cycle Simplifies Design ComplexitiesSimplifies Design Complexities Improve time to marketImprove time to market Better for non Linear systemBetter for non Linear system Improve control performanceImprove control performance Reduces hardware costReduces hardware cost


Greenhouse LayoutGreenhouse Layout


Function of ControllerFunction of Controller


Role of FLC in GHCCRole of FLC in GHCC


Input VariablesInput Variables Difference in temperature between inside greenhouse & Difference in temperature between inside greenhouse &

optimum must be maintained in greenhouse [-10 to +10 ºC]optimum must be maintained in greenhouse [-10 to +10 ºC] Difference in temperature between outside greenhouse & Difference in temperature between outside greenhouse &

optimum must be maintained in greenhouse [-20 to +20 ºC]optimum must be maintained in greenhouse [-20 to +20 ºC] Difference in R-Humidity between inside greenhouse & optimum Difference in R-Humidity between inside greenhouse & optimum

must be maintained in greenhouse [0 to 100 %]must be maintained in greenhouse [0 to 100 %] Difference in R-Humidity between outside greenhouse & Difference in R-Humidity between outside greenhouse &

optimum must be maintained in greenhouse [0 to 100 %]optimum must be maintained in greenhouse [0 to 100 %] Sunlight incident on the greenhouse roof [0 to 20 W/m2]Sunlight incident on the greenhouse roof [0 to 20 W/m2] Seasonal Cloudiness which reduces the sun’s radiation [0 to 100 Seasonal Cloudiness which reduces the sun’s radiation [0 to 100

%]%] Wind speed [0 to 100 mph]Wind speed [0 to 100 mph] Wind direction with respect to the direction of the ventilation Wind direction with respect to the direction of the ventilation

system of the greenhouse system of the greenhouse Measurement error of the sensing system (-4 to 4)Measurement error of the sensing system (-4 to 4) Change in Error of the measurement of the sensing system (-1 Change in Error of the measurement of the sensing system (-1

to 1)to 1)


Output VariablesOutput Variables

Thermal system (0 to 100 %)Thermal system (0 to 100 %) Ventilation & humidification system (0 to Ventilation & humidification system (0 to

100 %)100 %) Thermal shade system (0 to 100 %)Thermal shade system (0 to 100 %) CO2 generation system (0 to 100 %)CO2 generation system (0 to 100 %) Forced ventilation system (0 to 100 %)Forced ventilation system (0 to 100 %) Performance of the system (0 to 100 %)Performance of the system (0 to 100 %)


FLC SystemFLC System


Input Membership FunctionInput Membership Function


Input MFsInput MFs


Output MFsOutput MFs


Rules-1Rules-1


Rules-2Rules-2


Rules-3 & 4Rules-3 & 4


Rules 5 & 6Rules 5 & 6


GUIGUI


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greenhouse climate controller fuzzy logic programing greenhouse climate controller using fuzzy logic...

Documents

fuzzy logic slide

fuzzy concepts

system slide

inferred fuzzy control

non fuzzy control action

decisionmaking logic

fuzzy data manipulation

labels of fuzzy sets