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Hi ehab,

thank you for your post and your kind words.

From what I was able to quickly see in QtFuzzyLite was that your InputVariable in4 needs a value higher than ~50 in order activate any rule. From all your rules, each has and in4 is ..., hence when in4 is nothing, you will get no active rules. In the case no rules are activated, your output variable produces NaN because it is its default value. Please,

– Change the default value to whatever you expect when no rules are active.

– Set the Accumulation operator in your output variable to none to achieve the regular operation (see documentation here).

– For better performance, you explicitly set WeightedAverage to work on TakagiSugeno.

– Check QtFuzzyLite as it will let you find issues with your controller very easy and very quick QtFuzzyLite with many terms and rules

In summary, the following changes should be made:

OutputVariable: out1
enabled: true
range: 67.000 425.000
accumulation: none
defuzzifier: WeightedAverage TakagiSugeno
default: 0.0 #if this is what you expect