Hi @KAO CHUN YU
The singleton (constant) output membership functions in Fig. 5 indicate that this is a Sugeno fuzzy system; however, you have inadvertently designed a Mamdani fuzzy system. In earlier releases of the Fuzzy Logic Toolbox, the Mamdani FIS is automatically created by default when you open the Fuzzy Logic Designer app. It is necessary to create a new FIS and specify that it is a "Sugeno system."
fis = sugfis('NumInputs', 2, 'NumInputMFs', 5, 'NumOutputs', 1, 'NumOutputMFs', 9)
%% Input MFs
fis.Inputs(1).Range = [-1 1];
fis.Inputs(1).MembershipFunctions(1).Parameters = [-2.0 -1.0 -0.5];
fis.Inputs(1).MembershipFunctions(2).Parameters = [-1.0 -0.5 0.0];
fis.Inputs(1).MembershipFunctions(3).Parameters = [-0.5 0.0 0.5];
fis.Inputs(1).MembershipFunctions(4).Parameters = [ 0.0 0.5 1.0];
fis.Inputs(1).MembershipFunctions(5).Parameters = [ 0.5 1.0 2.0];
fis.Inputs(2).Range = [-1 1];
fis.Inputs(2).MembershipFunctions(1).Parameters = [-2.0 -1.0 -0.5];
fis.Inputs(2).MembershipFunctions(2).Parameters = [-1.0 -0.5 0.0];
fis.Inputs(2).MembershipFunctions(3).Parameters = [-0.5 0.0 0.5];
fis.Inputs(2).MembershipFunctions(4).Parameters = [ 0.0 0.5 1.0];
fis.Inputs(2).MembershipFunctions(5).Parameters = [ 0.5 1.0 2.0];
figure
subplot(211)
plotmf(fis, 'input', 1), grid on
subplot(212)
plotmf(fis, 'input', 2), grid on
%% Output MFs
fis.outputs(1).MembershipFunctions(1).Parameters = -1.00; % NVB
fis.outputs(1).MembershipFunctions(2).Parameters = -0.75; % NB
fis.outputs(1).MembershipFunctions(3).Parameters = -0.50; % NM
fis.outputs(1).MembershipFunctions(4).Parameters = -0.25; % NS
fis.outputs(1).MembershipFunctions(5).Parameters = -0.00; % ZE
fis.outputs(1).MembershipFunctions(6).Parameters = 0.25; % PS
fis.outputs(1).MembershipFunctions(7).Parameters = 0.50; % PM
fis.outputs(1).MembershipFunctions(8).Parameters = 0.75; % PB
fis.outputs(1).MembershipFunctions(9).Parameters = 1.00; % PVB
%% fis.Rules
fis.Rules = [];
rules = [
"input1==mf1 & input2==mf1 => output1=mf1 (1)"
"input1==mf2 & input2==mf1 => output1=mf2 (1)"
"input1==mf3 & input2==mf1 => output1=mf3 (1)"
"input1==mf4 & input2==mf1 => output1=mf4 (1)"
"input1==mf5 & input2==mf1 => output1=mf5 (1)"
"input1==mf1 & input2==mf2 => output1=mf2 (1)"
"input1==mf2 & input2==mf2 => output1=mf3 (1)"
"input1==mf3 & input2==mf2 => output1=mf4 (1)"
"input1==mf4 & input2==mf2 => output1=mf5 (1)"
"input1==mf5 & input2==mf2 => output1=mf6 (1)"
"input1==mf1 & input2==mf3 => output1=mf3 (1)"
"input1==mf2 & input2==mf3 => output1=mf4 (1)"
"input1==mf3 & input2==mf3 => output1=mf5 (1)"
"input1==mf4 & input2==mf3 => output1=mf6 (1)"
"input1==mf5 & input2==mf3 => output1=mf7 (1)"
"input1==mf1 & input2==mf4 => output1=mf4 (1)"
"input1==mf2 & input2==mf4 => output1=mf5 (1)"
"input1==mf3 & input2==mf4 => output1=mf6 (1)"
"input1==mf4 & input2==mf4 => output1=mf7 (1)"
"input1==mf5 & input2==mf4 => output1=mf8 (1)"
"input1==mf1 & input2==mf5 => output1=mf5 (1)"
"input1==mf2 & input2==mf5 => output1=mf6 (1)"
"input1==mf3 & input2==mf5 => output1=mf7 (1)"
"input1==mf4 & input2==mf5 => output1=mf8 (1)"
"input1==mf5 & input2==mf5 => output1=mf9 (1)"
];
fis = addRule(fis, rules);
%% Control Surface
figure
opt = gensurfOptions(NumGridPoints=51);
gensurf(fis, opt), title('Control Surface')
