quad = mbcquadratic(train, 'Response', 'NOx', 'Predictors', 'Speed','Load','Timing'); quad = fit(quad); summary(quad); % See coefficients Use the calset object to optimize lookup tables for multiple responses (e.g., minimize BSFC, keep NOx < limit).
% 3. Build knock model (binary: 0=no knock, 1=knock) knock_model = mbcgp(data, 'Knock', 'Speed','Load','Timing', 'Distribution','binomial'); knock_model = fit(knock_model);
% Create a 2D lookup table lut = mbc2dlookup('filename.slx', table); writeblock(lut); Or generate C-array: mcc toolbox
writecfile(table, 'calibration_table.c'); | Object/Function | Purpose | |----------------|---------| | xydesign | Generate DOE points | | mbcdata | Manage experimental data | | mbcgp , mbcquadratic | Build models | | calset | Multi-objective optimization | | mbc2dlookup | Export to Simulink | | crossvalidate | Validate model accuracy | 4. Practical Example: Engine Calibration Goal: Calibrate spark timing for max torque while limiting knock.
gp = mbcgp(train, 'Response', 'Torque', 'Predictors', 'Speed','Load'); gp = fit(gp); plot(gp); % Check fit : (best for non-linear): % 1
data = mbcdata.import('engine_test.csv'); % Remove outliers data = removeoutliers(data, 'Response', 'BSFC'); % Split into training/validation [train, val] = splitdata(data, 0.8); Use mbcmodels to create response surface models.
% Example: Create a space-filling design factors = 'Speed', 'Load', 'Timing'; range = [800 6000; % RPM 20 120; % Load (%) -10 30]; % Timing (deg) des = xydesign(factors, range, 'NumPoints', 50); scatter(des); % Visualize Load measured data from engine tests. Optimize timing cal = calset(torque_model
(best for non-linear):
% 1. Load data load engine_data.mat % contains Speed, Load, Timing, Torque, Knock % 2. Build torque model torque_model = mbcgp(data, 'Torque', 'Speed','Load','Timing'); torque_model = fit(torque_model);
% Define calibration set cal = calset(gp_model, 'Goal', 'minimize', 'Response', 'BSFC'); % Add constraint cal = addconstraint(cal, 'NOx <= 0.5'); % Define breakpoints for lookup table breaks = [800,2000,4000,6000], [20,40,60,80,100]; cal = optimize(cal, breaks); % Retrieve optimized table table = gettable(cal); Generate a Simulink lookup table block:
% 4. Optimize timing cal = calset(torque_model, 'Goal','maximize', 'Response','Torque'); cal = addconstraint(cal, 'pred(knock_model) <= 0.1'); % knock probability <10% cal = setfactorrange(cal, 'Timing', -10, 30); optimal = optimize(cal);