Model Advisor & Custom Checks - Model-Based Development

Built-In Model Advisor Check Categories

Category	Check Examples	When to Run
By Product > Embedded Coder	Code gen readiness, storage class errors, optimisation opportunities	Before every code generation
By Industry Standard > MAAB	All 100+ MAAB 3.0 guidelines; signal naming, block usage, Stateflow rules	Every model commit (CI)
By Industry Standard > DO-178C/ISO-26262	Safety-relevant modelling patterns; MC/DC readiness	At each phase gate
By Product > Simulink Design Verifier	Property proving readiness; test generation prerequisites	Before SLDV run
Custom checks	Company/project-specific rules (signal prefix policy, forbidden blocks)	Every commit (CI)

Writing a Custom Model Advisor Check

MATLABcustom_ma_check.m

% Custom Model Advisor check:
% Rule: all Constant blocks must use "single" data type (no double)
% This prevents accidental double-precision constants in generated code

function defineModelAdvisorChecks()
    rec = ModelAdvisor.Check("com.mycompany.check.constant_type");
    rec.Title = "Constant blocks must use single data type";
    rec.TitleTips = "Double-precision constants generate 64-bit code on ECU";
    rec.setCallbackFcn(@checkConstantTypes, "None", "StyleTwo");
    rec.setInputParametersLayoutGrid([1 1]);

    mdladvRoot = ModelAdvisor.Root;
    mdladvRoot.register(rec);
end

function [result, msg] = checkConstantTypes(system)
    % Find all Constant blocks
    blocks = find_system(system, "BlockType", "Constant");
    bad_blocks = {};

    for i = 1:numel(blocks)
        dtype = get_param(blocks{i}, "OutDataTypeStr");
        if strcmp(dtype, "double") || strcmp(dtype, "Inherit: Inherit via back propagation")
            bad_blocks{end+1} = blocks{i}; %#ok
        end
    end

    if isempty(bad_blocks)
        result = ModelAdvisor.ResultDetail;
        result.IsInformationOnly = true;
        msg = "All Constant blocks use explicit non-double types.";
    else
        result = ModelAdvisor.ResultDetail;
        result.IsInformationOnly = false;
        for i = 1:numel(bad_blocks)
            result.recordAction(bad_blocks{i}, "warning", ...
                "Constant block uses double or inherited type", ...
                "Change Output data type to single or int16");
        end
        msg = sprintf("%d Constant block(s) use incorrect data type", numel(bad_blocks));
    end
end

Summary

Custom Model Advisor checks codify project-specific modelling rules that go beyond the standard MAAB guidelines. Examples: enforce a signal naming convention specific to your project, verify all Constant blocks use explicit non-double types, check that all subsystems have a non-empty Description field (required for ASPICE SWE.3 documentation). Once written, custom checks integrate seamlessly into the standard Model Advisor workflow and CI pipeline - engineers see them alongside MAAB checks and get the same pass/fail/fix report. The investment in writing custom checks pays off immediately: a rule that is checked automatically cannot be forgotten, and the same check runs on every model in the project without additional effort.

🔬 Deep Dive — Core Concepts Expanded

This section builds on the foundational concepts covered above with additional technical depth, edge cases, and configuration nuances that separate competent engineers from experts. When working on production ECU projects, the details covered here are the ones most commonly responsible for integration delays and late-phase defects.

Key principles to reinforce:

Configuration over coding: In AUTOSAR and automotive middleware environments, correctness is largely determined by ARXML configuration, not application code. A correctly implemented algorithm can produce wrong results due to a single misconfigured parameter.
Traceability as a first-class concern: Every configuration decision should be traceable to a requirement, safety goal, or architecture decision. Undocumented configuration choices are a common source of regression defects when ECUs are updated.
Cross-module dependencies: In tightly integrated automotive software stacks, changing one module's configuration often requires corresponding updates in dependent modules. Always perform a dependency impact analysis before submitting configuration changes.

🏭 How This Topic Appears in Production Projects

Project integration phase: The concepts covered in this lesson are most commonly encountered during ECU integration testing — when multiple software components from different teams are combined for the first time. Issues that were invisible in unit tests frequently surface at this stage.
Supplier/OEM interface: This is a topic that frequently appears in technical discussions between Tier-1 ECU suppliers and OEM system integrators. Engineers who can speak fluently about these details earn credibility and are often brought into critical design review meetings.
Automotive tool ecosystem: Vector CANoe/CANalyzer, dSPACE tools, and ETAS INCA are the standard tools used to validate and measure the correct behaviour of the systems described in this lesson. Familiarity with these tools alongside the conceptual knowledge dramatically accelerates debugging in real projects.

⚠️ Common Mistakes and How to Avoid Them

Assuming default configuration is correct: Automotive software tools ship with default configurations that are designed to compile and link, not to meet project-specific requirements. Every configuration parameter needs to be consciously set. 'It compiled' is not the same as 'it is correctly configured'.
Skipping documentation of configuration rationale: In a 3-year ECU project with team turnover, undocumented configuration choices become tribal knowledge that disappears when engineers leave. Document why a parameter is set to a specific value, not just what it is set to.
Testing only the happy path: Automotive ECUs must behave correctly under fault conditions, voltage variations, and communication errors. Always test the error handling paths as rigorously as the nominal operation. Many production escapes originate in untested error branches.
Version mismatches between teams: In a multi-team project, the BSW team, SWC team, and system integration team may use different versions of the same ARXML file. Version management of all ARXML files in a shared repository is mandatory, not optional.

📊 Industry Note

Engineers who master both the theoretical concepts and the practical toolchain skills covered in this course are among the most sought-after professionals in the automotive software industry. The combination of AUTOSAR standards knowledge, safety engineering understanding, and hands-on configuration experience commands premium salaries at OEMs and Tier-1 suppliers globally.