Requirement Traceability in Simulink: How to Use It Effectively

In Simulink, requirement traceability is done by linking Requirement objects to model elements using the Requirements Toolbox. You create requirements, link them to blocks or subsystems, and then use traceability reports to verify coverage and compliance.

Syntax

Requirement traceability in Simulink involves these main steps:

• req = reqmgr.create('RequirementName'): Create a requirement object.
• link = reqmgr.link(req, modelElement): Link the requirement to a model element like a block or subsystem.
• report = reqmgr.generateTraceabilityReport(): Generate a report showing linked requirements and coverage.

Here, reqmgr is the Requirements Manager interface in Simulink.

matlab

reqmgr = slreq.requirements.Manager.getInstance();
req = reqmgr.create('SpeedControlReq');
modelElement = 'myModel/SpeedController';
link = reqmgr.link(req, modelElement);
report = reqmgr.generateTraceabilityReport();

Example

This example shows how to create a requirement, link it to a Simulink block, and generate a traceability report.

matlab

reqmgr = slreq.requirements.Manager.getInstance();

% Create a new requirement
req = reqmgr.create('MaxSpeedLimit');
req.Text = 'The system shall not exceed 120 km/h.';

% Specify the model and block to link
modelName = 'speedControlModel';
load_system(modelName);
blockPath = [modelName '/SpeedLimiter'];

% Link the requirement to the block
link = reqmgr.link(req, blockPath);

% Generate and open the traceability report
report = reqmgr.generateTraceabilityReport();
open(report);

Output

A traceability report window opens showing the 'MaxSpeedLimit' requirement linked to the 'SpeedLimiter' block in the 'speedControlModel'.

Common Pitfalls

• Not loading the Simulink model before linking requirements causes errors.
• Linking requirements to incorrect or non-existent model elements leads to broken traceability.
• Forgetting to save the model or requirements manager state can lose links.
• Using inconsistent naming for requirements makes tracking difficult.

Always verify the model is open and the block path is correct before linking.

matlab

reqmgr = slreq.requirements.Manager.getInstance();
req = reqmgr.create('SafetyReq');

% Wrong: Model not loaded
% link = reqmgr.link(req, 'myModel/NonExistentBlock'); % Causes error

% Correct:
load_system('myModel');
link = reqmgr.link(req, 'myModel/ExistingBlock');

Quick Reference

Action	Command/Method	Description
Create Requirement	reqmgr.create('ReqName')	Creates a new requirement object
Set Requirement Text	req.Text = 'Description'	Defines the requirement details
Link Requirement	reqmgr.link(req, 'Model/Block')	Links requirement to model element
Generate Report	reqmgr.generateTraceabilityReport()	Creates traceability report
Open Model	load_system('ModelName')	Loads Simulink model before linking

Key Takeaways

Use the Requirements Manager in Simulink to create and manage requirements.

Always load your Simulink model before linking requirements to blocks or subsystems.

Link requirements directly to model elements for clear traceability.

Generate traceability reports to verify requirement coverage and compliance.

Avoid broken links by verifying model element paths and saving your work.