Embedded systems have become integral to various aspects of modern life. They power everything from our smartphones and cars to smart thermostats that regulate our homes. Despite their hidden presence, embedded systems play a crucial role in keeping our technology-driven world running smoothly. However, structured testing is vital to guarantee dependability, performance, safety, and security of these systems. As discussed in our earlier blog on the crucial need for high quality in embedded systems, failure to do so can have a major impact on product success and brand reputation.
To ensure that the right product is developed in the right way, there are processes and methodologies broadly grouped into the V-model verification and validation for embedded products framework. In this article, we delve into V-model verification and validation for embedded products and the process to be covered during each development phase. Independent QA and Testing plays a central role at every stage of this process.
Verification in Embedded Product Development
Verification is essentially the process of checking whether the development done meets the requirements established for the given phase. It encompasses examining business requirements, system requirements, conducting design reviews, and code walkthroughs throughout the product development process.
This type of testing is often referred to as static testing — making sure that the correct product is being created by ensuring it is developed according to defined standards and guidelines. V-model verification and validation for embedded products treats verification as a continuous activity throughout all development phases, not just at the end.
Validation of Embedded Products
Validation is the process of evaluating a system or component during or at the end of the development process to determine whether it meets the defined requirements. It involves checking that the product fulfills its intended purpose in the real-world application and environment.
In embedded product development, validation mostly involves working with the real physical product and checking for functionalities using one or more well-defined testing methodologies. Embedded software quality assurance encompasses both static verification practices and dynamic validation testing.
Independent QA and Testing: Need for V-Model Verification and Validation
Both verification and validation processes are crucial in delivering a high-quality product. Independent QA and Testing provides an objective view of product quality, free from the biases of the development team. V-model verification and validation for embedded products should be conducted in tandem throughout the product development lifecycle. But in today's competitive market, V&V activities often occur in later stages, leading to longer lead times and higher fix costs.
V & V - Cost Impact
When the V-model verification and validation for embedded products process is delayed or not carried out correctly, security and performance issues may be discovered late in the program. Independent QA and Testing ensures such issues are caught at the right stage — when they are cheaper and faster to fix. Conducting verification and validation at relevant stages — Planning, Design, Development, Testing, and Deployment — is crucial to prevent unexpected issues and costly mistakes.
Verification Methodologies
Many standards define verification and validation methodologies based on use cases, such as ASME V&V 40 for medical devices and ISO 26262 for functional safety automotive applications. V-model verification and validation for embedded products follows a systematic approach as illustrated in the diagram below.
V Model In Verification And Validation
The following documentation is needed to evaluate verification under V-model verification and validation for embedded products:
- Business Requirements Documents
- Software/System Requirements Document
- High Level Design Document
- Low Level Design Document
Recommended approaches at each stage of embedded product development:
| Stage | Approach |
|---|---|
| Planning | Requirement review Traceability matrix Integration Plan review |
| Design | Design and Specification analysis Use case review Test plan review Test case review Traceability matrix |
| Development | Schematic review Mechanical design review Code review Traceability matrix |
Being an internal process, it is important to carefully document all activities and results, without missing anything.
Embedded Software Quality Assurance Through Validation
Embedded Software Quality Assurance Consulting Frameworks
Validation is perhaps the most visible part of embedded software quality assurance as it concerns the external stakeholder and serves as proof that the developed product conforms to requirements. Embedded software quality assurance consulting helps organizations establish validation frameworks — choosing the right testing types and tools for each product domain. Validation involves the following testing types:
- Unit Testing
- Integration Testing
- System/Functional Testing
- Acceptance Testing
- Regression Testing
- Performance Testing
- Security Testing
In the V-model verification and validation for embedded products framework, Unit Test Plans (UTPs) are formulated during the module development phase. Unit testing confirms that the smallest independent entity functions accurately when isolated from the rest of the code. Tools: Googletest, JUnit.
Integration Testing:Integration testing validates that independently created and tested groups can effectively coexist and communicate. Integration Test Plans are devised during the Architectural Design Phase. This phase is a critical part of embedded software quality assurance for any multi-module embedded product. Tools: Vector tool, LDRA Suite.
System/Functional Testing:System testing involves testing all components of the system together to verify if the overall product meets specified functional requirements. This occurs when the product is nearly ready to ship, closely mirroring the user's experience. Tools: Embunit, TestBot.
Acceptance Testing:Acceptance testing is carried out by customers or their representatives to determine whether they accept the developed system. It evaluates the product in the actual user environment. Tools: Robot Framework, TestRail.
Regression Testing:Regression testing involves re-running a subset of unit, integration, and system tests after a code change to verify that recent modifications have not negatively affected the product's security, performance, or functionality. Tools: Robot Framework, TestBot.
Performance Testing:Embedded product performance testing evaluates speed, responsiveness, and efficiency under various conditions. It identifies performance bottlenecks and optimizes the system for real-world scenarios.
Embedded System Integration and Testing
Embedded system integration testing validates that all hardware and software subsystems function together as a cohesive product. Embedded system integration is a critical milestone in V-model verification and validation for embedded products — it is where interface mismatches, timing issues, and inter-module communication problems are identified and resolved before system-level validation begins.
Key Differences Between Verification and Validation
| Verification | Validation | |
|---|---|---|
| Purpose | To ensure that the software conforms to its specified requirements and has been developed correctly | To determine whether the software meets the customer's needs and expectations and fulfills its intended purpose in the real-world environment |
| When It Occurs | Followed throughout the development process — activities include code reviews, design inspections, and unit testing | Performed at the end of the development process or during the testing phase — activities include system testing and acceptance testing |
| Focus | Check whether software is built right, according to the specified requirements and design | Check whether the right product has been built, by ensuring it meets the customer's needs and expectations |
| Methods | Uses static techniques such as reviews, inspections, and walkthroughs — does not involve actual execution of code | Uses dynamic techniques such as testing (unit testing, system testing) to evaluate software behavior by executing it |
| Testing Level | May not require a full product for testing | Requires a full product for testing |
Conclusion
In an embedded product development lifecycle, V-model verification and validation for embedded products is essential. Verification ensures the product is built the right way. Validation ensures the right product is built. Together, V-model verification and validation for embedded products helps catch mistakes early, saves cost, and results in stable, reliable products. Independent QA and Testing provides the objective oversight needed to maintain embedded software quality assurance standards throughout the development cycle. Embien's product engineering services team delivers end-to-end Independent QA and Testing support, and our TestBot platform accelerates validation through automated test execution across hardware, firmware, and application layers.