Design Validation (DV Test)

Design validation (DV) is a testing process that aims to ensure if the design of a product or system is really working in life, and parallel fulfils the customer needs by meeting the specified requirements (not only on paper!).

So basically design validation means physical testing activities and must be performed on prototypes or concepts. DV is applied in all major industries, and it is highly mandatory in safety relevant sectors (e.g. automotive, aerospace, etc.).

Design validation is also referred to as design and development validation, for example in ISO 9001. Note: validation is not equal to verification, as verification means the evaluation whether the product or system has been designed and produced according to the specifications, drawings, regulations, instructions, etc.

Simply said:

• Verification: did I make what I had written down previously?
• Validation: did I make what really works (and what the customer needs)?

During the conduction of design validation tests, the engineers intend to measure the performance of the product, evaluate its function and simulate the environment of the typical use. The below list contains usual test methods of the automotive industry for mechanical, electrical components, or both:

• Functional and performance testing (e.g. vehicle road test, active test of electrical assemblies).
• Mechanical tests (e.g. surface hardness test, mechanical shock, vibration test, drop test, test for strength and robustness, etc.).
• Electrical tests and EMC (electromagnetic compatibility) tests.
• Chemical exposure and material tests (e.g. for corrosion).
• Environmental and climate tests (e.g. ADT – Accelerated Durability Testing, ART – Accelerated Reliability Testing, heat-shock, vehicle test, special life-time testing, Xenon-arc Accelerated Exposure, etc.).

A complete and successful test proves, that the design itself is reliable.

Partial example of Design validation of an electric module in the automotive industry:

Design validation is a key part of the automotive APQP framework’s “Product and Process Validation” phase. In APQP, the “Production validation testing” is and engineering test, which validates if the product meets engineering standards and specifications. That means DV test must be performed, finished and evaluated before product launch. On top of that, engineers in the automotive or aerospace industry, start design validation tests already on the first prototypes (e.g. A, B samples), before the design freeze. This is very important on those products, that are considered as high-tech, or using totally new technologies.

Not only the APQP manual, but also ISO/TS 16949 and IATF 16949 request DV test to be finished prior to the delivery, and the analysis of field reports for previously designed, similar products. Maintaining test documents and records is also mandatory.

Suggestions

It is very important to note that design validation is not equal to design verification. Both are mandatory elements in quality and project management; however, the intention is different.

• Validation: a physical test of the product that validates, if the design of the product / system itself is capable of meeting design requirements.
• Verification: an exercise on paper that checks if the design is developed according to, and complies with standards, governmental regulations, industry-specific regulations, customer requirements. In addition, it analyses if the design outputs met the design input requirements.

Conclusion

• Design validation is a testing process that aims to ensure if the design of a product or system meets the specified requirements, and thus all the customer needs.
• DV is also referred to as design and development validation, for example in ISO 9001.
• Design Validation is not equal to Design Verification.
• DV is a very important element of design and development, as it proves the capability of the design itself.
• DV has to be finished (with successful result) before the serial launch of the relevant product.