Mission profiles are an important part of the product development process and form the basis for the specification of product requirements – but how are mission profiles generated in practice for new products? A new SPM report provides practical examples of mission profiles and their derived tests.

By Susanne Otto

Mission profiling is the process of creating an overview of all the influences that a product is subjected to throughout its life cycle, which typically comprises transport, storage and use environments.

A mission profile takes the following into account: field of application, geographical area, user impact and use profile. A mission profile contains both environmental impacts such as thermal, mechanical, humidity, water, dust, chemical and electromagnetic impact and functional influences related to the pattern of use.

Failure mechanisms and the product’s life cycle

Mission profiles are an important part of the product development process and form the basis of product requirements. Together with acceleration models, mission profiles also form the basis for accelerated life testing and other relevant tests.

Despite this we still lack information about how mission profiles for new products are generated in practice, i.e. how do you find out what is critical for the relevant failure mechanisms, which part of the product’s life cycle and which parameters are relevant and which can be omitted, and how do you transform a mission profile into an actual test? That is why the aim of the ‘Product Mission Profiling’ project has been to give SPM members a tool for developing mission profiles and guidelines to design relevant tests for a given product with input from mission profiles.

The project builds upon the experiences of SPM members, which have been collected via a questionnaire, as well as experience from DELTA (a part of FORCE Technology) . Material from specialist fields of application, such as ZVEI: ‘Handbook for Validation of Automotive Electrical/Electronic Modules’, which is used in the automotive industry, and MIL-STD-810: ‘Environmental Engineering considerations and laboratory tests’, which is used in the military industry, has also been included.

The report provides an introduction to mission profiling or tailoring, as it is known in the military industry, describes the process of developing a mission profile and offers guidelines for using them, as well as analysis and the use of measured field data.

Three cases illustrate the use of mission profiles

The project focuses primarily on mission profiles for the use environment, i.e. mission profiles for other parts of a product’s life cycle (manufacture, storage and transport) are addressed briefly. The process of developing mission profiles is demonstrated by means of three cases.

In the first case, Jørn Gaardsvig from Terma describes those activities that were included in the qualification of a typical Terma antenna system with regard to the mechanical impact which the system experienced, from the final parts of the manufacturing process until end-of-life. The case focuses on defining and describing the impacts, as well as a translation of the calculation input and test parameters.

The next case describes how mission profile analysis can be used to generate data for an accelerated life test of an electric power take-off (E-PTO) for a refuse truck developed and produced by Banke ApS.

In the final case, mission profiling was used both to specify relevant requirements for the development of new types of detectors for measuring emissions from piggeries and also for the qualification of detectors that had already been developed for other applications.

Each case contains:

  • Mission profile for selected relevant stressors such as vibration, humidity, temperature, corrosive gases
  • Anticipated failures and related failure mechanisms, divided into wear-out and overstress failures
  • Proposals for accelerated tests for selected failure mechanisms with special focus on the estimated lifetime.