Automatic Test System (ATS) & Automatic Test Equipment (ATE)
DAU GLOSSARY DEFINITION
The DoD ATS Selection Guide provides amplifying information regarding Automatic Test Systems (ATS) and Automatic Test Equipment (ATE):
ATS - A fully-integrated, computer-controlled suite of electronic test equipment and instrumentation hardware, software, documentation, and ancillary items designed to verify at any level of maintenance the functionality of Unit Under Test (UUT) assemblies. The term UUT includes, but is not limited to, Shop Replaceable Unit (SRUs), Line Replaceable Units (LRUs), Shop Replaceable Assemblies (SRAs), Weapons Replaceable Assemblies (WRAs), circuit cards, aircraft "black boxes," and other removable components from weapons platforms or support systems.
An ATS combines the following three elements:
- ATE - An integrated assembly of stimulus, measurement, and switching components under computer-control that is capable of processing software routines designed specifically to test a particular UUT or group of UUTs. ATE software includes operating system software, test executive software, and instrument control software.
- Test Program Set (TPS) - ATE interface hardware and other ancillary equipment that connects the UUT to the ATE, plus test program software specific to the UUT with required documentation. The TPS software directs all test functions including fault isolation and diagnostics, and can certify the condition of a UUT. Ancillary hardware consists of cables, probes, holding fixtures and peculiar instrumentation.
- Test Environment - The test environment includes a description of the ATS architecture, programming and test specification languages, compiler, development tools and provisions for capturing and using UUT design requirements and test strategy information in the generation and maintenance of TPS software.
ATE is typically very flexible in its ability to test different kinds of electronics. It can be configured to test LRUs, WRAs, and circuit cards (SRUs or SRAs). ATE is also used to test All-Up-Round (AUR) weapons and weapon sections. Since each UUT likely has different connections and input/output (I/O) ports, interfacing the UUT to the ATE normally requires an interconnecting device known as an Interface Device (ID) which physically connects the UUT to the ATE and routes signals from the various Input/Output (I/O) pins in the ATE to the appropriate I/O pins in the UUT.
An objective of the ATE designer is to maximize the capability inherent in the ATE itself so that IDs remain passive and serve to only route signals to/from the UUT. However, since it is impossible to design ATE which can cover 100% of the range of test requirements, IDs sometimes contain active components which condition signals as they travel to and from the ATE. The more capable the ATE, the less complex the IDs must be. ATE with only scant general capability leads to large, complex and expensive IDs. Some IDs contain complex equipment such as pneumatic and motion sources, optical collimators, and heating and cooling equipment.
DoDI 5000.91, Product Support Management for the Adaptive Acquisition Framework, states: “The Program Manager (PM), through the Product Support Manager (PSM), will minimize unique Test Measurement and Diagnostic Equipment (TMDE), tools, and support equipment by using Military Department- or DoD-approved families of TMDE, tools, and support equipment in DoD field and depot operations to the maximum extent possible.“ This policy applies to ATS and ATE. The DoD ATS Executive Directorate amplifies this with the following: “ATS policy is to minimize the life cycle cost of providing automatic test systems for weapon systems support at DoD field, depot, and manufacturing operations, and to promote joint service automatic test systems interoperability, Program Managers shall use approved DoD ATS Families as the preferred choice to satisfy automatic testing support requirements. Commercial-off-the-Shelf (COTS) solutions that comply with the DoD ATS Technical Architecture should only be used if the Milestone Decision Authority concurs that an approved DoD ATS Family will not satisfy the requirement. Automatic Test System selection shall be based on a cost and benefit analysis over the system life cycle.”
An ATS Family consists of ATSs that are interoperable and have the capability to support a variety of weapon system test requirements through common and flexible hardware and software architectures that permit addition or expansion of testing capability with minimal impact to the ATS logistics support profile, system software and Test Program Sets (TPS). ATS Families are formally designated as such by OSD. The identified DoD ATS Families include:
- Consolidated Automated Support System (CASS) Family of Testers (FoT)
- Integrated Family of Test Equipment (IFTE)
- Marine Corps Automatic Test System (MCATES)
- Joint Service Electronic Combat Systems Tester (JSECST)
- Versatile Depot Automatic Test System (VDATS)
In addition to directing use of DoD common or standard ATS/ATE, it is a best practice to include a Test Requirements Document (TRD) (Data Item Description DI-ATTS-80041A) as a contract deliverable during the Engineering & Manufacturing Development (EMD) (or equivalent phase in other Adaptive Acquisition Framework pathways). Delivery of a TRD facilitates development of a TPS software product (e.g., for standard ATS/ATE), by an organic Software Support Activity or competed contract, depending on the business case and other relevant factors. (Note: DI-ATTS-80041A, para 10.2.4 Part D refers to the outdated ATLAS language and the CDRL should be tailored to reflect a more modern standard such as ATML (IEEE 1671.1 and 1671.3) for UUT(s).)
The intent of an open systems approach is to define an acquisition environment that makes DoD the smartest, most responsive buyer of the best goods or services that meet our warfighters' needs at the best dollar value over the life of the product. A major theme is to define ways to use commercial products on the market and preserve our legacy investments in Test Program Sets. For ATSs this means:
- Leveraging non-recurring investments already made in ATS Families across multiple applications
- Evolving the capabilities of these Families of ATS by migrating their content towards industry-wide standards
- Facilitating intra- and inter-service level interoperability by encouraging common and interoperable support solutions
- Encouraging the use of commercial items that meet defined ATS capabilities within ATS Families and as ATS alternatives by promulgating an open architecture based on commercial standards
- Maintaining legacy TPSs
The ATS Selection Process is used when an ATS is required, whether it is during the development or upgrade of a weapon system, replacement due to ATS obsolescence, or modification of an ATS. The process shown below provides a structured approach to ATS selection. This process consists of four primary steps:
- Definition of weapon system support/test requirements
- Definition of ATS alternatives
- Cost & benefit analysis of alternatives
- Alternative selection