Examining Today’s Automated Test Equipment

Automated test equipment (ATE) plays a vital role within the aerospace industry. The aerospace industry is incredibly complex and involves interdependent systems such as communication, navigation, command and control systems, but ATE can deliver high-quality, fully featured solutions to fulfill these needs. ATE allows for multiple components and systems to be tested simultaneously, repeatable testing and full documentation as well as saving time. It aids in compliance with federal regulations, standards and safety specifications.

The configurable GPSG-1000 is a portable, easy-to-use GPS and Galileo positional simulator. VIAVI Solutions image.

“ATE allows for tests to be done under various environmental stresses that may be too time-consuming for manual tests,” says Joseph Engler, president of Intepro Systems, Tustin, Calif. “It also allows for ease of collection data versus environmental settings as most systems have recording software to record and store your findings.”

Using a model-based digital twin testing approach and harnessing the power of artificial intelligence (AI), Eggplant Test Software provides extensive coverage, optimizes user experience, speeds up release cycles and improves the quality assurance process. Keysight Technologies image.

The ATC-5000NG is an RF signal generator/receiver for testing Mode A, C and S transponders. VIAVI Solutions image.

MK Test Systems

Hugo Aniksztejn
MK Test Systems

Because functional safety is such a primary concern, ATE methods and processes are a priority in aerospace manufacture and MRO. “Automation of traditional manual measurement and test processes enables standardization of methods and tolerances, automatic judgement of pass, fail, retest requirement, and full traceability of test and measurement results throughout the manufacturing process and the operating lifetime of the aircraft,” says Hugo Aniksztejn, sales manager of MK Test Systems, Somerset, United Kingdom. “With increasing pressure on deliveries, ATE plays a significant role in ensuring quicker testing, data gathering and eliminating human errors. Automated testing not only impacts production in the short term by reducing errors and testing time but also gives OEMs and MROs greater access to valuable data which is then used to drive future changes and improvements.”

VIAVI Solutions

Jeff Coltvet
VIAVI Solutions

According to Jeff Coltvet, senior product manager, VIAVI Solutions, Scottsdale, Ariz., ATEs perform tests that allow for the continued development and maintenance of avionics LRUs (line replaceable unit) in the aerospace industry for:

• MOPS Certification – Using ATC-5000NG and RGS-2000NG

• AIMS Certification– Using IFF-45TS

• Design Verification – Using ATC-5000, RGS-2000NG, IFF-45TS

• Factory – Using ATC-5000, RGS-2000NG, IFF-45TS

• Return to Service – Using ATC-5000, RGS-2000NG, IFF-45TS

Common Types of ATE Test

Darcy Smith
Keysight Technologies

Avionics ATE is usually dedicated to a limited set of test capabilities such as position location, direction finding, or battery test. Darcy Smith, aerospace defense government solutions business lead at Keysight Technologies Inc., Lake Oswego, Ore., explains these instruments tend to be used at the aircraft site so features like size, weight, and battery operation are prioritized over breadth-of-test coverage. “However, the primary test functions needed for testing aircraft electronics can easily be met by more general-purpose test equipment like signal generators, signal analyzers, oscilloscopes, and vector network analyzers which can serve a variety of use cases over the product development life cycle compared to the specialized testers.”

Joseph Engler
Intepro Systems

Intepro Systems specializes in power electronics and battery testing within the aerospace field, and since it focuses on the power side the aircraft, Engler says he is seeing increases in the power distribution on the aircraft and the movement to electric drive on many systems. “The importance of testing these power components exponentially increases the more these parts are part of the critical flight equipment. Intepro’s ATEs are customized to meet these tests. We are integrating higher AC or DC sources and loads to simulate the power distribution for the aircraft systems. Measurement and communications instruments are also included to simulate the real-life environments and monitoring in the aircraft. Our testers include digital multimeter and oscilloscope along with the sources, loads, and communication buses. We then have interface to test the units, typically a Virginia Panel mass pin interface, and then simply program the automatic test using our fill-in-the-screen PowerStar software.”

The large number of circuits involved in an aircraft, transmitting power and signal means that it is impractical to attempt to carry out testing using traditional manual methods. Because of this, ATE is commonly used in testing the electrical characteristics of those circuits, via high-density switching matrices. ATE is connected to the aircraft systems and circuitry via the switching matrices and test signals delivered in the aircraft under software control.

MK Test Systems

Jason Evans
MK Test Systems

“Common tests include continuity resistance, low-voltage isolation, capacitance and high-voltage insulation,” says Jason Evans, managing director at MK Test Systems. “With the increasing number and complexity of databus and communication systems being installed on aircraft, more complex ‘Function’ test ATE is being applied during manufacture and MRO. To deliver testing efficiencies in line with the electrical tests described above, ATE manufacturers are working on developing switching modules that are able to switch these functional signals into the aircraft without degrading the signal.”

Coltvet explains that “if your focus is making improvements to your traffic collision avoidance system (TCAS) LRUs to keep up with market requirements, you want to be able to efficiently run a design and verification test. This is best accomplished using an ATE.” He cites the following components would be common in a design verification ATE design:

• RGS-2000NG TCAS Test Set
• Power supply
• Switching resource
• DMM
• Test control computer
• Required test software
• Databus instrument

Coltvet adds that as an OEM of an avionics transponder production line, one needs to efficiently maintain production rates and that the following components would be common in a final-production test ATE design:

• ATC-5000NG Transponder Test Set
• Power supply
• Switching resource
• DMM
• Test control computer
• Required test software

Advances in ATE

MK Test has recently introduced a Real Time Scanning (RTS) equipment which dramatically reduces the need for interfacing, hookup and testing time. Aniksztejn explains this project initiated as a cooperation with Airbus to reduce testing challenges during production and has proven to have a significant impact as MK Test’s technology is currently in use on all FALs in Toulouse before being installed on other production sites across the globe. “This highlights the push from OEMs to modernize its operation to maximize the output and reduce bottlenecks.”

Engler explains that test departments can lead their companies to a true net zero solution. Bi-directional AC and DC power supplies and regenerative electronic loads reduce the environmental impact of the test department. “The use of bi-directional, regenerative, and four quadrant equipment are huge advancements. While they tend to be more expensive, bi-directional and four quadrant equipment offers greater power densities, reduced heat and potentially reduced equipment in the system that can be either a load or a source. This is especially useful when testing energy storage units.

“Our system’s open hardware architecture means we can take advantage of the latest instruments without impacting the test programs. We can swap an instrument without writing or changing the test program code. A good option for futureproofing our systems.”

“The underlying technologies used in avionics have not evolved quickly,” Smith says. “In fact, many aircraft and avionics systems have been around for decades and must still be maintained. As a result, obsolescence is a big concern for avionics manufacturers. As new instruments are swapped out due to discontinuance, it’s important to take the opportunity to modernize the measurement software. Measurement software that is agnostic to the underlying measuring equipment minimizes the maintenance costs and provides a path to enhanced features required by new avionics solutions. Thus, legacy and new avionics systems can be designed, manufactured, and maintained by this common ATE.”

Addressing the issue of time and tenure with ATEs, Coltvet says due to the longevity of aircraft flying around the world, it is not uncommon for some technologies to be utilized for 20 years or more. He believes this creates a dichotomy where ATEs and instruments must continue to test legacy avionics while being adaptable enough to handle new avionics standards. “VIAVI instruments that go into ATEs are being updated to test to the newer industry standards such as RTCA DO-260C and DO-181F, as well as AIMS 17-1000.

• Additional Squitters (RTCA DO-260C and DO-181F)
• ATC-5000NG, RGS-2000NG
• Phase Overlay (RTCA DO-260C and DO-181F)
• ATC-5000NG, RGS-2000NG
• Mode 5 Level IIB – including ADS-B In (AIMS 17-1000)
• IFF-45TS

“Many of the new ATE instruments have embedded computers running some version of Windows or Linux. This results in not one but several computers in the ATE working together, in an integrated fashion, to accomplish avionics testing.”