As manufacturers struggle to reduce their product development cycles in order to stay competitive, test automation is seen as the best strategy to save time and improve product reliability, which ultimately results in cost savings. This article looks at the latest trends and solutions in T&M automation
Rapid advancements in semiconductor technology giving us smaller chips with even more performance, are driving the implementation of cutting-edge functionality in electronic gadgets. Today, mobile phones are not just simple telephones but mobile entertainment systems providing embedded features like LTE, 1020p video playback, GPS, GLONASS, WiFi, Bluetooth, wireless charging and digital camera.
“Test automation is required to cope with a large number of complex measurements in production houses and test labs within a reasonable amount of time and, in addition, allow overnight or weekend regressions. Scripts are coded with series of commands to control instruments remotely and run a measurement routine without human interaction,” says Nidhi Sharma, assistant manager-product support & applications, Rohde & Schwarz India.
In this cut-throat electronics market where drastically reduced product development cycles are still expected to bring out reliable devices, the primary drivers to a successful product are speed of test and quality control.
Stephen Hire, GM, Aeroflex Asia, explains trends in consumer, business and defence markets that are driving the ever greater need for complexity: “First, there is product and component complexity. Many of the calibration and verification stages in modern electronic equipment can only be performed through a tight interaction of test equipment, software adjustment and device control, which more or less mandates automated processes.”
“Secondly, a latest smartphone contains few items that can be easily replaced or repaired in an authorised service centre. So to avoid high costs of returning units to the factory, maximising the quality level through rigid process control is crucial for managing total costs,” he adds.
In defence electronics, pressure is even greater on test engineers. Thankfully, systems such as microwave test systems are available that can be used to make tens of thousands of measurements on mission-critical radar systems over multiple frequency points at a very high speed. So defence forces can be certain that there are no gaps in performance. Automation also enables end products to go through the same rigorous testing in the maintenance stage, ensuring that these high-cost systems do not degrade over time.
Testing during design
A study conducted by researchers at NASA Johnson Space Center stated that finding a product defect during production was 21 to 78 times more expensive than finding it during design. Increasing the test coverage during design can bring about a dramatic reduction in relative cost to repair defects.
Satish Mohanram, technical marketing manager, National Instruments India, says, “The only way to get better at this is to be able to automate the test and have a reconfigurable test system in which multiple test cases can be deployed. Test and measurement has started to move earlier in the product development cycle, and with software defining most of the product’s functionality, embedded software validation is also becoming an important focus area. This is made possible with a new approach called ‘in-loop testing.’”
From the user perspective, the earlier manual testing methodology had error and cost drawbacks. Since the system was manual, the arrangement always presented gauge repeatability and reproducibility (GRR) errors in the system. In addition, operator costs were directionally proportional to T&M complexities.
“Nowadays, T&M automation solutions have evolved to reasonably low-cost, semi-automatic and fully automatic solutions. Users are seeing this as a boon for their T&M requirements. These tools not only save manpower costs incurred by users but also help in ensuring 100 per cent accuracy with increased throughput,” explains T. Anand, managing director, Knewron.
General-purpose operating systems like Windows and Linux, coupled with affordable, easily available performance hardware, have increased the flexibility of off-the-shelf instruments, leading to customised and application-oriented solutions.
“Providing test application solutions customised or otherwise is one domain where product companies look to leverage and extend their technical expertise to provide more than just the products to their end users. The term ‘solution’ is not well defined, since the application requirement of one customer may be different from another. Solution would normally mean taking necessary steps to get the customer to where he intended to be in the first place when he decided to procure your test instruments. This will, at times, require development of a tailormade application where engineers from the product company need to work closely with engineers from the end user company,” explains Navjodh Dhillon, application engineer, Agilent Technologies.
Nowadays, T&M automation solutions have evolved to reasonably low-cost, semi-automatic and fully automatic solutions. Users are seeing this as a boon for their T&M requirements. These tools not only save manpower costs incurred by users but also help in ensuring 100 per cent accuracy with increased throughput”
— T. Anand, managing director, Knewron
Many of the calibration and verification stages in latest electronic equipment can only be performed through a tight interaction of test equipment, software adjustment and device control, which more or less mandates automated processes”
— K. Stephen Hire, GM, Aeroflex Asia
1. Real-time monitoring capabilities
2. Faster response capabilities
5. Reliability – repeatability & reproducibility (R&R)
These features not only help design firms in differentiating their products and solutions but also provide larger support in future applications, scale-ups and servicing. They substantially improve automation quality and reduce costs.
—T. Anand, managing director, Knewron
Mohanram adds, “Most standalone instruments cannot change their functionality as fast as changes in the device under test (DUT) due to the fixed user interface and firmware that must be developed and embedded in the instrument. Thus test engineers are turning to a software-defined approach to instrumentation so that they can quickly customise their equipment to specific application needs and integrate testing directly into the design process. Not only does this approach provide flexibility, it also gives test engineers the ability to take advantage of the performance provided by the latest PC, CPU and bus technologies.”
The new trend of utilising tools based on .NET framework, ActiveX and Java has allowed developers to target all common operating systems like Windows, Linux and more, enabling rapid application development by leveraging the huge amount of existing knowledge already available.
“This has enabled development of well-tested, stable and reliable applications built on proven frameworks. Apart from the available graphical programming environments, languages like C# and .NET provide just the right balance between flexibility and ease of use. Programming with text-based languages is not difficult anymore with most IDEs supporting automatic skeleton code generation, cutting down development time and effort and enabling rapid creation of applications for customisation and test automation. Test developers can take advantage of powerful hardware, including multicore processors in general-purpose computers, to take application performance to unprecedented levels,” adds Dhillon.
Test engineers are turning to a software-defined approach to instrumentation so that they can quickly customise their equipment to specific application needs and integrate testing directly into the design process. Not only does this approach provide flexibility, it also gives test engineers the ability to take advantage of the performance provided by the latest PC, CPU and bus technologies”
— Satish Mohanram, technical marketing manager, National Instruments – India
Standards bring order to chaos
Industry standards have brought a new level of consistency in software and hardware design, and taken uncertainty out of reusing application libraries and changing vendor-specific hardware.
Dhillon explains, “The end user can now focus on the requirement rather than being limited by a single vendor’s hardware. He can mix and match between hardware from various vendors to choose the hardware that exactly fits his requirement and yet be able to integrate them in one test system with a single application controlling and automating the entire setup. This is quite different from the situation about two decades ago when there was no unifying platform and vendors struggled to get a newer variant of their own hardware to work with their software framework. Of course, inter-vendor operability was a far cry at that time.”
PXI seems to be the uniting standard for most T&M equipment.
Hire explains: “The PXI standard moves automation forward in a number of ways. First, with a separate PC controller and high-speed Ethernet, test speed improves. The ability to upgrade the PC processor to take advantage of faster models also delivers valuable and cost-effective improvements. In comparison, traditional test equipment were stuck with the original processor with which these were designed and an upgrade usually meant replacing the entire instrument. When a factory is producing several million products a month, even a 2-3-second speed gain from improved processing power makes a large cumulative difference.”
“Second, PXI separates the test hardware from software drivers. The benefit of this is that the same modules can be used for a variety of different applications. Manufacturers can run different programs on the same hardware and still have the advantage of optimising the test performance for the specific end product. As products change, new software can be developed in parallel—or if a production line needs to make several different variants of the product, multiple software applications can be used to quickly reconfigure a line to meet changing customer needs,” he adds.
Test and measurement is much more aligned with mainstream technology than ever before. We can be sure that it will go hand in hand with the newest technologies and even play a part in defining them. Maybe we can expect voice-input-controlled instruments and 3D signal visualisation tools in the time to come”
— Navjodh Dhillon, Application Engineer, Agilent Technologies
These benefits have enabled a huge number of equipment compatible with PXI platform. “Being an open PC-based platform, PXI offers a wide variety of real-time processor options including several high-performance multi-core processors. With more than 1200 products from more than 70 vendors, it is the platform of choice for thousands of companies worldwide,” adds Mohanram.
Coming up next…
Test automation has progressed by leaps and bounds over the years, giving users the option to choose from wireless portable and real-time automation solutions. Networking capabilities offered by T&M solutions are another factor helping in easier reporting. So where is test and measurement headed now?
“Test and measurement is much more aligned with mainstream technology than ever before. We can be sure that it will go hand in hand with the newest technologies and even play a part in defining them. Maybe we can expect voice-input-controlled instruments and 3D signal visualisation tools in the time to come,” answers Dhillon.