Never has the need for test been greater. As the pace of innovation and
customer expectations have increased, so has the pressure to get
differentiated new products to market quickly. Ian Bell reports
The economic downturn of the past three years has not reduced the need to
innovate, but it has added the restraint of fewer resources. Not only
does the successful manufacturer have to test more functionality, on a
higher volume of units, in a shorter space of time, but it also needs to
build test systems faster, operate them with fewer staff and take up less
space on the manufacturing floor. All these conditions drive new
requirements for validation, verification and manufacturing test. A test
platform must include rapid test development tools adaptable enough to be
used throughout the product development flow. The need to get products to
volume quickly and manufacture them efficiently requires high-throughput
test. And as you incorporate new innovations to differentiate your
products, your test system must quickly adapt to test the new features.
Virtual instrumentation (VI) uses mainstream computer technologies
combined with flexible software and modular hardware to create powerful,
computer-based test solutions that meet specific needs. VI incorporates
the following three essential technologies for test: intuitive software
tools for rapid test development; fast, precise, modular I/O, and a
PC-based platform with integrated synchronisation
As automation has increasingly become a requirement to test complex
products rapidly; software has become an essential element in all test
systems -- from design verification through to highly automated
manufacturing test. Delivering systems that can adapt to testing new
functionality requires an integrated set of test development tools. These
tools include test management, test development and I/O drivers.
The second essential technology for test is modular I/O, including
technologies such as modular instrumentation and data acquisition.
Modular I/O uses commercial chip technologies to create virtual
instruments with high performance and low cost. The rapid development of
widely used commercial technologies like analogue-to-digital converters,
digital-to-analogue converters, FPGAs and DSPs has resulted in the rapid
growth of modular I/O functionality and performance. In many cases, the
accuracy of virtual instrumentation exceeds that of traditional
instruments.
The PC is becoming the essential integrating platform at the centre of
the test system and not just peripheral to it. The gigahertz processors,
high-speed buses, wide availability of software, constantly increasing
performance and extremely low price make the PC an ideal test platform.
As an example, consider the performance advances the PC has undergone in
the past 20 years. The only other element of test systems that has
undergone a performance increase of this magnitude is perhaps the device
under test itself!
By combining powerful, flexible software with modular instrumentation
hardware, engineers and scientists can create customised instruments that
meet their application needs. The proprietary, fixed functionality
inherent with traditional instruments is no longer a limiting factor in
providing robust test solutions. Using VI, test engineers can define the
exact characteristics for their automated acquisition, analysis and
reporting, without worrying about the incompatibilities that may exist
among different pieces of hardware and software from different vendors.
This significant productivity gain is possible because of tight coupling
between the software and hardware. Whether engineers and scientists are
acquiring a single channel over a short period of time or thousands of
channels over many days, VI employs the same platform of hardware and
software to accomplish both tasks.
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