COTS to the rescue: Saving time and money by buying off the shelf
With so many designs running late, never releasing to market, or failing after release, something needs to be done to get more high-quality products out more quickly. One way to address both of these issues is to prototype the systems better by integrating real-world signals and real hardware into the design process earlier. This way, high-quality designs can be iterated on and problems would be found (and fixed) earlier.

Today, if you are creating custom hardware for final deployment, it is difficult to develop the software and hardware in parallel because the software is never tested on representative hardware until the process reaches the system integration step.

This is a problem because waiting until the system integration to test the design with real I/O and real signals may mean that you discover problems too late to meet design deadlines. Using flexible COTS prototyping platforms can streamline this process and eliminate much of the work required for hardware verification and board design. With graphical system design, engineers can take the specific components they need for their systems and use software to easily integrate and program the overall system.

For most systems, a prototyping platform must incorporate the same components of the final deployed system. These components include a real-time processor for executing algorithms deterministically, programmable digital logic for high-speed processing or interfacing the real-time processor to other components, and a variety of I/O types and peripherals (see Figure 3). Finally, as with any system, if the off-the-shelf I/O does not serve all of your needs, the platform should also be extensible and customizable when needed.

National Instruments offers several types of prototyping platforms, including NI CompactRIO, which contains all of the basic building blocks of an embedded system. The controller features a 32-bit processor running a real-time operating system. The CompactRIO backplane includes an FPGA that can implement high-speed processing and also configures and provides interfaces to the I/O modules.

These I/O modules feature options for analog input and output, digital input and output, and counter/timer functionality. Each of the modules includes direct connectivity to sensors and actuators as well as built-in signal conditioning and isolation. A module development kit is also available so developers can expand the platform to include custom modules – all plugging into this COTS framework.

Additionally, CompactRIO is industrially packaged (-40 to 70 °C, 50 g shock) with a small footprint (3.5 by 3.5 by 7.1 in.) and low power requirements (7 to 10 W typical), making it ideal for not only prototyping but also the deployment of in-vehicle, machine control, and onboard predictive maintenance applications.

Daewoo Electronics recently used CompactRIO and LabVIEW to decrease its time to prototyping for next-generation holographic digital data storage (HDDS) device by nearly 10 times to a month. The alternative for Daewoo was a DSP board, however, while this was available off the shelf, if did not have to breadth of packaged I/O or the ease of software design that Daewoo required. Using CompactRIO, the company implemented a completely functional electro-optical motion control system that controlled three independent motors. This motion-control system interfaced to an external 8M gate Xilinx FPGA that conducted video decoding.

Final system deployment
Once prototyping is complete, graphical system design platforms must allow deployment of your code to a final, custom device. LabVIEW provides the capabilities to target code to any 32-bit processor. Using the same platform to target custom devices provides a much easier and efficient transition from prototype to deployment.

A graphical approach can provide many key advantages including a consistent interface for I/O components, inherent parallelism, and opportunities to optimize underlying C code.  I/O nodes such as those shown in Figure 4  provide simple interfaces to basic I/O components for analog and digital I/O.  Additionally, these I/O nodes provide interfaces to specific device drivers to read and write to peripherals such as serial or Ethernet interfaces. Finally engineers need the ability to tweak generated C code to optimize and tune the embedded performance of the device.  Graphical paradigms can accomplish this by allowing C code to be written within the graphical context.

The abstractions found in a higher-level graphical language improve the overall efficiency of the design process by assuming the burden of proper execution.  This is insured by porting the graphical paradigm to a third-party C cross compiler to properly link, compile, and download the code to the custom processor.

This new technology empowers a broader range of engineers, scientists, and domain experts to design algorithms, develop applications, program logic, prototype system and deploy those systems to their targets of choice.

Conclusion
Using a single graphical programming platform for algorithm design to prototyping to deployment can be a very efficient way to implement new and innovative functionality to your devices. Whether designing a digital filter, an ECU or a machine control system, the idea behind graphical system design is porting highly optimized designs to flexible COTS hardware and then to custom hardware as needed.  Embedding intelligence and signal process is becoming essential to differentiate hardware products, especially in embedded and distributed applications.  Thus, it is no surprise that software is playing a major role for these systems either.

Using a single platform reduces overall startup time, especially on subsequent designs.  It also allows engineers the flexibility of reprogrammable processors and custom I/O modules.

About the author: Ranjit Nambiar is Area Sales Manager, National Instruments India. He leads the team responsible for driving the growth and penetration of National Instruments products across industries and geographies in India. His areas of interest include Innovation, Test, Design, Measurement and Control solutions for Industry Modernization, Setting up Centers of Excellence for Academia. He holds an MBA from Manipal Academy for Higher Education, Manipal and a bachelor’s degree in electronics engineering from Mumbai University.