To compete on a global scale and meet the growing demands for increased throughput, higher quality, and greater yield, the way the machine industry builds machines has evolved. The industry is enhancing purely mechanical systems, based on gears and cams, with electromechanical systems, which combine mechanical elements with advanced technologies such as electronic controls and motor drives into a single system.
These software-controlled electromechanical machines offer better accuracy and flexibility for increased throughput and yield. They also increase energy efficiency, resulting in both environmental and economical benefits. Yet electromechanical machines are difficult to design and manufacture.
Today’s designers must be familiar with a number of application areas and development tools, including mechanical design, embedded hardware, and software development. Meeting this multidisciplinary challenge requires improved development techniques, design tools, and embedded control technology.
Multiple Hardware Platforms Required There are three traditional platforms used for embedded machine control: programmable logic controllers (PLCs), single- board computers (SBCs), and custom-designed hardware. Each of these platforms has unique strengths and weaknesses.PLCs, for instance, are extremely rugged and reliable. They are programmed with an industry standard, are great for digital I/O, and have first-class connectivity to industrial networks, making it easy to connect to a variety of devices, such as motor drives. On the other hand, PLCs are unable to perform highspeed control and measurements, they don’t have very flexible software, and they’re a closed platform.
SBCs, which use a PC architecture and come in a variety of sizes and options, have the benefit of a large ecosystem with an extensive selection of products, such as I/O, that can be made to work with them. On the downside, these complementary products do not work out of the box and often require a significant integration effort. In addition, SBCs aren’t very packaged and often require custom enclosures.
Custom-designed hardware is a great option for applications requiring complete control over cost of goods or form factor. Designers use only the components that are necessary for the machine, optimizing performance and deployment costs. Unfortunately, custom hardware requires significant development time and resources for board bring-up. They also are much harder to maintain due to component ends-of-life.
Programmable automation controllers (PACs) combine the reliability and ruggedness of PLCs with the processing power and flexibility of PCs to provide a single platform that is optimized for machine control, monitoring, and logging. In addition, some PACs include programmable FPGAs, so machine builders benefit from custom hardware performance without having to build custom hardware.
By combining the strengths of all three traditional machine control platforms, PACs give machine designers a single-box solution for their complex machines, saving time and money on hardware development and integration.
Large Development Teams As today’s machines become more complex, the development teams that design and build them are required to do more and know additional, disjointed design tools. With budget pressures, increasing the pool of engineers that work on the machine is not always an option.The emergence of system-level development tools has allowed domain experts to perform tasks, such as programming an FPGA, that have typically required a hardware design engineer to complete. By abstracting the low-level implementation details and providing a common environment to develop all aspects of machine design, development teams can accomplish more with significantly fewer people and in less time.
Considering the various facets of embedded machine design, the domain expert traditionally develops the user interface, application algorithms, and hardware-based custom sensors and transducers. This leaves low-level tasks, such as developing drivers for operating systems, incorporating I/O hardware, and implementing buses to share data between multiple embedded systems, to the career embedded engineers.
With a system-level tool, however, the low-level tasks traditionally performed by career embedded engineers are abstracted and automated by high-level tools. Using software design tools that are tightly integrated with hardware platforms, incorporating real-time operating systems and I/O capabilities, domain experts can complete embedded machine designs without relying on specialized engineers, facilitating greater output with fewer people.
Graphical system design is an example of a system-level tool that is increasing productivity by providing the necessary approach and tools to expand the pool of engineers and scientists capable of embedded machine design. By standardizing on a single tool that spans so many application areas and hardware platforms, machine builders can focus on application development rather than spending valuable time on low-level programming and learning multiple development tools.