“To make this real-time communication solution more convenient and faster, the controllers require a large number of peripheral interfaces because they need to interface on multiple levels with the fieldbus network in the plant, backplanes to connect I/O, actuators, drives, or other Controllers, and those servers that use protocols such as OPC UA for data acquisition for plant diagnostics. All of this requires the use of a large number of peripheral interfaces, especially the Ethernet interface. In addition, a flexible and programmable communication solution is required.
A factory automation system for Industry 4.0 typically consists of three main layers of equipment that drive real-time communication and control:
At the control level, a Programmable Logic Controller (PLC) or Computer Numerical Control (CNC) is responsible for collecting information from the field level and issuing instructions to the field;
At the operator level, human-machine interface (HMI) devices communicate with the operator, who can issue commands.
Each layer requires optimized hardware and software solutions to address the tough design challenges it faces. Of these, challenges involving the control hierarchy are particularly difficult to address.
As the number of nodes supported by a single controller is gradually increasing, in addition to the challenges associated with all industrial automation designs such as power consumption, long power supply life, and reliability requirements, designers of control-level equipment face certain specific challenge. A higher number of supported nodes means that fewer controllers should be needed within the overall factory solution to create a more cost-effective automation solution, or these additional nodes can be used in the factory to achieve Higher degree of automation. However, as more and more nodes are supported, the performance of the processor must also increase year-on-year, while still keeping the power consumption low enough to avoid increasing the size of the package. Additionally, most PLCs are designed without fans, so power loss is a key design aspect.
Since PLCs and CNCs simultaneously control a large number of nodes or functions within a plant, the real-time nature of their operations is critical. Achieving precise timing requires two parts for a solution: a real-time operating system, and a flexible time-aware peripheral for industrial communications. Real-time operating systems (RTOS) are used in these devices to make decisions and control delays to meet critical timing requirements. Commercial RTOSs have been in widespread use in industrial control for several years, and there is growing interest in RT Linux® solutions that add the time-awareness and decision-making capabilities required by industrial automation applications. At the same time, it also has all the advantages of the large open source community of Linux.
For the communication peripheral part of the real-time solution, the main requirement is to support the bus protocol of the industrial field with a method that achieves low latency and short protocol cycle times even when the number of nodes needs to be increased. This becomes an even more complex problem when multiple fieldbus standards must be supported in a single design. Multi-protocol support is a must in order for the end product to be compatible with EtherCAT, PROFINET, Ethernet/IP and many other standards that may already be used in the factory. Achieving multi-protocol support through hardware (ASICs) is complex because each protocol may require its own specialized ASIC, and therefore each supported fieldbus requires a different board design. With a programmable approach, the problem might be simpler. In these methods, only software or firmware changes are required to implement fieldbus protocol changes.
To make this real-time communication solution more convenient and faster, the controllers require a large number of peripheral interfaces because they need to interface on multiple levels with the fieldbus network in the plant, backplanes to connect I/O, actuators, drives, or other Controllers, and those servers that use protocols such as OPC UA for data acquisition for plant diagnostics. All of this requires the use of a large number of peripheral interfaces, especially the Ethernet interface. In addition, a flexible and programmable communication solution is required.
The TMDXIDK5728 Industrial Development Kit (IDK) for Sitara™ AM572x processors is now available to evaluate control-level factory automation solutions. The AM572x dual-core ARM® Cortex®-A15 processor is ideal for industrial applications as it can support the industrial temperature range and achieve an exceptionally long lifetime of up to 100,000 hours, along with real-time software support and a large number of peripherals, For example dual PRU-ICSS (Processor Real Time Unit – Industrial Communication Subsystem) for programmable industrial communication. The TMDXIDK5728 provides 4 Ethernet ports, 2 of which can be from the Gigabit switch, the other 2 can be from the PRU-ICSS (default configuration), or all 4 ports can be from the PRU-ICSS. The TMDXIDK5728 enables the evaluation of TI’s newly released solutions for industrial fieldbus protocols based on the AM57x, which are provided by the PRU-ICSS-INDUSTRIAL-SW in the Processor-SDK-RTOS. In addition, the TMDXIDK5728 is available to run the Processor-SDK-Linux-RT package, which provides an optimized RT Preempt patch package on TI’s mainline Linux kernel for the development of real-time industrial automation applications.