Control Level Factory Automation

In Industry 4.0 factory automation systems, devices are typically organized into three levels to support real-time communication and control:

1. Field Level: I/O modules, actuators, and drivers are responsible for the physical operations within the factory.
2. Control Level: Programmable Logic Controllers (PLC) or Computer Numerical Control (CNC) systems collect information from the field level and issue instructions to the field.
3. Operator Level: Human Machine Interface (HMI) devices interact with the operator, allowing them to issue commands.

Each level requires optimized hardware and software solutions to address the specific challenges it faces. The control level, in particular, presents significant design challenges, especially as the number of supported nodes increases, placing more demands on performance, power consumption, and reliability.

Design Challenges at the Control Level

As the number of supported nodes in a factory automation system increases, designers at the control level face unique challenges. A critical issue is how to support more nodes with fewer controllers, thus improving the cost-effectiveness of the automation system. This requires increased processor performance while keeping power consumption low to prevent increasing the size of the equipment. Additionally, most PLCs are designed without fans, so minimizing power loss is a key consideration in the design.

Real-Time Requirements

Since PLCs and CNC systems control a large number of nodes, their real-time performance is crucial. To achieve precise timing, solutions typically require two key components:

1. Real-Time Operating System (RTOS): Used for decision-making and controlling delays to meet critical timing requirements.
2. Flexible, Time-Aware Peripherals: Industrial communication peripherals that can respond to real-time demands, ensuring the system remains synchronized.

RTOS has been widely used in industrial control for many years, and there is increasing interest in RT Linux® solutions, which combine the time-awareness and decision-making capabilities needed for industrial automation applications with the advantages of the large open-source Linux community.

Multi-Protocol Support and Peripheral Interfaces

In industrial environments, it is common to need support for multiple fieldbus protocols, such as EtherCAT, PROFINET, and Ethernet/IP. Achieving multi-protocol compatibility can be complex, especially if each protocol requires its own dedicated ASIC, which adds to the complexity of the design. A more flexible approach involves programmable solutions where changes in fieldbus protocols can be handled via software or firmware updates.

Moreover, to ensure seamless real-time communication, controllers require a large number of peripheral interfaces. These interfaces need to communicate with the factory’s fieldbus network, I/O backplanes, actuators, drivers, and other controllers, as well as servers using protocols like OPC UA for data collection and diagnostic purposes. Ethernet interfaces play a vital role in supporting multi-protocol communication and high-efficiency data transfer.

TMDXIDK5728 Industrial Development Kit

For evaluating control-level factory automation solutions, the TMDXIDK5728 Industrial Development Kit based on the Sitara™ AM572x processor offers powerful support. The AM572x dual-core ARM® Cortex®-A15 processor is ideal for industrial applications because it supports an industrial temperature range, offers a lifespan of up to 100,000 hours, and provides real-time software support and a wide array of peripherals. Its integrated dual PRU-ICSS (Processor Real-Time Unit—Industrial Communication Subsystem) enables support for industrial communication protocols, making it suitable for multi-protocol environments.

The TMDXIDK5728 kit is equipped with four Ethernet ports, with two supporting gigabit switches and the other two coming from the PRU-ICSS (default configuration), or all four ports can be sourced from the PRU-ICSS. The kit supports the latest industrial fieldbus protocols through the PRU-ICSS-INDUSTRIAL-SW within Processor-SDK-RTOS. Additionally, it can run the Processor-SDK-Linux-RT software package, which provides an optimized RT Preempt patch for developing real-time industrial automation applications.

The TMDXIDK5728 makes it easy for developers to evaluate the real-time requirements of industrial automation applications and provides a flexible, programmable solution for multi-protocol support, making it an ideal choice for control-level applications in Industry 4.0 environments.