A Networked Control System (NCS) is a control system wherein the control loops are closed through a communication network.
The defining feature of an NCS is that control and feedback signals are exchanged among the system’s components in the form of information packages through a network.
The functionality of a typical NCS is established by the use of four basic elements:
- Sensors, to acquire information,
- Controllers, to provide decision and commands,
- Actuators, to perform the control commands and
- Communication network, to enable exchange of information.
The most important feature of a NCS is that it connects cyberspace to physical space enabling the execution of several tasks from long distance. In addition, networked control systems eliminate unnecessary wiring reducing the complexity and the overall cost in designing and implementing the control systems.
They can also be easily modified or upgraded by adding sensors, actuators and controllers to them with relatively low cost and no major changes in their structure. Moreover, featuring efficient sharing of data between their controllers, NCS are able to easily fuse global information to make intelligent decisions over large physical spaces.
Their potential applications are numerous and cover a wide range of industries such as: space and terrestrial exploration, access in hazardous environments, factory automation, remote diagnostics and troubleshooting, experimental facilities, domestic robots, aircraft, automobiles, manufacturing plant monitoring, nursing homes and tele-operations. While the potential applications of NCS are numerous, the proven applications are few, and the real opportunity in the area of NCS is in developing real-world applications that realize the area’s potential.
Types of communication networks
- Fieldbuses, e.g. CAN, LON etc.
- IP/Ethernet
- Wireless networks, e.g. Bluetooth or ZigBee or Zwave. The term Wireless Networked Control System (WNCS) is often used in this connection.