Automation, much like mechanization, depends on machines to execute functions many of which were first performed manually. Mechanization can be seen as the stepping stone between manual labor and automation—it eliminates the need for physical labor, but operators are still needed to oversee machine operations and provide maintenance and feedback. Automation systems, however, eliminate the need for an operator by including feedback and sensory programs. The result is highly independent machine systems that can carry out a task from start to finish, without human assistance.
Automated machines have been seamlessly integrated into countless industries, from carrying out manufacturing tasks to handling telephone switchboards. In quotidian life, we encounter automated systems each time we use an ATM. The level of human dependence is high, as is the functions we entrust them with—managing our finances, our phone calls, our computers. With such an array of functions, it’s not surprising that not all automated systems are the same. Depending on the exact function, one of several different tools may be responsible for an automated system: an artificial neural network, distributed control system, human machine interface, supervisory control and data acquisition, or a programmable logic controller.
Artificial Neural Network
An artificial neural network is a mathematical or computational model whose rhythms mimic those of biological neurons. The structure of the network is adaptive, meaning it can change based on the external or internal exchange of information throughout the network. Artificial neural networks are used to identify patterns in pools of data and to classify relationships (such as sequence recognition). Applications include e-mail spam filtering, system control (such as in a car), pattern recognition in systems (such as radars), pattern recognition in speech, movement, and text, and financial automated trading systems.
Distributed Control System
A distributed control system is one in which there are separate controls throughout the system. The controls are not centrally located, but tend to be spread out depending on which region of the system needs monitoring—each control is connected to the others in a communication network. These kinds of systems are typically used in manufacturing processes, especially when the action or production is continuous. The controllers can be specified for a given process, and manipulated to enhance or monitor machine performance. Traffic lights are usually controlled by distributed control systems, and they can also be applied in oil refining and central station power generation.
Human Machine Interface
Commonly referred to as a user interface, a human machine interface system depends on human interaction with the system in order to function. A user will provide input, and the system in turn will produce output that coincides with the user’s intent. In order for this to work, users must have access to the system and a means by which to manipulate it. ATMs, for example, are designed so users can easily dictate what the system is supposed to do while enabling it to easily respond and provide the appropriate results. Buttons that read withdrawal or make a deposit provide the user with any easy way to trigger a chain of commands within the internal system. The desired result, either the intake of a deposit or the ejection of cash, can then be achieved.
A supervisory control and data acquisition system (SCADA) is a larger, industrial control network that is often comprised of smaller sub-systems, including human machine interface systems connected to remote terminal units, which work to translate sensor signals into comprehensible data. These systems can work together to control an entire manufacturing site, or even an entire region by connecting several different manufacturing plants. SCADA systems bear a high resemblance to distributed control systems, and at times it may be difficult to differentiate between the two. The key difference lies in what they ultimately do—SCADA systems do not control each process in real time, rather they coordinate processes. Generally speaking, however, the two systems are highly similar and are often used in identical applications.
Programmable logic controllers are real time systems, meaning there is a set deadline and timeframe in which the desired result must be achieved. The PLC system is essentially a computer that controls manufacturing machines in an industrial production line, so it has multiple capabilities, such as varied temperature ranges and input and output settings, as well as the ability to weather dust and other unfavorable conditions. Programmable logic controllers can be used to program a variety of day-to-day applications, such as amusement park rides.
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