Introduction to Industrial Automation
Manufacturing involves using raw materials or parts to create goods or products that will be sold to customers. Creating products from raw materials can be done by using hand tools that are operated by humans or by machines such as motors, pumps, and drills, which are also operated by humans. Before machines, items/products were made by hand using tools, and lots of time and effort was spent producing a single item. The development of manufacturing resulted in hand tools being replaced by machines operated by humans, which made production faster with minimum effort. Nowadays, human involvement in terms of operating machines in manufacturing is being reduced or replaced via industrial automation.
By completing this chapter, you should be able to understand what industrial automation is and identify the various types of industrial automation that exist. You will also be able to describe the basic levels of industrial automation and identify the benefits of industrial automation in industries. Finally, you will be able to identify the cons of industrial automation in society.
In this chapter, we will cover the following topics:
- Introducing industrial automation
- Exploring the types of industrial automation
- Understanding the levels of industrial automation
- Discovering the advantages and disadvantages of industrial automation
Introducing industrial automation
A set of sequential operations are established in a factory where components are assembled to make a product or where materials are put through a refining process to produce an end product that is suitable for consumption (that is, a production line or assembly line). This usually consists of machines and tools that need to be operated to get the finished product. Before industrial automation, items (such as mugs, spoons, pots, and so on) were hand-made by individual craftsmen and women and it could take hours or days to manufacture a single item.
There was a development in the 18th century where, instead of items being produced by hand, processes were invented that allowed items to be produced by machines. These machines/tools were operated by humans. Hence, we can refer to the items that are produced through this process as man-machine made. This process dramatically reduces production time and costs compared to the hand-made method. A further shift in manufacturing was the introduction of assembly lines/production lines in the 19th century, which further reduced production time and costs as different workers could operate different machines in different sections of the production or assembly lines, leading to mass production. Nowadays, many factories have machines/tools in the production line being operated automatically by devices and control systems. Repetitive tasks such as filling, capping, and stamping are now automated.
A worker in a factory assembly line uses their eyes to see, their ears to hear, their brain to think, and their hands to move things or perform the required actions on the assembly line. With industrial automation, the activities/operations that are typically performed by the worker can be replaced by a control system where sensors do the job of the eyes and ears, a controller does the job of the brain, and an actuator does the job of the hands. Hence, sensors, controllers, and actuators, which we will look at in more detail in the subsequent chapters of this book, can replace a worker in a factory assembly line. In some manufacturing processes, an assembly line that requires one hundred staff members can eventually require just one or two people doing that through industrial automation. With the introduction of artificial intelligence (AI), machines that can even think like humans are being developed to handle human operations that we could not previously even imagine being handled by a machine.
Industrial automation can also be defined as being able to control machinery and equipment in an industry by using personal computers (PC), programmable logic controllers (PLCs), sensors, actuators, and other control devices to minimize the human involvement in the manufacturing or production processes. PCs, PLCs, and other forms of controllers replace human decision-making; the sensors replace the eyes and ears, while the actuators replace the hands, as explained previously. PCs, PLCs and other forms of controllers have programs (a set of instructions) written into them that enable them to make decisions based on the state of the sensors. The results of these decisions are used by the actuator to perform the action that the worker would have done.
The following figure shows an example of industrial automation using a KUKA industrial robot. Jobs, which are typically done by humans, are being carried out by robots (programmed machines):
Figure 1.1 – Industrial automation in a vehicle manufacturing assembly line using a KUKA industrial robot
This image is licensed under Wikimedia Commons: https://creativecommons.org/licenses/by-sa/4.0/deed.en.
Besides manufacturing, the transportation industry is another area where industrial automation can be applied, where self-operating vehicles are used for both private and commercial purposes – autopilot control in commercial jets enables jets to travel without human pilots. Warehouses, buildings, and other industries also benefit from industrial automation.
With that, you have learned that industrial automation involves using devices that operate machines automatically with little human involvement, which has significantly improved manufacturing and other industries. The knowledge you have acquired in this section will help you understand the various forms of automation we will look at in the next section.
Exploring the types of industrial automation
- Fixed automation system
- Programmable automation system
- Flexible automation system
- Integrated automation system
In the next few sections, you will discover what these categories are in detail. Let's have a look.
Fixed automation system
In a fixed automation system, the series of operations that must be performed on the raw material are fixed. This type of automation is used to perform fixed and repetitive operations to achieve high production rates. The machines involved are programmed or configured to produce a specific design for a product. Once adopted, it is relatively difficult to change the design or style of the product. Fixed automation systems are used when the same style of product is to be manufactured or assembled. The series of operations that are involved in the production or manufacturing process are designed or programmed based on the product. This type of automation system is characterized by a high production rate, high efficiency, and high initial cost and is suitable for manufacturing a large volume of products that will have a low cost per product.
- Paint and coating automation process
- Automatic assembly machines
- Bread production lines
- Steel rolling mills
- Metal pressing/stamping machines in a vehicle assembly line in the automobile industry
Let's have a look at programmable automation systems.
Programmable automation system
In a programmable automation system, the machines involved can be used to manufacture different styles of products. However, this requires reprogramming and changeover for each new style of product, which takes time to accomplish and creates downtime in production.
This type of automation is suitable for manufacturing where identical or similar styles of products are produced within a certain time frame. This is usually referred to as batch production. A long setup time is required to modify the program or reconfigure the sequence of operations for the new product design or batch to be manufactured.
Examples of programmable automation systems are as follows:
- Industrial robot: This is a type of robot (programmed machine) that's used in the manufacturing industry. It consists of a power supply, a controller, and a mechanical arm that can move in three or more axes. It can be programmed and configured for different kinds of tasks.
The following figure shows a robot designed to be able to do any work that can be programmed (within its limits and work envelope) simply by changing the program. Here, the robot was programmed for writing:
Figure 1.2 – KUKA industrial robot
This image is licensed under Wikimedia Commons: https://creativecommons.org/licenses/by-sa/4.0/deed.en.
- Computer Numerical Control (CNC) machine: This is a type of automated machine in which geometric code (G-code) and miscellaneous code (M-code), which are alphanumeric, form the basic program instructions for different kinds of tasks. This type of machine can automate drilling, milling, or 3D printing using a computer or controller.
Figure 1.3 – CNC vertical machining center (Kent CNC KVR 4020A)
Let's proceed to learn about flexible automation systems.
Flexible automation system
Flexible automation systems are an advanced form of programmable automation systems. They also require reprogramming and changeover for each new style of product, but this does not take time to accomplish as it is done in a programmable automation system. Hence, a flexible automation system reduces the downtime that's experienced in a programmable automation system. The product styles that a flexible automation system can produce are sufficiently limited so that the changeover can be accomplished very quickly and automatically. A flexible automation system allows a different range of products to flow through the line with little downtime.
Examples of flexible automation systems are as follows:
- Automated guided vehicles (AGVs): AGVs are vehicles without an onboard driver that are used mostly to transport materials/goods in a factory or warehouse. They can navigate along a pre-defined path using several guidance technologies, which makes it easy for them to change routes and expand the operation of the system in response to changes to a scalable and flexible material handling solution. AGVs can be used alongside an industrial robot to provide a very cost-effective material handling solution in a factory or warehouse. The AGV can transport pallets, cartons, and products that have been loaded onto it using an industrial robot, and then send them to various areas of the manufacturing facility or warehouse.
The following figure shows an example of an AGV:
Figure 1.4 – Automated guided vehicle by AIUT
This image is licensed under Wikimedia Commons: https://creativecommons.org/licenses/by-sa/4.0/deed.en.
- Flexible Assembly System (FAS): A FAS is an assembly system that can produce a variety of products in small to medium batches with rapid changeover and reprogramming for a new set of product designs or styles.
Let's now have a look at integrated automation systems.
Integrated automation system
As the name implies, an integrated automation system integrates various machines and tools such as CAD, robots, cranes, conveyors and other automated machineries to work under a single control system to execute an automation system of a production process. In this, separate machines, data, and processes are made to work together and controlled by a single control system. It allows the entire manufacturing plant to be automated and controlled by computers with less human intervention.
Integrated automation system is used in computer integrated manufacturing (CIM) in which computers control the entire production process with little human intervention. It is also used in various kinds of advanced process automation systems. Integrated automation system can give room for the implementation of various advanced technologies such as automated material handling systems, Radio Frequency Identification (RFID), barcode tracking systems, Manufacturing Execution System (MES), Computer Aided Process Planning (CAPP), automated conveyors and cranes, and many others.
In this section, you learned about the various types of industrial automation available while looking at relevant examples. This knowledge will help you have a better understanding of the next section and other topics that will be covered in this book.
Understanding the levels of industrial automation
Industrial automation is a complex system with several devices communicating and working with each other to provide the desired result. The simplest way to describe the levels/hierarchy of industrial automation is by using a three-level representation, as shown here:
- Field level
- Control level
- Supervisory and production level
We will describe each of these levels in the following section and provide the relevant examples for ease of understanding.
This is the lowest level in the hierarchy of industrial automation. It consists of field devices such as sensors and actuators, which are used in industrial automation. Sensors convert physical characteristics into electrical signals (digital or analog). They are input devices and can be referred to as the eyes and ears of automation. Examples of sensors include proximity sensors, temperature sensors, pressure sensors, level sensors, flow sensors, and limit switches. Actuators, on the other hand, convert electrical signals (digital or analog output signals) into physical characteristics, which can be in the form of motion. Examples include AC/DC motors, servo motors, stepper motors, pumps, control valves, solenoids, contactors, and relays. The job of the field devices (sensors and actuators) is to transfer machine and process data to the next level (control level) for monitoring and analysis.
This level can be referred to as the eyes and arms (hands) of an industrial automation system. The sensor is acting as the eyes, while the actuator is acting as the arms. Real-time process parameters such as temperature, pressure, level, and flow are converted into electrical signals by the sensors. Data that's collected from the sensors is transferred to the controller for further monitoring and analysis. The actuators control the process parameter through a signal from the controller.
This level consists of programmable logic controllers (PLCs) or other forms of controllers. PLCs are the brains behind modern industrial automation. They are used to carry out control functions in industries. They take data from different kinds of sensors, make decisions using the program written into it, and output a control signal that the actuator will use to carry out the required task. They can be programmed to deliver automatic control functions based on the signals they receive from sensors. More details on PLCs will be provided in Chapter 7, Understanding PLC Hardware and Wiring, and Chapter 8, Understanding PLC Software and Programming with TIA Portal.
Supervisory and production level
This level consists of Supervisory Control And Data Acquisition (SCADA) and Human Machine Interface (HMI), among others, for monitoring and controlling various parameters and setting production targets. Chapter 10, Understanding Human Machine Interfaces (HMIs), explains HMI while Chapter 11, Exploring Supervisory Control And Data Acquisition (SCADA), explains SCADA.
To help you gain a better understanding of HMI and SCADA, this book has been arranged to cover some basic knowledge of industrial automation before venturing into HMI and SCADA.
The following diagram represents the basic levels of industrial automation:
Figure 1.5 – Levels/hierarchy of industrial automation
In this section, you learned about the basic levels of industrial automation, which include the field level, the control level, and the supervisory and production level. Chapter 2, Switches and Sensors – Working Principles, Applications, and Wiring, and Chapter 3, Actuators and Their Applications in Industrial Automation, will give more detailed explanation on field level. Chapter 7, Understanding PLC Hardware and Wiring, Chapter 8, Understanding PLC Software and Programming Using the TIA Portal, and Chapter 9, Deep Dive into PLC Programming with TIA Portal, will give detailed explanation on the control level using hands-on approach while Chapter 11, Exploring Supervisory Control And Data Acquisition (SCADA), will further explain the supervisory and production level and include a hands-on project/practical project (interfacing SCADA with S7-1200 PLC using mySCADA software) that will give you a practical experience and understanding of the concept.
Discovering the advantages and disadvantages of industrial automation
There's no doubt that industrial automation has transformed manufacturing and other industries by allowing things to be done faster and better. Industrial automation is required for any industry to remain competitive. Although automation has led to great improvements in manufacturing and other industries, there are some negative effects of industrial automation that need to be looked into so that you are prepared and equipped to overcome them.
In the following sections, we will discover what these advantages and disadvantages are.
Advantages of industrial automation
- It reduces the time taken between starting and completing a process.
- It improves workers' safety. Automation saves workers from being exposed to hazardous environments in the factory.
- The use of robots in industrial automation increases production output. Robots can work 24/7 at a constant speed.
- Industrial automation reduces operating costs. Adding automated machines to an operation means less human effort (that is, fewer employees are needed to get the job done). Also, there will be less material waste due to the accuracy of the robots in performing a task.
- Industrial automation provides a faster return on investment (ROI) due to reduced processing time, reduced operating cost, increased production output, and so on.
- The use of automated guided vehicles (AGVs) and other automated machinery in the manufacturing industries reduces accidents that would have been caused by human error.
- Industrial automation allows managers to focus more on other aspects of their jobs since robots/automated systems require less supervision.
- Automated systems/robots don't get distracted, exhausted, or bored while working, so delays are eliminated and consistent performance can be expected.
Disadvantages of industrial automation
The following are some of the disadvantages of industrial automation:
- Industrial automation requires high initial capital (that is, the cost of designing, fabricating, installing, and commissioning automated systems is high).
- Industrial automation can get rid of jobs. Jobs done by humans can be taken over by an automated machine or robot. However, this might not necessarily be a disadvantage as the staff can be trained to service the machinery/ automated system or work in other areas of the business.
- Skilled personnel are required for maintaining and troubleshooting automated systems.
In this section, we learned how people and industries can benefit from industrial automation, as well as the various side effects of industrial automation. It is important to take these advantages and disadvantages into consideration when you are thinking about integrating automation technology in an industry.
Now that you have completed this chapter, which provided you with a basic understanding of industrial automation, you have achieved the first leg of this book's journey. Well done! You should now be able to explain industrial automation, describe the different types of industrial automation, describe the levels of industrial automation, and describe the advantages and disadvantages of industrial automation.
The topics that were covered in this chapter are relevant for automation engineers and will help you understand the next chapter, which will give you an overview of switches and sensors.
The following questions will help you test your understanding of this chapter. Ensure that you have read and understood the topics in this chapter before attempting these questions:
- _________________ is used to control machinery and equipment in an industry by using personal computers (PC), programmable logic controllers (PLCs), sensors, actuators, and other control devices to minimize the human involvement in the manufacturing or production processes.
- __________________ automation systems reduce the downtime that's experienced in programmable automation systems.
- In the hierarchy of industrial automation, the ____________________ level consists of PLCs or other form of controllers.
- ____________________ uses various forms of devices and control systems to operate machines and equipment that's used in manufacturing or processing plant with little human intervention.
- ______________________ is a set of sequential operations that's established in a factory where components are assembled to make a finished product or where materials are put through a refining process to produce an end product that is suitable for consumption.
- _________________, ________________________, and __________________ are the three types of industrial automation.
- A method of manufacturing where identical or similar style of products are produced together within a time frame is referred to as _________________.
- Vehicles without an on-board driver, which are used mostly to transport materials/goods in a factory or warehouse, are called ______________.
- In the industrial automation hierarchy, the ________________ level consists of sensors and actuators.
- _________________ convert electrical signals (digital or analog signals) into physical characteristics that can be in the form of motion or heat.
- ____________ convert physical characteristics into electrical signals (digital or analog).
- CNC is an acronym for _______________________.
- PLC is an acronym for ________________________.
- SCADA is an acronym for _____________________.
- HMI is an acronym for _______________________.