- WHAT IS PRODUCTION AND OPERATION MANAGEMENT:
Production is the creation of goods and services. Operations management (OM) is the set of activities that creates value in the form of goods and services by transforming inputs into outputs. Activities creating goods and services take place in all organizations. In manufacturing firms, the production activities that create goods are usually quite obvious.
Operations management refers to the systematic design, direction, and control of processes that transform inputs into services and products for internal, as well as external customers. A process is any activity or group of activities that takes one or more inputs, transforms them, and provides one or more outputs for its customers. For organizational purposes, processes tend to be clustered together into operations. An operation is a group of resources performing all or part of one or more processes. Processes can be linked together to form a supply chain, which is the interrelated series of processes within a firm and across different firms that produce a service or product to the satisfaction of customers. A firm can have multiple supply chains, which vary by the product or service provided. Supply chain management is the synchronization of a firm’s processes with those of its suppliers and customers to match the flow of materials, services, and information with customer demand. For example, Scholastic must schedule the printing of a very large quantity of books in a timely fashion, receive orders from its largest customers, directly load and dispatch a fleet of trucks by specific destination while bypassing regular warehouses, keep track of their progress using technology, and finally, bill their customers and collect payment. The operational planning at Scholastic, along with internal and external coordination within its supply chain, provides one example of designing customized processes for competitive operations.
In an organization that does not create a tangible good or product, the production function may be less obvious. We often call these activities services. The services may be “hidden” from the public and even from the customer. The product may take such forms as the transfer of funds from a savings account to a checking account, the transplant of a liver, the filling of an empty seat on an airplane, or the education of a student. Regardless of whether the end product is a good or service, the production activities that go on in the organization are often referred to as operations, or operations management.
- OPERATIONS IN THE ORGANIZATION
The operations function is central to the organization because it produces the goods and services which are its reason for existing, but it is not the only function. It is, however, one of the three core functions of any organization. These are:
- the marketing (including sales) function – which is responsible for communicating the organization’s products and services to its markets in order to generate customer requests for service;
- the product/service development function – which is responsible for creating new and modified products and services in order to generate future customer requests for service;
- the operations function – which is responsible for fulfilling customer requests for service through the production and delivery of products and services. In addition, there are the support functions which enable the core functions to operate effectively. These include, for example:
- the accounting and finance function – which provides the information to help economic decision-making and manages the financial resources of the organization;
- The human resources function – which recruits and develops the organization’s staff as well as looking after their welfare.
Almost all organizations, however, will have the three core functions, because all organizations have a fundamental need to sell their services, satisfy their customers and create the means to satisfy customers in the future. In practice, there is not always a clear division between the three core functions or between core and support functions. This leads to some confusion over where the boundaries of the operations function should be drawn. In this book we use a relatively broad definition of operations. We treat much of the product/service development, technical and information systems activities and some of the human resource, marketing, and accounting and finance activities as coming within the sphere of operations management. We view the operations function as comprising all the activities necessary for the day-to-day fulfillment of customer requests. This includes sourcing products and services from suppliers and transporting products and services to customers. Working effectively with the other parts of the organization is one of the most important responsibilities of operations management. It is a fundamental of modern management that functional boundaries should not hinder efficient internal processes. Operations management’s responsibility to support functions is primarily to make sure that they understand operations’ needs and help them to satisfy these needs. The relationship with the other two core functions is more equal – less of ‘this is what we want’ and more ‘this is what we can do currently – how do we reconcile this with broader business needs?’
Fig1: The relationship between the operations function and other core and support functions of the organization
A core process is a set of activities that delivers value to external customers. Managers of these processes and their employees interact with external customers and build relationships with them, develop new services and products, interact with external suppliers, and produce the service or product for the external customer. Examples include a hotel’s reservation handling, a new car design for an auto manufacturer, or Web-based purchasing for an online retailer like amazon.com. Of course, each of the core processes has nested processes within it. In this text we focus on four core processes:
- Supplier Relationship Process. Employees in the supplier relationship process select the suppliers of services, materials, and information and facilitate the timely and efficient flow of these items into the firm. Working effectively with suppliers can add significant value to the services or products of the firm. For example, negotiating fair prices, scheduling on-time deliveries, and gaining ideas and insights from critical suppliers are just a few of the ways to create value.
- New Service/Product Development Process. Employees in the new service/product development process design and develop new services or products. The services or products may be developed to external customer specifications or conceived from inputs received from the market in general.
- Order Fulfillment Process. The order fulfillment process includes the activities required to produce and deliver the service or product to the external customer.
- Customer Relationship Process, sometimes referred to as customer relationship management. Employees involved in the customer relationship process identify, attract, and build relationships with external customers, and facilitate the placement of orders by customers. Traditional functions, such as marketing and sales, may be a part of this process.
A support process provides vital resources and inputs to the core processes and is essential to the management of the business. Firms have many support processes. Examples include budgeting, recruiting, and scheduling. Support processes provide key resources, capabilities, or other inputs that allow the core processes to function. The Human Resources function in an organization provides many support processes such as recruiting and hiring workers who are needed at different levels of the organization, training the workers for skills and knowledge needed to properly execute their assigned responsibilities, and establishing incentive and compensation plans that reward employees for their performance. The legal department puts in place support processes that ensure that the firm is in compliance with the rules and regulations under which the business operates. The Accounting function supports processes that track how the firm’s financial resources are being created and allocated over time, while the Information Systems function is responsible for the movement and processing of data and information needed to make business decisions.
- OPERATIONS STRATEGY
Fig 2: Connection Between Corporate Strategy and Key Operations Management Decisions
Operations strategy specifies the means by which operations implements corporate strategy and helps to build a customer-driven firm. It links long-term and short-term operations decisions to corporate strategy and develops the capabilities the firm needs to be competitive. It is at the heart of managing processes and supply chains. A firm’s internal processes are only building blocks: They need to be organized to ultimately be effective in a competitive environment.
Operations strategy is the linchpin that brings these processes together to form supply chains that extend beyond the walls of the firm, encompassing suppliers as well as customers. Since customers constantly desire change, the firm’s operations strategy must be driven by the needs of its customers. Developing a customer-driven operations strategy begins with corporate strategy, which, as shown in Figure 1.5, coordinates the firm’s overall goals with its core processes. It determines the markets the firm will serve and the responses the firm will make to changes in the environment.
It provides the resources to develop the firm’s core competencies and core processes, and it identifies the strategy the firm will employ in international markets. Based on corporate strategy, a market analysis categorizes the firm’s customers, identifies their needs, and assesses competitors ‘strengths. This information is used to develop competitive priorities. These priorities help managers develop the services or products and the processes needed to be competitive in the marketplace. Competitive priorities are important to the design of existing as well as new services or products, the processes that will deliver them, and the operations strategy that will develop the firm’s capabilities to fulfill them. Developing a firm’s operations strategy is a continuous process because the firm’s capabilities to meet the competitive priorities must be periodically checked and any gaps in performance must be addressed in the operations strategy
- 10 CRITICAL DECISION:
- Design of goods and services:
- Managing quality
- Process and capacity design
- Location strategy
- Layout strategy
- Human resources and job design
- Supply chain management
- Inventory management
Fig 3: Connection Between Corporate Strategy and Key Operations Management Decision
- PROCESS STRATEGY:
A process involves the use of an organization’s resources to provide something of value. No service can be provided and no product can be made without a process, and no process can exist without at least one service or product. One recurring question in managing processes supply chain processes Business processes that have external customers or suppliers is deciding how to provide services or make products. Many different choices are available in selecting human resources, equipment, outsourced services, materials, work flows, and methods that transform inputs into outputs.
Fig 4: Major Decisions for Effective Processes
Another choice is which processes are to be done in-house, and which processes are to be outsourced—that is, done outside the firm and purchased as materials and services. This decision helps to define the supply chain, and is covered more fully in subsequent chapters. Supplement A, “Decision Making Models,” also introduces make-or-buy break-even.
Process decisions directly affect the process itself and indirectly the services and the products that it provides. Whether dealing with processes for offices, service providers, or manufacturers, operations managers must consider four common process decisions. Figure 3.1 shows that they are all important steps toward an effective process design. These four decisions are best understood at the process or sub-process level, rather than at the firm level.
- Process structure determines the process type relative to the kinds of resources needed, how resources are partitioned between them, and their key characteristics. A layout, which is the physical arrangement of operations created from the various processes, puts these decisions into tangible form.
- Customer involvement reflects the ways in which customers become part of the process and the extent of their participation.
- Resource flexibility is the ease with which employees and equipment can handle a wide variety of products, output levels, duties, and functions.
- Capital intensity is the mix of equipment and human skills in a process. The greater the relative cost of equipment, the greater is the capital intensity.
The concepts that we develop around these four decisions establish a framework within which we can address the appropriate process design in every situation. There is no “how to” element here in this chapter. That comes in subsequent chapters that show how to actually design the processes or modify existing ones. Instead, we establish the patterns of choices that create a good fit between the four decisions. For example, if you walk through a manufacturing facility where materials flow smoothly from one work station to the next (which we will define later to be a line process), you would be tempted to conclude that all processes should be line processes. They seem so efficient and organized. However, if volumes are low and the products made are customized, converting to a line process would be a big mistake. When volumes are low and products are customized, resources must be more flexible to handle a variety of products. The result is a more disorganized appearance with jobs crisscrossing in many different direct.
A process strategy is an organization’s approach to transforming resources into goods and services. The objective is to create a process that can produce offerings that meet customer requirements within cost and other managerial constraints.
The process selected will have a long-term effect on efficiency and flexibility of production, as well as on cost and quality of the goods produced. Virtually every good or service is made by using some variation of one of four process
- Process focus,
- Repetitive focus,
- Product focus,
- Mass customization.
The relationship of these four strategies to volume and variety is shown in Figure 5
Fig 5: Four Process Options
- Process focus:
The vast majority of global production is devoted to making low-volume, high-variety products in places called “job shops.” Such facilities are organized around specific activities or processes. In a factory, these processes might be departments devoted to welding, grinding, and painting. In an office, the processes might be accounts payable, sales, and payroll. In a restaurant, they might be bar, grill, and bakery. Such facilities are process focused in terms of equipment, layout, and supervision. They provide a high degree of product flexibility as products move between the specialized processes. Each process is designed to perform a variety of activities and handle frequent changes. Consequently, they are also called intermittent processes.
- Facilities are organized around specific activities or processes (In factory, these processes might be departments devoted to welding, grinding and painting.)
- General purpose equipment and skilled personnel
- High degree of product flexibility
- Typically high costs and low equipment utilization
- Product flows may vary considerably making planning and scheduling a challenge
2. Repeatitive focus:
Repetitive processes, as we saw in the Global Company Profile on Harley-Davidson, use modules (see Figure 7.2 b). Modules are parts or components previously prepared, often in a product focused (continuous) process. The repetitive process is the classic assembly line. Widely used in the assembly of virtually all automobiles and household appliances, it has more structure and consequently less flexibility than a process-focused facility.
- Facilities often organized as assembly lines
- Characterized by modules with parts and assemblies made previously
- Modules may be combined for many output options
- Less flexibility than process-focused facilities but more efficient
3. Product focus:
High-volume, low-variety processes are product focused. The facilities are organized around products. They are also called continuous processes because they have very long, continuous production runs. Products such as glass, paper, tin sheets, lightbulbs, beer, and potato chips are made via a continuous process. Some products, such as lightbulbs, are discrete; others, such as rolls of paper, are made in a continuous flow.
An organization producing the same lightbulb or hot dog bun day after day can organize around a product. Such an organization has an inherent ability to set standards and maintain a given quality, as opposed to an organization that is producing unique products every day, such as a print shop or general-purpose hospital. A product-focused facility produces high volume and low variety. The specialized nature of the facility requires high fixed cost, but low variable costs reward high facility utilization.
- Facilities are organized by product
- High volume but low variety of products
- Long, continuous production runs enable efficient processes
- Typically high fixed cost but low variable cost
- Generally less skilled labor
4. Mass Customization focus:
Operations managers use mass customization to produce this vast array of goods and services. Mass customization is the rapid, low-cost production of goods and services that fulfill increasingly unique customer desires. But mass customization is not just about variety; it is about making precisely what the customer wants when the customer wants it economically. Mass customization brings us the variety of products traditionally provided by low- volume manufacture (a process focus) at the cost of standardized high-volume (product-focused) production. However, achieving mass customization is a challenge that requires sophisticated operational capabilities. Building agile processes that rapidly and inexpensively produce custom products requires a limited product line and modular design. The link between sales, design, production, supply chain, and logistics must be tight.
- The rapid, low-cost production of goods and service to satisfy increasingly unique customer desires
- Combines the flexibility of a process focus with the efficiency of a product focus
Fig 6: Four Process Options with an Example of Each
- DECISION PATTERNS FOR MANUFACTURING PROCESSES
Just as a service process can be re positioned in the customer-contact matrix, a manufacturing process can also be moved in the product-process matrix. Changes can be made either in the horizontal direction of Figure 3.3 by changing the degree of customization and volume, or they can be moved in the vertical direction by changing process divergence. The production and inventory strategy can also be changed. Competitive priorities must be considered when translating strategy into specific manufacturing processes. Figure 7 shows some usual tendencies found in practice. Job and small batch processes are usual choices if top quality, on-time delivery, and flexibility (customization, variety, and volume flexibility) are given primary emphasis. Large batch, line, and continuous-flow processes match up with an emphasis on low-cost operations, consistent quality, and delivery speed. For production and inventory strategies, the make-to-order strategy matches up with flexibility (particularly customization) and top quality. Because delivery speed is more difficult, meeting due dates and on-time delivery get the emphasis on the time dimension. The assemble-to-order strategy allows delivery speed and flexibility (particularly variety) to be achieved, whereas the make-to-stock strategy is the usual choice if delivery speed and low-cost operations are emphasized. Keeping an item in stock assures quick delivery because it is generally available when needed, without delays in producing it. High volumes open up opportunities to reduce costs.
The process structure selected once again points the way to appropriate choices on customer involvement, resource flexibility, and capital intensity.
- Process Structure. High volumes, combined with a standard product, make a line flow possible. It is just the opposite where a job process produces to specific customer orders.
- Customer Involvement. Customer involvement is not a factor in most manufacturing processes, except for choices made on product variety and customization. Less discretion is allowed with line or continuous flow processes in order to avoid the unpredictable demands required by customized orders.
- Resource Flexibility. When volumes are high and process divergence is low, flexibility is not needed to utilize resources effectively, and specialization can lead to more efficient processes.
- Capital Intensity. High volumes justify the large fixed costs of an efficient operation. The King Soopers’s bread line is capital-intensive. It is automated from dough mixing to placement of the product on shipping racks. Expanding this process would be expensive. By way of contrast, the King Soopers’s custom cake process is labor-intensive and requires little investment to equip the workers.
Fig 7: Decision Patterns for Manufacturing Process
- PROCESS DESIGN AND ANALYSIS
When analyzing and designing processes, we ask questions such as the following:
◆ Is the process designed to achieve competitive advantage in terms of differentiation, response, or low cost?
◆ Does the process eliminate steps that do not add value?
◆ Does the process maximize customer value as perceived by the customer?
◆ Will the process win orders?
Process analysis and design not only addresses these issues, but also related OM issues such as throughput, cost, and quality. Process is key. Examine the process; then continuously improve the process. The following tools help us understand the complexities of process design and redesign. They are simply ways of making sense of what happens or must happen in a process. We now look at: flowcharts, time-function mapping, process charts, value-stream mapping, and service blueprinting.
- Flow Diagrams/ Flow chart – Shows the movement of materials
- Time-Function Mapping – Shows flows and time frame
- Value-Stream Mapping – Shows flows and time and value added beyond the immediate organization
- Process Charts – Uses symbols to show key activities
- Service Blueprinting – focuses on customer/provider interaction
7.1 Flow Diagrams/ Flow chart
A flowchart traces the flow of information, customers, equipment, or materials through the various steps of a process. Flowcharts are also known as flow diagrams, process maps, relationship maps, or blueprints. Flowcharts have no precise format and typically are drawn with boxes (with a brief description of the step inside), and with lines and arrows to show sequencing. The rectangle (n) shape is the usual choice for a box, although other shapes (,, , , or ) can differentiate between different types of steps (e.g., operation, delay, storage, inspection, and so on). Colors and shading can also call attention to different types of steps, such as those particularly high on process divergence. Divergence is also communicated when an outgoing arrow from a step splits into two or more arrows that lead to different boxes. Although many representations are acceptable, there must be agreement on the conventions used. They can be given as a key somewhere in the flowchart, and/or described in accompanying text. It is also important to communicate what (e.g., information, customer order, customer, materials, and so on) is being tracked.
Fig 8: Flowchart of the Nested Sub-process of Client Agreement and Service Delivery
Fig 9: Swim Lane Flowchart of the Order-Filling Process Showing Handoffs Between Departments
Fig 10: Flowchart of the harley daivson
7.3 Time function mapping:
A second tool for process analysis and design is a modified flowchart with time added on the horizontal axis. Such charts are sometimes called time-function mapping, or process mapping. With time-function mapping, nodes indicate the activities, and the arrows indicate the flow direction, with time on the horizontal axis. This type of analysis allows users to identify and eliminate waste such as extra steps, duplication, and delay. Figure 11 shows the use of process mapping before and after process improvement at American National Can Company. In this example, substantial reduction in waiting time and process improvement in order processing contributed to a savings of 46 days.
Fig 11: Swim Lane Flowchart of the Order-Filling Process Showing Handoffs Between Departme
7.4 Process Charts:
The third tool is the process chart. Process charts use symbols, time, and distance to provide an objective and structured way to analyze and record the activities that make up a process. 1 They allow us to focus on value-added activities. For instance, the process chart shown in Figure which includes the present method of hamburger assembly at a fast-food restaurant, includes a value-added line to help us distinguish between value-added activities and waste. Identifying all
Value-added operations (as opposed to inspection, storage, delay, and transportation, which add no value) allows us to determine the percent of value added to total activities. 2 We can see from the computation at the bottom of Figure 7.5 that the percentage of value added in this case is 85.7%
Fig 11: Example of flow charts
7.5 Value Stream mapping:
A variation of time-function mapping is value-stream mapping (VSM); however, value-stream mapping takes an expanded look at where value is added (and not added) in the entire production process, including the supply chain. As with time-function mapping, the idea is to start with the customer and understand the production process, but value-stream mapping extends the analysis back to suppliers.
Value-stream mapping takes into account not only the process but, as shown in Example 2 also the management decisions and information systems that support the process.
Motorola has received an order for 11,000 cell phones per month and wants to understand how the order will be processed through manufacturing.
APPROACH à To fully understand the process from customer to supplier, Motorola prepares a value stream map.
SOLUTION àalthough value-stream maps appear complex, their construction is easy. Here are the steps needed to complete the value-stream map shown in Figure.
- Begin with symbols for customer, supplier, and production to ensure the big picture.
- Enter customer order requirements.
- Calculate the daily production requirements.
- Enter the outbound shipping requirements and delivery frequency.
- Determine inbound shipping method and delivery frequency.
- Add the process steps (i.e., machine, assemble) in sequence, left to right.
- Add communication methods, add their frequency, and show the direction with arrows.
- Add inventory quantities (shown with) between every step of the entire flow.
- Determine total working time (value-added time) and delay (non-value-added time).
Fig 12: Example of Value Stream Mapping
7.6 Service Blue Printing:
Products with a high service content may warrant use of yet a fifth process technique. Service blueprinting is a process analysis technique that focuses on the customer and the provider’s interaction with the customer. For instance, the activities at level one of Figure are under the control of the customer. In the second level are activities of the service provider interacting with the customer. The third level includes those activities that are performed away from, and not immediately visible to, the customer. Each level suggests different management issues. For instance, the top level may suggest educating the customer or modifying expectations, whereas the second level may require a focus on personnel selection and training. Finally, the third level lends itself to more typical process innovations. The service blueprint shown in Figure 7.7 also notes potential failure points and shows how poka-yoke techniques can be added to improve quality. The consequences of these failure points can be greatly reduced if identified at the design stage when modifications or appropriate poka-yokes can be included. A time dimension is included in Figure to aid understanding, extend insight, and provide a focus on customer service.
A good design for service processes depends first and foremost on the type and amount of customer contact. A service blueprint is a special flowchart of a service process that shows which steps have high customer contact. It uses a line of visibility to identify which steps are visible to the customer (and thus. more of a front-office process) and those that are not (back office process). Another approach to creating a service blueprint is to create three levels. The levels clarify
how much control the customer has over each step. For example, consider a customer driving into a Fast Lube shop to have their car serviced. Level 1 would be when the customer is in control, such as driving in for service or paying the bill at the end. Level 2 could be when the customer interacts with the service provider, such as making the initial service request, or being notified on what needs to be done. Level 3 could be when the service is removed from the customer’s control, such as when the work is performed and the invoice is prepared.
Fig 132: Example of Service Blue Printing
- PRODUCTION TECHNOLOGY:
Advances in technology that enhance production and productivity are changing how things are designed, made, and serviced around the world. In this section, we introduce nine areas of technology:
(1) Machine technology,
(2) Automatic identification systems (AIS),
(3) Process control,
(4) Vision systems,
(6) Automated storage and retrieval systems (ASRSs),
(7) automated guided vehicles (AGVs),
(8) Flexible manufacturing systems (FMSs), and
(9) computer-integrated manufacturing (CIM).
Consider the impact on operations managers as we digitally link these technologies within the firm. Then consider the implications when they are combined and linked globally in a seamless chain that can immediately respond to changing consumer demands, supplier dynamics, and producer innovations. The implications for the world economy and OM are huge
8.1 Machine Technology:
Much of the world’s machinery performs operations by removing material, performing operations such as cutting, drilling, boring, and milling. This technology is undergoing tremendous progress in both precision and control. Machinery now turns out metal components that vary less than a micron—1/76 the width of a human hair. They can accelerate water to three times the speed of sound to cut titanium for surgical tools. Such machinery is often five times more productive than that of previous generations while being smaller and using less power. And continuing advances in lubricants now allow the use of water-based lubricants rather than oil-based. Water-based lubricants enhance sustainability by eliminating hazardous waste and allowing shavings to be easily recovered and recycled.
Computer intelligence often controls this new machinery, allowing more complex and precise items to be made faster. Such machinery, with its own computer and memory, is referred to as having computer numerical controls (CNC). Electronic controls increase speed by cutting changeover time, reducing waste (because of fewer mistakes), and enhancing flexibility. Advanced versions of such technology are used on Pratt & Whitney’s turbine blade plant in Connecticut. The machinery has improved the loading and alignment task so much that Pratt has cut the total time for the grinding process of a turbine blade from 10 days to 2 hours. The new machinery has also contributed to process improvements that mean the blades now travel just 1,800 feet in the plant, down from 8,100 feet, cutting throughput time from 22 days to 7 days. New advances in machinery suggest that rather than removing material as has traditionally been done, adding material may in many cases be more efficient. Additive manufacturing or, as it is commonly called, 3D printing, is frequently used for design testing, prototypes, and custom products. The technology continues to advance and now supports innovative product design (variety and complexity), minimal custom tooling (little tooling is needed), minimal assembly (integrated assemblies can be “printed”), low inventory (make-to-order systems), and reduced time to market. As a result, additive manufacturing is being increasingly used to enhance production efficiency for high-volume products. In addition, production processes using numerous materials including plastics, ceramics, and even a paste of living cells are being developed. The convergence of software advances, computer technology, worldwide communication, and 3D printing seems to be putting us on the cusp of true mass customization. We can expect personalized mass markets via additive manufacturing to bring enormous changes to operations.
8.2 Automatic Identification Systems (AISs) and RFID:
New equipment, from numerically controlled manufacturing machinery to ATMs, is controlled by digital electronic signals. Electrons are a great vehicle for transmitting information, but they have a major limitation—most OM data does not start out in bits and bytes. Therefore, operations managers must get the data into an electronic form. Making data digital is done via computer keyboards, bar codes, radio frequencies, optical characters, and so forth. These automatic identification systems (AISs) help us move data into electronic form, where it is easily manipulated. Because of its decreasing cost and increasing pervasiveness, radio frequency identification (RFID) warrants special note. RFID is integrated circuitry with its own tiny antennas that use radio waves to send signals a limited range—usually a matter of yards. These RFID tags provide unique identification that enables the tracking and monitoring of parts, pallets, people, and pets—virtually everything that moves. RFID requires no line of sight between tag and reader.
8.3 Process Control:
Process control is the use of information technology to monitor and control a physical process. For instance, process control is used to measure the moisture content and thickness of paper as it travels over a paper machine at thousands of feet per minute. Process control is also used to determine and control temperatures, pressures, and quantities in petroleum refineries, petrochemical processes, cement plants, steel mills, nuclear reactors, and other product-focused facilities.
Process control systems operate in a number of ways, but the following are typical:
◆ Sensors collect data, which is read on some periodic basis, perhaps once a minute or second.
◆ Measurements are translated into digital signals, which are transmitted to a computer.
◆ Computer programs read the file and analyze the data.
◆ The resulting output may take numerous forms.
These include messages on computer consoles or printers, signals to motors to change valve settings, warning lights or horns, or statistical process control charts.
8.4 Vision System:
Vision systems combine video cameras and computer technology and are often used in inspection roles. Visual inspection is an important task in most food-processing and manufacturing organizations. Moreover, in many applications, visual inspection performed by humans is tedious, mind-numbing, and error prone. Thus vision systems are widely used when the items being inspected are very similar. For instance, vision systems are used to inspect Frito-Lay’s potato chips so that imperfections can be identified as the chips proceed down the production line. The systems are also used to ensure that sealant is present and in the proper amount on Whirlpool’s washing machine transmissions. Vision systems are consistently accurate, do not become bored, and are of modest cost. These systems are vastly superior to individuals trying to perform these tasks.
8.5 Robots System:
When a machine is flexible and has the ability to hold, move, and perhaps “grab” items, we tend to use the word robot. Robots are mechanical devices that use electronic impulses to activate motors and switches. Robots may be used effectively to perform tasks that are especially monotonous or dangerous or those that can be improved by the substitution of mechanical for human effort. Such is the case when consistency, accuracy, speed, strength, or power can be enhanced by the substitution of machines for people. The automobile industry, for example, uses robots to do virtually all the welding and painting on automobiles. And a new, more sophisticated, generation of robots are fitted with sensors and cameras that provide enough dexterity to assemble, test, and pack small parts.
8.6 Automated Storage and Retrieval Systems (ASRSs):
Because of the tremendous labor involved in error-prone warehousing, computer-controlled warehouses have been developed. These systems, known as automated storage and retrieval systems (ASRSs), provide for the automatic placement and withdrawal of parts and products into and from designated places in a warehouse. Such systems are commonly used in distribution facilities of retailers such as Walmart, Tupperware, and Benetton. These systems are also found in inventory and test areas of manufacturing firms
8.7 Automated Guided Vehicles (AGVs):
Automated material handling can take the form of monorails, conveyors, robots, or automated guided vehicles. Automated guided vehicles (AGVs) are electronically guided and controlled carts used in manufacturing and warehousing to move parts and equipment. They are also used in agriculture to distribute feed, in offices to move mail, and in hospitals and jails to deliver supplies and meals.
8.8 Flexible Manufacturing Systems (FMSs)
When a central computer provides instructions to each workstation and to the material handling equipment such as robots, ASRSs, and AGVs (as just noted), the system is known as an automated work cell or, more commonly, a flexible manufacturing system (FMS). An FMS is flexible because both the material-handling devices and the machines themselves are controlled by easily changed electronic signals (computer programs). Operators simply load new programs, as necessary, to produce different products. The result is a system that can economically produce low volume but high variety. For example, the Lockheed Martin facility, near Dallas, efficiently builds one-of-a-kind spare parts for military aircraft. The costs associated with changeover and low utilization have been reduced substantially. FMSs Bridge the gap between product-focused and process-focused facilities
8.9 Computer-Integrated Manufacturing (CIM)
Flexible manufacturing systems can be extended backward electronically into the engineering and inventory control departments and forward to the warehousing and shipping departments. In this way, computer-aided design (CAD) generates the necessary electronic instructions to run a numerically controlled machine. In a computer-integrated manufacturing environment, a design change initiated at a CAD terminal can result in that change being made in the part produced on the shop floor in a matter of minutes. When this capability is integrated with inventory control, warehousing, and shipping as a part of a flexible manufacturing system, the entire system is called computer-integrated manufacturing (CIM)
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