Computer-Aided Design in Mechanical Engineering - Case Study Example

Computer Aided Manufacturing Computer Aided Manufacturing (CAM) Manufacturing is the process of producing goods for use by people using available resources. The manufacturing process employs the use of labor, tool and machines and various chemical and biological processes to make products for use by the general population. The term manufacture is often used to refer to industrial processes, which are often in large scale. However, the handicraft industry can also be included as a manufacturing process. During the industrial revolution that took place in Britain, man started to use tools and machinery to produce goods in large scale. This lowered the cost of production per unit and enabled the production of goods that were cheap and could be bought by the general population. Ever since, the manufacturing process has undergone tremendous improvements, which has led to improved efficiency and lowered the cost of production further. The improvements in the electronics and computer design have led to the development of computer-controlled control systems. These systems are advantageous over previously used systems as they can be easily manipulated to change the output. Introduction Computer Aided Manufacturing (CAM) refers to the use of Numerical Control (NC) software applications to create G-code, which are the instructions fed to numerical control machines to produce the required output. The use of CAM has led to the production of high quality products. CAM can also be defined as the process of producing a manufacturing plan for the design of tools and models, and coordinating the machines, and simulation. The plan is then carried out on the production line. For machines to operate, they require a form of control. There are various types of control mechanism available including manual control, automatic control and computer control. Machines used for mass production are often expected to produce to repeat similar operations precisely and fast. They should repeat these processes repeatedly. This requires automation to improve the speed of these processes. Common techniques that are used in the control systems of machines include electrical systems, pneumatic systems, and mechanical systems. For such systems, if a change is required, the procedures necessary to effect the change are long, tedious, and expensive. Advances in computer and electronic technologies have been employed to design systems that are more flexible. The use of these technologies leads to an increase in the efficiency of machinery produced. The products produced are of better quality and are cheaper (Elanchezhan, Sunder & Shanmuga, 2007). Numerical Machines The use of the computer to aid manufacturing is carried out using numerical machines. A numerical machine is connected to a computer, and it accepts digital input from the computer to control the machine parts. To change some values of the design, the computer program is the only part of the system that is changing. Modification of the program is quick and easy compared to changing machine parts manually. Furthermore, the program can be simulated on a computer to check if it operates as required before being imported on to the machine. The use of Computer Controlled Numerical Machines is closely related to the use of computer aided design or (CAD). This is because the output from the CAD if often required simplifying the CAM process. Advantages of CAM i. Use of CNC machines leads to high repeatability and precision. ii. It leads to the production of a large number of products. iii. The system is flexible and allows changes to the output. iv. It leads to ease production of complex contours. v. The production process is safe, and leads to the production of better quality products. vi. Reduces the number of scraps as the design can be simulated before the system is tested. vii. Less paper work is required to finalize the design of the manufacturing process. viii. Leads to a reduction in the lead-time. Lead-time refers to the amount of time necessary for the production of an item. Disadvantages of CAM i. The initial set up is costly. ii. The system requires skilled operators and training costs are incurred. iii. To operate and program the machines, one must have knowledge on computers. iv. The maintenance of these systems is difficult. CAM processes are mostly used in the production of goods on a large scale. The use of CAM for industrial use leads to higher productivity. As seen earlier, CAM systems lead to better quality products. The high precision and repeatability of these systems is advantageous in mass production. These machines run for 24 hours a day, producing similar products of high quality. Due to the high efficiency, the very few of the products are defective and cannot pass quality control tests. The result is higher productivity. The number of scrapes and defective products is low, and the company does not incur additional costs for the disposal of these products. Another advantage is that the CAM systems were designed for mass production. Therefore, the design and functionality of these systems are enhanced when they are used to manufacture a large quantity of products. The initial high cost of installing the system is justified by this fact. The cost of the machine is soon recovered by the company and it starts earning a profit. The lifetime of the machine is usually long. A machine that produces a large number of products efficiently is essential for the long time goals of a company. The company is ensured of a profitable future. The CAM systems allow the programmers a chance to simulate their code before testing it on the machine. This reduces the amount of hours required to test the system on the machine. This leads to lower costs for the company as these hours are used to produce quality products. If the system is not simulated before being tested, there is a higher likelihood for the code to contain undetected errors in the G-code. CAM processes lead to improved safety. This is because before the code is imported into the machine, it is vigorously tested and simulation carried out. This avoids mistakes to be carried to the machine. Some errors in code can lead to disastrous outcome and therefore testing the code is an important step. When producing a large number of products, time is a big factor and is expensive. If the machine breaks down in the course of production, it leads to losses. If the CAM system is used to produce a low batch of quantities, the major advantage of the system would be the manufacture of high quality products. Due to the inherent advantages of a computer controlled control system, the low number of products would mean that more time is taken in developing the code. The amount of the time dedicated to the production of these few goods increased. A lot of care is taken and the end product is of high quality. Another advantage is the ability to produce a small number of products each of which slightly differs from the other. This is achievable because CAM systems are flexible. The machines can be loaded with different programs for each product. Therefore, they are capable of producing goods easily and at a lower cost than manually controlled system. However due to the large cost of installing the system, producing a small number of products relates to larger cost of production per unit. If the products are for sale, they would fetch a much higher price in the market. The production of a small quantity of goods is done for goods that are expensive and are not easily substituted (Dembinski, 2002). Advancements in Computer Aided Manufacturing technology The success of a manufacturing enterprise in the future will largely rely on the efficiency of the technology it employs in its production process. The process that is currently used to design computer aided manufacturing processes is not properly outlined. There is a need to produce new environments for developing new CAM systems and application. Recent trends in computer aided manufacturing environments involve systems that are based on computer workstations or in a network of computers. Engineers and technicians working on different workstations and can share information through a common database. These trends in the manufacturing system are because of the following trends in the industry. An increase in the number of product reliability suits has led to a need for a more reliable system that will ensure products produced are more reliable. i. The customer has increased a desire for better quality products that are available for a cheap price. ii. The customer has also shown a desire to have a shorter delivery time. This necessitates for a faster CAM process. iii. The need to reduce the time gap between the design of a product and the manufacture. iv. The number and the variety of products have continued to increase. This has resulted in a decrease in the quantities of each of the various products. v. The continuing decrease in the percentage of the cost of direct labor as a part of the overall cost of a product has led to the development of systems that are capital intensive. vi. The implementation of Just-in-Time production method where goods are produced to meet demand and not in advance for a predetermined need. Current CAM processes and machines being designed have the capability of being flexible and produce as required by the market (Sundar, Selwyn & Elanchezhan, 2007). The current trends in the manufacturing process are aimed at: i. Increasing the production rate ii. Reducing the percentage of defective products iii. Improve on the delivery time. iv. Reduce the amount of work in process inventory. v. Reduce the overall cost of production. vi. Reduce the initial cost of installing the system. Notable trends in the manufacturing process include: i. Robotics The Robot Institute of America defines a robot as a reprogrammable multi-functional manipulator, which is designed to relocate parts, tools, and devices through variable programmed motions. Robots are used in the manufacturing process for moving materials in the factories. ii. Flexible manufacturing: Automation in traditional manufacturing processes had the disadvantage of being inflexible in terms of the output characteristics. Modern manufacturing processes are designed to allow flexibility in terms of the batch size and the overall number of products. The traditional automation process used the continuous flow process (Chaturvedi, 1998). Over the last four decades since the 1970’s, there has been an unprecedented growth in the use of computers to assist in tasks pertaining to design and production. The use of computer applications has developed beyond design and into the business functions. This is referred to as Computer Integrated Manufacturing (CIM). CIM was merely a concept in the 1970’s. However, due to rapid improvement in technology, it was realized and implemented. Modern manufacturing firms now view CIM as a necessity and they invest heavily in it (Venkateshwaran & Alavudeen, 2008). Another major trend in CAM systems is the use of hierarchical computer systems. For these systems, CNC computers have a direct control over the machines. The computers are connected together using satellites or other long distance networking media such as fiber optic. This system is flexible as information is suited to the individual needs of the clients without the need to abide to rigid reports. CAD and CAM systems are integrated and they share a common database. This system can also be built systematically, making the addition of changes or corrections easier (Haideri, 2008). Conclusion The manufacturing process is evolving and the manufacturing industry needs to adopt the latest technologies to improve productivity. The use of robots in factories to replace human labor reduces the amount of wages and risk allowances. Robots should be used in processes that pose a risk to human workers. The evolution of technology in the manufacturing industry is advantageous to the economy as a whole. Consumers enjoy cheaper products while manufacture benefits by reaping higher profits due to reduced cost of production. References ALAVUDEEN, A., & VENKATESHWARAN, N. (2008). Computer integrated manufacturing. New Delhi, Prentice-Hall of India. CHATURVEDI, P. (1998). Modern trends in manufacturing technology. Concept Pub. Co. ELANCHEZHAN, C., SUNDER SELWYN, S., & SHANMUGA SUNDAR, G. (2007). Computer aided manufacturing (CAM). New Delhi, Laxmi. HAIDERI, F. (2008). CAD/CAM and Automation. Nirali Prakashan, Prune. INTERNATIONAL CAMT CONFERENCE, & DEMBIŃSKI, B. (2002). Modern trends in manufacturing: first International CAMT Conference, Wroclaw, 7-8 February 2002. Wrocław, Oficyna Wydawnicza Politechniki Wrocławskiej. MCLEAN, C. Computer-Aided Manufacturing System Engineering. National Institute of Standards and Technology. RAO, P. N., TEWARI, N. K., & KUNDRA, T. K. (1993). Computer aided manufacturing. New Delhi, Tata McGraw-Hill. Read More