Study on Flexible Manufacturing Systems

Introduction

Flexible Manufacturing System (FMS) is the currently trending production philosophy adopted by industries involved in the batch production of components. FMS is a concept supporting the Industry 4.0 revolution. The three levels of flexibility include basic flexibility, system flexibility, and aggregate flexibility. In recent times, FMS has been rapidly spreading across automotive industries in the segment of luxury car OEMs, owing to the diverse nature of variants developed by brand manufacturers. Industries are aiming at cost-cutting strategies to outcompete their competitors without compromising on quality and delivery, which creates the need for FMS.

Need for FMS

Currently, manufacturers are expected to produce high customization–high mix parts/ components with reduced lead times and low costs to sustain themselves in the competitive market, creating a requirement for FMS. The demand for high mix–low volume components from industries—medical, aerospace, automotive, etc.—require high flexibility in the production facility, which initiates the need for FMS. Majorly, the OEMs of many industries have planned the upgradation of automation levels in factories to ensure high productivity and better quality and reduce higher dependency on manual labor. There is a need for reduction in downtime during the setup of tools, dies, etc., thereby increasing efficient usage of machine time. Consequently, operation costs are expected to decrease relatively because the ability to adapt quickly to changes helps to reduce downtime and material wastages. A few FMS adopters have reportedly achieved production efficiency of 150 to 200 percent and a reduction of lead times by over 20 percent. Further, the need for agile production in industries such as medical, aerospace, etc., are extensively supported by FMS principles.

Impact of FMS on Productivity and Quality

The implementation of FMS has resulted in a positive impact on both productivity and quality. High quality is maintained by implementing FMS owing to factors such as increased accuracy, increased consistency, reduction in human error, etc. The increased automation/flexibility in implementing FMS has a direct impact on reduced production lead time, apparently resulting in significant product quality improvements and increased accuracy. For instance, in a metal cutting industry, a few operations require complex process flow designs, and the selection of the cutting tool is critical at different stages. FMS implementation supports the process planning team in choosing the right/ appropriate tool for the cutting operation in minimal time, thereby significantly reducing the process time, which apparently increases the productivity. The tool life plays a significant role in achieving a high-quality finished product during the metal cutting process. Tool life is continuously monitored by FMS and helps the operator avoid errors during the machining process, thereby improving product quality.

Challenges Involved in Implementing FMS

The planning phase is the most critical stage in implementing FMS and requires detailed designs and schedules. FMS implementation requires high capital investment because of which Tier II and III suppliers find it highly challenging. Typically, robots are installed with software programs, which are connected through servers to integrate and coordinate the activities with machine tools. Currently, one of the major constraints for many manufacturing industries is the infrastructural setup. The existing plant layout requires major alterations in machine tool arrangements to provide adequate space for installing robots, thereby setting up a hybrid layout that includes both process and product type plant layouts. Further, raw materials and the tool storage setup are important in deciding the plant layout and help in significantly reducing the loading/unloading process downtime.

Big Data analysis involves huge labor hours in collecting and feeding past data into computers and requires periodic updates. This helps the FMS take quick decisions in real-time scenarios without human intervention. Post FMS implementation, a major challenge could be the requirement of highly skilled employees for operating machinery/equipment, thereby leading to higher expenditure on their salaries. Preventive maintenance activity is expected to be conducted at regular intervals, which could involve higher annual maintenance costs. Considering the abovementioned challenges, FMS is implemented only in stages in an existing plant setup owing to the necessity of temporary production shutdowns during the installation period, ranging between two to four months based on the plant capacity. FMS implementation is slowly expanded to the entire factory setup based on the efficiency parameters of cost, quality, flexibility, and dependability.

FMS Applications

FMS is majorly implemented in applications wherein batch production of components/parts is involved and specifically in warehouse management that involves automated material handling, storage/retrieval systems, automated inspection, etc. FMS utilizes several CNC machining centers arranged in a particular pattern with robots installed around them. The integration of machines and material-handling robots is typically achieved using a software program such as Scada or PLC. In a particular case study of POLMAN T-100 vice casting components, the following results were achieved after implementing FMS when compared with the conventional method for producing 200 pairs of casting products:

• About 22 times faster production runs were achieved, thereby increasing the productivity.
• Material handling time increased to 5.14 times during the production cycle.
• Operator intervention decreased.

Market Trends

Automation in storage/retrieval systems using automated guided vehicles (AGVs) and robots is one of the key FMS trends. Big Data systems help take decisions based on real-time data, thereby supporting FMS. Currently, Internet of Things (IoT) has been implemented in companies like Amazon in their distribution/warehouse systems for easy and faster operational activities. IoT is used to communicate between machines that directly send instructions to AGVs immediately after the purchase order is picked up. Based on the product type, suitable AGVs are assigned to pick up the required product from its exact storage location and carry it to the packaging section without human intervention. IoT helps manage inventory stock product count and automatically sends an intimation to the purchase team for product restocking. Some of the major players involved in developing IoT technology are Vates, Eastern Peak, Oxagile, and PTC. Big Data with IoT is the current trend in many manufacturing industries for implementing FMS to achieve zero error with increased efficiency. Processes such as forging, machining, metal fabrication, and surface treatment are automated and interconnected by FMS implementation.

Conclusion

Flexible manufacturing is a significant technology in modern times for producing high-quality goods with increased operating efficiency. Implementing FMS could considerably reduce the human labor involved; however, the initial investment is high owing to the installation of robots/machines for automating manufacturing processes, material handling, etc. FMS majorly supports the concept of Industry 4.0, thereby upgrading industries to the next level of automation.