Reconfigurable Manufacturing System

A reconfigurable manufacturing system (RMS) is a system invented in 1998 that is designed for the outset of rapid change in its structure, as well as its hardware and software components, in order to quickly adjust its production capacity and functionality within a part family in response to sudden market changes or intrinsic system change. A reconfigurable machine can have its features and parts machined.

History

The RMS, as well as one of its components—the reconfigurable machine tool (RMT)—were invented in 1998 in the Engineering Research Center for Reconfigurable Manufacturing Systems (ERC/RMS) at the University of Michigan College of Engineering.Koren Y. and Kota, S.: Reconfigurable Machine Tool. US patent ; issue date: 8/31/1999.Koren, Y. and Ulsoy, G,: Reconfigurable Manufacturing System Having a Method for Changing its Production Capacity. US patent # 6,349,237; issue date: 2/19/2002. The term ''reconfigurability'' in manufacturing was likely coined by Kusiak and Lee.

From 1996 to 2007, Yoram Koren received an NSF grant of $32.5million to develop the RMS science base and its software and hardware tools.NSF Grant: Engineering Research Center for Reconfigurable Machining Systems
/ref> RMS technology is based on an approach that consists of key elements, the compilation of which is called the RMS science base.

System operations

The system is composed of stages: 10, 20, 30, etc. Each stage consists of identical machines, such as CNC milling machines. The system produces one product. The manufactured product moves on the horizontal conveyor. Then Gantry-10 grips the product and brings it to one of CNC-10. When CNC-10 finishes the processing, Gantry-10 moves it back to the conveyor. The conveyor moves the product to Gantry-20, which grips the product and loads it on the RMT-20, and so on. Inspection machines are placed at several stages and at the end of the manufacturing system.

The product may move during its production in many production paths. In practice, there are small variations in the precision of identical machines, which create accumulated errors in the manufactured product; each path has its own "stream-of-variations" (a term coined by Y. Koren).Jianjun Shi, J. Stream of Variation Modeling and Analysis for Multistage Manufacturing Processes. CRC Press, Taylor & Francis Group, 2006. .Hu,, S. J. and Koren Y.: Stream of Variation Theory for Automotive Body Assembly. Annals of the CIRP, Vol. 46/1, pp.1–6. 1997.

Characteristics

Ideal reconfigurable manufacturing systems, according to professor Yoram Koren in 1995, possess six characteristics: modularity, integrability, customized flexibility, scalability, convertibility, and diagnosability.Landers, R., Min, B.K., and Koren, Y.: Reconfigurable Machine Tools. CIRP Annals, Vol. 49, No. 1, pp. 269–274, July 2001. Characteristics for its components are: reconfigurable machines, controllers, and system control software. An RMS does not necessarily have all of the characteristics. These principles are called Koren's RMS principles. Supposedly, the more of these principles applicable to a given manufacturing system, the more reconfigurable that system is. The RMS principles are:

The components of RMS are CNC machines, reconfigurable tools, reconfigurable inspection machines,Koren, Y. and Katz, R.: Reconfigurable Apparatus for Inspection During a Manufacturing Process. US patent # 6,567,162 Issue date: 5/20/03. and material transport systems (such as gantries and conveyors) that connect the machines to form the system. Different arrangements and configurations of these machines will affect the system's productivity.Koren, Y., Hu J., and Weber T.: Impact of Manufacturing System Configuration on Performance. CIRP Annals, Vol. 1, pp. 689–698, August 1998. A collection of mathematical tools, which are defined as the RMS science base, may be used to maximize system productivity with the smallest possible number of machines.

See also

* Modular design

References

{{Reflist

Manufacturing
Modular design