RFID USAGE IN RECONFIGURATION OF MANUFACTURING PROCESSES

Research by :

Farshad TavallaliniaSiavash Emami

A production control system is used to plan and control a series of manufacturing processes to maintain the required quality level and delivery schedule.

Most current production control systems include a centralized database for production information and production schedule information for relevant facilities, and these systems provide an optimal scheduling plan in a centralized way using this information.

An RFID-based control scheme for production control systems, one that solves these problems, has been created based on the concept of holon.

So, each component of a product as a holon has been considered , and this holonic component is controlled by the RFID tag attached to the component, efficiently works in the production control system.

Each RFID tag has the lifetime information necessary for the production written by the system, such asUniversal identification number (UID) to identify the attached component.Parts number.Production facility ID to be supplied for the component.Delivery deadline time.

Receives order information and makes initial production plans

Generates lifetime information of RFID tags and writes it into each RFID tag

Makes revised information based on order changes and sends it to the controllers of production facilities

R : RFID tag reader/writer T1 , T2 , T3 : RFID Tags

1) A large piece of cloth with a single RFID tag is colored in the dyeing process .

2) It is transported to the cutting process, where it is sliced into pieces and where an RFID tag is attached to each piece of cloth.

3) Wire props, each with one RFID tag and a piece of cloth with a matching RFID tag, are processed into the final umbrella product .

4) RFID tag readers/writers are attached to the front and rear of production facilities to read RFID tags attached to the components .

5) When each process is completed, the RFID tag reader/writer in the rear side updates the current status in the tag. If the order changes, the RFID tag reader/writer in the front side modifies the status in the tag to indicate a cancellation or increase or decrease in the number of products.

It can flexibly accept change in orders during ongoing productions without strict rescheduling.

The scheme is effective in reducing lead time and costs associated with production and that it is also effective in maintaining delivery schedules.

Concurrent Engineering is a work methodology based on the parallelization of tasks. It refers to an approach used in product development in which functions of design engineering , manufacturing engineering and other functions are integrated to reduce the elapsed time required to bring a new product to the market.

Integrating RFID technology with the concurrent manufacturing model can dramatically reduce response time to customer inputs.

TruckLet us imagine that a truck is to be assembled. The customer usually specifies the engine, possibly the transmission, the tires, body paint and cabin accessories like the stereo. Designers and customers would have the flexibility to change specifications midway through manufacturing with each part being RFID tagged. At any moment of time, the specifications written onto the tag could be modified and production could proceed normally. This would shorten response time because design and manufacturing periods would have overlaps. Moreover, designers and process engineers would be able to control the process changes using wireless signals to directly update the RFID tags, thus reducing paperwork and human interference and improving the efficiencies obtained through automation.

The computer-aided assembly line based on RFID will improve efficiency in many kinds:

By using RFID readers to read tag’s information, the amount and detailed information of parts can be rapidly collected and input into the computer. It can save lots of resources and time.

RFID readers are also fixed on the assembly line, the information of the parts which will be assembled on the assembly line could be read by the readers. So the mating arrangement can be checked and corrected by the computer. It can prevent the emergence of the wrong assembly.

Right now two car companies use RFID in their assembly line:

The BMW applies RFID to the assembly line, in order to produce massively the customer-making car. The BMW’s production is based on the style in which customs request is first. The customer can select his favourite colour, engine and tire style from the thousands of different choices, therefore, there are hundreds of different kinds of cars in the BMW’ s assembly line. Without a highly organized and complex control system it is very hard to complete the complicated task. In order to solve this problem, the BMW fix its assembly line with RFID, and they can use repeatedly tags with detail request of the car, there are readers/writers in every work spot. That can guarantee finishing the car assembly in each line without any mistake.

Track vehicles from final assembly to shipment and ensure accurate loading to rail, ship and truck.