WireManager for Windows NT

Executive Summary

Introduction :

WireManager for Windows NT has been developed for Volkswagen Electrical Systems Inc. which is settled in Cerkezköy/Turkiye in 1995. The system has been working since April 1996 and it aims the automation of the orders in the wire processing (cable cutting) machines park of the factory. WireManager has provided an % 10 increase in efficiency for Volkswagen Electrical Systems Inc.

• WireServer (WireServer Program)
• WireMonitor (Supervisor Program)
• WireOperator (Operator Program)

The system is also connected to the AS400. With this connection, the new (raw) orders are charged into the system automatically.

• Setup time optimization : The setup times between the orders are being optimized by a heuristic developed for the Traveling Salesman Problem. In this way, the setup times between the orders decrease and the capacity of the machines increases. Only by the optimization of the orders, it is possible to have a %3-5 increase in the efficiency.
• Capacity calculation : The capacity of every machine  is defined and the orders are charged according to this calculation. The order processing times are being determined for every machine they will be charged to. The efficiency of every machine can be defined by the Supervisor.
• Dual server management : There exists two servers in the system. When the master WireServer WireServer1 fails, the slave WireServer WireServer2 takes the system over itself without any need to a Supervisor intervention. When the master WireServer comes to operation, the slave WireServer gives the control of the system back to the master server.
• Graphical visualization : The orders and the machines can be monitored graphically in the WireMonitor. The orders are illustrated as boxes along the time axis, making it easy to foresee when and at which machine the orders are scheduled to be processed. The status of the machines and orders are displayed in color to attract the attention of the Supervisor to certain situations.
• Reschedule of the orders : It is possible to reschedule the orders one by one or in blocks. With the block rescheduling feature, it is possible to reschedule the orders in seconds where otherwise it would take several hours.
• Host connection : The order information is taken from the host (AS400) and the production data are transferred back to the host automatically.
• Parametric structure : WireManager has a parametric structure. The system has been designed to adopt to changing demands by having the Supervisor change the value of the most of the information in the system. For example, a new machine, machine group, suspend code can be added easily and the setup parameters can be defined according to the different machine groups in the system etc.
• Substitutable machine groups : In WireManager, while charging the orders to the machine groups, the substitution of the groups are being taken into consideration. First the orders of the groups that can not be substituted by other machine groups are charged, and then the orders of the groups that can substitute the other groups are charged. At last, the remaining orders of the substitutable groups are charged to the groups that can substitute these groups.
• Calculation of Order Duration : The duration (processing time) of any charged order is determined by the formula which is a function of the order parameters and the machine specifications. The results of this formula are very close to the real operation processing times. This feature provides accuracy in capacity planning.
• Querying the Database using SQL : Supervisors that have SQL experience can retrieve information from the past and current production data using the SQL features of the WireMonitor.
• Graphical Operator Screen: The operators working on the cable cutting machines can see the details of the orders they are processing and can easily consider the preparations they have to make for the next order by a graphical user interface provided to them by the operator program. The special situations which they have to be careful about (ex. special cable) are indicated with flashing visual components so that they are prevented from doing mistakes.
• Search for an Order : In WireMonitor, an order may be searched according to its order number or its part number. The detailed information about this order may be easily achieved by this way.
• Work Load : The Supervisor can follow the work load of all WireOperators or of a single WireOperator both graphically and numerically (in minutes). 
• Barcode Label : After the order is processed, a barcode label is printed at the amount of box count.
• Archive Database : The production data for processed orders are archived in an archive database. This makes the  size of the current database smaller and provides an increase in the performance.

   

Order Processes :

As mentioned above orders are received by a file from AS400. The flow chart below shows the stages after this file is received.

Import : Orders are transferred into a temporary table in the WireServer database.

Examining Orders : The orders are supposed to suit some predefined conditions. The orders with meaningless information, such as missing order number or incompatible part number. The list containing the information of such bad orders are sent both to the supervisor and AS400.

Optimization : Orders in each machine group are scheduled according to the minimum setup time. For each machine group an order list is being prepared.

Calculating Capacity : The machine where the order will be processed is determined according to the working plan which is presented by the Supervisor. This working plan consists of shifts and the supervisor determines when any machine will work for production. The result of this process is  informed to the Supervisor. This information includes how much capacity a machine group still has or how many orders are not charged to that machine group because of lack of capacity. Supervisor can then change the working plan and make the WireServer recalculate the capacity again.

Charging Orders : After the machines where the orders will be produced are determined then the Orders are charged to the WireOperators over the network.

Gathering Production Information : While operators process orders, production data is sent to the WireServer by the WireOperator program. This process occurs off-line which means that when the WireServer program is not running the production data are kept in the WireOperator database and when the WireServer program starts running they are sent.

Rescheduling : The supervisor can change the rank of the order on any WireOperator or he can change the machine the order will be processed. This work is called Rescheduling. Rescheduling can be done both for a single order or for a group of orders. The reschedule operation which is very complex, makes it necessary to re-calculate the setup time and the duration of the order being rescheduled, and the orders that are affected by the reschedule of the order in question. Otherwise the system goes far away from the realism. This operation is completed in several seconds where it would take around 45 minutes to do it manually.

Sending the production information to AS400 : The production data gathered from the system is sent to the host very 15 minutes (or other) within a text file.