2.1.2. Stage of Verifying the Capacity and Operational Availability (Verification)
In the framework of the stage of verifying the capacity and operational availability we gradually carry out a two-stage verification of all products from the quantity
P. The first part is the conformity verification between the product operations and operations that can be realised by the manufacturing system equipment as it shown Algorithm 1. The verification requires calculating the total number of the common elements
. After determining the quantity of the common elements it is necessary to calculate the conformity for a particular product
The conformity result must not be lower than 100% because the manufacturing system can manufacture only such a product for which it is able to ensure processing all its operations. In the case the percentage conformity is lower, an agreement with the customer is necessary. The next step of the verification stage is to determine the critical ratio (CR) for the product
kn. The critical ratio (CR) is a rule used in priority sequencing of work waiting for processing at a work centre. If this rule is used for sequencing, the job with the lowest CR is scheduled first. A CR less than 1 indicates that the job will be late, and a CR greater than 1 indicates that the job can be completed ahead of the due date if no unexpected delay occurs. The critical ratio in this case serves as an identifier of the resulting manufacturing time for individual products. Before calculating the critical ratio we have to calculate the values of the manufacturing volume
, increased by 0% of the technologically inevitable scrap. The next step is to calculate the value of the real time necessary for manufacturing every product
. Through the value of the time proportion defined by the customer and the time that is really necessary for manufacturing the product we can determine the resulting production time
. If the really necessary manufacturing time is longer than the time defined by the customer for the transfer, we will shorten the resulting time for the product to be produced. If the real time for manufacturing the product is shorter than the time defined by the customer, the resulting time
is given a lower value. The last possibility is—if the result of the critical ratio is 1, then the resulting time
equal with both times [
4].
Algorithm 1 Algorithm of input data stages and verifying the capacity and operational availability |
01: stage Input Data() |
02: generate value (, , , , , , , ) |
03: call Verification(, , , , , , , ) |
04: stage Verification(, , , , , , , ) |
05: |
06: |
07: if then |
08: call ) |
09: else |
10: |
11: |
12: |
13: if then |
14: |
15: elseif then |
16: |
17: else |
18: |
19: end if |
20: |
21: |
22: if then |
23: call ) |
24: elseif then |
25: call ) |
26: else |
27: call Verification in Time) |
28: end if |
28: end if |
The last part of the verification stage is to determine the necessary capacities of the equipment for the products
. The calculated sum of the theoretical value of the necessary number of devices
is subsequently compared with the value of the total number of the system’s devices
ZQ. By comparing the values, we will obtain a preliminary overview about the possibilities of manufacturing the products. If the sum of the equipment for each product is not equal with the total defined number of the workplaces of the system, so the system has not a sufficient amount of devices for the time
. If there is equality
of the resulting time and the time defined by the customer of transferring the product, it is inevitable to consult the problem with the customer. The stage Customer replaces the decision-making of a real customer in the algorithm. However, if the time
defined by the customer is higher, there is a reserve for manufacturing the product
and we do not contact the customer. If the value calculated does not exceed the amount of the devices in the system, the calculation continues for the verification stage concerning the product manufacturability in time [
11].
2.1.3. Verification of Products’ Manufacturability in Time
After verifying the products in the previous stage, it is necessary to specify the next decision-making criterion—the manufacturability the process is shown in Algorithm 2. This criterion will enable to decide about the manufacturing possibilities of the products and creation of the product family during individual iterations. This criterion is the minimal time of making a product at a maximal utilisation of the available system resources . If we are able to define this minimal time, we can guarantee the possibility of manufacturing a particular product in the next iteration. The basic assumption for determining the minimal time is the validity of the algorithm condition which says that the number of the allocated resources has to be lower or equal to the number of all available resources of the system ZQ.
The sequence of determining the minimal time depicted in the algorithm begins with calculating the total number of the machines .
The basis for determining the number of machines is the value
x that is increased on the interval
by the lowest possible selected value of the increment
.
Algorithm 2 Algorithm of product verifiability in time |
01: stage Verification in Time() |
02: |
03: ) |
04: if then |
05: |
06: |
07: |
08: call Priority of Products(, , , ) |
09: else |
10: |
11: call Verification in Time() |
12: end if |
The value of the number of the machines
is subsequently verified in the assignment stage. The essence of this stage consists in assigning the necessary operations to particular existing machines of the system, namely in dependence on the need of the amount of the equipment and operation type. After each assignment of the calculated number of machines the condition introduced in the algorithm is verified. The condition says that in the case if the number of the assigned machines
is not lower than the amount of the calculated devices, it will be necessary to increase the increment value
x by 1. This process repeats until the condition is fulfilled. After fulfilling the condition it is necessary to calculate the last value
x in the case of which all devices could be assigned. We will calculate it by subtracting the value 1 from
x. The determined value
x subsequently is equal to the minimal time when the available resources of the system
are maximally utilised [
4,
5,
6,
7,
8,
9,
10,
11,
12].
2.1.4. Determining the Product Priority
The Algorithm 3. shows stage which is the basic part for creating the product family
because the calculation of the priorities of the products will determine their overall sequence for the assignment Ω. The products will thus be assigned to the product family directly on the basis of their availability therefore we chose two determining criteria for determining the product priority. The first criterion is the assessment of the products based on the calculated times
, when the products with lower processing time have the priority. This criterion is based on the SPT rule (short processing time). For acquiring the quantity of the SPT we will arrange the values of the times
from the lowest up to the highest ones. The second criterion is the product similarity based on the types of the operations that are defined by their technology or assembly. The basis for determining the priority of this criterion is the utilisation of two stages—the cluster analysis (CA) and the algorithm longest common subsequence (LCS). The result of these stages is the sequence quantity
CA [
13,
14].
Algorithm 3 Algorithm for determining the product priority |
01: stage Priority of Products(, , , ) |
02: call ) |
03: call ) |
04: |
05: |
06: |
07: |
08: |
09: |
10: |
11: |
12: |
13: call Family Time, , ) |
Based on the defined quantities SPT and CA, it is then possible to determine the sequence of their values
and
based on the following logic:
The input parameters from previous stages enter again the stage of determining the product priority, however, the values of the defined weights
are important. They define which of the criteria will be more important for defining the overall sequence Ω. The determination of the previous values of individual maximal weights is dependent, in this case, on the following equation:
Through defining the real sequence from the point of view of the time criteria SPT and similarity CA we can unite the values of their weights and the result will be the overall product sequence Ω. However, first of all it is necessary to calculate the unit index of the weight for both criteria. The final phase of determining the sequence Ω for creating the product family is the calculation of the values of the weights for both criteria and also for the individual products kn. These values of both criteria are subsequently added up for each product independently and the resulting values are ordered from the highest to the lowest one. By ordering the results we achieve finally the total sequence Ω.
2.1.5. Creating the Product Family and the Stage of the Resource Availability
The main part of the designed methodology is the stage of creating the product family and the stage of the resource availability. As mentioned in the previous chapter, these stages are created by several partial steps. These steps can be united into three main parts that will be described in the next sections. The first part is the creation of a cluster of products α and defining the production volume for the defined operations of the manufacturing configuration. The second part is the calculation of the necessary quantity of the machines for the designed configuration and its subsequent verification through the simulation software. The third part specifies the necessary backup of the equipment for the verified configuration containing two or more products. The products are assigned gradually in dependence on the designed total sequence of assignment Ω and the decision about the amount of the non-assigned equipment of the system. The last step is the verification of the configuration in the assignment stage that will determine the volume of the assigned machines for the products of the family and will send the values to the decision-making stage.
Creating Product Family—Part 1
The clustering of the products into a product family is the basic part of the designed methodology assuming their mutual similarity from the point of view of the operation types (production technology) and this process show Algorithm 4. The creation of the family requires not only finding the same operations for manufacturing the products, it is also necessary to determine the longest mutual sequence of the same operations. This operation sequence is defined by the stage LCS [
15]. The algorithm of the LCS stage will find and determine this operation sequence of a couple of products, in the case of an already created cluster of two or more products it creates a sequence between the couple product—the created cluster α. This mutual sequence of the same operations can be written as the matrix
that is the main entrance parameter for the next parts of the algorithm.
Algorithm 4 Creating the Product Family and the Resource Availability—Part 1 |
01: stage Family Time(, , ) |
02: ) |
03: rename elements of matrix |
04: |
05: |
06: |
07: to |
08: then |
09: |
10: |
11: |
12: |
13: |
14: call Family Sources() |
15: else |
16: then |
17: then |
18: |
19: |
20: |
21: |
22: |
23: else |
24: |
25: |
26: |
27: end if |
28: else |
29: then |
30: |
31: |
32: |
33: else |
34: |
35: |
36: |
37: end if |
38: end if |
39: end if |
40: next k |
Several products or an already existing cluster enter the connection process during creating a cluster. Their operations are generally defined by the matrices for the products and the matrix for the cluster. However, a general designation is to be created for the connection process, i.e., for the product entering the cluster and a product or a set of products fulfilling the conditions of assigning the resources. The same process of renaming is necessary for the matrix Tkn expressing the operation times for the product and also for the matrix of operation times of the created cluster α. Owing to the renamed matrix elements it is possible to clarify the principle of the clustering algorithm function in a simpler way. The first step defines the condition comparing the operation of the entering product with the matrix element of the common elements . If the operations are the same, another condition continues and compares again the matrix element with the element of the matrix of common elements . If all three elements are identical the operation is assigned to the new final matrix and it is necessary to add up the operation time and of these identical operations.
However, if the element is not identical with the element , it is necessary to verify the variable k with the number of elements of the matrix designated as If there are no common elements any more, only the operations from the second matrix are assigned, if not all common elements are assigned, the elements from are assigned to the matrix . The whole assignment cycle takes place until the variable equals the value of the maximal number of the operations from the products selected.
The last part of the described algorithm is the calculation of the production volume for the individual production levels
that will produce certain types of operations given by the matrix
. Every manufacturing level is thus determined for an independent type of operation and a various quantity of the products will be processed in its framework. Therefore from the capacity point of view a particular manufacturing volume has to be calculated for each level. Also the durations
differ from product to product therefore it is necessary to determine the common time
during which the ratio of the product quantity of the product family is produced. The common time of the product family is actually a minimal time from the quantity of all manufacturing times of the products that are assigned to the product family. After the time
is over, the production of the product belonging to these values will be finished and the system configuration can be re-configurated again for another product family [
16].
The calculation of the manufacturing volume for individual operational levels will be preceded by a calculation of the manufacturing volume for the product per determined time period regarding to the original time However, these manufacturing volumes are determined for the product, therefore it is necessary to calculate the manufacturing volume for each operational level independently depending on the types of the products and operations that are assigned to the manufacturing levels.
In the next part of the algorithm we will design the manufacturing configuration compared with the simulation model and the criterion of this model will require fulfilling the conditions for processing the given manufacturing volume. Because of this condition it is necessary to calculate the whole assigned manufacturing volume by the sum of all re-calculated manufacturing volumes for the products. This volume will be a comparison criterion for fulfilling the conditions of the configuration being tested.
Creating the Product Family—Part 2
The basis for the production layout design is to determine the necessary amount of equipment for a particular operation of the given manufacturing/operational level and Algorithm 5. show this process. The number of devices of the manufacturing level is dependent on the calculated takt and rhythm of the whole line. The takt and rhythm of production are the values giving the average time interval between the transfer of two parts that follow each other. However, the rhythm of line operation takes into account the production time reduced by the total time of the losses due to the technical or organisational causes. For the given calculation we will not assume the time of losses due to the organisation breaks and therefore it is not included in the algorithm calculation. The failure of the equipment due to technical causes is not the subject of this calculation but it is taken into consideration in the modules of the line backups. The last factor that can be defined as a loss of time is the time of the line reconfiguration. However, this time does not affect the calculation of the capacities and there we take it into account even for determining the total iteration time.
The calculated number of devices need not be able to process the necessary products per the time defined and therefore the designed configuration is to be verified. For the verification purposes we created a correction coefficient that reduces the value of the line rhythm and the number of devices is growing in this way. The rhythm of the line operation is calculated on the basis of an adapted formula of the line rhythm .
Through the determined rhythm of the line operation it is possible to calculate the synchronisation coefficient for every operation. But the synchronisation coefficient formula is to be adapted. As a matter of fact, several products of the product family pass through the manufacturing level. The total time calculated for the product family makes is thus to be divided by the number of these products passing through the given operation .
By rounding up the coefficient value we will obtain an integral number defining the total amount of the necessary workplaces for the given operation .
The next part of calculating the algorithm is the calculation of the sum of the total number of the line workplaces
. This value will be an assessing criterion of feasibility for the configuration of the product family cluster α in the next module [
17,
18].
Algorithm 5 Creating the Product Family and the Resource Availability—Part 2 |
01: stage Family Sources(, ) |
02: do while |
03: |
04: |
05: |
06: |
07: |
08: |
09: |
10: call Simulation Submodule() |
11: |
12: loop |
13: call Family Backup(, , , , ) |
Besides the calculation of the total number of the workplaces we can also calculate the time utilisation of the operational level and assess the utilisation of the workplace in the future. The results of the utilisation can be also compared with the results of the sub-model simulation stage.
As already mentioned, the designed configuration is to be verified in the next step, namely in the simulation stage. The simulation was realised through the simulation software Tecnomatix Plan Simulation and a parametric simulation model was created for the verification purposes. However, especially the results concerning the quantity of the processed products an important aspect of the realised simulation.
Based on the precious part we determined the total sum of all assigned manufacturing volumes for the individual products ; this value will be compared with the value of all processed products achieved by simulation. If this condition is valid, the manufacturing configuration with the calculated amount of the devices is suitable and enables to manufacture the given production volume.
If this condition is not valid, it is necessary to utilise the described correction coefficient that will be cumulatively increased always when the condition about the increment value is not fulfilled. The increment value was stated at the value of based on several experimental calculations. Owing to simulation we calculated and verified the configuration up to defining the configuration that is capable to process the given production volume during the defined time .
Creating the Product Family—Part 3
The calculation of the backup for the machines is the last stage of the algorithm of creating the product family shown in Algorithm 6. The calculation of the equipment backups is based on the data about the failure rate occurring during the production of the previous product family. If a failure developed in the set of equipment in the previous iteration there is a higher probability that this failure will repeat and therefore it is necessary to create reserves in the form of a backup machine. In general we can differentiate two types of the machine backup—the cold and warm backup. In the case of the cold backup the equipment is inactive when no failure occurs in the line, however, when a failure develops that device is put into operation. The equipment cold backup needs a certain run-up time designated as
. Compared with cold backup the warm backup in an uninterrupted operation and no run-up time is necessary, however, the possible failures of the warm back-up can be a problem.
Algorithm 6 Creating the Product Family and the Resource Availability—Part 3 |
01: stage Family Backup(, , , , ) |
02: |
03: |
04: |
05: |
06: |
07: |
08: |
09: |
10: |
11: choose Device with |
12: |
13: |
14: |
15: |
16: |
17: |
18: |
19: |
20: |
21: |
22: if then |
23: determine |
24: else |
25: determine |
26: end if |
27: = call ) |
28: call , , , , Ω) |
The backup equipment should possess substitutability especially for the operation level. The highest failure rate occurred in the previous iteration. The most suitable variant is a device providing a high variability level when a high failure rate exists at several workplaces. In the next parts we will aim at determining the backup of the equipment for a particular operational level regardless of the variability rate of the backup device.
The calculation of the equipment backup is defined by several input parameters, they are mutually derivable and therefore they need not be unconditionally given. The basic input data is in this case the mean time between the failures and the mean time between repairs for a particular machine that were determined from the previous iteration.
As already mentioned in the previous section, the data is determined independently because of the reconfiguration after each iteration for every equipment. In the case of a newly formed product family the equipment can belong to a different operational level and in this way a change of the total value of the levels’ failure rate for a new line configuration develops. That is why it is important to calculate an average value of the given data of particular devices for the given operational level i. The average value of each parameter is calculated as a share of the total number of the equipment at the given level that was assigned by the stage of assignment sub-model.
Subsequently we can define the utilisation coefficient
out of these average values for each operational level
i. As it is depicted in the previous algorithm, the next step is to define the minimal value of the utilisation coefficient from all calculated coefficients. The lowest value of the utilisation coefficient determines the devices and operational level with the highest failure rate during creating the previous iterations. The machines realising just this operation will be backed up by the same backup device [
19].
The final configuration design also requires determining the type of the backup and therefore in the next step we will calculate the coefficient of the warm and cold backup. The calculated cold backup coefficient does not include the necessary runup time and therefore it is necessary to re-calculate the coefficient with the stated value of .
The majority of the devices needs a short runup time defined by the value that is not part of the calculation of the utilisation coefficient for the cold backup. If we assume that is part of every runup when a failure occurs it is possible to say that it is a coefficient of the equipment failures and the defined runup time. This product can be deducted from the total operational time of the equipment operation and the total time —the result will be the value of the operation of the backup equipment. Based on the assumed operation times and the inactivity we can calculate the assumed coefficient of the backup utilisation with the defined runup time.
If we calculate the utilisation coefficient of the backup device
with the defined run-up time and this value will be added to the original utilisation coefficient
of the operation level
i we will obtain a value that is distorted by the missing failure rate of the backup equipment. In the case of utilising the cold backup
we can assume that this value contains the failure rate of the operational level devices as well as the failure rate of the backup equipment. However, the value calculated does not involve the value of the given delay; we can say that the rest of the utilisation coefficient value up to 100% is the value of the missing failure rate. This rest is to be deducted from the sum of the coefficients of the backup device and the coefficient of the operational level. In this way we will obtain the real value of the utilisation coefficient of the cold backup with the given run-up time for the defined operational level. This stage is depicted in
Figure 2.
The last step is to assess the condition that compares the calculated cold and warm backup coefficients. In both cases it is necessary to reserve the devices for the system, however, the difference lies in the method of utilising the backup device during manufacturing the product family. In case the cold backup coefficient is higher, the equipment backed up by the cold backup principle will be utilised. In an opposite case the principle of the backup device through the warm backup is chosen [
20].
2.1.6. Final Configuration of the Product Family
The product family created by the previous stages can contain one or more products depending on fulfilling the criteria included in the next stage of the final configuration the process show Algorithm 7. This stage fulfils several functions. The check of the conditions verifying the product family manufacturability and the assessment of the times for transferring products for the next iteration belong to the most important ones. The stage algorithm can be divided into two basic parts—in the first one we carry out the verification of the designed product family.
Several values of the parameters enabling to assess the possibility of manufacturing the family products were acquired from the previous stages. The first parameter is the number of the necessary devices
for the designed product family involving one or several products. The number of the assigned machines
out of the total capacity of the necessary devices of the configurations is the next value. The value of the total number of the manufacturing system machines
ZQ is also necessary for the evaluation. The first step of the verification is the assessment of the condition evaluating the possibility of assigning the available devices to all required machines.
where symbol ? represents the way of concrete output of decision block in the algorithm. This representation was used because many decision blocks provide two and more possible results. Not only two as for “<” or “>”.
In the case of this condition only two situations can arise. The first situation will develop if the number of the assigned equipment of the system equals with all devices. The other situation develops if it is not possible to assign all machines that are required, and the designed product family is unrealisable for the given iteration. In the case the product family contains two or more products, it is necessary for the last assigned product given by the sequence to be replaced by another one in a defined sequence. This can be realised if the product given by the sequence that has not been assigned to a product family in the current iteration still exists.
If the values of the number of the assigned and required devices equal the availability of the system equipment will be verified. The second condition compares the amount of the equipment required by the designed product family with the total number of the devices that are available in the manufacturing system. In this condition only two possible situation develop again due to the fact that a case in the framework of which the number if the required machines is higher than the total number of the devices of the system logically cannot develop (regarding to the previous condition).
However, in the case when the number of the equipment assigned to the family
is lower than the total amount of the devices in the system the product family can be assigned another product given by the sequence
. The next step is then repeated testing the condition of the product family with the assigned product. The assignment of a new product is possible only in the case if there is still a product that was not assigned to a product family during the current iteration.
During a gradual verification of all assigned products several variants of the product families are continuously created. Out of these variants of the product families just the variant fulfilling both conditions is chosen. In this way are verified all products and their selection is determined by the condition of the operation similarity and the total processing time.
Another part of the algorithm is the assessment of the production feasibility that is not assigned to the current iteration. However, it is necessary to define the total processing time of the family before this verification and it is also necessary to define the input parameters that are defined in the next sections.
The designed product family is always created as a temporary configuration for a group of products whose duration is defined by the minimal processing time of the product of the family
. During this time period only the product with a minimal selected time
will be completed—the time
. The other products of the family will be manufactured only in this time period (duration). The completion of the unfinished products of the family and other non-assigned products will continue in the next iteration and thus in the reconfiguration of the system. The reconfiguration of the manufacturing line system is not part of the times of processing the products therefore it is necessary to take it into account by the iteration time. The time that will be necessary for the process of changing the configuration system
is added to the total production time. The next time affecting the total time of processing a product family is the simulation time
during which the production of all assigned
in the simulation is realised. The simulation time need not equal the given time
, therefore a simple condition for determining the total production time of the product family
taking the reconfiguration time into account can be defined.
The assessment of the product not assigned to a product family is the last part of the algorithm. Two main conditions—the comparison of the total production time of the family products
with the final time necessary for transferring the product
and the residual time
by which the manufacturing process can be reduced.
Algorithm 7 Creating the final configuration of the product family |
01: stage , , , , Ω) |
03: if then |
04: if then |
04: replace |
04: call , , , , Ω) |
04: else |
01: call , ,, ) |
05: end if |
04: else |
04: if then |
04: if then |
04: assign |
04: call , , , , Ω) |
04: else |
01: call , ,, ) |
05: end if |
04: else |
01: call , ,, ) |
05: end if |
05: end if |
01: stage , ,, ) |
03: if then |
03: |
04: else |
03: |
05: end if |
05: if then |
05: if then |
05: call Customer() |
05: else |
05: if then |
05: call ) |
05: else |
05: load for next iteration |
05: end if |
05: end if |
05: else |
05: call , ,) |
05: end if |
01: stage ) |
05: if then |
05: |
05: load for next iteration |
05: call , ,, ) |
05: else |
05: remove |
05: call , ,, ) |
05: end if |
In the case that all products were assigned to the product family, it is possible to continue the further stage and the next criteria will not be verified. However, the residual products are verified on the basis of the first condition that says that if the time given by the customer is shorter than the time of the iteration an agreement with the customer is necessary. The products that possess the time that is higher than the product family pass to the next condition that compares the iteration time with the residual production time . The residual time is a time by which it is possible to shorten the manufacturing process of the product for the next iteration. The verified product after shortening by this value will still have enough resources and can be produced during the original time . After exceeding this boundary a time shorter or the same as the minimal production time with a maximal utilisation of the resources remains for manufacturing. The product thus cannot be manufactured because unfinished products that will be processed in the next iteration remain in the product family. Similarly as it was in the previous case, an agreement with the customer is necessary. Only in the case of an inequality of the customer need not be contacted. If there is no reserve production time, the customer will decide about the prolongation of the time necessary for manufacturing a product or rejecting the production. In the case of prolongation the processing time will be increased by the value of the time iteration and the original time necessary for processing the product.
If the customer rejects the change of conditions, the product cannot be manufactured and it has to be removed from the assigned data. The assessment of the customer’s requirement is, owing to the method described, a rapid process and in this way the customer receives the feedback immediately after entering the product order. It is also possible to test the development of the iterations for the actually assigned products and the customers are informed in advance about the possibility of manufacturing their products with the actual time of transfer and requirement adaptations and to predict the various states of the future iterations.
2.1.7. Manufacturing Line
After verifying all criteria of the previous stage the created product family continues with the stage manufacturing line Algorithm 8. The main part of this stage should be a complex simulation that will take into consideration the equipment failure rate, possible fluctuations during iterations and their influence on manufacturing the products. The possibility of determining a suitable sequence of processing the products of the product family that could significantly contribute to further optimisation of the designed line should be part of the stage. The simulation could be also utilised for predicting the future states and on the basis of the historical data about the manufactured products also the iteration for the potential products the customers can order could be simulated. The selection of the optimal solution suitable for the current conditions would be realised on the basis of criteria defined in advance. However, the stage system optimisation is not thoroughly described because it part of the research in the future.
The next stage involved in the algorithm is the creation of the dynamic layout and already the name shows the overall concept of the methodology designed for the reconfigurable manufacturing and assembly lines. This methodology of designing the lines creates a configuration limited on a certain time interval—after the time interval is over the layout is modified. The problem of the line adaptability can be solved by two concepts. The dynamically reconfigurable system is the first concept. This system is able to arrange particular parts of the line according to the required needs; however, these parts have to of a modular character. The second concept is a statically reconfigurable system reaching the change through re-planning the material flow.
These stages and the solution of the RMS system is not part of the mathematical solution and their description serves only for specifying the given stage. The purpose of these stages is to define the state of the real or simulated manufacturing system after completing a particular product family during the time
through the output variables. The values of these variables subsequently define if new products were ordered or there is a change of the given orders of the products. The conditions of the algorithm based on the output variables will assess whether the stage will be completed or we will return to the initial stages of the algorithm and the whole process will repeat with new data. The stage is completed only in the case if there are no products that are to be processed any more.
Algorithm 8 Manufacture Line Reconfiguration |
01: stage , ,) |
02: call, ,) |
03: call, ,) |
04: if then |
05: else |
06: if then |
07: call Verification(, , , , , , , ) |
08: else |
09: call Verification in Time() |
10: end if |
11: end if |