COMPUTER-IMPLEMENTED METHOD FOR PROCESSING A PLURALITY OF PROCESS VARIABLES OF A PRODUCTION CELL

Abstract

A computer-implemented method using a processing unit and including providing to or determining by the processing unit a totality of process variables which is available for processing for the plurality of actuators and/or sensors of a subunit, using the processing unit to determine a subset of process variables out of the totality of process variables processing, during production of a production lot, those process variables which belong to the determined subset of process variables for those process variables which do not belong to any of the determined subset of process variables, and processing a selected number of process variables. In addition, a production cell has a processing unit configured to carry out the computer-implemented method, and computer program is provided to implement such a method.

Claims

1. A computer-implemented method for processing a plurality of process variables of a production cell which comprises at least one shaping machine as a subunit of the production cell, the method using at least one processing unit and comprising: a. for at least one subunit of the production cell, the at least one subunit having a plurality of actuators and/or sensors, providing to or determining by at least one processing unit a totality of process variables which is available for processing b. using at least one processing unit to determine at least one subset of process variables out of the totality of process variables c. processing, preferably during production of a production lot, those process variables which belong to the determined at least one subset of process variables d. for those process variables which do not belong to any of the determined at least one subset of process variables, processing a selected number of process variables.

2. The computer-implemented method according to claim 1, wherein the production cell comprises, in addition to the at least one shaping machine, at least one further subunit in the form of at least one of the following: at least one other shaping machine at least one mold mounted on the at least one shaping machine at least one handling device at least one periphery device, preferably: temperature control device, material dryer, material feeder, media manifold, dosing unit, mixing device, quality control device infrastructure for the production cell.

3. The computer-implemented method according to claim 1, wherein in step (b) the at least one processing unit determines at least one of the at least one subset of process variables based on at least one of the following: configuration of the at least one subunit of the production cell history of the at least one subunit of the production cell configuration and/or history of a plurality of other production cells physical or logical dependencies of values, preferably key figures, derived from at least one process variable and/or signals to be provided by the method to an operator operator input.

4. The computer-implemented method according to claim 1, wherein in step (c) processing process variables, which belong to the determined at least one subset of process variables and/or, in step (d), which belong to the selected number of process variables, comprises: capturing or measuring process variables in form of measurement values, and/or calculating values or properties of process variables over time, preferably key figures, derived from at least one process variable, and/or generating signals to be provided by the method to an operator, and/or executing data analysis, preferably inspecting, transforming, modeling, interpreting, classifying or visualizing data, and/or storing values or properties of process variables over time, and/or storing calculated values and/or generated signals outputting values or properties of process variables over time, and/or outputting calculated values and/or generated signals.

5. The computer-implemented method according to claim 1, wherein in step (d) the number of process variables which do not belong to any of the determined at least one subset of process variables, but are processed, comprises at least one process variable which is: processed at a lower frequency than those process variables which belong to at least one of the determined at least one subset, and/or observed by at least one processing unit to decide whether it should be included in an updated version of at least one of the determined at least one subset

6. The computer-implemented method according to claim 1, wherein in step (d) the number of process variables which do not belong to any of the determined at least one subset of process variables, but are processed, is selected according to at least one of the following criteria: values of configuration variables history of determined subsets of process variables for this production cell and/or other production cells history of generated signals which were provided by the method to an operator for this production cell and/or other production cells.

7. The computer-implemented method according to claim 1, wherein the at least one shaping machine is a cyclically operating machine, preferably an injection-molding machine, an injection press, or a compounder or a continuously operating machine, preferably an extruder.

8. The computer-implemented method according to claim 1, wherein at least one of the at least one processing unit is comprised by: an edge device a control unit of one of the subunits of the production cell or of the production cell a central server of a production site containing the production cell a stationary or mobile computing device a cloud computing device.

9. The computer implemented method according to claim 1, wherein: at least some process variables are, preferably each process variable is, associated with at least one logical group, wherein there are provided at least two different logical groups, and it is preferably provided that logical groups are arranged in at least two hierarchy levels in such a way that at least one logical group of a lower hierarchy level is associated with another logical group of a higher hierarchy level.

10. The computer implemented method according to claim 9, wherein in step (b) the at least one processing unit determines at least some of the process variables of the at least one subset of process variables out of the totality of process variables on basis of the logical structure given by the logical groups, preferably given by the hierarchical levels of logical groups.

11. The computer implemented method according to claim 10, wherein the at least one processing unit determines at least some of the process variables of the at least one subset of process variables such that all process variables belonging to a logical group are included in the at least one subset.

12. The computer implemented method according to claim 10, wherein, continuously or in time-discrete relationship, the value of a plurality of process variables is processed, and for each logical group a state of the logical group is evaluated by the at least one processing unit on the basis of the process variables associated with said logical group, and is preferably visualised by means of a display device, and wherein the state of logical groups is evaluated only for those logical groups for which all of the process variables necessary to evaluate their state belong to at least one of the at least one subset of process variables.

13. The computer implemented method according to claim 12, wherein in order to evaluate the state of a logical group the respective current value of each process variable or a variable derived therefrom is compared to one or more reference values by means of at least one processing unit and a deviation or a rate of change is determined.

14. A production cell comprising at least one shaping machine as a subunit having a plurality of actuators and/or sensors, the production cell comprising or being in connection with at least one processing unit, the at least one processing unit being configured to carry out the method according to claim 1.

15. A computer program which when it is executed by a computer having at least one processing unit causes the computer to carry out the method according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0143] Embodiments of the invention are discussed on basis of the attached Figures in which:

[0144] FIG. 1 shows a schematic drawing of a production cell having different subunits which have different actuators and sensors;

[0145] FIG. 2 shows schematically the flow of information between actuators, sensors and a processing unit;

[0146] FIG. 3 shows how different process variables are ascertained from different measurement values;

[0147] FIG. 4 shows a totality of process variables from which two subsets of process variables are chosen by way of example;

[0148] FIG. 5 shows how a processing unit uses determined subsets for processing process variables in order to generate output, here in the form of a signal for an operator;

[0149] FIG. 6 shows an example in which a processing unit decides to include a process variable not included in a subset in an updated version of the subset;

[0150] FIG. 7 shows logical groups arranged in hierarchical levels;

[0151] FIG. 8 shows a three-dimensional representation of process variables on basis of the logical structure given by the hierarchical levels of logical groups;

[0152] FIG. 9a-e shows a first example of the inventive method;

[0153] FIG. 10a-d shows a second example of the inventive method;

[0154] FIG. 11 shows a third example of the inventive method; and

[0155] FIG. 12 shows a schematic example of the inventive method.

DETAILED DESCRIPTION OF THE INVENTION

[0156] In FIG. 1 a production cell 1 comprising, by way of example, three subunits 2, one of which is a shaping machine, is shown. Each subunit 2 has actuators 3 and sensors 4 which are connected to at least one processing unit 5 (by way of example, two processing units 5 are shown).

[0157] FIG. 2 shows only some of these connections for some of the actuators 3 and sensors 4 of an exemplary subunit 2. The connections are used to communicate a plurality of measurement values m.sub.i to a processing unit 5.

[0158] FIG. 3 shows how different process variables P.sub.i are processed based on different measurement values m.sub.i.

[0159] FIG. 4 shows an example for step (b) of a computer-implemented method according to the invention (cf. also FIG. 12). Out of a totality H of process variables P.sub.i a processing unit 5 determines at least one subset S.sub.i of process variables P.sub.i. In step (c), during production of a production lot, those process variables P.sub.i which belong to the determined at least one subset S.sub.i of process variables P.sub.i are processed, e.g., in order to calculate values or properties of process variables P.sub.i over time, preferably key figures, derived from at least one process variable P.sub.i, and/or to generate signals to be provided by the method to an operator, and/or to store calculated values and/or generated signals (cf. FIG. 5).

[0160] In the example of FIG. 4 two subsets S.sub.1 and S.sub.2 are determined and two process variables P.sub.8, P.sub.9 belong to the complement C=Π\(S.sub.1∪S.sub.2). In step (c) of the method all process variables P.sub.1, . . . , P.sub.7 which belong to one of the subsets S.sub.1 and S.sub.2 are processed. With respect to the process variables P.sub.8, P.sub.9 belonging to the complement C it is preferred that they are not processed. Alternatively, it would be possible to: [0161] process them at a lower frequency than those process variables P.sub.1, . . . , P.sub.7 which belong to at least one of the determined subsets S.sub.i and S.sub.2, and/or [0162] observe them by at least one processing unit 5 to decide whether either one of them should be included in an updated version of at least one of the subsets S.sub.1 and S.sub.2 (cf. FIG. 6)

[0163] It can be provided that at least some process variables P.sub.i are, preferably each process variable P.sub.i is, associated with at least one logical group 6, wherein there are provided at least two different logical groups 6, and logical groups 6 are arranged in at least two hierarchy levels in such a way that at least one logical group 6 of a lower hierarchy level is associated with another logical group 6 of a higher hierarchy level.

[0164] In the example shown in FIG. 7 the hierarchical structure (a plurality of hierarchical levels) is shown along axis Y. At the lowest level the totality H of process variables P.sub.i is shown. At the next level logical groups 6 belonging to the lowest hierarchical level are shown. At the highest-level logical groups 6 belonging to the highest hierarchical level are shown.

[0165] It can be seen that different process variables P.sub.i are processed with respect to different logical groups 6. Also, different logical groups 6 can have different numbers of process variables P.sub.i connected to them.

[0166] It is preferred that, continuously or in time-discrete relationship, the value of a plurality of process variables P.sub.i is processed, and for each logical group 6 a state of the logical group 6 is evaluated by at least one processing unit on the basis of the process variables P.sub.i associated with said logical group 6 and is preferably visualised by means of a display device.

[0167] Bringing together the evaluation of individual process variables P.sub.i in a plurality of hierarchy levels gives an overall overview about the state of the process, starting from which the operator can provide the desired information along the hierarchical structure in various planes to the individual process variables P.sub.i, or a visualization device automatically represents those items of information to the operator.

[0168] FIG. 8 shows a three-dimensional representation (having axes X, Y, Z) of process variables P.sub.i on basis of the logical structure given by the hierarchical levels of logical groups 6 (X-Y plane) and on basis of a determined subset S.sub.i (along the Z axis).

[0169] In this Figure two different principles (top-down-approach and bottom-up-approach with respect to the Y axis) are shown which can be used alternatively or in combination:

[0170] On the left side of FIG. 8 it is determined by a processing unit 5 that logical group 6.sub.1 is not of interest and consequently the logical group 6.sub.2 belonging to a lower hierarchical level and the process variables P.sub.i of the lowest hierarchical level do not have to be processed (the process variable P.sub.2 does not belong to a determined subset S.sub.i). This is an example for the top-down-approach.

[0171] On the right side of FIG. 8 it is determined by a processing unit 5 that process variable P.sub.6 does not belong to a determined subset S.sub.i and is consequently not processed. Consequently, all of the logical groups 6.sub.3, 6.sub.4, 6.sub.5, for which the processing unit 5 needs process variable P.sub.6 as single input to determine the state of the logical group 6.sub.3, 6.sub.4, 6.sub.5 are not processed. This is an example for the bottom-up-approach.

[0172] The fact that a process variable P.sub.i or a logical group 6 is not processed is shown by shading.

[0173] It can be seen by comparing the two different X-Y planes (spaced along the Z axis) that out of the totality H of process variables P.sub.i and the totality of logical groups 6 only some process variables P.sub.i and some logical groups 6 are processed by the at least one processing unit 5, namely those process variables P.sub.i belonging to at least one determined subset S.sub.i and those logical groups 6 which have been selected as interesting or use only process variables P.sub.i belonging to at least one determined subset S.sub.i as input.

[0174] Further examples of embodiments of the invention are discussed with respect to FIGS. 9 to 11. The inventive concept is summarized with respect to FIG. 12.

[0175] FIG. 9 refers to a shaping machine with two injection units. Each one of FIGS. 9a to 9e shows a different plane with respect to the Z axis.

[0176] FIG. 9a (Z0):

[0177] Totality Π of process variables P.sub.i (three temperatures of each barrel, injection pressure in barrel1). The temperature signals will be processed by calculation of the mean values during each cycle. The temperature mean values are connected to the logical groups T_barrel1 and T_barrel2 which are connected to the logical group “T_barrels”. Injection pressure p_inj T1,1mean and T1,2mean are members of the logical group “Viscosity change”. This logical group represents an algorithm that can detect viscosity changes during production. Configuration variables barrel1used and barrel2used are shown below the X-axis.

[0178] FIG. 9b (Z1):

[0179] Barrel1 is not configured (not required for the specific production lot) and therefore the configuration variable Barrel2used is shown shaded. Monitoring the temperatures of barrel1 is not required (as determined by operator input, history of user behavior, . . . ) and therefore logical group T_barrel1 is shown shaded.

[0180] FIG. 9c (Z2):

[0181] The two different approaches as discussed before are shown, namely, on the left side the top-down-approach for reduction and on the right side the bottom-up-approach for reduction of process variables P.sub.i to be processed and logical groups to be used.

[0182] FIG. 9d (Z3)

[0183] On the right side a further bottom-up-approach to reduction with respect to the hierarchically ordered logical groups is shown.

[0184] FIG. 9e (Z4):

[0185] Shows those process variables P.sub.i which belong to a determined subset and which are therefore left for processing and the corresponding logical groups.

[0186] FIG. 10 refers to a production cell having two water manifolds for mold cooling of a shaping machine. Each one of FIGS. 10a to 10d shows a different plane with respect to the Z axis.

[0187] FIG. 10a (Z0):

[0188] Totality Π of process variables P.sub.i: Each manifold supplies two circuits wherein the water flow rate and the water temperature difference between outlet and inlet of the mold is processed (measured or calculated). Configuration variables are shown below the x-axis.

[0189] FIG. 10b (Z1):

[0190] Circuit 1 of manifold 1 is not required for the mold, Heat flow rate Q is not required.

[0191] FIG. 10c (Z2 and Z3):

[0192] Illustration of top-down-approach to reduction and bottom-up-approach to reduction as with respect to FIG. 9. No further reduction across the P.sub.i level possible.

[0193] FIG. 10d (Z4):

[0194] Shows those process variables P.sub.i which belong to a determined subset and which are therefore left for processing and the corresponding logical groups.

[0195] FIG. 11 is used to discuss an example for determination whether a process variable P.sub.i is to be included in a subset in step (b).

[0196] Whether the process variable “T1,1” is to be included in a subset (and is therefore to be processed), can be decided based on a logic operation on connections C1-C3. [0197] Connection C1 connects to configuration variable “Barrel 1 used”. [0198] Connection C2 connects to “Message algorithm M1” [0199] Connection C3 connects to logical group “Barrel 1 display”

[0200] Therefore, for process variable “T1,1” to be processed, C1 must be active. Processing of process variable “T1,1” is only required if C2 and/or C3 are active. The corresponding logical operation in this example would be C1 AND (C2 OR C3).

[0201] Examples for evaluation of logical groups: [0202] The evaluation of message algorithm M1 is only executed if the following logic operation is true: C2 AND C4 (both process variables X AND T1,1 are required) [0203] The evaluation (i.e. display) of group “Barrel 1 display” only executes if the following logic operation is true: C3 OR C5 OR C6. (at least one process variable of T1,1 T1,2 T1,3 is required). During execution only active connections are considered.

[0204] Connections in this example can have two “directions” (up/down), i.e., one connection in the drawing can correspond to two connections in reality.

[0205] FIG. 12 shows an example in which a computer-implemented method for processing a plurality of process variables P.sub.i of a production cell 1 is used (here comprising, by way of example, three subunits 2), which comprises at least one shaping machine as a subunit 2 of the production cell 1, the method using at least one processing unit 5 and comprising at least the steps of: [0206] a. for at least one subunit 2 of the production cell 1 (the at least one subunit 2 having a plurality of actuators 3 and sensors 4) providing to or determining by the at least one processing unit 5 a totality Π of process variables (P.sub.1 to P.sub.10) which is available for processing for the plurality of actuators 3 and/or sensors 4 of the at least one subunit 2 [0207] b. using the at least one processing unit 5 to determine at least one subset S.sub.i of process variables P.sub.i out of the totality H of process variables R; here, by way of example, determining subsets S.sub.1, S.sub.2 and S.sub.3 comprising different numbers of process variables P.sub.i each [0208] c. processing, during production of a production lot, those process variables P.sub.i which belong to the determined at least one subset S.sub.i of process variables P.sub.i [0209] d. for those process variables P.sub.i which do not belong to any of the determined at least one subset S.sub.i of process variables P.sub.i, processing a selected number of process variables P.sub.i; here, by way of example a single process variable P.sub.7 is selected

REFERENCE SIGNS AND TERMINOLOGY

[0210] 1 production cell [0211] 2 subunit [0212] 3 actuator [0213] 4 sensor [0214] 5 processing unit [0215] 6 logical group [0216] m.sub.i measurement value [0217] P.sub.i process variable [0218] Π totality of process variables [0219] S.sub.i determined subset of process variables [0220] C complement of ∪.sub.iS.sub.i [0221] X axis along which different process variable or logical groups are arranged at one hierarchical level [0222] Y axis along which different process variable or logical groups of different hierarchical levels are arranged [0223] Z axis which groups process variable or logical groups based on their being processed or not and to which extent they are being processed

[0224] Production Cell:

[0225] An arrangement of devices for production of products.

[0226] Subunit of a Production Cell:

[0227] At least one of the devices of a production cell.

[0228] Production Lot:

[0229] The totality of products which is produced in a given time span using a given production cell, preferably without changing a mold of the shaping machine, the totality of actuators of the production cell or the production material.

[0230] Measurement Value:

[0231] Value delivered by a sensor or a value determined on the basis of the signals delivered by the sensor, of a physical variable of the production cell, one of its subunits or the process material.

[0232] Process Variable:

[0233] Variable ascertained from a measurement value or values or a measurement value or values themselve(s); can be represented in the form of one or more key figures.

[0234] Processing a Process Variable:

[0235] The term “processing” is understood to encompass at least one of capturing or measuring data, executing data analysis (e.g., inspecting, transforming, modeling, interpreting, classifying or visualizing data) and outputting data for any kind of purpose.

[0236] Key Figure:

[0237] Variable ascertained from a process variable like for example properties of measurement curves; time at which measurement variables assume given values, and so forth.

[0238] Target Value:

[0239] Setting value for a subunit of the production cell.

[0240] Reference Value:

[0241] Value which is used for a comparison with a process variable.

[0242] Reference State:

[0243] Combination of reference values at a given time which characterizes the state of a subunit of the production cell or parts thereof at that time.

[0244] Relational Value:

[0245] Special form of a reference value, namely process variable stored at a operator-defined time for comparison with one or more process variables:

[0246] Tolerance:

[0247] Value (for example in the form of a band around a curve) which specifies from what deviation visualization and/or evaluation is affected.

[0248] Configuration of a Subunit of the Production Cell:

[0249] The selection of actuators and/or sensors used for the production of a production lot from the totality of actuators and/or sensors which is present in a given subunit of a production cell.

[0250] Configuration Variable:

[0251] Variable that shows if an actuator and or sensor is being used or not.

[0252] Processing Unit:

[0253] An entity of a processor that can independently read and execute program instructions. Each processing unit appears to the operating system as an independent processor that can be addressed in a parallel manner. Each processor provides at least one processing unit but modern processors have a plurality of cores (a core is an independent processing unit within a processor). Furthermore, each core can allow multi-threading, i.e., one physical core appears as multiple processing units to the operating system. It is to be understood that the term process encompasses CPUs, TPUs and GPUs.

[0254] Totality of Process Variables:

[0255] All process variables that can be ascertained from the measurement values (or can be in the form of a measurement value or values themselves) for the plurality of actuators and/or sensors of the at least one subunit or a static (i.e., not changing for a given configuration of a production cell) subset of process variables pre-selected therefrom.

[0256] Subset of Process Variables:

[0257] A set of process variables selected from the totality of process variables. The subset can encompass all of the process variables selected from the totality of process variables or, preferred, only some process variables selected from the totality of process variables.

[0258] Edge Device:

[0259] A device comprising a processing unit which connects subunits of a production cell or connects a production cell to an enterprise network or the cloud.