Assembly line bottleneck identification method, assembly line bottleneck identification device and assembly line bottleneck identification equipment based on industrial internet

Abstract

The invention provides an assembly line bottleneck identification method, device and equipment based on an industrial internet, and relates to the field of big data. The method comprises the following steps of: calculating the number of parts in the line-side stock based on the probability that an assembly machine is in a working state, the probability that a part supply system successfully supplies parts to the line-side stock, the maximum capacity of the line-side stock, a supply threshold value of the line-side stock, the number of the parts in the line-side stock, the working state of the part supply system and the maximum capacity of a buffer area; determining a fault rate and a repair rate of an equivalent machine formed by each assembly machine and the corresponding line side inventory, determining a blocking rate and a hunger rate of the equivalent machine based on the fault rate and the repair rate of the equivalent machine and the maximum capacity of the buffer area, and determining bottlenecks in the plurality of equivalent machines of the assembly line according to the blocking rate and the hunger rate of the equivalent machine; according to the method, the bottleneck in the assembly line is accurately identified by comprehensively considering the multi-dimensional parameters of the assembly machine, the part supply system, the line edge inventory and the buffer area.

Description

Technical Field

[0001] The present application relates to the field of big data, and in particular to an assembly line bottleneck identification method, device and equipment based on the industrial Internet. Background Art

[0002] In assembly line production, bottleneck identification can identify specific links in the production process that hinder overall efficiency improvement and cost control. By optimizing these bottlenecks, production efficiency can be improved, resource waste can be reduced, and the smooth progress of the production process can be ensured, thereby improving overall production benefits.

[0003] Traditional bottleneck identification methods mainly identify bottlenecks in the assembly line production process by quantitatively evaluating the work efficiency of the assembly line based on direct factors such as the failure rate, downtime and operation time of the assembly machines.

[0004] However, due to the complex structure of the assembly line, which involves multiple intertwined factors and links, traditional bottleneck identification methods cannot accurately identify the real bottleneck in the assembly line. Summary of the invention

[0005] The present application provides an assembly line bottleneck identification method, device and equipment based on the industrial Internet, which is used to solve the technical problem that traditional bottleneck identification methods cannot accurately identify the real bottleneck in the assembly line.

[0006] In a first aspect, the present application provides an assembly line bottleneck identification method based on the industrial Internet, wherein the assembly line includes a plurality of assembly machines that sequentially perform assembly of different parts, each of the assembly machines has a corresponding line-side inventory, the line-side inventory is used to store parts corresponding to the assembly machine, the parts in the line-side inventory are replenished by a corresponding parts replenishment system, and a buffer zone is provided between two of the assembly machines, the buffer zone is used to store work-in-progress; the method includes:

[0007] Determine the failure rate and repair rate of an equivalent machine consisting of each assembly machine and the corresponding lineside inventory based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, the working condition of the parts replenishment system, and the maximum capacity of the buffer zone;

[0008] Based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer, the blocking rate and starvation rate of the equivalent machine are determined, wherein the blocking rate of the equivalent machine is the probability that the buffer after the equivalent machine reaches the maximum capacity, the equivalent machine is in working condition, and the next equivalent machine of the equivalent machine cannot complete the assembly; the starvation rate of the equivalent machine is the probability that there is no work-in-progress in the buffer before the equivalent machine and the equivalent machine is in working condition;

[0009] According to the blocking rates and the starvation rates of the equivalent machines, bottlenecks among the multiple equivalent machines of the assembly line are determined.

[0010] In a possible implementation, the determination of the failure rate and repair rate of an equivalent machine consisting of each assembly machine and the corresponding lineside inventory based on the probability that the assembly machine is in a working state, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, the working state of the parts replenishment system, and the maximum capacity of the buffer zone includes:

[0011] Determine the initial failure rate and initial repair rate of each of the equivalent machines based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, and the working condition of the parts replenishment system;

[0012] Based on the assembly order of all equivalent machines on the assembly line, the initial failure rate and initial repair rate of each equivalent machine, and the maximum capacity of the buffer zone, the initial failure rate and initial repair rate of each equivalent machine are updated for at least one round to obtain the failure rate and repair rate of each equivalent machine.

[0013] In a possible implementation manner, based on the assembly sequence of all equivalent machines on the assembly line, the initial failure rate and initial repair rate of each equivalent machine, and the maximum capacity of the buffer, the initial failure rate and initial repair rate of each equivalent machine are updated for at least one round to obtain the failure rate and repair rate of each equivalent machine, including:

[0014] Initialize the forward aggregate failure rate and the forward aggregate repair rate of the first equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the last equivalent machine, and the forward aggregate failure rate and the forward aggregate repair rate of the other equivalent machines except the first and the last in the first round of updating based on the assembly order of all equivalent machines on the assembly line;

[0015] In each round of updating, the backward aggregate failure rate and the backward aggregate repair rate of the first equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the second equivalent machine, the initial failure rate and the initial repair rate of the second equivalent machine, and the maximum capacity of the buffer between the first equivalent machine and the second equivalent machine are used to determine the updated backward aggregate failure rate and the backward aggregate repair rate of the second equivalent machine. In addition, the forward aggregate failure rate and the forward aggregate repair rate of the third equivalent machine, the backward aggregate repair rate of the fourth equivalent machine, and the forward aggregate failure rate of the third equivalent machine are used to determine the updated backward aggregate failure rate and the backward aggregate repair rate of the fourth equivalent machine are used to determine the updated backward aggregate failure rate and the backward aggregate repair rate of the first equivalent machine. The failure rate and the backward aggregate repair rate of the fourth equivalent machine, the initial failure rate and the initial repair rate of the fourth equivalent machine, and the maximum capacity of the buffer between the third equivalent machine and the fourth equivalent machine, determine the updated forward aggregate failure rate and the forward aggregate repair rate of the fourth equivalent machine, wherein the first equivalent machine is the latter of two adjacent equivalent machines, the second equivalent machine is the previous equivalent machine of the first equivalent machine, the third equivalent machine is the former of two adjacent equivalent machines, and the fourth equivalent machine is the subsequent equivalent machine of the first equivalent machine;

[0016] Determine whether the updated backward aggregation failure rate, backward aggregation repair rate, forward aggregation failure rate and forward aggregation repair rate of each equivalent machine meet the convergence conditions. If so, determine the updated backward aggregation failure rate and forward aggregation failure rate of each equivalent machine as the failure rate of each equivalent machine, and determine the updated backward aggregation repair rate and forward aggregation repair rate of each equivalent machine as the repair rate of each equivalent machine. If not, continue to execute the next round of update.

[0017] In a possible implementation manner, determining the blocking rate and starvation rate of the equivalent machine based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer includes:

[0018] Determine the blocking rate of the fifth equivalent machine according to the initial failure rate and the initial repair rate of the fifth equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the fifth equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the sixth equivalent machine, and the maximum capacity of the buffer between the fifth equivalent machine and the sixth equivalent machine, wherein the fifth equivalent machine is any equivalent machine except the last equivalent machine, and the sixth equivalent machine is the next equivalent machine of the fifth equivalent machine;

[0019] The starvation rate of the seventh equivalent machine is determined based on the initial failure rate and initial repair rate of the seventh equivalent machine, the backward aggregation failure rate and backward aggregation repair rate of the seventh equivalent machine, the forward aggregation failure rate and forward aggregation repair rate of the eighth equivalent machine, and the maximum capacity of the buffer between the seventh equivalent machine and the eighth equivalent machine, wherein the seventh equivalent machine is any equivalent machine except the first equivalent machine, and the eighth equivalent machine is the previous equivalent machine of the seventh equivalent machine.

[0020] In a possible implementation manner, determining the bottlenecks in the multiple equivalent machines of the assembly line according to the blocking rate and the starvation rate of the equivalent machines includes:

[0021] For any equivalent machine except the last equivalent machine, according to the initial failure rate and initial repair rate of any equivalent machine, the hunger rate of the next equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine, determine the first change rate of the productivity of the assembly line with the influencing factors, wherein the influencing factors are any of the following: the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the replenishment threshold of the line-side inventory, and the maximum capacity of the line-side inventory;

[0022] For any equivalent machine except the first equivalent machine, determine the second rate of change of the productivity of the assembly line with the influencing factor according to the initial failure rate and initial repair rate of any equivalent machine, the blocking rate of the previous equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working state, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine;

[0023] A bottleneck among the plurality of equivalent machines of the assembly line is determined based on the first change rate and the second change rate.

[0024] In a possible implementation manner, determining the bottleneck in the plurality of equivalent machines of the assembly line according to the first change rate and the second change rate includes:

[0025] For the first equivalent machine, if a first change rate corresponding to the first equivalent machine is greater than a second change rate corresponding to the second equivalent machine, then the first equivalent machine is a bottleneck;

[0026] For any equivalent machine except the first equivalent machine and the last equivalent machine, if a first change rate corresponding to the any equivalent machine is greater than a second change rate corresponding to a next equivalent machine of the any equivalent machine, and the second change rate corresponding to the any equivalent machine is greater than a first change rate corresponding to a previous equivalent machine of the any equivalent machine, then the any equivalent machine is a bottleneck;

[0027] For the last equivalent machine, if the second change rate corresponding to the last equivalent machine is greater than the first change rate corresponding to the penultimate equivalent machine, the last equivalent machine is a bottleneck.

[0028] In a possible implementation, it further includes:

[0029] When there are multiple bottlenecks on the assembly line, the bottleneck severity score corresponding to each bottleneck is determined according to the first change rate and the second change rate, and the bottleneck with the largest bottleneck severity score is determined as the core bottleneck of the assembly line.

[0030] In a possible implementation manner, determining the bottleneck severity score corresponding to each bottleneck according to the first change rate and the second change rate includes:

[0031] In the case where the first equivalent machine is a bottleneck, determining a bottleneck severity score corresponding to the first equivalent machine by taking an absolute value of a difference between a first change rate corresponding to the first equivalent machine and a second change rate corresponding to the second equivalent machine;

[0032] In the case that any equivalent machine other than the first equivalent machine and the last equivalent machine is a bottleneck, the absolute value of the difference between the first change rate corresponding to the any equivalent machine and the second change rate corresponding to the next equivalent machine of the any equivalent machine, and the sum of the absolute values ​​of the difference between the second change rate corresponding to the any equivalent machine and the first change rate corresponding to the previous equivalent machine of the any equivalent machine are determined as the bottleneck severity score corresponding to the any equivalent machine;

[0033] In the case where the last equivalent machine is a bottleneck, the absolute value of the difference between the second change rate corresponding to the last equivalent machine and the first change rate corresponding to the penultimate equivalent machine is determined as the bottleneck severity score corresponding to the last equivalent machine.

[0034] In a second aspect, the present application provides an assembly line bottleneck identification device based on the industrial Internet, comprising:

[0035] A determination module, configured to determine a failure rate and a repair rate of an equivalent machine consisting of each of the assembly machines and the corresponding lineside inventory based on a probability that the assembly machine is in a working state, a probability that the parts replenishment system successfully replenishes parts for the lineside inventory, a maximum capacity of the lineside inventory, a replenishment threshold of the lineside inventory, a number of parts in the lineside inventory, a working state of the parts replenishment system, and a maximum capacity of the buffer zone;

[0036] The determination module is further configured to determine the blocking rate and starvation rate of the equivalent machine based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer, wherein the blocking rate of the equivalent machine is the probability that the buffer after the equivalent machine reaches the maximum capacity, the equivalent machine is in working condition, and the next equivalent machine of the equivalent machine cannot complete assembly; the starvation rate of the equivalent machine is the probability that there is no work-in-progress in the buffer before the equivalent machine and the equivalent machine is in working condition;

[0037] The determination module is further used to determine the bottleneck among the multiple equivalent machines of the assembly line according to the blocking rate and the starvation rate of the equivalent machines.

[0038] In a possible implementation manner, the determination module is further used to determine the initial failure rate and initial repair rate of each of the equivalent machines based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the maximum capacity of the line-side inventory, the replenishment threshold of the line-side inventory, the number of parts in the line-side inventory, and the working condition of the parts replenishment system;

[0039] The determination module is also used to update the initial failure rate and initial repair rate of each equivalent machine for at least one round based on the assembly order of all equivalent machines on the assembly line, the initial failure rate and initial repair rate of each equivalent machine, and the maximum capacity of the buffer zone to obtain the failure rate and repair rate of each equivalent machine.

[0040] In a possible implementation, the assembly line bottleneck identification device based on the industrial Internet further includes: a processing module and a judgment module;

[0041] The processing module is used to initialize the forward aggregate failure rate and the forward aggregate repair rate of the first equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the last equivalent machine, and the forward aggregate failure rate and the forward aggregate repair rate of other equivalent machines except the first and the last in the first round of updating based on the assembly order of all equivalent machines on the assembly line;

[0042] The determination module is further used to determine, in each round of updating, in a backward order based on the backward aggregate failure rate and the backward aggregate repair rate of the first equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the second equivalent machine, the initial failure rate and the initial repair rate of the second equivalent machine, and the maximum capacity of the buffer between the first equivalent machine and the second equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the second equivalent machine after updating, and, in a forward order based on the forward aggregate failure rate and the forward aggregate repair rate of the third equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the fourth equivalent machine The backward aggregate failure rate and the backward aggregate repair rate of the fourth equivalent machine, the initial failure rate and the initial repair rate of the fourth equivalent machine, and the maximum capacity of the buffer between the third equivalent machine and the fourth equivalent machine, determine the updated forward aggregate failure rate and the forward aggregate repair rate of the fourth equivalent machine, wherein the first equivalent machine is the latter of two adjacent equivalent machines, the second equivalent machine is the previous equivalent machine of the first equivalent machine, the third equivalent machine is the former of two adjacent equivalent machines, and the fourth equivalent machine is the subsequent equivalent machine of the first equivalent machine;

[0043] The judgment module is used to judge whether the updated backward aggregate failure rate, backward aggregate repair rate, forward aggregate failure rate and forward aggregate repair rate of each equivalent machine meet the convergence condition;

[0044] The determination module is also used to determine the updated backward aggregate failure rate and forward aggregate failure rate of each of the equivalent machines as the failure rate of each of the equivalent machines if the conditions are met, and determine the updated backward aggregate repair rate and forward aggregate repair rate of each of the equivalent machines as the repair rate of each of the equivalent machines if the conditions are met, and continue to execute the next round of update if the conditions are not met.

[0045] In a possible implementation manner, the determination module is further configured to determine the blocking rate of the fifth equivalent machine according to the initial failure rate and the initial repair rate of the fifth equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the fifth equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the sixth equivalent machine, and the maximum capacity of the buffer between the fifth equivalent machine and the sixth equivalent machine, wherein the fifth equivalent machine is any equivalent machine except the last equivalent machine, and the sixth equivalent machine is the next equivalent machine of the fifth equivalent machine;

[0046] The determination module is further used to determine the starvation rate of the seventh equivalent machine based on the initial failure rate and initial repair rate of the seventh equivalent machine, the backward aggregation failure rate and backward aggregation repair rate of the seventh equivalent machine, the forward aggregation failure rate and forward aggregation repair rate of the eighth equivalent machine, and the maximum capacity of the buffer between the seventh equivalent machine and the eighth equivalent machine, wherein the seventh equivalent machine is any equivalent machine except the first equivalent machine, and the eighth equivalent machine is the previous equivalent machine of the seventh equivalent machine.

[0047] In a possible implementation, the determination module is further used to determine, for any equivalent machine except the last equivalent machine, a first rate of change of the productivity of the assembly line with influencing factors based on the initial failure rate and initial repair rate of any equivalent machine, the hunger rate of the next equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine, wherein the influencing factor is any of the following: the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the replenishment threshold of the line-side inventory, and the maximum capacity of the line-side inventory;

[0048] The determination module is further used to determine, for any equivalent machine except the first equivalent machine, a second rate of change of the productivity of the assembly line with the influencing factor according to the initial failure rate and initial repair rate of the any equivalent machine, the blocking rate of the previous equivalent machine of the any equivalent machine, the probability that the assembly machine in the any equivalent machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in the any equivalent machine, the maximum capacity of the line-side inventory in the any equivalent machine, and the replenishment threshold of the line-side inventory in the any equivalent machine;

[0049] The determination module is further configured to determine a bottleneck in a plurality of equivalent machines of the assembly line according to the first change rate and the second change rate.

[0050] In a possible implementation manner, the determining module is further configured to determine, for the first equivalent machine, that if a first change rate corresponding to the first equivalent machine is greater than a second change rate corresponding to the second equivalent machine, then the first equivalent machine is a bottleneck;

[0051] The determination module is further configured to determine, for any equivalent machine except the first equivalent machine and the last equivalent machine, if a first change rate corresponding to any equivalent machine is greater than a second change rate corresponding to a next equivalent machine of the any equivalent machine, and the second change rate corresponding to any equivalent machine is greater than a first change rate corresponding to a previous equivalent machine of the any equivalent machine, then the any equivalent machine is a bottleneck;

[0052] The determination module is further configured to determine, for the last equivalent machine, that if a second change rate corresponding to the last equivalent machine is greater than a first change rate corresponding to the second-to-last equivalent machine, then the last equivalent machine is a bottleneck.

[0053] In a possible implementation, the determination module is further used to determine the bottleneck severity score corresponding to each bottleneck according to the first change rate and the second change rate when there are multiple bottlenecks on the assembly line, and determine the bottleneck with the largest bottleneck severity score as the core bottleneck of the assembly line.

[0054] In a possible implementation manner, the determination module is further configured to determine the bottleneck severity score corresponding to the first equivalent machine by taking an absolute value of a difference between a first change rate corresponding to the first equivalent machine and a second change rate corresponding to the second equivalent machine when the first equivalent machine is a bottleneck;

[0055] The determination module is further configured to, when any equivalent machine other than the first equivalent machine and the last equivalent machine is a bottleneck, determine the absolute value of the difference between the first change rate corresponding to any equivalent machine and the second change rate corresponding to the next equivalent machine of the any equivalent machine, and the sum of the absolute values ​​of the difference between the second change rate corresponding to any equivalent machine and the first change rate corresponding to the previous equivalent machine of the any equivalent machine as the bottleneck severity score corresponding to the any equivalent machine;

[0056] The determination module is further configured to determine, when the last equivalent machine is a bottleneck, an absolute value of a difference between a second change rate corresponding to the last equivalent machine and a first change rate corresponding to the second-to-last equivalent machine as a bottleneck severity score corresponding to the last equivalent machine.

[0057] In a third aspect, an embodiment of the present application provides an assembly line bottleneck identification device based on the industrial Internet, including: a memory, a processor;

[0058] The memory stores computer-executable instructions;

[0059] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementations of the first aspect.

[0060] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the first aspect above and / or various possible implementations of the first aspect.

[0061] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the above first aspect and / or various possible implementation methods of the first aspect.

[0062] The present application provides an assembly line bottleneck identification method based on the industrial Internet. The method determines the failure rate and repair rate of an equivalent machine consisting of each assembly machine and the corresponding line-side inventory based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the maximum capacity of the line-side inventory, the replenishment threshold of the line-side inventory, the number of parts in the line-side inventory, the working condition of the parts replenishment system, and the maximum capacity of the buffer zone. The blocking rate and starvation rate of the equivalent machine are determined based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer zone. The blocking rate of the equivalent machine is the probability that the buffer zone after the equivalent machine reaches the maximum capacity, the equivalent machine is in working condition, and the next equivalent machine of the equivalent machine cannot complete the assembly; the starvation rate of the equivalent machine is the probability that there is no work-in-progress in the buffer zone before the equivalent machine and the equivalent machine is in working condition. According to the blocking rate and starvation rate of the equivalent machine, the bottleneck among multiple equivalent machines of the assembly line is determined. The method calculates the failure rate, repair rate, blocking rate and starvation rate of the equivalent machine by comprehensively considering the multi-dimensional parameters of the assembly machine, the parts replenishment system, the line-side inventory and the buffer zone, thereby accurately identifying the bottleneck in the assembly line. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0064] Figure 1 A schematic diagram of the structure of the assembly line provided for this application;

[0065] Figure 2 A flow chart of the assembly line bottleneck identification method based on the industrial Internet provided in this application;

[0066] Figure 3 A schematic diagram of the structure of an assembly line bottleneck identification device based on the industrial Internet provided in this application;

[0067] Figure 4 A schematic diagram of the structure of the assembly line bottleneck identification device based on the Industrial Internet provided in this application.

[0068] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0069] Here, exemplary embodiments will be described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application.

[0070] In assembly line production, bottleneck identification can deeply analyze the production process and locate specific machines that hinder overall efficiency improvement and cost control. By optimizing these bottleneck machines, the production efficiency of the assembly line can be improved, resource waste can be greatly reduced, and the production process can be ensured to be smooth.

[0071] Traditional bottleneck identification methods rely on quantitative evaluation of assembly line efficiency, and determine bottlenecks in the production process through intuitive factors such as assembly machine failure rate, downtime, and operating time.

[0072] However, since the composition of the assembly line is quite complex and involves multiple intertwined factors and links, traditional bottleneck identification methods are difficult to accurately identify the real bottleneck in the assembly line.

[0073] In response to the above problems, the assembly line bottleneck identification method based on the industrial Internet provided in this application combines multi-dimensional information such as the operating status of the assembly machine, the efficiency of the parts replenishment system, the management parameters of the line-side inventory, and the capacity limit of the buffer zone to build an assembly line bottleneck identification system based on the industrial Internet. According to the parameters of the assembly machine and the corresponding line-side inventory, the failure rate and repair rate of each equivalent machine are calculated; combined with the maximum capacity of the buffer zone, the blocking rate (i.e., the probability of stagnation caused by the subsequent buffer being full and the subsequent equivalent machine being unable to operate) and the starvation rate (i.e., the probability that the equivalent machine is idle due to the lack of work-in-progress supply in the front buffer zone) of the equivalent machine during operation are analyzed, and the bottleneck of the assembly line is determined; this method can accurately identify potential bottlenecks in each equivalent machine on the assembly line.

[0074] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0075] Figure 1 The structural diagram of the assembly line provided for this application is as follows: Figure 1 As shown, the structural schematic diagram of the specific assembly line of this application includes:

[0076] An assembly line consists of multiple assembly machines that perform assembly of different parts in sequence , each assembly machine has a corresponding line-side inventory The line-side inventory is used to store the parts corresponding to the assembly machines. The parts in the line-side inventory are replenished by the corresponding parts replenishment system. There is a buffer between the two assembly machines. , the buffer is used to store work-in-progress.

[0077] Indicates There are assembly machines with the same and fixed operating cycle.

[0078] Indicates The line inventory corresponding to each assembly machine, the parts replenishment system adopts Inventory control strategy is line-side inventory Supplementary parts, among which, , . Line side inventory Number of parts in ,in, .

[0079] Indicates assembly machine and assembly machines Buffer between The maximum number of work-in-process in .

[0080] The workflow of the assembly line is as follows: taking the parts to be assembled as input, first, the assembly machine From line side inventory Select parts from the assembly and assemble them to the components to be assembled. After the initial assembly is completed, move them to the buffer zone. ; Next, the buffer The parts to be assembled are transported to the next assembly machine , assembly machine From line side inventory Parts are selected for assembly and then transferred to the buffer after the assembly is completed. ; This process continues until it reaches the assembly machine , assembly machine From line side inventory Pick up parts for assembly and transfer to the buffer ; Finally, the buffer of the parts to be assembled are delivered to the assembly machine , assembly machine From line side inventory Parts are selected from the final assembly and output as finished products.

[0081] Figure 2 The flowchart of the assembly line bottleneck identification method based on the industrial Internet provided in this application is shown in FIG. The execution subject of this embodiment is, for example, an assembly line bottleneck identification system. Figure 2 As shown, the assembly line bottleneck identification method based on the industrial Internet shown in this embodiment includes:

[0082] S101: Based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, the working status of the parts replenishment system, and the maximum capacity of the buffer zone, determine the failure rate and repair rate of the equivalent machine consisting of each assembly machine and the corresponding lineside inventory.

[0083] Among them, assembly machines The state of is subject to the Bernoulli reliability model. In each time period, the assembly machine by The probability of being in working state is probability of being in a fault state.

[0084] The result of the parts replenishment system for line-side inventory is subject to the parameters Bernoulli distribution, that is, at each moment The probability of line inventory The probability of successfully replenishing a part. In order to ensure the normal operation of the assembly line, it is assumed that the efficiency of the parts replenishment system is greater than the efficiency of the assembly machine, that is, .

[0085] The maximum capacity of the line side inventory is , the replenishment threshold of line inventory is , the number of parts in the line inventory is , the maximum capacity of the buffer is .

[0086] Equivalent Machine It is an assembly machine and line side inventory The independent machines consist of Equivalent machine.

[0087] Failure rate of equivalent machines Indicates The failure rate of an equivalent machine. To indicate the The probability that an equivalent machine changes from a working state to a faulty state.

[0088] Repair rate of equivalent machines Indicates Repair rate of equivalent machines. Repair rate of equivalent machines To indicate the The probability that an equivalent machine changes from a faulty state to a working state.

[0089] S102: Based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer, determine the blocking rate and starvation rate of the equivalent machine, where the blocking rate of the equivalent machine is the probability that the buffer after the equivalent machine reaches the maximum capacity, the equivalent machine is in working condition, and the next equivalent machine of the equivalent machine cannot complete the assembly; the starvation rate of the equivalent machine is the probability that there is no work-in-progress in the buffer before the equivalent machine and the equivalent machine is in working condition.

[0090] Among them, the blocking rate of the equivalent machine Indicates The blocking rate of equivalent machines. Equivalent machines in working order Unable to complete assembly job, buffer The number of work-in-progress has reached the maximum capacity , equivalent machine If the assembled work-in-progress cannot be transferred out, then the equivalent machine will be blocked, and the equivalent machine The probability of being in a blocked state is the blocking rate.

[0091] Blocking rate of equivalent machines Indicates The starvation rate of the equivalent machine. Buffer The number of work in process is zero, and the equivalent machine Failure to receive work-in-progress and equivalent machines that can be assembled In working condition, the equivalent machine will be in a state of hunger, while the equivalent machine The probability of being hungry is the hunger rate.

[0092] S103: Determine bottlenecks among multiple equivalent machines of the assembly line according to the blocking rates and starvation rates of the equivalent machines.

[0093] Among them, the bottleneck refers to the equivalent machine that has the greatest impact on the productivity of the assembly line. For example, if an equivalent machine has a greater impact on the productivity of the assembly line, it is likely that this equivalent machine is in an unhealthy state. Therefore, in order to improve the productivity of the assembly line, it is necessary to identify the bottleneck among multiple equivalent machines in the assembly line.

[0094] The assembly line bottleneck identification method based on the industrial Internet provided in this embodiment determines the failure rate and repair rate of the equivalent machine composed of each assembly machine and the corresponding line-side inventory based on the probability that the assembly machine is in working state, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the maximum capacity of the line-side inventory, the replenishment threshold of the line-side inventory, the number of parts in the line-side inventory, the working state of the parts replenishment system, and the maximum capacity of the buffer zone. Based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer zone, the blocking rate and starvation rate of the equivalent machine are determined, wherein the blocking rate of the equivalent machine is the probability that the buffer zone after the equivalent machine reaches the maximum capacity, the equivalent machine is in working state, and the next equivalent machine of the equivalent machine cannot complete the assembly; the starvation rate of the equivalent machine is the probability that there is no work-in-progress in the buffer zone before the equivalent machine and the equivalent machine is in working state. According to the blocking rate and starvation rate of the equivalent machine, the bottleneck among multiple equivalent machines of the assembly line is determined; the method calculates the failure rate, repair rate, blocking rate and starvation rate of the equivalent machine by comprehensively considering the multi-dimensional parameters of the assembly machine, the parts replenishment system, the line-side inventory and the buffer zone, thereby accurately identifying the bottleneck in the assembly line.

[0095] In a possible implementation, based on the probability that the assembly machine is in working state, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, the working state of the parts replenishment system, and the maximum capacity of the buffer zone, the failure rate and repair rate of an equivalent machine consisting of each assembly machine and the corresponding lineside inventory are determined. The specific implementation method includes:

[0096] Determine the initial failure rate and initial repair rate of each equivalent machine based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the maximum capacity of the line-side inventory, the replenishment threshold of the line-side inventory, the number of parts in the line-side inventory, and the working condition of the parts replenishment system;

[0097] Based on the assembly order of all equivalent machines on the assembly line, the initial failure rate and initial repair rate of each equivalent machine, and the maximum capacity of the buffer, the initial failure rate and initial repair rate of each equivalent machine are updated for at least one round to obtain the failure rate and repair rate of each equivalent machine.

[0098] The formula for calculating the initial failure rate of the equivalent machine is:

[0099]

[0100] The calculation formula for the initial repair rate of the equivalent machine is:

[0101]

[0102] Represents an equivalent machine Center line inventory The number of parts is 0 and the parts replenishment system is line-side inventory The probability of regular supply of parts.

[0103] The calculation formula is:

[0104]

[0105]

[0106] in, ; ; Represents an equivalent machine The state you are in; Indicates that the parts replenishment system is line-side inventory Normal supply of parts; Indicates that the parts replenishment system stops supplying parts to the line-side inventory; Represented by equivalent machines In state The probability of Represents an equivalent machine On-line inventory The number of parts is And the parts replenishment system is line-side inventory The probability of a normal supply of parts; Represents an equivalent machine Inventory at the line The number of parts is And the parts replenishment system stops being line-side inventory The probability of the state of supplying the part.

[0107] Optionally, based on the assembly sequence of all equivalent machines on the assembly line, the initial failure rate and initial repair rate of each equivalent machine, and the maximum capacity of the buffer, the initial failure rate and initial repair rate of each equivalent machine are updated for at least one round to obtain the failure rate and repair rate of each equivalent machine. The specific implementation method includes:

[0108] Initialize the forward aggregate failure rate and forward aggregate repair rate of the first equivalent machine, the backward aggregate failure rate and backward aggregate repair rate of the last equivalent machine, and the forward aggregate failure rate and forward aggregate repair rate of the other equivalent machines except the first and the last in the first round of updating based on the assembly order of all equivalent machines on the assembly line;

[0109] Initialize the forward aggregate failure rate of the first equivalent machine: , ;

[0110] Initialize the forward aggregate repair rate for the first equivalent machine: , ;

[0111] Initialize the backward aggregate failure rate of the last equivalent machine: , ;

[0112] Initialize the backward aggregate repair rate of the last equivalent machine: ;

[0113] Initialize the forward aggregate failure rates of all equivalent machines except the first and last in the first round of updates: , ;

[0114] Initialize the forward aggregate repair rates of all equivalent machines except the first and last in the first round of updates: , .

[0115] In each round of updating, in a backward-to-front order, based on the backward aggregate failure rate and the backward aggregate repair rate of the first equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the second equivalent machine, the initial failure rate and the initial repair rate of the second equivalent machine, and the maximum capacity of the buffer between the first equivalent machine and the second equivalent machine, the updated backward aggregate failure rate and the backward aggregate repair rate of the second equivalent machine are determined, wherein the first equivalent machine is the latter of two adjacent equivalent machines, and the second equivalent machine is the previous equivalent machine of the first equivalent machine;

[0116] The updated expression for the backward aggregate failure rate of the equivalent machine is:

[0117]

[0118] The updated expression for the backward aggregate repair rate of the equivalent machine is:

[0119]

[0120] in, The calculation formula is:

[0121]

[0122] = ;

[0123] ;

[0124] ;

[0125] ;

[0126] ;

[0127] ;

[0128] ;

[0129] .

[0130] Determine, in order from front to back, the updated forward aggregate failure rate and forward aggregate repair rate of the fourth equivalent machine based on the forward aggregate failure rate and the forward aggregate repair rate of the third equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the fourth equivalent machine, the initial failure rate and the initial repair rate of the fourth equivalent machine, and the maximum capacity of the buffer between the third equivalent machine and the fourth equivalent machine, wherein the third equivalent machine is the first of the two adjacent equivalent machines, and the fourth equivalent machine is the second equivalent machine of the first equivalent machine;

[0131] The updated expression for the forward aggregate failure rate of the equivalent machine is:

[0132]

[0133] The updated forward aggregate repair rate expression of the equivalent machine is:

[0134]

[0135] in, The calculation formula is:

[0136]

[0137] ;

[0138] ;

[0139] ;

[0140] ;

[0141] ;

[0142] ;

[0143] ;

[0144] .

[0145] Determine whether the updated backward aggregate failure rate, backward aggregate repair rate, forward aggregate failure rate, and forward aggregate repair rate of each equivalent machine meet the convergence conditions. The convergence conditions are:

[0146] , ;

[0147] , ;

[0148] , ;

[0149] , .

[0150] If it is satisfied, the updated backward aggregate failure rate and forward aggregate failure rate of each equivalent machine are determined as the failure rate of each equivalent machine, and the updated backward aggregate repair rate and forward aggregate repair rate of each equivalent machine are determined as the repair rate of each equivalent machine, that is, , , , , If not satisfied, proceed to the next round of updates.

[0151] In a possible implementation manner, based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer, a specific implementation manner of determining the blocking rate and starvation rate of the equivalent machine includes:

[0152] determining a blocking rate of a fifth equivalent machine according to an initial failure rate and an initial repair rate of the fifth equivalent machine, a forward aggregate failure rate and a forward aggregate repair rate of the fifth equivalent machine, a backward aggregate failure rate and a backward aggregate repair rate of the sixth equivalent machine, and a maximum capacity of a buffer between the fifth equivalent machine and the sixth equivalent machine, wherein the fifth equivalent machine is any equivalent machine except the last equivalent machine, and the sixth equivalent machine is a next equivalent machine of the fifth equivalent machine;

[0153] The blocking rate of the equivalent machine is calculated as:

[0154]

[0155] The starvation rate of the seventh equivalent machine is determined according to the initial failure rate and initial repair rate of the seventh equivalent machine, the backward aggregation failure rate and backward aggregation repair rate of the seventh equivalent machine, the forward aggregation failure rate and forward aggregation repair rate of the eighth equivalent machine, and the maximum capacity of the buffer between the seventh equivalent machine and the eighth equivalent machine, wherein the seventh equivalent machine is any equivalent machine except the first equivalent machine, and the eighth equivalent machine is the previous equivalent machine of the seventh equivalent machine.

[0156] The formula for calculating the hunger rate of an equivalent machine is:

[0157]

[0158] In one possible implementation, determining bottlenecks in a plurality of equivalent machines of an assembly line according to blocking rates and starvation rates of the equivalent machines includes:

[0159] For any equivalent machine except the last equivalent machine, according to the initial failure rate and initial repair rate of any equivalent machine, the hunger rate of the next equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine, determine the first change rate of the productivity of the assembly line with the influencing factors, where the influencing factors are any of the following: the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the replenishment threshold of the line-side inventory, and the maximum capacity of the line-side inventory;

[0160] The formula for calculating the first rate of change of the productivity of the assembly line with the influencing factor is:

[0161]

[0162] in, ; is the impact factor, Any of the following: The probability that the assembly machine is in working condition , the probability of the parts replenishment system successfully replenishing parts for line-side inventory , replenishment threshold of line side inventory , Maximum capacity of line side inventory .

[0163] For any equivalent machine except the first equivalent machine, according to the initial failure rate and initial repair rate of any equivalent machine, the blocking rate of the previous equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working state, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine, determine the second change rate of the productivity of the assembly line with the influencing factors;

[0164] The second rate of change of the productivity of the assembly line with the influencing factor is calculated as follows:

[0165]

[0166] in, ; is the impact factor, Any of the following: The probability that the assembly machine is in working condition , the probability of the parts replenishment system successfully replenishing parts for line-side inventory , replenishment threshold of line side inventory , Maximum capacity of line side inventory .

[0167] A bottleneck in a plurality of equivalent machines of an assembly line is determined based on the first rate of change and the second rate of change.

[0168] Optionally, a specific implementation method of determining the bottlenecks in the plurality of equivalent machines of the assembly line according to the first change rate and the second change rate includes:

[0169] For the first equivalent machine, if the first change rate corresponding to the first equivalent machine is greater than the second change rate corresponding to the second equivalent machine, then the first equivalent machine is a bottleneck;

[0170] Among them, the first rate of change corresponding to the first equivalent machine is , the second rate of change corresponding to the second equivalent machine is .

[0171] like , then the equivalent machine For the bottleneck.

[0172] For any equivalent machine except the first equivalent machine and the last equivalent machine, if the first change rate corresponding to any equivalent machine is greater than the second change rate corresponding to the next equivalent machine of any equivalent machine, and the second change rate corresponding to any equivalent machine is greater than the first change rate corresponding to the previous equivalent machine of any equivalent machine, then any equivalent machine is a bottleneck;

[0173] Among them, the first change rate corresponding to any equivalent machine is , the second rate of change of the next equivalent machine of any equivalent machine is , the second rate of change corresponding to any equivalent machine is , the first rate of change of the previous equivalent machine of any equivalent machine is .

[0174] like ,and , then the equivalent machine is the bottleneck, among which, .

[0175] Hypothesized impact factor The probability that the assembly machine is in working condition , , , , , , , =0.4862, , , , , ,but , , , , , , then the equivalent machine and For the bottleneck.

[0176] For the last equivalent machine, if the second change rate corresponding to the last equivalent machine is greater than the first change rate corresponding to the second-to-last equivalent machine, the last equivalent machine is a bottleneck.

[0177] Among them, the second rate of change corresponding to the last equivalent machine is , the first rate of change corresponding to the penultimate equivalent machine is .

[0178] like , then the equivalent machine For the bottleneck.

[0179] In a possible implementation, when there are multiple bottlenecks on the assembly line, the bottleneck severity score corresponding to each bottleneck is determined according to the first change rate and the second change rate, and the bottleneck with the largest bottleneck severity score is determined as the core bottleneck of the assembly line.

[0180] Optionally, a specific implementation method of determining the bottleneck severity score corresponding to each bottleneck according to the first change rate and the second change rate includes:

[0181] In the case where the first equivalent machine is a bottleneck, determining a bottleneck severity score corresponding to the first equivalent machine by taking an absolute value of a difference between a first change rate corresponding to the first equivalent machine and a second change rate corresponding to the second equivalent machine;

[0182] Among them, the first rate of change corresponding to the first equivalent machine is , the second rate of change corresponding to the second equivalent machine is , the bottleneck severity score corresponding to the first equivalent machine is .

[0183] The bottleneck severity score for the first equivalent machine is calculated as:

[0184]

[0185] In the case where any equivalent machine other than the first equivalent machine and the last equivalent machine is a bottleneck, the absolute value of the difference between the first change rate corresponding to any equivalent machine and the second change rate corresponding to the next equivalent machine of any equivalent machine, and the sum of the absolute values ​​of the difference between the second change rate corresponding to any equivalent machine and the first change rate corresponding to the previous equivalent machine of any equivalent machine are determined as the bottleneck severity score corresponding to any equivalent machine;

[0186] Among them, the first change rate corresponding to any equivalent machine is , the second rate of change of the next equivalent machine of any equivalent machine is , the second rate of change corresponding to any equivalent machine is , the first rate of change of the previous equivalent machine of any equivalent machine is , the bottleneck severity score for any equivalent machine is .

[0187] The bottleneck severity score for any equivalent machine is calculated as:

[0188]

[0189] Hypothesized impact factor The probability that the assembly machine is in working condition , , , , , , , =0.4862, , , , , , , , , , , , equivalent machine and For the bottleneck.

[0190] = , = ,

[0191]

[0192] Then, the core bottleneck of the assembly line is .

[0193] When the last equivalent machine is the bottleneck, the absolute value of the difference between the second change rate corresponding to the last equivalent machine and the first change rate corresponding to the penultimate equivalent machine is determined as the bottleneck severity score corresponding to the last equivalent machine.

[0194] Among them, the second rate of change corresponding to the last equivalent machine is , the first rate of change corresponding to the penultimate equivalent machine is , the bottleneck severity score corresponding to the last equivalent machine is .

[0195] The bottleneck severity score corresponding to the last equivalent machine is calculated as:

[0196]

[0197] Figure 3 The structural diagram of the assembly line bottleneck identification device based on the industrial Internet provided in this application is as follows: Figure 3 As shown, the assembly line bottleneck identification device 200 based on the industrial Internet provided in this embodiment includes:

[0198] A determination module 201 is used to determine the failure rate and repair rate of an equivalent machine consisting of each assembly machine and the corresponding lineside inventory based on the probability that the assembly machine is in a working state, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, the working state of the parts replenishment system, and the maximum capacity of the buffer zone;

[0199] The determination module 201 is further used to determine the blocking rate and starvation rate of the equivalent machine based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer, wherein the blocking rate of the equivalent machine is the probability that the buffer after the equivalent machine reaches the maximum capacity, the equivalent machine is in a working state, and the next equivalent machine of the equivalent machine cannot complete the assembly; the starvation rate of the equivalent machine is the probability that there is no work-in-progress in the buffer before the equivalent machine and the equivalent machine is in a working state;

[0200] The determination module 201 is further used to determine the bottlenecks among the multiple equivalent machines of the assembly line according to the blocking rates and starvation rates of the equivalent machines.

[0201] In a possible implementation, the determination module 201 is further configured to determine the initial failure rate and initial repair rate of each equivalent machine based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, and the working condition of the parts replenishment system;

[0202] Determination module 201 is also used to update the initial failure rate and initial repair rate of each equivalent machine for at least one round based on the assembly order of all equivalent machines on the assembly line, the initial failure rate and initial repair rate of each equivalent machine, and the maximum capacity of the buffer zone to obtain the failure rate and repair rate of each equivalent machine.

[0203] In a possible implementation, the assembly line bottleneck identification device based on the industrial Internet further includes: a processing module 202 and a judgment module 203;

[0204] The processing module 202 is used to initialize the forward aggregate failure rate and the forward aggregate repair rate of the first equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the last equivalent machine, and the forward aggregate failure rate and the forward aggregate repair rate of the other equivalent machines except the first and the last in the first round of updating based on the assembly order of all equivalent machines on the assembly line;

[0205] The determination module 201 is further used to determine, in each round of updating, in a backward order, based on the backward aggregate failure rate and the backward aggregate repair rate of the first equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the second equivalent machine, the initial failure rate and the initial repair rate of the second equivalent machine, and the maximum capacity of the buffer between the first equivalent machine and the second equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the second equivalent machine after updating, and, in a forward order, based on the forward aggregate failure rate and the forward aggregate repair rate of the third equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the fourth equivalent machine, the initial failure rate and the initial repair rate of the fourth equivalent machine, and the maximum capacity of the buffer between the third equivalent machine and the fourth equivalent machine, and determining the updated forward aggregate failure rate and the forward aggregate repair rate of the fourth equivalent machine, wherein the first equivalent machine is the latter of two adjacent equivalent machines, the second equivalent machine is the previous equivalent machine of the first equivalent machine, the third equivalent machine is the former of two adjacent equivalent machines, and the fourth equivalent machine is the subsequent equivalent machine of the first equivalent machine;

[0206] A judgment module 203 is used to judge whether the updated backward aggregate failure rate, backward aggregate repair rate, forward aggregate failure rate and forward aggregate repair rate of each equivalent machine meet the convergence condition;

[0207] The determination module 201 is also used to determine the backward aggregate failure rate and forward aggregate failure rate of each equivalent machine after update as the failure rate of each equivalent machine, and determine the backward aggregate repair rate and forward aggregate repair rate of each equivalent machine after update as the repair rate of each equivalent machine if the conditions are met; if not, continue to execute the next round of update.

[0208] In a possible implementation manner, the determination module 201 is further configured to determine the blocking rate of the fifth equivalent machine according to the initial failure rate and the initial repair rate of the fifth equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the fifth equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the sixth equivalent machine, and the maximum capacity of the buffer between the fifth equivalent machine and the sixth equivalent machine, wherein the fifth equivalent machine is any equivalent machine except the last equivalent machine, and the sixth equivalent machine is the next equivalent machine of the fifth equivalent machine;

[0209] Determination module 201 is also used to determine the starvation rate of the seventh equivalent machine based on the initial failure rate and initial repair rate of the seventh equivalent machine, the backward aggregation failure rate and backward aggregation repair rate of the seventh equivalent machine, the forward aggregation failure rate and forward aggregation repair rate of the eighth equivalent machine, and the maximum capacity of the buffer between the seventh equivalent machine and the eighth equivalent machine, wherein the seventh equivalent machine is any equivalent machine except the first equivalent machine, and the eighth equivalent machine is the previous equivalent machine of the seventh equivalent machine.

[0210] In a possible implementation, the determination module 201 is further used to determine, for any equivalent machine except the last equivalent machine, a first rate of change of the productivity of the assembly line with an influencing factor according to the initial failure rate and initial repair rate of any equivalent machine, the starvation rate of the next equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine, wherein the influencing factor is any of the following: the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the replenishment threshold of the line-side inventory, and the maximum capacity of the line-side inventory;

[0211] The determination module 201 is further used to determine, for any equivalent machine except the first equivalent machine, a second rate of change of the productivity of the assembly line with the influencing factor according to the initial failure rate and initial repair rate of any equivalent machine, the blocking rate of the previous equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working state, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine;

[0212] The determination module 201 is further configured to determine a bottleneck among a plurality of equivalent machines in the assembly line according to the first change rate and the second change rate.

[0213] In a possible implementation, the determination module 201 is further configured to determine, for a first equivalent machine, that if a first change rate corresponding to the first equivalent machine is greater than a second change rate corresponding to the second equivalent machine, then the first equivalent machine is a bottleneck;

[0214] The determination module 201 is further configured to determine, for any equivalent machine except the first equivalent machine and the last equivalent machine, that if a first change rate corresponding to any equivalent machine is greater than a second change rate corresponding to a next equivalent machine of any equivalent machine, and the second change rate corresponding to any equivalent machine is greater than a first change rate corresponding to a previous equivalent machine of any equivalent machine, then any equivalent machine is a bottleneck;

[0215] The determination module 201 is further configured to determine, for the last equivalent machine, if the second change rate corresponding to the last equivalent machine is greater than the first change rate corresponding to the second-to-last equivalent machine, then the last equivalent machine is a bottleneck.

[0216] In a possible implementation, the determination module 201 is further used to determine the bottleneck severity score corresponding to each bottleneck according to the first change rate and the second change rate when there are multiple bottlenecks in the assembly line, and determine the bottleneck with the largest bottleneck severity score as the core bottleneck of the assembly line.

[0217] In a possible implementation, the determination module 201 is further configured to determine the bottleneck severity score corresponding to the first equivalent machine by taking the absolute value of the difference between the first change rate corresponding to the first equivalent machine and the second change rate corresponding to the second equivalent machine when the first equivalent machine is a bottleneck;

[0218] The determination module 201 is further used to determine, when any equivalent machine other than the first equivalent machine and the last equivalent machine is a bottleneck, the absolute value of the difference between the first change rate corresponding to any equivalent machine and the second change rate corresponding to the next equivalent machine of any equivalent machine, and the sum of the absolute values ​​of the difference between the second change rate corresponding to any equivalent machine and the first change rate corresponding to the previous equivalent machine of any equivalent machine as the bottleneck severity score corresponding to any equivalent machine;

[0219] The determination module 201 is further configured to determine, when the last equivalent machine is a bottleneck, the absolute value of the difference between the second change rate corresponding to the last equivalent machine and the first change rate corresponding to the penultimate equivalent machine as the bottleneck severity score corresponding to the last equivalent machine.

[0220] The assembly line bottleneck identification device based on the industrial Internet provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effects are similar, and this embodiment will not be repeated here.

[0221] Figure 4 This is a schematic diagram of the structure of the assembly line bottleneck identification device based on the industrial Internet provided in this application. Figure 4 As shown, the electronic device 300 provided in this embodiment includes: at least one processor 301 and a memory 302. Optionally, the device 30 further includes a communication component 303. The processor 301, the memory 302 and the communication component 303 are connected via a bus 304.

[0222] In a specific implementation process, at least one processor 301 executes the computer-executable instructions stored in the memory 302, so that at least one processor 301 executes the above method.

[0223] The specific implementation process of the processor 301 can be found in the above method embodiment, and its implementation principle and technical effect are similar, so this embodiment will not be repeated here.

[0224] In the above embodiments, it should be understood that the processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the invention can be directly implemented as a hardware processor, or can be implemented by a combination of hardware and software modules in the processor.

[0225] The memory may include a high-speed memory (Random Access Memory, RAM), and may also include a non-volatile memory (NVM), such as at least one disk storage.

[0226] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus in the drawings of this application is not limited to only one bus or one type of bus.

[0227] The present application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0228] The present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the above method is implemented.

[0229] The above-mentioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The readable storage medium can be any available medium that can be accessed by a general or special-purpose computer.

[0230] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (Application Specific Integrated Circuits, referred to as: ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0231] The division of units is only a logical function division, and there may be other divisions in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0232] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0233] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0234] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0235] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk and other media that can store program codes.

[0236] Finally, it should be noted that those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variation, use or adaptation of the present invention, which follows the general principles of the present invention and includes common knowledge or conventional techniques in the art not disclosed by the present invention, is not limited to the precise structure described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof.

Claims

1. An assembly line bottleneck identification method based on industrial Internet, characterized in that: The assembly line includes a plurality of assembly machines that sequentially perform assembly of different parts, each of the assembly machines has a corresponding line-side inventory, the line-side inventory is used to store the parts corresponding to the assembly machine, the parts in the line-side inventory are replenished by a corresponding parts replenishment system, and a buffer zone is provided between two assembly machines, the buffer zone is used to store work-in-progress; the method includes: Determine the failure rate and repair rate of an equivalent machine consisting of each assembly machine and the corresponding lineside inventory based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, the working condition of the parts replenishment system, and the maximum capacity of the buffer zone; Based on the failure rate and repair rate of the equivalent machine and the maximum capacity of the buffer, the blocking rate and starvation rate of the equivalent machine are determined, wherein the blocking rate of the equivalent machine is the probability that the buffer after the equivalent machine reaches the maximum capacity, the equivalent machine is in working condition, and the next equivalent machine of the equivalent machine cannot complete the assembly; the starvation rate of the equivalent machine is the probability that there is no work-in-progress in the buffer before the equivalent machine and the equivalent machine is in working condition; According to the blocking rates and the starvation rates of the equivalent machines, bottlenecks among the multiple equivalent machines of the assembly line are determined.

2. The method according to claim 1, characterized in that The method of determining the failure rate and repair rate of an equivalent machine composed of each assembly machine and the corresponding lineside inventory based on the probability that the assembly machine is in a working state, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, the working state of the parts replenishment system, and the maximum capacity of the buffer zone includes: Determine the initial failure rate and initial repair rate of each of the equivalent machines based on the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the lineside inventory, the maximum capacity of the lineside inventory, the replenishment threshold of the lineside inventory, the number of parts in the lineside inventory, and the working condition of the parts replenishment system; Based on the assembly order of all equivalent machines on the assembly line, the initial failure rate and initial repair rate of each equivalent machine, and the maximum capacity of the buffer zone, the initial failure rate and initial repair rate of each equivalent machine are updated for at least one round to obtain the failure rate and repair rate of each equivalent machine.

3. The method according to claim 2, characterized in that Based on the assembly sequence of all equivalent machines on the assembly line, the initial failure rate and initial repair rate of each equivalent machine, and the maximum capacity of the buffer, the initial failure rate and initial repair rate of each equivalent machine are updated for at least one round to obtain the failure rate and repair rate of each equivalent machine, including: Initialize the forward aggregate failure rate and the forward aggregate repair rate of the first equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the last equivalent machine, and the forward aggregate failure rate and the forward aggregate repair rate of the other equivalent machines except the first and the last in the first round of updating based on the assembly order of all equivalent machines on the assembly line; In each round of updating, the backward aggregate failure rate and the backward aggregate repair rate of the first equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the second equivalent machine, the initial failure rate and the initial repair rate of the second equivalent machine, and the maximum capacity of the buffer between the first equivalent machine and the second equivalent machine are used to determine the updated backward aggregate failure rate and the backward aggregate repair rate of the second equivalent machine. In addition, the forward aggregate failure rate and the forward aggregate repair rate of the third equivalent machine, the backward aggregate repair rate of the fourth equivalent machine, and the forward aggregate failure rate of the third equivalent machine are used to determine the updated backward aggregate failure rate and the backward aggregate repair rate of the fourth equivalent machine are used to determine the updated backward aggregate failure rate and the backward aggregate repair rate of the first equivalent machine. The failure rate and the backward aggregate repair rate of the fourth equivalent machine, the initial failure rate and the initial repair rate of the fourth equivalent machine, and the maximum capacity of the buffer between the third equivalent machine and the fourth equivalent machine, determine the updated forward aggregate failure rate and the forward aggregate repair rate of the fourth equivalent machine, wherein the first equivalent machine is the latter of two adjacent equivalent machines, the second equivalent machine is the previous equivalent machine of the first equivalent machine, the third equivalent machine is the former of two adjacent equivalent machines, and the fourth equivalent machine is the subsequent equivalent machine of the first equivalent machine; Determine whether the updated backward aggregation failure rate, backward aggregation repair rate, forward aggregation failure rate and forward aggregation repair rate of each equivalent machine meet the convergence conditions. If so, determine the updated backward aggregation failure rate and forward aggregation failure rate of each equivalent machine as the failure rate of each equivalent machine, and determine the updated backward aggregation repair rate and forward aggregation repair rate of each equivalent machine as the repair rate of each equivalent machine. If not, continue to execute the next round of update.

4. The method according to claim 3, characterized in that The determining of the blocking rate and the starvation rate of the equivalent machine based on the failure rate and the repair rate of the equivalent machine and the maximum capacity of the buffer zone comprises: Determine the blocking rate of the fifth equivalent machine according to the initial failure rate and the initial repair rate of the fifth equivalent machine, the forward aggregate failure rate and the forward aggregate repair rate of the fifth equivalent machine, the backward aggregate failure rate and the backward aggregate repair rate of the sixth equivalent machine, and the maximum capacity of the buffer between the fifth equivalent machine and the sixth equivalent machine, wherein the fifth equivalent machine is any equivalent machine except the last equivalent machine, and the sixth equivalent machine is the next equivalent machine of the fifth equivalent machine; The starvation rate of the seventh equivalent machine is determined based on the initial failure rate and initial repair rate of the seventh equivalent machine, the backward aggregation failure rate and backward aggregation repair rate of the seventh equivalent machine, the forward aggregation failure rate and forward aggregation repair rate of the eighth equivalent machine, and the maximum capacity of the buffer between the seventh equivalent machine and the eighth equivalent machine, wherein the seventh equivalent machine is any equivalent machine except the first equivalent machine, and the eighth equivalent machine is the previous equivalent machine of the seventh equivalent machine.

5. The method according to claim 3 or 4, characterized in that: The step of determining the bottlenecks in the plurality of equivalent machines of the assembly line according to the blocking rate and the starvation rate of the equivalent machines comprises: For any equivalent machine except the last equivalent machine, according to the initial failure rate and initial repair rate of any equivalent machine, the hunger rate of the next equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine, determine the first change rate of the productivity of the assembly line with the influencing factors, wherein the influencing factors are any of the following: the probability that the assembly machine is in working condition, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory, the replenishment threshold of the line-side inventory, and the maximum capacity of the line-side inventory; For any equivalent machine except the first equivalent machine, determine the second rate of change of the productivity of the assembly line with the influencing factor according to the initial failure rate and initial repair rate of any equivalent machine, the blocking rate of the previous equivalent machine of any equivalent machine, the probability that the assembly machine in any equivalent machine is in working state, the probability that the parts replenishment system successfully replenishes parts for the line-side inventory in any equivalent machine, the maximum capacity of the line-side inventory in any equivalent machine, and the replenishment threshold of the line-side inventory in any equivalent machine; A bottleneck among the plurality of equivalent machines of the assembly line is determined based on the first change rate and the second change rate.

6. The method according to claim 5, characterized in that The step of determining the bottleneck in the plurality of equivalent machines of the assembly line according to the first change rate and the second change rate comprises: For the first equivalent machine, if a first change rate corresponding to the first equivalent machine is greater than a second change rate corresponding to the second equivalent machine, then the first equivalent machine is a bottleneck; For any equivalent machine except the first equivalent machine and the last equivalent machine, if a first change rate corresponding to the any equivalent machine is greater than a second change rate corresponding to a next equivalent machine of the any equivalent machine, and the second change rate corresponding to the any equivalent machine is greater than a first change rate corresponding to a previous equivalent machine of the any equivalent machine, then the any equivalent machine is a bottleneck; For the last equivalent machine, if the second change rate corresponding to the last equivalent machine is greater than the first change rate corresponding to the penultimate equivalent machine, the last equivalent machine is a bottleneck.

7. The method according to claim 6, characterized in that Also includes: When there are multiple bottlenecks on the assembly line, the bottleneck severity score corresponding to each bottleneck is determined according to the first change rate and the second change rate, and the bottleneck with the largest bottleneck severity score is determined as the core bottleneck of the assembly line.

8. The method according to claim 7, characterized in that The determining the bottleneck severity score corresponding to each bottleneck according to the first change rate and the second change rate includes: In the case where the first equivalent machine is a bottleneck, determining a bottleneck severity score corresponding to the first equivalent machine by taking an absolute value of a difference between a first change rate corresponding to the first equivalent machine and a second change rate corresponding to the second equivalent machine; In the case that any equivalent machine other than the first equivalent machine and the last equivalent machine is a bottleneck, the absolute value of the difference between the first change rate corresponding to the any equivalent machine and the second change rate corresponding to the next equivalent machine of the any equivalent machine, and the sum of the absolute values ​​of the difference between the second change rate corresponding to the any equivalent machine and the first change rate corresponding to the previous equivalent machine of the any equivalent machine are determined as the bottleneck severity score corresponding to the any equivalent machine; In the case where the last equivalent machine is a bottleneck, the absolute value of the difference between the second change rate corresponding to the last equivalent machine and the first change rate corresponding to the penultimate equivalent machine is determined as the bottleneck severity score corresponding to the last equivalent machine.

9. An assembly line bottleneck identification device based on the industrial Internet, characterized in that: include: Memory, processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the processor performs the method according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 8 when executed by a processor.

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