The present disclosure generally relates to material resource planning and capacity resource planning and, more particularly, to a system and method for providing high-mix wheels to material resource planning and capacity resource planning, among other features.
Current planning algorithms support only classic wheels, i.e., fixed duration of the wheel and fixed production quantity of every product in a company's existing SAP® ERP/SCM system, or similar system. Actual planning with classic wheels is based solely on the design. The High-Mix Rhythm Wheel also includes current netting situation. Moreover, levelling capacity versus demand is done in an iterative way and not in one step, reducing optimization options and also reducing performance. Additionally, manual adjustments are applied after the scheduling, reducing the possible effect of factoring.
The present disclosure overcomes the limitations and problems as described above.
In one aspect, LEAN Suite features described herein may enhance known Lean Planning concepts by adding High-Mix Wheels to the feature set and may also combine Lean Planning concepts with an automatic MRP (material resource planning) and CRP (capacity resource planning) logic enhanced by factoring algorithms. Lean Planning may now be executed in the application, including design, optimization, execution and monitoring of the Lean Planning process. Furthermore, as part of the features of the present disclosure, this is the first time that MRP, CRP and factoring against constraints can be done in one single planning step, enabling better and faster planning results. Also, extremely tight integration of planning optimization based on Lean Planning paradigm that may include enhanced Lean Planning algorithms that extend rhythmic planning.
In one aspect, the present disclosure includes one-step finite scheduling, including MRP & CRP, as well as freely interchangeable factoring methods in one cycle, thereby reducing run times compared to a standard infinite MRP process by around a factor of 2; and for the current standard planning procedure (e.g., finite MRP with additional scheduling heuristic) by a factor of 5 to 20 for same system basis and hardware. The system and method described in the present disclosure may include Customizable Factoring Methods (influencing the scheduling result). The present disclosure includes High-Mix Rhythm Wheels. In contrast, up to now, only static Rhythm Wheels have been used.
In one aspect, the present disclosure includes a Rhythm Wheel Designer module that provides setup optimization procedures against actual demands, costs and capacity constraints; optimization of Rhythm Wheels also against setup/overall costs; optimization including multi-stage stock optimization with synchronized Rhythm Wheels across different production stages, and support of different Rhythm Wheel types Classes, Breathing, High-Mix, in one tool.
In one aspect, the present disclosure includes a Rhythm Wheel Heuristic module that provides for fully integrated in-memory calculation of planning; automatic scheduling algorithms, including MRP, CRP and various factoring methods in one go, thereby supporting different Wheel types in one application. The present disclosure also includes a Rhythm Wheel Monitor module that comprises an integrated tool to compare Rhythm Wheel Design versus Rhythm Wheel Schedule against current netting settings.
The features of the present disclosure may provide far better performance, such as, e.g., allowing not only nightly batch schedules, but also fully optimized runs over the working time with the option to do several iterations by the planners in case of design changes. Moreover, dramatic reduction of the bullwhip effect on upstream production stages may be achieved by using high-mix rhythm wheels. This may provide for a Higher OEE (overall equipment effectiveness) with an ROI (return on investment) of tip to 4 Mio for a resource.
In one aspect, a system for advanced material resource planning and capacity resource planning comprises a rhythm wheel designer subsystem executing on a supply chain planning system that creates an optimal rhythm wheel design based on actual production requirements and availability of production resources using at least one sequence optimization algorithm of a plurality of sequence optimization algorithms, selectable by a user, and a rhythm wheel heuristic subsystem executing on an enterprise resource system that initializes a wheel including planning parameters, pre-calculate cycles including netting and factoring, schedules a cycle and produces a rhythm wheel log based on the optimal rhythm wheel design for controlling a production manufacturing process. The system may further include a rhythm wheel log subsystem that creates a sequence optimized material resources planning (MRP) and capacity requirements planning (CRP) production plan based on the rhythm wheel log for controlling a production manufacturing process. The rhythm wheel log subsystem may output key performance indicators to a data warehouse.
The system may further comprise a rhythm wheel monitor subsystem to accept data from the rhythm wheel log subsystem to display planning results and key performance indicators to one or more display devices. The at least one sequence optimization algorithm may comprise a plurality of optimization algorithms selected from the group of: sequence optimization, ant colony sequence optimization, simulated annealing sequence optimization and absolute minimum sequence optimization. The rhythm wheel heuristic subsystem may perform factoring if an actual required total cycle length of a created production schedule exceeds or falls below a predefined maximum or minimum cycle length. The factoring may reduce replenishment quantities which cover actual net requirements to fit actual constraints. The actual constraints may comprise one or more of: resource capacity, component availability and order prioritization cycle time definitions. The rhythm wheel designer subsystem may provide selectable optimization techniques for calculation of sequences and optimal cycle time. The selectable optimization techniques for calculation of sequences and optimal cycle time may include set-up time for overall equipment efficiency (OEE). The selectable optimization techniques for calculation of sequences and optimal cycle time may include production costs. The rhythm wheel designer subsystem may support a classic wheel rhythm wheel, a breathing rhythm wheel and a high-mix rhythm wheel. The rhythm wheel designer subsystem may outputs a centralized status display area to convey: a first status indicator that at least one product data structure (PDS) exists which is valid for a whole wheel horizon, a second status indicator during the whole wheel horizon at any time at least one valid PDS exists and a third status indicator indicating that there is at least one time period where no valid PDS exists.
In one aspect, a system for advanced material resource planning and capacity resource planning may comprise a rhythm wheel designer subsystem executing on a supply chain planning system that creates an optimal rhythm wheel design based on actual production requirements and availability of production resources using at least one sequence optimization algorithm of a plurality of sequence optimization algorithms, selectable by a user, a rhythm wheel heuristic subsystem executing on the supply chain planning system that initializes a wheel including planning parameters, pre-calculate cycles including netting and factoring, schedules a cycle and produces a rhythm wheel log based on the optimal rhythm wheel design for controlling a production manufacturing process, a rhythm wheel log subsystem executing on the supply chain planning system that creates a sequence optimized material resources planning (MRP) and capacity requirements planning (CRP) production plan based on the wheel log based on the rhythm wheel log for controlling a production manufacturing process and a rhythm wheel monitor subsystem executing on the supply chain planning system to accept data from the rhythm wheel log subsystem to display planning results and key performance indicators to one or more display devices for use by a user, wherein the system permits a single planning step to create a sequence optimized material requirements planning (MRP) and capacity requirements planning log based on the optimal rhythm wheel design and actual net requirements including factoring against existing constraints. The rhythm wheel heuristic subsystem may perform factoring if an actual required total cycle length of a created production schedule exceeds or falls below a predefined maximum or minimum cycle length.
In one aspect, a method for advanced material resource planning and capacity resource planning may comprise creating on a supply chain planning system an optimal rhythm wheel design based on actual production requirements and availability of production resources using at least one sequence optimization algorithm of a plurality of sequence optimization algorithms, selectable by a user and initializing a wheel including planning parameters, pre-calculating cycles including netting and factoring, scheduling a cycle and producing a rhythm wheel log based on the optimal rhythm wheel design for controlling a production manufacturing process. The method may further comprise creating a sequence optimized material resources planning (MRP) and capacity requirements planning (CRP) production plan based on the rhythm wheel log for controlling a production manufacturing process. The method may further comprise outputting key performance indicators to a data warehouse.
The method may further comprise accepting data from the rhythm wheel log subsystem and displaying planning results and key performance indicators to one or more display devices. The at least one sequence optimization algorithm may comprise a plurality of optimization algorithms selected from the group of: sequence optimization, ant colony sequence optimization, simulated annealing sequence optimization and absolute minimum sequence optimization.
The accompanying drawings, which are included to provide a further understanding of the disclosure, are incorporated by reference in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the detailed description serve to explain the principles of the disclosure No attempt is made to show structural details of the disclosure in more detail than may be necessary for a fundamental understanding of the disclosure and the various ways in which it may be practiced. In the drawings:
The disclosure and the various features and advantageous details thereof are explained more fully with reference to the non-limiting examples that are described and/or illustrated in the accompanying drawings and detailed in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale, and features of one example may be employed with other examples as the skilled artisan would recognize, even if not explicitly stated herein. Descriptions of well-known components and processing techniques may be omitted so as to not unnecessarily obscure the principles of the disclosure. The examples used herein are intended merely to facilitate an understanding of ways in which the disclosure may be practiced and to further enable those of skill in the art to practice the features and capabilities of the disclosure. Accordingly, the examples herein should not be construed as limiting the scope of the disclosure. Moreover, it is noted that like reference numerals represent similar parts throughout the several views of the drawings. The features described herein may be performed on a server, a computer and may be performed within a networks environment.
A “computer”, as used in this disclosure, means any machine, device, circuit, component, or module, or any system of machines, devices, circuits, components, modules, or the like, which are capable of manipulating data according to one or more instructions, such as, for example, without limitation, a processor, a microprocessor, a central processing unit, a general purpose computer, a super computer, a personal computer, a laptop computer, a palmtop computer, a notebook computer, a desktop computer, a workstation computer, a server, or the like, or an array of processors, microprocessors, central processing units, general purpose computers, super computers, personal computers, laptop computers, palmtop computers, notebook computers, desktop computers, workstation computers, servers, or the like. Further, the computer may include an electronic device configured to communicate over a communication link. The electronic device may include a computing device, for example, but is not limited to, a mobile telephone, a personal data assistant (PDA), a mobile computer, a stationary computer, a smart phone, mobile station, user equipment, or the like.
A “server”, as used in this disclosure, means any combination of software and/or hardware, including at least one application and/or at least one computer to perform services for connected clients as part of a client-server architecture. The at least one server application may include, but is not limited to, for example, an application program that can accept connections to service requests from clients by sending back responses to the clients. The server may be configured to run the at least one application, often under heavy workloads, unattended, for extended periods of time with minimal human direction. The server may include a plurality of computers configured, with the at least one application being divided among the computers depending upon the workload. For example, under light loading, the at least one application can run on a single computer. However, under heavy loading, multiple computers may be required to run the at least one application. The server, or any if its computers, may also be used as a workstation.
A “database” as used in this disclosure, means any combination of software and/or hardware, including at least one application and/or at least one computer. The database may include a structured collection of records or data organized according to a database model, such as, for example, but not limited to at least one of a relational model, a hierarchical model, a network model or the like. The database may include a database management system application (DBMS) as is known in the art. The at least one application may include, but is not limited to, for example, an application program that can accept connections to service requests from clients by sending back responses to the clients. The database may be configured to run the at least one application, often under heavy workloads, unattended, for extended periods of time with minimal human direction.
A “network,” when used in a computer network sense, means an arrangement of two or more communication links. A network may include, for example, the Internet, a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), a personal area network (PAN), a campus area network, a corporate area network, a global area network (GAN), a broadband area network (BAN), any combination of the foregoing, or the like. The network may be configured to communicate data via a wireless and/or a wired communication medium. The network may include any one or more of the following topologies, including, for example, a point-to-point topology, a bus topology, a linear bus topology, a distributed bus topology, a star topology, an extended star topology, a distributed star topology, a ring topology, a mesh topology, a tree topology, or the like. Online refers to and includes activity on a network by connected users of the network. A “communication link”, as used in this disclosure, means a wired and/or wireless medium that conveys data or information between at least two points. The wired or wireless medium may include, for example, a metallic conductor link, a radio frequency (RF) communication link, an Infrared (IR) communication link, an optical communication link, or the like, without limitation. The RF communication link may include, for example, WiFi, WiMAX, IEEE 802.11, DECT, 0G, 1G, 2G, 3G or 4G cellular standards, Bluetooth, or the like.
The terms “including”, “comprising” and variations thereof, as used in this disclosure, mean “including, but not limited to”, unless expressly specified otherwise.
The terms “a”, “an”, and “the”, as used in this disclosure, means “one or more”, unless expressly specified otherwise.
The term “cycle”, as used in this disclosure, means the time which a rhythm wheel needs to produce the designed sequence of products once.
Devices that are in communication with each other need not be in continuous communication with each other, unless expressly specified otherwise. In addition, devices that are in communication with each other may communicate directly or indirectly through one or more intermediaries. Although process steps, method steps, algorithms, or the like, may be described in a sequential order, such processes, methods and algorithms may be configured to work in alternate orders. In other words, any sequence or order of steps that may be described does not necessarily indicate a requirement that the steps be performed in that order. The steps of the processes, methods or algorithms described herein may be performed in any order practical. Further, some steps may be performed simultaneously.
When a single device or article is described herein, it will be readily apparent that more than one device or article may be used in place of a single device or article. Similarly, where more than one device or article is described herein, it will be readily apparent that a single device or article may be used in place of the more than one device or article. The functionality or the features of a device may be alternatively embodied by one or more other devices which are not explicitly described as having such functionality or features.
A “computer-readable medium”, as used in this disclosure, means any medium that participates in providing data (for example, instructions) which may be read by a computer. Such a medium may take many forms, including non-transitory media or storage, non-volatile media, volatile media, and transmission media. Non-volatile media may include, for example, optical or magnetic disks and other persistent memory. Volatile media may include dynamic random access memory (DRAM). Transmission media may include coaxial cables, copper wire and fiber optics, including the wires that comprise a system bus coupled to the processor. Transmission media may include or convey acoustic waves, light waves and electromagnetic emissions, such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes or altered make-up, a RAM, a PROM, an EPROM, a FLASHEEPROM, any other memory chip or cartridge, or any other tangible medium from which a computer can read. A computer program product having the software for performing the features described herein may include a non-transitory computer-readable medium having the software stored thereon that when read and executed by a computer, performs ten features herein.
Various forms of computer readable media may be involved in carrying sequences of instructions to a computer. For example, sequences of instruction (i) may be delivered from a RAM to a processor, (ii) may be carried over a wireless transmission medium, and/or (iii) may be formatted according to numerous formats, standards or protocols, including, for example, WiFi, WiMAX, IEEE 802.11, DECT, 0G, 1G, 2G, 3G or 4G cellular standards, Bluetooth, or the like.
The various flow diagrams may also represent a block diagram of software components that when read and executed by an appropriate hardware computing platform that includes a computer may execute the steps described.
The present disclosure provides a system and method for advanced features for material resource planning and capacity resource planning and, more particularly, a system and method for providing high-mix wheels to material resource planning and capacity resource planning, among other features, such as for use in a SAP ERP/SCM system, using integration capacities of these platforms.
The present disclosure includes an integrated approach for Design, Planning and Monitoring of rhythmic production planning by way of:
Also included is an algorithm for automatically factored (adoption of planning result to ensure the adherence of the design constraints. For High-Mix Rhythm Wheels, these are in general the resource capacity, the minimum and maximum Cycle time of a wheel) High-Mix Rhythm Wheel Planning. This algorithm is a new planning approach, simultaneously providing Material Requirement Planning (MRP) and Capacity Requirement Planning (CRP), including various factoring methods and scheduling. Also provided is an ability of the planner to freely combine different factoring methods before the planning is executed to achieve optimal results under the given constraints (Capacity, Demand, Stock, Rhythm Wheel Cycle time) without any manual intervention.
Due to the fact that all calculations may be done as single in-memory calculation, a much higher performance and planning simplification can be achieved compared to the approach of existing Advanced Planning and Scheduling (APS) systems (e.g., factors 5-20 to a comparable standard SAP APO PP/DS planning) where the process is done sequentially (First MRP, then CRP based scheduling and then manual factoring by the planner).
The RWD subsystem 1300 (as well as the RWH subsystem 1400, RWL subsystem 1500 and RWM subsystem 1600) may be a SAP® APO add-on. The RWD subsystem 1300 may provide for the maintenance and configuration of Rhythm Wheel designs, and besides Rhythm Wheel scheduling and monitoring, one of the three constituents of the Rhythm Wheel planning landscape.
The RWD subsystem 1300 may enable a holistic process from data upload, identification of the setup optimal product sequence and calculation of cycle length, the maintenance of additional wheel configuration, evaluation of configuration by several KPIs and final adjustments to release for planning as well as the simulation of various based on different design settings. The output of the RWD subsystem 1300 process is an optimized production wheel with ideal product sequence and make-quantities for levelled production, based on the optimization constraints (e.g. OEE, costs). In the medium and long-term horizon, a renewal of parameter settings and configurations (product mix, sequence, quantities) is necessary to incorporate changes of demand patterns (volatility, trends etc.).
Referring to
The RWD subsystem 1300 may have a plurality of modules to calculate cycle times 1312, optimize sequences 1314, maintain Rhythm Wheel types and further planning parameters 1316, and maintain factoring methods 1318. The RWD subsystem 1300 may provide the output, such as the Rhythm Wheel design parameters 1402, from the modules 1312, 1314, 1316, 1318 to the RWH subsystem 1400. The RWH subsystem 1400 may have a plurality of modules, including an initialization module 1412 to initialize a wheel, and including all planning parameters, a product sorting field adapter 1404 (for later visualization), a pre-calculating module 1414 to pre-calculate cycles including netting and factoring, a cycle scheduling module 1416 and a rhythm wheel log module 1418 to produce rhythm wheel log 1502. The pre-calculating module 1414 may accept input or have access to planning method adapter 1406, a make quantity adapter 1411 for the netting algorithm and the factoring adapter 1413, an adapter to shift data from a resource 1408, and transactional data 1410.
Within the RWD entry screen, the user is able to select a design range by filtering using filter button 113 according to specific selection criteria. Possible selection criteria are:
As shown in
As shown in
Attributes from the Advanced Planner and Optimizer (APO) resource master of the SCM system may be used in order to calculate the cycle time. By clicking on the “Resource Parameters” 125 button the user may enter the resource screen of the RWD, shown in
The user can load all products on the selected resource automatically. Due to the fact that not every product needs to be considered on one production asset, the user is able to add or remove products included in the RW configuration 132. For the selected products, the Product Number 135, Product Description 137, and ABC Classification 140 may be displayed as shown in
If at least one product exists with a red PDS traffic light, the wheel design cannot be completed. The following rule selects the PDS for the Wheel design:
The following data can be loaded from APO automatically on request but can also be adjusted manually:
During the design of a Wheel, the planner has to maintain per product either an annual frequency 148 of production or a manual minimum make quantity (MMMQ) 149 which is an economical lot size to let the system calculate a minimum make quantity (MMQ) 150. The MMQ is not to mistake with the minimum lot size and is taken into account by the RWD for the cycle time calculation as well as by the RWH subsystem 1400. As soon as the product master and transactional data is maintained and the user goes back to the overview screen (
On the basis of the data defined in the maintenance of resources and products (e.g.,
As shown in
The ant colony adapter can be used for all kinds of sequence optimizing problems. It is recommended to use this adapter especially for material combinations when some materials can be produced after others. As the ant colony algorithm is a constructive heuristic, the probability of finding a producible sequence is higher than, for example, as nearest neighbor and simulated annealing. The ant colony heuristic outputs the best sequence it calculated.
As shown in
The simulated annealing adapter can be used for sequence optimization problems with complete setup matrix. Simulated annealing uses nearest neighbor heuristic to construct the initial sequence. Therefore, it is possible that the heuristic lacks finding sequences when using incomplete setup matrices. As Simulated Annealing works with many sequences, its output is the best sequence that was worked with.
As shown in
The absolute minimum adapter should be used if the amount of regarded materials is lower or equal to 10 as it delivers the minimal solution. The absolute minimum algorithm calculates the minimum sequence.
As shown in
As shown in
Based on all the maintained product and resource data the RWD subsystem 1300 is able to calculate the so-called estimated cycle time. The cycle time calculation is an approximation procedure. And may be based on the reference demand of the products allocated on the wheel, including the dummy product for non RW products. With regard to estimated production times and the working time available, the campaign size is minimized in order to level production as much as possible.
Estimated Cycle Time Calculation:
1. Iteration
2. Iteration
Definition of planned cycle time and cycle time boundaries:
Based on the estimated cycle time the user defines a planned cycle time as well as cycle time boundaries. The planned cycle time should not be higher than the estimated cycle time.
As soon as the planned cycle time is maintained, the RWD subsystem 1300 may propose a minimum cycle time of 75% of the planned cycle time and a maximum cycle time of 125%. The user may need to review these figures and update them manually if required. The Rhythm Wheel heuristic subsystem 1400 may take these figures into account when scheduling the Orders. The cycle time boundaries may be exceeded.
The Rhythm Wheel Designer subsystem 1300 may support three Rhythm Wheel types:
For a homogenous product mix with rather constant demand, every product is scheduled every cycle. The Classic Rhythm Wheel produces fixed quantities according to a fixed schedule. The Breathing Rhythm Wheel produces fixed quantities according to a fixed schedule. For a high mix portfolio, the High-Mix Rhythm Wheel may be favorable to define different production rhythms. For example, low volume products are not scheduled every cycle to avoid high set-up times compared with the effective production time. The average cycle may be shortened which saves cycle stock for high.
As shown in
As illustrated in
Minimum factoring is required if the actual cycle time falls below the minimum cycle time boundary. If the cycle time of a wheel is below the minimum cycle time, the RWH subsystem 1400 may automatically postpone the next cycle until the minimum cycle time requirement is met. This may result in idle time on the resource. The idle time can be used for maintenance, training, continuous improvement or other activities that are frequently required.
Maximum factoring refers to the shortening of the Rhythm Wheel cycle time. There exist various methods for reducing the cycle time, which can be combined with each other. Make to Order (MTO) products and fixed orders must be excluded from factoring. In case of MTO products or fixed orders, the production quantity and due dates must coincide with the order quantity and date to deliver on time in full (OTIF).
Maximum factoring—Default factoring (De-allocated): as illustrated in
As illustrated in
As illustrated in
As illustrated in
When creating a Rhythm Wheel, various ATP categories can be defined which are not taken into account by the Rhythm Wheel heuristic at all. The heuristic does not schedule any planned orders for these categories since they are not considered in the netting. Furthermore, it is possible to maintain ATP categories which are considered as MTO orders by the heuristic.
Rhythm Wheel Report KPIs: the RWD subsystem 1300 may be equipped with functionality for predicting the impact of a Rhythm Wheel design on relevant performance indicators. This functionality provides important support for planners seeking the right pre-configuration of their rhythm-managed production assets.
Within a Rhythm Wheel Report as illustrated in
As illustrated in
Rhythm Wheel Heuristic
Based on a Rhythm Wheel design created in the RWD subsystem 1300, the SAP APO system, or similar system, can schedule orders in the optimal sequence and quantity. The latest demand information from the supply chain network may be used for this automated activity. In case of no demand or demand lower than the minimum make quantity for a Stock Keeping Unit (SKU), the RWH subsystem 1400 may skip this SKU during the current cycle and will take it into account during cycle, if there is relevant demand available.
To prevent cycles of the Rhythm Wheel from becoming continuously shorter (or longer), factoring methods (explained more below) are typically used. The following factoring methods are always active:
For the creation of the optimal production schedule, the RWH subsystem 1400 may take the following main parameters and characteristics into account:
The Rhythm Wheel Heuristic planning horizon is divided into the short-term horizon and long-term horizon. In these horizons the calculation order-quantities and handling of exceptions may be treated differently. In the short-term horizon, the concept typically covers real consumption only. This means produced material quantities always refer to a specified Replenishment Level, the IRL (Inventory Replenishment Level), and not to a forecast. But for an accurate procurement, already in the short term horizon, a forecast share is considered within the planned orders behind a changeable figure (x-line). The orders in the long term horizon are calculated on a Projected Inventory PI which is based on the current inventory and future planned requirements and receipts.
The RWH subsystem 1400 may perform the following planning steps during execution: Initialize the wheel: to initialize the wheel, the current wheel and the resource are prepared for the Rhythm Wheel scheduling.
Cyclic Planning of the Wheels
At the start of each new cycle, the system checks if a new valid wheel is available. If there are two valid wheels available, the one with the higher priority will be used.
In the pre-calculation, the RWH subsystem 1400 may calculate the orders to be scheduled for the current cycle based on the RW Design, the current inventory and the lot size profile of the products. If necessary, orders can be split into different lots based on lot sizes and rounding values. If the overall cycle time is longer than the maximum cycle time from the RWD subsystem 1300, the RWH subsystem 1400 may check if factoring methods are assigned to the wheel and executes them. The result of the pre-calculation step may be passed over to the schedule order step.
The RWH subsystem 1400 differentiates between two decisions: make or skip. These decisions are based on the calculation routine of the different planning method and make quantity calculations: The decision to make or skip the product is therefore based on the netting result different methods for calculating the make quantity per planning method. Two main concepts can be distinguished, bucket and rolling netting. The Project Inventory (PI) may be calculated by netting all receipts & demands from the past until the netting end time
For Net Bucket the demand horizon end time is the:
In the short term horizon the x-line can be set in the RWD subsystem 1300, up to it the calculated demands will omit forecast shares. Furthermore it is required to make sure the actual production quantity is solely based on actual consumption. Therefore, the forecast share of the planned order quantity has to be set to zero at a line-specific number of days before start of production.
The Make Quantity calculation has two basic methods:
Fixed Order Processing
After each product, it will be checked if the newly calculated order(s) are overlapping with existing fixed orders from previous planning activities.
Short Term Planning
If specified, the heuristic will reschedule fixed orders in the short-term horizon to optimize the OOE of the resource. Otherwise, it will schedule around the fixed orders by recalculating the dynamic setup times
Mid- and Long-Term Planning
In the long-term planning, fixed orders will be scheduled by recalculating the dynamic setup times. This can lead to gaps in the overall production plan, but is needed to avoid that fixed orders are continuously preponed by every planning run with the effect that the receipt time is much earlier than the demand time.
Wheel Cycle Time.
Factoring is necessary if the actual required total cycle length of the created production schedule exceeds or falls below the predefined maximum or minimum cycle length. As illustrated in
When applying lower factoring, idle times are added in order to lengthen the production cycle time. The idle time can be used for maintenance, training, continuous improvement or other activities that are frequently required.
Lower factoring or Minimum Cycle Time Factoring
Upper Factoring or Maximum Cycle Time Factoring
Possible factoring is overruled by some exception rules: factoring can only be applied to vendor-managed inventory (VMI) products; Make to Order (MTO) products and fixed orders must be excluded from factoring. If products are MTO the production quantity and due dates must coincide with the order quantity and date to deliver on time in full (OTIF). A high degree of VMI products is therefore desirable for the production site in order to flexibly apply factoring as required. Furthermore, lot size rules and minimum make quantities must be taken into account
Customized Factoring
After all make and skip decisions are made, the overall cycle time may be calculated. In the case that it is longer than the defined maximum cycle time, various factoring methods can be used sequentially to reduce the overall cycle time.
If the cycle time of a wheel is below the minimum cycle time the heuristic will automatically postpone the next cycle to ensure the minimum cycle time is kept. This will result in idle time on the resource.
If the cycle time exceeds the maximum cycle time after scheduling the orders, a default factoring method will be applied. This method will de-allocate all orders of this cycle starting after the calculated maximum end cycle time.
To provide the necessary information for the RWM subsystem 1600, the used RW design and the orders of the cycle are written to the Rhythm Wheel Log 1418.
In the schedule orders step, all products with a make decision will be scheduled in the sequence of the RW Design. For all short-term planning cycles, the heuristic checks if there will be a gap due to fixed orders. The gaps may be closed or rescheduled to start directly after the predecessor order.
Adjustments within Rhythm Wheel Heuristic
The RWH subsystem 1400 may consider the pre-configured SCM parameters, including stock parameters and the production-related Rhythm Wheel design parameters, as well as actual consumption to follow a pull-based SCM operating model. Furthermore, additional production characteristics are considered. For instance, if technical constraints require adherence to fixed lot sizes, production quantities need to be rounded up to multiples of such lot sizes.
Planning and scheduling with Rhythm Wheels is generally based on the replenishment signals provided by the replenishment trigger report. Following the report's make-or-skip decisions and replenishment quantities, planned orders for the upcoming Rhythm Wheel cycles are scheduled according to the predefined Rhythm Wheel sequence from the RWD subsystem 1400.
Below are example main methods with pseudo code of the RWH subsystem 1400 and include methods which have a direct impact to cycle calculation. Input and Output parameters are in Italic letters
Schedule all Cycles
Factoring
Methods for Make Quantity
Net Rolling MMQ
Net Bucket Null
Net Rolling Null
Methods for Default Factoring
De-Allocate
Customized Factoring Methods
Percentage
Cut Off
Fill Up Percentage
Fill Up Adhere to Min
Recalculate_Cycle_Times
Rhythm Wheel Log (RWL)
The Rhythm Wheel Log includes five tables created belonging to a single Rhythm Wheel planning run. All the relevant planning data of a run is logged within these tables. The different tables are merged by a table called/CLS/RWL_VIEW.
As soon as the RWH subsystem 1400 has executed, the RWL subsystem 1500 may execute. The RWL subsystem 1500 is used to the production plan, the used Design, the detailed information for each cycle, order/lot created during the heuristic run. RWL subsystem 1500 may also include all factoring events which are executed during the pre-calculation or at the end of a cycle.
This information is handed over/made available to the RWM subsystem 1600 by the RWL Log Adapter 1506. Furthermore, this information can be used for integration with other systems, such as:
As shown in relation to
As shown in relation to
As shown in relation to
As shown in relation to
Rhythm Wheel Monitor (RWM)
RWM subsystem 1600 is a tool to control and evaluate the Rhythm Wheel design and the Rhythm Wheel behavior. RWM subsystem 1600 is configured to display and compare the information from the design phase and the results from the RWH subsystem 1400. This ensures an evaluation of the (pre-)designed Rhythm Wheel design as well as continues improvement of the Rhythm Wheel based production. Furthermore the RWM subsystem 1600 may support the planner to analyze and understand the planning results of the Rhythm Wheel Heuristic.
The RWM subsystem 1600 may include an entry screen and four different views for each heuristic run:
The user is able to select a Rhythm Wheel range by filtering according to specific selection criteria, shown in input area 902. The number of eligible wheels may be reduced according to the entered selection criteria. The offered selection criteria of input area 902 may include:
After selecting one relevant Wheel, the aggregated view screen is entered, as illustrated in
As illustrated in
Furthermore, the average KPIs of the current Rhythm Wheel Heuristic run may be displayed. The KPIs are calculated without the use of any factoring methods as well as KPIs when factoring methods are applied. The calculation of the average KPIs resulting from the RWH subsystem 1500 is illustrated in
In order to measure the quality of a Rhythm Wheel design, the RWM subsystem 1600 may compare the designed Rhythm Wheel with the one that is ultimately scheduled. Therefore, performance KPIs are calculated and displayed by the RWM subsystem 1600. The corresponding formulas and description are illustrated in
The CTA may be computed as the ratio of average cycle time to planned cycle time. The time needed to complete each Rhythm Wheel cycle is measured from the start of the run of the first product in the Rhythm Wheel sequence to the start of the run of the same product in the next cycle. If there is no demand for this specific product, the time is measured from or to the run of the next product in the Rhythm Wheel sequence. The CTA metric tracks the cycle length over time and evaluates the difference between planned and actual cycle time. It shows how consistently an asset runs according to the designed Rhythm Wheel time and is thus a crucial metric for maintaining synchronization within the end-to-end supply network. Sustainable synchronization is possible only if all supply chain stages or assets adhere to the designed tact. The CTA is computed as the ratio of average cycle time to planned cycle time. The cycle times for consecutive Rhythm Wheel cycles are typically visualized on a process behavior chart, as illustrated in
Cycles that are too short are often just as bad as cycles that are too long. Every deviation from the planned production cycle reduces stability and predictability and increases nervousness along the supply chain Therefore, it may be important to monitor rhythm times constantly to be able to identify changes on the demand or supply side as early as possible. If the cycle times are, for example, longer than designed, a variety of potential causes on both the demand and the supply sides could be responsible. The overall demand at the asset might have been higher than expected, perhaps due to demand peaks for some products, or process lead times might have been excessive, perhaps due to unexpectedly long changeover times or low productivity. If deeper analysis shows that the long cycle times have not resulted from short-term events but are rather the product of future trends. An adjustment of the planned cycle time and the cycle time boundaries is required and should be considered in the next iteration of the tactical renewal process.
As illustrated in
Transparency regarding the behavior of cycle times is important for determining the optimal amount of safety stock that has to be held to cover variability of both demand and supply. If no agility stock process is in place as a general principle, it is recommended orienting the safety stock toward the longest cycle time measured in order to mitigate the risk of stock-outs due to extraordinarily long production cycles. Moreover, the cycle time boundaries should be set in accordance with fluctuations of the cycle time. The greater the cycle time variation, the less strictly should the cycle time boundaries be set. Thus, existing variability is at least partly buffered at the asset rather than being buffered entirely in inventories. Experience shows that the CTV depends heavily on the heterogeneity of the product portfolio at the asset. The more heterogeneous the mix is, the higher the cycle time variation typically will be. The allowed ranges need to be defined accordingly on a case-by-case basis. Generally, too much variation can be the consequence of higher-than-expected demand variability, unbalanced production rhythms, or cycle time boundaries that are too lax.
As illustrated in
As illustrated in
Additionally on the left side of the screen, the KPIs from the wheel design are shown to enable a direct comparison of the designed cycle KPIs and the actual ones.
The input data may be extracted from the Rhythm Wheel Log 1418, e.g., production and changeover time. The idle time is calculated with the help of the Log as well as resource shift data from the resource adapter.
The LEAN Suite implements certain lean planning concepts (e.g., “Lean Supply Chain Planning: The New Supply Chain Management Paradigm for Process Industries to Master Today's Vuca World” by Dr. Josef Packowski, ISBN-13: 978-1482205336, incorporated by reference herein) in an integrated application.
Although the foregoing description has been described by reference to various examples, it is to be understood that modifications and alterations in the structure and arrangement of those examples may be achieved by those skilled in the art and that such modifications and alterations can be practiced in the spirit of the appended claims. The examples herein are merely illustrative and are not meant to be an exhaustive list of all possible designs, examples or modifications of the disclosure.
This application claims benefit and priority to U.S. Provisional Application No. 62/149,231 filed Apr. 17, 2015, the disclosure of which is incorporated by reference herein in its entirety.
Number | Date | Country | |
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62149231 | Apr 2015 | US |
Number | Date | Country | |
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Parent | 16783722 | Feb 2020 | US |
Child | 17196881 | US | |
Parent | 15098606 | Apr 2016 | US |
Child | 16783722 | US |