Abstract:
A computerized automated demand-based parts delivery management system and method is disclosed. Parts for use in a production facility are received at a warehouse and housed in storage inventory areas such as trailers parked in a yard. Data about the parts in storage inventory areas and their locations as well as an inventory of parts in the warehouse are stored in a database. A “demand pegging” operation is performed by viewing current delivery inventory levels within the warehouse and applying them to production demand data to determine when parts will be depleted from delivery inventory areas. The operation further identifies storage inventory areas that have the needed parts. Process times for transporting parts between locations are considered in determining task times for transporting parts from storage inventory areas to delivery inventory areas so parts are replenished in advance of the deplete time determined by the demand pegging operation.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 12/240,852, filed Sep. 29, 2008, and titled SYNCHRONOUS AND OPTIMUM LINE DELIVERY UTILIZING TACT INFORMATION, which is incorporated herein by reference. This application claims priority to U.S. Provisional Patent Application No. 61/101,102, filed Sep. 29, 2008, titled LOGISTICS PROVIDER PARTS DELIVERY AND MANAGEMENT SYSTEM, which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to parts delivery management for assembly plants. More particularly, a computerized system and method is disclosed for automated demand-based parts delivery in which parts are pulled from an inventory holding area according to a production demand schedule. 
     BACKGROUND OF THE INVENTION 
     To keep production lines moving, manufacturers require delivery of the right part to the right place at the right time and in the right quantity. In conventional production lines such as automotive assembly lines, parts are added or assembled to a partially assembled product as it passes by assembly stations or areas on the production line. Associates working on the production line install parts and complete assembly processes as may be required to build a product meeting a particular set of specifications. A production schedule usually determines which manufacturer products will be built on a particular day or other production period and therefore, dictates which parts or components are needed on the production line so associates can complete the installation and assembly tasks at the assembly stations or areas. If an associate at an assembly station does not have the right parts at the right time, accommodations to the production process must be made. The product may be held or diverted to another location while attempts are made to locate the appropriate parts. Production slows or worse, may be halted entirely, as time is spent locating the appropriate part or parts to complete the necessary installation and assembly tasks. 
     To facilitate delivery of parts to the production line, some manufacturers work with a logistics provider that manages inventories of parts at the manufacturing facility and uses a variety of delivery techniques transport parts from various inventory locations to production line locations when a need for replenishment is determined. For example, when the line side supply of a particular part at a particular location drops below a threshold, a replenishment method may be used in which an associate drives a vehicle loaded with the low inventory part to the particular production line location. Other manufacturers respond to replenishment requests using automated guided vehicles that deliver parts to assembly line locations based on directional information programmed into the vehicles. 
     Various right part, right place, right time (RPT) production methods have been developed to reduce costs attributable to maintaining replenishment inventories. RPT techniques involve coordinating the delivery of parts to the manufacturer&#39;s assembly plant as well as to “line side” locations in an effort to reduce inventory levels and, consequently, costs. Some manufacturers have incorporated parts consolidation centers into their RPT practices. Consolidation centers are facilities where parts are received from suppliers, staged for use in one or more assembly plants (i.e., organized according to the order in which they will be consumed), and then transported from the consolidation center to an assembly plant production line where they are consumed. In an effort to control costs, suppliers may be asked to deliver parts to the consolidation center in conjunction with the manufacturer&#39;s production schedule and to provide parts in full truck loads rather than partial truck loads. 
     Although delivering parts in full truck loads is more cost-effective than delivering them in partial truck loads, it also impacts consolidation center or warehouse logistics. More time and effort is required to unload a full loaded trailer than a partially loaded trailer. In addition, the consolidation center or warehouse must be able to at least temporarily store and track the parts that are unloaded but are not ready to be delivered line side. While a manufacturer may arrange to have parts delivered from suppliers to the consolidation center or warehouse according to specific production needs, the arrival of the trucks that deliver the trailers of parts may not necessarily coincide with the manufacturer&#39;s schedule. If a substantial number of trailers are used to supply parts for production, the logistics provider that operates the consolidation center or warehouse must have procedures in place for receiving the trailers and determining how and when they will be unloaded. 
     Ideally, the unloading of trailers corresponds to the manufacturer&#39;s production needs and therefore, the need for parts. Determining which trailers are needed and when, however, requires an analysis of production requirements and inventory as well as knowledge about the parts inventory that is available on the trailers at the consolidation center. Information needed for such an analysis is often stored in different computerized systems and the applications executing at the computerized systems do not support such an analysis. What is needed is an application that provides an integrated view of the data and that analyzes the data to determine a schedule for unloading parts from trailers. There is a need for a computerized system and method for parts delivery that aligns the process of unloading trailers with a manufacturer&#39;s production needs. There is also a need for a computerized system and method for parts delivery that defines a schedule for unloading trailers consistent with a manufacturer&#39;s production needs. There is a need for a computerized system and method for parts delivery that accounts for a manufacturer&#39;s demand for parts throughout a production period. There is a need for a computerized parts delivery management system and method that correlates the unloading of trailers with a production schedule to further the goal of delivering the right part to the right production line location at the right time. 
     SUMMARY OF THE INVENTION 
     A computerized demand-based parts delivery management system and method furthers a logistics provider&#39;s goal of delivering the right part to the right production line location at the right time. In an example embodiment, a consolidation center for receiving parts from suppliers is co-located with an assembly plant. Parts are received in trailers that are parked in a yard at the consolidation center. Data about the parts on each trailer and each trailer&#39;s location in the yard is stored in a database. Other databases that are used in the computerized system and method store inventory data regarding parts available at the consolidation center as well as production demand data identifying the parts that are needed for production. The computerized system and method analyzes the inventory and production demand data to determine when parts from the trailers are needed to meet production demand. The trailers or other storage inventory areas that have the required parts are identified and a schedule for transporting parts from storage inventory areas (e.g., trailers) with the required parts is generated. The computerized system and method generates a receiving schedule that comprises a series of tasks for transporting trailers from the yard (or other storage inventory areas) to docks at the consolidation center. Yard drivers receive the task data and transport trailers to the docks according to the schedule. 
     The computerized system and method performs a “demand pegging” operation by viewing current inventory levels within the consolidation center and comparing them to production demand data. Production demand data is reflected in an order generation database that provides task data to associates of the logistics provider to load containers of parts on vehicles for delivery to the production line. For each task, the pick time and quantity of parts needed is known. The computerized system and method uses the pick time and quantity data to determine when part shortages are expected to occur and then to ensure that parts are unloaded from trailers or other containers to replenish inventory according to the time and quantity demand. Process time data related to the time required to transport parts between various locations is determined and used in calculating a time when a trailer from the yard or other container from a storage inventory area should be requested. As a result, a continuous supply of parts is made available to the associates that facilitate delivery of parts from the consolidation center to the production line. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of a consolidation center inventory and delivery process for an example embodiment; 
         FIGS. 2A-2D  are diagrams illustrating a demand pegging calculation for an example embodiment; 
         FIGS. 3A-3C  are diagrams illustrating a second demand pegging operation for an example embodiment; 
         FIG. 4  illustrates additional steps in a demand pegging operation for an example embodiment; and 
         FIG. 5  illustrates the final step in the demand pegging operation for an example embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , a block diagram of a consolidation center inventory and delivery process for an example embodiment is shown. One or more computer systems  100  may support the inventory and delivery process. A warehouse management system  102  tracks data related to the movement of parts throughout the consolidation center as follows: 
     
       
         
               
             
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Warehouse Management System Data 
               
             
          
           
               
                 Process 
                 Description 
               
               
                   
               
               
                 Inbound 
                 Parts arrive (in containers) on inbound trailers. WMS  
               
               
                   
                 102 has data for each inbound trailer and the parts  
               
               
                   
                 loaded in the trailer. 
               
               
                 Arrival and 
                 Trailers are processed through an arrival and  
               
               
                 Departure 
                 departure center. 
               
               
                 Center 
                   
               
               
                 Yard 
                 Trailers with parts are temporarily stored in the yard.  
               
               
                   
                 Each trailer is assigned a location in the yard and  
               
               
                   
                 each trailer&#39;s location in the yard is recorded in  
               
               
                   
                 WMS 102. 
               
               
                 QC, Small Lot, 
                 Special handling for parts. Certain parts may be  
               
               
                 Demand 
                 inspected or re-packed. 
               
               
                 Repack and Re- 
                   
               
               
                 pack 
                   
               
               
                 Putaway 
                 Containers of parts are stored in delivery inventory  
               
               
                   
                 areas at the consolidation center to facilitate a  
               
               
                   
                 pick/pack operation. Each container&#39;s location in the  
               
               
                   
                 consolidation center is recorded in WMS 102. The  
               
               
                   
                 containers are in an area available to associates  
               
               
                   
                 completing the pick/pack operations. 
               
               
                 Pick/Pack 
                 Containers are selected or “picked” from delivery  
               
               
                   
                 inventory or putaway locations for delivery to the  
               
               
                   
                 production line. Associates use a computer generated  
               
               
                   
                 “pick/pack” check sheets that identifies the part  
               
               
                   
                 containers to load on a cart by or at a specified time.  
               
               
                   
                 Containers may be loaded on multi-shelf carts that  
               
               
                   
                 are connected to form a train pulled by a tugger to  
               
               
                   
                 the production line. 
               
               
                 AF-On 
                 Parts are delivered line side and then used in  
               
               
                   
                 assembly operations during the production period. 
               
               
                   
               
             
          
         
       
     
     A delivery management system  104  tracks data related to the transportation of parts from the consolidation center to the production line as follows: 
     
       
         
               
             
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Delivery Management System 
               
             
          
           
               
                 Process 
                 Description 
               
               
                   
               
               
                 Train Building 
                 Trains comprising a plurality of cart types are assembled  
               
               
                   
                 throughout the production period and loaded with parts  
               
               
                   
                 containers that are delivered line side. Trains are 
               
               
                   
                 reconfigured throughout the production period and parts  
               
               
                   
                 are delivered when needed to the appropriate production  
               
               
                   
                 line locations. The delivery management system 104 
               
               
                   
                 receives manufacturer production schedule data as well as  
               
               
                   
                 part and container data to determine which parts are needed  
               
               
                   
                 and when they are needed. Lead times for delivering parts  
               
               
                   
                 to different line side locations are determined and used in  
               
               
                   
                 configuring carts for each train that transports the parts. 
               
               
                 Pick/Pack 
                 Containers are selected or “picked” for delivery to the  
               
               
                   
                 production line. Associates use a “pick/pack” check sheets  
               
               
                   
                 that identifies the part containers to load on a cart by or at  
               
               
                   
                 a specified time. Containers may be loaded on multi-shelf  
               
               
                   
                 carts that are connected to form a train that is pulled by a  
               
               
                   
                 tugger to the production line. 
               
               
                 Staging 
                 Organize carts and trains for delivery of parts to production  
               
               
                   
                 line side locations. 
               
               
                 Deliver 
                 Tuggers pull multi-cart trains to specified production line  
               
               
                   
                 locations identified on the parts containers. 
               
               
                 ADN 
                 Parts are delivered line side throughout the production  
               
               
                   
                 period. 
               
               
                   
               
             
          
         
       
     
     Process times for transporting parts from the yard to the consolidation center as well as between points in the consolidation center and to the production line locations are considered in determining task times  106 . In an example embodiment of demand pegging, trailers in the yard are “pegged” and transported from the yard to the consolidation center approximately six to seven hours in advance of the time that the parts on the trailer are required line side. The interval between “pegging” and line side delivery provides sufficient time to move trailers and unload them in time to replenish delivery inventory at putaway locations where the parts are selected or “picked” for delivery to production line locations. 
     Data from several sources is used to determine task times for pulling and unloading trailers. An inventory database  108  comprises location and quantity data  112  for the parts  110  used in production. In the example shown, 120 units of part 12345-SH3-A000: NH167L each are in trailers  101  and  321  in the yard and in putaway location A101 for a total of 360 units in consolidation center inventory. An order generation database  114  comprises pick/pack time and demand data  116  for the parts used in production. The pick/pack time and demand data  116  identifies when the specified quantity of parts should be “picked” from the consolidation center delivery inventory in putaway locations for delivery to the production line. In the example shown, 30 units of the part are picked for delivery every half hour from 8:00 to 10:30 and again from 2:00 to 3:00. Finally, process time data from a process time or “time to complete table” database  118  is used to determine task times for transporting trailers from the yard to docks at the consolidation center. A process time for transporting parts between various locations in the consolidation center is calculated and recorded in the process time database. For each pair of locations, a complete time is determined and based on the complete time, a start time is determined. For example, the complete process time between the “from” locations “putaway” and “to” location “staging” is 120 minutes  122 . The assigned start time is 180 minutes before the time the parts are needed at the ending or “to” location. For the “from” location “small lot” to the “to” location “putaway,” the complete process time is 90 minutes while the assigned start time is 120 minutes before the time the parts are needed at the “putaway” location  124 . 
     Referring to  FIGS. 2A-2D , diagrams illustrating a demand pegging calculation for an example embodiment are shown. Referring to  FIG. 2A , in the first phase of the demand pegging calculation, the changes in inventory levels that occur as each order generation task is completed are calculated. The calculations are used to generate work tasks against the specific demand. The order generation database  114  comprises pick/pack time data and demand data  116  for a specified part  110  (e.g., part no. 12345-SH3-A0000 NH167L). The inventory database  108  indicates that for the specified part  110 , 120 units are in “putaway” location A101, 120 units are in yard—trailer  321 , and 120 units are in yard—trailer  101   112 . 
     The demand pegging calculations are performed using a demand pegging work file  130 . A demand pegging table  132  comprising time and demand data from the order generation database  114  as well as putaway, receiving, and yard inventory data from the inventory database  108  is maintained in the demand pegging work file database  130 . The time and demand data  134  is obtained from the order generation database  114  and the putaway and yard inventory data  134  is obtained from the inventory database  108 . As pick/pack and demand data is added to the demand pegging table  132  for each order generation task, the resulting changes in inventory are tracked. Initially, delivery inventory from the putaway location is tracked. For example, when the 8:00 pick/pack task for 30 units of the part is completed, the starting delivery (putaway) inventory of 120 units is reduced to 90 units  134 . Based on the inventory tracking calculations  132 , the system “pegs” the time needed for the unloading trailers and generates a task list  138  that is stored in a WMS task database  136 . 
     A WMS task database  136  comprises the task list  138  related to the part  110  and the movement or flow of various quantities of the part throughout the consolidation center. The task list  138  comprises a description of the task and the time it should be completed as well as the pick/pack time (8:00 AM) and demand data (30 units) obtained from the order generation database  114 . The demand for parts as indicated in the order generation database is used to populate the task list with specific tasks related to the part. 
     Referring to  FIG. 2B , additional entries from the order generation database  114  are copied to the demand pegging table  132  in the demand pegging work file  130  and to the task list  138  in the WMS task database  136 . As each entry from the order generation table  116  is added to the demand pegging table  132 , the units that will be consumed as the processes are completed are deducted from the inventory data (delivery/putaway, receiving, and yard) in the table. Initially, the units are deducted from the delivery inventory in a putaway location. In the example shown, the delivery (putaway) inventory is 120 units at 7:45, 90 units at 8:00, 60 units at 8:30, 30 units at 9:00, 0 units at 9:30 and −30 units at 10:00. As a result of the calculations, a deplete time of 10:00 is determined. Although the deplete time for the example calculation is associated with the time at which the inventory level is negative, one of skill in the art would recognize that the deplete time may be any time at which it is determined the inventory level is insufficient to meet the production demand. Similar calculations may be performed based on when the number of units is at zero rather than below zero. 
     When the delivery inventory level in putaway location becomes negative or is depleted, a trailer in the yard with the specified part is “pegged” for unloading. Referring to  FIG. 2C , additional details regarding the pegging process are shown. Calculations from the demand pegging table indicate that delivery inventory in the putaway location will drop below zero units for the 10:00 pick/pack task  140  if the inventory is not replenished. When the inventory for the part  110  drops below zero, the demand pegging operation checks the available inventory in the trailers to identify a trailer for unloading. In the example, yard trailer  101  has 120 units  142  of the part  110  that is needed. An entry in the process or “time to complete” database  118  indicates that the process of transporting a trailer from the yard to a consolidation center dock and unloading it requires 90 minutes to complete  144 . The start time is 120 minutes before the time at which the need is identified (10:00) 144. The time to complete the task is 90 minutes  144 . A task of pulling trailer  101  at 8:00 (120 minutes before the parts are needed at 10:00) and unloading it by 9:30 (90 minutes after the start time) is generated and added to the task list  146 . Finally, the number of parts ( 120 ) associated with the task is added to the task list  138 . 
     Referring to  FIG. 2D , the process of updating the demand pegging table  132  and task list  128  is illustrated. The 8:00 pull trailer entry  146  from the task list  138  is used to update entries in the demand pegging table  154  so that additional demand-based tasks can be generated. The 8:00 “pull trailer  101 ” task  146  which involves 120 units results in a corresponding decrease of 120 units in the yard inventory and an increase of 120 units in the receiving inventory for the 8:00 entry  150 . At 9:30 when the unloading task is complete (e.g., parts transported from dock to putaway location), the receiving inventory is decreased by 120 units and the delivery inventory in the putaway location is increased by 120 units  152 . The parts from trailer  101  are then available for the 10:00 pick/pack task  140  and the 10:00 pick/pack task is added to the task list  156 . 
     Referring to  FIGS. 3A-3C , diagrams illustrating a second demand pegging operation for an example embodiment are shown. Referring to  FIG. 3A , a 10:30 pick/pack entry originating from the order generation database  114  is added to the demand pegging work table  160  and to the task list  164 . Additional entries for 2:00 and 2:30 are also added to the demand pegging work table  160  and to the task list  164 . For each entry in the demand pegging work table  160 , the delivery inventory level in the putaway location is assigned to the pick/pack task until the inventory becomes negative. At 15:00, the delivery inventory level in the putaway location once again drops below zero  160 . 
     Referring to  FIG. 3B , the negative entry in the demand pegging work table  160  results in the demand pegging operation of locating a trailer with the needed parts. The inventory database  108  indicates that yard—trailer  321  has 120 units of the specified part 12345-SH3-A000  110 . The process time database  118  indicates that the process of transporting a trailer from the yard to a consolidation center dock and unloading it requires 90 minutes to complete  144 . The start time is 120 minutes before the time at which the need is identified (10:00)  144 . The time to complete the task is 90 minutes  144 . A task of pulling trailer  321  at 13:00 (120 minutes before the parts are needed at 15:00) and unloading it by 14:30 (90 minutes after the start time) is generated and added to the task list  172 . Finally, the number of parts  120  associated with the task is added to the entry  172  in task list  138 . 
     Referring to  FIG. 3C , the process of updating the demand pegging table  132  and task list  128  is illustrated. The 13:00 pull trailer entry  172  from the task list  138  is used to update entries in the demand pegging table  132  so that additional demand-based tasks can be generated. The 13:00 “pull trailer  321 ” task  172  which involves 120 units results in a corresponding decrease of 120 units in the yard inventory and an increase of 120 units in the receiving inventory for the 13:00 entry  182 . At 14:30 when the unloading task is complete, the receiving inventory is decreased by 120 units and the delivery inventory in the putaway location is increased by 120 units  184 . The parts from trailer  321  are then available for the 15:00 pick/pack task  160 . The 15:00 pick/pack task is then added to a new entry  180  in the task list  138 . 
     Referring to the  FIG. 4 , additional steps in the demand pegging operation include sorting the task list based on start time  190  after all items in the order generation table  116  have been processed. In the example, the demand pegging operation resulted in two “pull trailer” tasks that were generated and added to the task list. Trailer  101  is called at 8:00 while trailer  321  is called at 13:00. The trailers are unloaded and the delivery inventory in putaway locations is replenished at the appropriate times so that the pick/pack operations can continue. 
     Referring to  FIG. 5 , the final step in the demand pegging operation is to add task numbers  200  to entries in the task list  138 . The task numbers allow individual tasks to be tracked for various reasons. Trailer pull tasks for a plurality of parts may be added to a receiving schedule that is provided to associates responsible for transporting trailers from the yard to docks at the consolidation center. The receiving schedule provides associates with information regarding the order in which trailers are requested and therefore, unloaded at the consolidation center. An example receiving schedule is shown in Table 3: 
     
       
         
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 Sample Receiving Schedule 
               
             
          
           
               
                 L/D 
                 Trailer 
                 Date 
                 Time 
                 SCAC 
                 Trailer 
                 Dock 
                 Door 
               
               
                   
               
               
                 D 
                 Inb-Door 
                 Jun. 24, 2009 
                 09:47 
                 CHBL 
                 9722 
                 C1 
                 018 
               
               
                 D 
                 Inb-Door 
                 Jun. 24, 2009 
                 11:34 
                 ONEW 
                 3256 
                 C1 
                 018 
               
               
                 D 
                 Inb-OnYar 
                 Jun. 24, 2009 
                 11:57 
                 BSYS 
                 50022  
                   
                   
               
               
                 D 
                 Inb-Door 
                 Jun. 24, 2009 
                 12:44 
                 CUOT 
                 9854 
                 C1 
                 026 
               
               
                 D 
                 Inb-OnYar 
                 Jun. 24, 2009 
                 14:18 
                 CHBL 
                 2323 
                   
                   
               
               
                 D 
                 Inb-OnYar 
                 Jun. 25, 2009 
                 08:22 
                 AVRT 
                 1270 
                   
                   
               
               
                 D 
                 Inb-OnYar 
                 Jun. 25, 2009 
                 08:22 
                 BLQO 
                 5253 
                   
                   
               
               
                 D 
                 Inb-OnYar 
                 Jun. 25, 2009 
                 08:49 
                 CH BL 
                 2323 
                   
                   
               
               
                 D 
                 Inb-OnYar 
                 Jun. 25, 2009 
                 09:25 
                 CKTF 
                 1010 
                   
                   
               
               
                 D 
                 Inb-OnYar 
                 Jun. 25, 2009 
                 12:11 
                 CUOT 
                 3003 
                   
                   
               
               
                 D 
                 Inb-OnYar 
                 Jun. 25, 2009 
                 13:13 
                 BSYS 
                 5006 
               
               
                   
               
             
          
         
       
     
     Although a trailer may be pegged because of a particular part that is loaded on the trailer, the trailer may additionally have parts that are not subject to the demand pegging request. The entire trailer may be unloaded and parts that were not subject to the demand pegging request may be added to the consolidation center inventory and used to fulfill production demand. Any type of container for storing parts may be subject to a demand pegging operation and containers may be stored in various types of storage inventory areas (e.g., trailers in a yard). Each container may comprise different types of parts in addition to the type of part that is subject to a demand pegging request. 
     The demand pegging function is applied to all parts in the order generation database  114  so that parts flow to the delivery inventory in putaway locations as needed to meet the manufacturer&#39;s production demand. Using the demand pegging function, inventory for production may be held in trailers in the yard and called on demand. The demand pegging operation allows the logistics provider to prioritize the unloading of trailers. Although trailers may arrive at the yard in any order, the demand pegging operation defines an order for unloading them by considering production demands. Trailers are “pegged” according to the parts they contain so that a flow of parts to production is maintained. 
     Although the demand pegging operation is described in relation to a consolidation center inventory that is maintained in a trailer yard, the operation may be applied to inventory maintained in other areas of the consolidation center. For example, inventory maintained in an overstock area or areas maintained off site may be pegged. The computerized system and method may be configured in a variety of ways to meet the needs of the logistics provider including the manner in which inventory areas are defined and managed. Some locations may be managed as delivery inventory areas in which parts are held for the pick/pack operation while other areas are primarily short-term storage areas (e.g., yard, overstock). 
     An exemplary embodiment of a computerized parts delivery management system has been shown and described above. It should be realized by one skilled in the art that various modifications may be made to the computerized system and method described above as well as data items and databases used in the analysis. Changes to the production phases and delivery techniques as well inventory locations may be made and fall within the scope of the claimed invention. Therefore, while certain embodiments of the present invention are described in detail above, the scope of the invention is not to be considered limited by such disclosure, and modifications are possible without departing from the spirit of the invention as evidenced by the following claims: