外文翻譯--關(guān)于自動(dòng)化立體倉(cāng)庫(kù)使用雙貨叉的探討

1、<p><b>　　附錄A </b></p><p><b>　　英文原文</b></p><p>　　An Analysis of Dual Shuttle Automated</p><p>　　Storage/Retrieval Systems</p><p>　　An Analys

2、is of Dual Shuttle</p><p>　　Automated Storage/Retrieval Systems </p><p>　　Adhinarayan Keserla</p><p>　　Brett A. Peters </p><p><b>　　Abstract:</b></p>

3、<p>　　This paper addresses the throughput improvement possible with the use of a dual shuttle automated storage and retrieval system. With the use of such a system, travel between time in a dual command cycle is vi

4、rtually eliminated resulting in a large throughput improvement. The dual shuttle system is then extended to perform an equivalent of two dual commands in one cycle in a quadruple command mode (QC). A heuristic that seque

5、nces retrievals to minimize travel time in QC mode is developed. Monte C</p><p>　　Key words:</p><p>　　Automated Storage/Retrieval Systems Design; Automated Storage/Retrieval Systems Operation; M

6、aterial Handling Systems; Performance Modeling and Analysis </p><p>　　Introduction:</p><p>　　Automated storage/retrieval systems (AS/RS) are widely used in warehousing and manufacturing applicat

7、ions. A typical unit load AS/RS consists of storage racks, S/R machines, link conveyors, and input/output (I/O) stations. An important system performance measure is the throughput capacity of the system. The throughput c

8、apacity for a single aisle is the inverse of the mean transaction time, which is the expected amount of time required for the S/R machine to store and/or retrieve a unit load. The</p><p>　　Han et al. [2] imp

9、roved the throughput capacity of the AS/RS through sequencing retrievals. Intelligently sequencing the retrievals can reduce unproductive travel between times when the S/R machine is traveling empty and thereby increase

10、the throughput. They develop an expression for the maximum possible improvement in throughput if travel between is eliminated for an AS/RS that is throughput bound and operates in dual command mode. In essence, this mean

11、s that if the S/R machine travels in a sin</p><p>　　In this paper, we analyze an alternative design of the S/R machine that has two shuttles instead of one as in a regular AS/RS. The new design eliminates th

12、e travel between the storage and retrieval points and performs both storage and retrieval at the point of retrieval, thereby achieving the maximum throughput increase calculated by Han et al. [3]. </p><p>　　

13、The dual shuttle AS/RS is a new design aimed at improving S/R machine performance. Most studies on AS/RS systems have been based on a single shuttle design. In our analysis of the dual shuttle AS/RS performance, we build

14、 upon these previous research results. </p><p>　　1 Alternative S/R Machine Design</p><p>　　A typical unit-load AS/RS has an S/R machine operating in each aisle of the system. The S/R machine has

15、 a mast which is supported at the floor and the ceiling and travels horizontally within the aisle. Connected to this mast is a shuttle mechanism that carries the unit load and moves vertically up and down the mast. The s

16、huttle mechanism also transfers loads in and out of storage locations in the rack. Figure 1 provides an illustration of the single shuttle S/R machine. </p><p>　　Figure 1. Single Shuttle S/R Machine Design &

17、lt;/p><p>　　A typical single shuttle AS/RS can perform a single command cycle or a dual command cycle. A single command cycle consists of either storage or retrieval. For storage, the time consists of the time

18、to pickup the load at the I/O point, travel to the storage point, deposit the load at that point, and return to the I/O point. The time for retrieval is developed similarly. </p><p>　　A dual command cycle in

19、volves both storage and retrieval in the same cycle. The cycle time involves the time to pickup the load at the I/O point, travel to the storage location, place the load in the rack, travel empty to the retrieval locatio

20、n, retrieve a load, return to the I/O point, and deposit the load at the I/O point. </p><p>　　If we critically analyze the dual command cycle of the S/R machine (shown by the solid line in Figure 2), a poten

21、tial open location for a future storage is created when a retrieval is performed. Furthermore, if both a retrieval and a storage are performed at the same point, the travel between time (TB) is eliminated, and the travel

22、 time will be equal to the single command travel time. With the existing AS/RS design, this mode of operation is not possible; therefore, an alternative to the S/R mac</p><p>　　Figure 2. Dual Command Travel

23、Paths of S/R and R/S Machines </p><p>　　2 R/S Machine Operations</p><p>　　Consider an S/R machine with two shuttle mechanisms instead of one. This new S/R machine could now carry two loads simul

24、taneously. Each shuttle mechanism could operate independently of the other, so that individual loads can still be stored and retrieved. An illustration of the dual shuttle S/R machine is shown in Figure 3. This new S/R m

25、achine would operate as described below. </p><p>　　Figure 3. Dual Shuttle S/R Machine Design </p><p>　　The S/R machine picks up the item to be stored from the I/O point, loads it into the first

26、shuttle, and moves to the retrieval location. After reaching the retrieval location, the second shuttle is positioned to pickup the item to be retrieved. After retrieval, the S/R machine positions the first shuttle and d

27、eposits the load. The S/R machine then returns to the I/O point. The operation can easily be seen as a single command operation plus a small travel time for repositioning the S/R machine be</p><p>　　Since th

28、e R/S machine has two shuttles, the position of the shuttles has a role in the operation of the system. With two shuttles, the R/S machine is able to perform a dual command cycle at one location in the rack. This operati

29、on is accomplished by first retrieving the load onto the empty shuttle, transferring the second shuttle into position, and storing the load into the empty location in the rack. However, the choice of shuttle configuratio

30、n does not impact the analysis in this paper. </p><p>　　To perform these operations, the R/S machine must move the second shuttle into position after the first shuttle has completed the retrieval. Due to the

31、 small distance involved, the R/S machine will use a slower creep speed for positioning, but this travel time is generally small. Furthermore, an amount of creep time is usually included in the pickup and deposit time to

32、 account for this required positioning. A second design characteristic is that additional clearance beyond the first and last row</p><p>　　3 Throughput Improvement</p><p>　　To estimate the throu

33、ghput improvement by the dual shuttle system over existing designs, we use the expressions for single command and dual command cycle times developed by Bozer and White [1] and the tabulated values for the nearest neighbo

34、r heuristic from Han et al. [4]. In developing the expressions, the authors in [1] and [4] made several assumptions. The same assumptions hold for the new design and include the following. </p><p>　　1 The ra

35、ck is considered to be a continuous rectangular pick face where the I/O point is located at the lower left-hand corner of the rack. </p><p>　　2 The rack length and height, as well as the S/R machine velocity

36、 in the horizontal and vertical directions, are known. </p><p>　　3 The S/R machine travels simultaneously in the horizontal and vertical directions. In calculating the travel time, constant velocities are us

37、ed for horizontal and vertical travel. Acceleration and deceleration effects are implicitly accounted for in either a reduced top speed or an increased pickup and deposit time. A creep speed is used for repositioning the

38、 dual shuttle. </p><p>　　4 Pickup and deposit times associated with load handling are assumed constant and, therefore, these could be easily added into the cycle time expressions. </p><p>　　5 Th

39、e S/R machine operates either on a single or dual command basis, i.e., multiple stops in the aisle are not allowed. (This assumption is later relaxed for the new R/S machine to perform a quadruple command cycle.) </p&

40、gt;<p>　　6 For the nearest neighbor heuristic, a block of n retrievals is available for sequencing and there are m initial open locations in the rack face. </p><p>　　4 Dual Shuttle S/R Systems</p&

41、gt;<p>　　The new design of the S/R machine has two shuttles and therefore could be operated as a dual shuttle system: carrying two loads and depositing them, retrieving two loads, and returning to the I/O point to

42、 deliver them as shown in Figure 4. The above operation can be performed by storing and retrieving the loads at four different locations. Therefore, the travel time would consist of the time for a single command travel p

43、lus three travel between times. To more efficiently perform the 4 operations</p><p>　　5 Conclusions</p><p>　　This paper performs an analysis of dual shuttle automated storage and retrieval syste

44、ms. Several contributions have been made including the following. </p><p>　　1 Throughput improvements in the range of 40-45% can be obtained using the quadruple command cycle relative to dual command cycles

45、with a single shuttle system. </p><p>　　2 With the dual shuttle design, travel between is virtually eliminated for a dual command cycle. </p><p>　　The dual shuttle system shows promise for situ

46、ations requiring high throughput. The main disadvantage with the new design is the extra cost of the S/R machine. An economic evaluation is needed to determine if it is appropriate for a particular situation. However, ba

47、sed on throughput performance, the dual shuttle design appears promising. </p><p>　　The concept of dual shuttle systems can also be extended to other material handling systems. Furthermore, research is neede

48、d to consider other storage strategies, such as class based storage policies, to examine their impact on throughput in conjunction with the dual shuttle design. This paper provides a framework for analyzing dual shuttle

49、AS/RS, and it provides a foundation for other material handling research related to this conc.</p><p><b>　　附錄B</b></p><p><b>　　中文譯文</b></p><p>　　關(guān)于自動(dòng)化立體倉(cāng)庫(kù)使用雙

50、貨叉的探討</p><p>　　Adhinarayan Keserla</p><p><b>　　布雷特 A. 彼得</b></p><p><b>　　摘 要:</b></p><p>　　本文主要探討的是可以提高生產(chǎn)效率的雙貨叉立體倉(cāng)庫(kù)系統(tǒng)。通過使用該系統(tǒng)，可以縮短堆垛機(jī)在一個(gè)雙任務(wù)流程中的

51、運(yùn)行時(shí)間，從而大大提高了倉(cāng)庫(kù)的工作效率。雙貨叉?zhèn)}庫(kù)系統(tǒng)相當(dāng)于一個(gè)四任務(wù)指令模塊（quadruple command mode簡(jiǎn)稱QC）中的雙指令任務(wù)書流程。一個(gè)很有建設(shè)性的思想被提出來(lái)，即通過堆垛機(jī)按某一順序運(yùn)行可以縮短在一個(gè)（QC）中的運(yùn)行時(shí)間，蒙地卡羅對(duì)此進(jìn)行了模擬對(duì)比實(shí)驗(yàn)，實(shí)驗(yàn)結(jié)果證明確實(shí)提高了堆垛機(jī)的搬運(yùn)效率，這就說明了這種方案的可行性。</p><p>　　關(guān)鍵詞:自動(dòng)化立體倉(cāng)庫(kù)； 自動(dòng)化立體倉(cāng)庫(kù)的控制

52、；功能模擬和分析</p><p><b>　　1 緒論</b></p><p>　　自動(dòng)化立體倉(cāng)庫(kù)被廣泛地應(yīng)用于倉(cāng)儲(chǔ)和制造設(shè)備當(dāng)中。典型的單位貨物裝卸立體倉(cāng)庫(kù)由儲(chǔ)藏架，堆垛機(jī)，自動(dòng)運(yùn)輸小車，和入庫(kù)/出庫(kù)臺(tái)組成。衡量一個(gè)立體倉(cāng)庫(kù)系統(tǒng)的優(yōu)劣的主要標(biāo)準(zhǔn)是倉(cāng)庫(kù)系統(tǒng)的工作效率。立體倉(cāng)庫(kù)的工作效率與堆垛機(jī)運(yùn)行一個(gè)工作流程所需的時(shí)間成反比，這個(gè)工作流程時(shí)間包括堆垛機(jī)裝卸貨物的時(shí)間，

53、顯然堆垛機(jī)裝卸貨物的時(shí)間在一定程度上取決于堆垛機(jī)和貨架的具體結(jié)構(gòu)和規(guī)格。</p><p>　　Han 通過立體倉(cāng)庫(kù)返回站點(diǎn)的排列提高了立體倉(cāng)庫(kù)的工作能力，合理的排列返回站點(diǎn)堆垛機(jī)能減少不必要的行程，從而縮短了時(shí)間，提高了效率。這樣他們就提出了一種最大限度提高效率理論，即如果堆垛機(jī)在雙指令模塊流程中可以縮短運(yùn)行時(shí)間那么這將最大程度的提高立體倉(cāng)庫(kù)的工作效率。也就是說，如果堆垛機(jī)運(yùn)行的是單命令路線，卻能完成存貨和返回的

54、動(dòng)作，則工作效率的提高也就實(shí)現(xiàn)了。</p><p>　　在論文中，我們分析了一種可供選擇的堆垛機(jī)設(shè)計(jì)方法，這種設(shè)計(jì)出來(lái)的堆垛機(jī)與一般的堆垛機(jī)不同，在原來(lái)的基礎(chǔ)增加了一個(gè)貨叉，這種新穎設(shè)計(jì)的堆垛機(jī)擁有兩個(gè)貨叉，它在運(yùn)作中可以縮短在貨架到返回點(diǎn)之間的運(yùn)行時(shí)間。這種設(shè)計(jì)方案符合 Han 所說的最大效率理論。</p><p>　　雙貨叉堆垛機(jī)主要是針對(duì)如何提高堆垛機(jī)的工作能力這一問題所設(shè)計(jì)的一種新

55、穎堆垛機(jī)。目前，立體倉(cāng)庫(kù)系統(tǒng)的研究是以單貨叉堆垛機(jī)為主要對(duì)象。在本文關(guān)于雙貨叉堆垛機(jī)功能的分析也是建立有前人研究的基礎(chǔ)上的。</p><p>　　2 可供選擇的堆垛機(jī)設(shè)計(jì)</p><p>　　一個(gè)基本的單一裝載立體倉(cāng)庫(kù)系統(tǒng)中，每一個(gè)貨架巷道內(nèi)都有一臺(tái)可供操作的堆垛機(jī)，每臺(tái)堆垛機(jī)有一根立柱被固定在天花板和地面之間，這根立柱可以在巷道內(nèi)的水平位置移動(dòng)。與立柱相連的是一個(gè)貨叉機(jī)構(gòu)，它可以載著貨物

56、沿著立柱上下移動(dòng)，貨叉也可以作相對(duì)于貨格的水平取貨和存貨運(yùn)動(dòng)。</p><p>　　一個(gè)基本的單貨叉堆垛機(jī)立體倉(cāng)庫(kù)系統(tǒng)能夠完成一個(gè)單指令作業(yè)流程也能完成一個(gè)雙指令作業(yè)流程。一個(gè)單指令作業(yè)流程由存貨和取貨組成，對(duì)于一個(gè)存貨過程所需時(shí)間包括堆垛機(jī)在入庫(kù)處裝載貨物，行駛到目標(biāo)貨格，卸下貨物，然后回到倉(cāng)庫(kù)入口處這一連串動(dòng)作總共所需的時(shí)間。同樣可以分析取貨過程所需時(shí)間。</p><p>　　一個(gè)雙指

57、令流程就是在同一個(gè)工作流程中完成存貨和取貨的操作。這個(gè)過程時(shí)間包括從入口處裝貨，運(yùn)行到存貨貨格位置，把貨放在貨架上，空運(yùn)行到取貨貨格位置，從貨架上取下貨物，回到倉(cāng)庫(kù)入口處，并卸下貨物這一過程總共需要的時(shí)間。</p><p>　　如果我們對(duì)堆垛機(jī)的雙指令工作流程路線稍加分析就會(huì)發(fā)現(xiàn)，當(dāng)在完成一個(gè)取貨運(yùn)作時(shí)，就暗示著可以進(jìn)行下一個(gè)存貨運(yùn)作，而且，如果在同一地方可以進(jìn)行存貨和取貨運(yùn)作，那么運(yùn)行時(shí)間將被縮短，這個(gè)運(yùn)行時(shí)間

58、相當(dāng)于運(yùn)行一個(gè)單指令流程所需的時(shí)間。就目前已存在的立體倉(cāng)庫(kù)設(shè)計(jì)，要實(shí)現(xiàn)這種操作是不可能的，因此，另外一種雙貨叉式的堆垛機(jī)就應(yīng)運(yùn)而生了。</p><p><b>　　3 堆垛機(jī)的運(yùn)作</b></p><p>　　設(shè)想一臺(tái)安裝了兩個(gè)貨叉的堆垛機(jī),這種新穎的堆垛機(jī)可以同時(shí)裝載兩件貨物,為了兩件貨物分別能存庫(kù)和出庫(kù),所以堆垛機(jī)的兩個(gè)貨叉機(jī)構(gòu)能夠相互獨(dú)立運(yùn)行,具體結(jié)構(gòu)如圖3所示

59、,這種堆垛機(jī)的工作過程將在下文詳細(xì)介紹。</p><p>　　堆垛機(jī)從倉(cāng)庫(kù)入口處將要被儲(chǔ)存的貨物裝載到第一個(gè)貨叉平臺(tái)上，然后向取貨的位置移動(dòng).到達(dá)要取貨的位置之后，第二個(gè)貨叉臺(tái)伸貨格內(nèi)取貨，當(dāng)取貨的動(dòng)作完成之后，堆垛機(jī)控制第一個(gè)貨叉臺(tái)卸貨。堆垛機(jī)然后再回到入口處。這整個(gè)操作流程就像是一個(gè)單指令運(yùn)作再加上一小段重新定位運(yùn)行過程（即堆垛機(jī)第二個(gè)貨叉平臺(tái)裝載和卸載過程），這樣一來(lái)，其運(yùn)作就像一臺(tái)堆垛機(jī)完成先完成取貨然后

60、再存貨的一個(gè)雙任務(wù)命令。</p><p>　　因?yàn)檫@種堆垛機(jī)有兩個(gè)貨叉平臺(tái)，所以兩個(gè)貨叉的定位控制將是系統(tǒng)的一個(gè)很重要的功能。堆垛機(jī)用兩個(gè)貨叉可以在某個(gè)貨架的同一位置完成一個(gè)存、取雙任務(wù)指令，先在空貨駐臺(tái)上取下要出庫(kù)的貨物，再移動(dòng)第二貨叉到指定位置把貨物放在空貨格內(nèi)。然而，貨叉平臺(tái)結(jié)構(gòu)的選擇與本文的討論內(nèi)容無(wú)關(guān)。</p><p>　　為了實(shí)現(xiàn)上述操作，堆垛機(jī)的第二個(gè)貨叉必須在第一個(gè)貨叉完成

61、取貨動(dòng)作之后才能進(jìn)行定位操作。由于貨叉的定位移動(dòng)量是較小的，堆垛機(jī)采用的是低速爬行方式來(lái)實(shí)現(xiàn)貨叉微小的定位移動(dòng)量，在這個(gè)過程中所耗費(fèi)的時(shí)間與堆垛機(jī)在裝貨卸貨耗費(fèi)的時(shí)間相比一般是微乎其微的。倉(cāng)庫(kù)設(shè)計(jì)的另外一個(gè)特點(diǎn)是第一排貨格和最后一排貨格的兩端要留有位置余量，以便在堆垛機(jī)超程時(shí)給兩個(gè)貨叉平臺(tái)留有運(yùn)動(dòng)余地。 </p><p><b>　　4 工作效率提高</b></p><p

62、>　　為了估算正在設(shè)計(jì)的雙貨叉系統(tǒng)工作量的提高，我們引用Bozer 和 White[1]提出的有關(guān)單任務(wù)和雙任務(wù)指令所需時(shí)間理論和Han et al.提出的最近有意義想法價(jià)值理論，這些理論家都作了種種設(shè)想，他們?cè)O(shè)想的共同部分就是我們要引用的內(nèi)容，下面就是這些理論的內(nèi)容。</p><p>　　1．倉(cāng)庫(kù)的貨架被考慮成為連續(xù)矩形框架，貨物出/入處被設(shè)置在貨格的左下角位置。</p><p>

63、　　2．貨架的長(zhǎng)度和寬度以及堆垛機(jī)水平和垂直運(yùn)行的速度應(yīng)該明確。</p><p>　　3．堆垛機(jī)貨叉臺(tái)能同時(shí)在水平和垂直兩個(gè)方向運(yùn)動(dòng)，在計(jì)算運(yùn)行時(shí)間方面作如下處理，貨叉在水平和垂直方向時(shí)進(jìn)行勻速運(yùn)動(dòng)，加速和減速緩沖極限速度，爬行速度用來(lái)定位兩個(gè)貨叉臺(tái)。</p><p>　　4．假設(shè)與物流過程相關(guān)的裝載貨物和卸載貨物所用的時(shí)間為常量，因此，可以把它簡(jiǎn)單的加到運(yùn)行時(shí)間中去。</p>

64、<p>　　5．堆垛機(jī)只能以單指令要求和雙指令要求為基礎(chǔ)，例如，不允許堆垛機(jī)在巷道內(nèi)多次啟停。（這個(gè)分假設(shè)后來(lái)應(yīng)用于新設(shè)計(jì)的堆垛機(jī)完成四重作業(yè)流程。</p><p>　　6．為了符合最短鄰近的啟發(fā)思想， 取貨數(shù)n可用來(lái)排列，且在貨格內(nèi)有m個(gè)開放的位置。</p><p>　　5 雙貨叉堆垛機(jī)系統(tǒng)</p><p>　　新設(shè)計(jì)的堆垛機(jī)有兩個(gè)貨叉臺(tái),因此可以對(duì)

65、其進(jìn)行雙貨叉系統(tǒng)的操作:同時(shí)搬運(yùn)兩件貨物并分別把它們放置在指定的位置,在不同位置取兩件貨物并回到出入口,如圖4所示.上述工作流程能通過在四個(gè)不同的位置存、取操作來(lái)實(shí)現(xiàn)。因此，運(yùn)行時(shí)間將由一個(gè)單指令任務(wù)時(shí)間再加上三個(gè)運(yùn)行時(shí)間。為了更有效的完成上述四個(gè)操作，在完成一個(gè)雙指令任務(wù)操作中就包含完成了在一個(gè)位置存、取操作。這種被稱為四指令任務(wù)流程的模擬操作系統(tǒng)能減少運(yùn)行時(shí)間，因而比此前的所提的模擬系統(tǒng)要更能提高效率。四重指令任務(wù)流程能在倉(cāng)庫(kù)的任意

66、一位置完成存儲(chǔ)操作，而取貨程序是按照先到先服務(wù)的原則處理。即使如此，合理的按排取貨的順序也能顯著的減少四種操作中的運(yùn)行時(shí)間，Han 曾經(jīng)這樣分析以提高單貨臺(tái)立體倉(cāng)庫(kù)系統(tǒng)的工作效率。本文的分析也是以他們的研究為基礎(chǔ)的。</p><p><b>　　6 結(jié)論</b></p><p>　　本文對(duì)自動(dòng)化立體倉(cāng)庫(kù)中的一種雙貨架堆垛機(jī)進(jìn)行了較為詳細(xì)的分析，應(yīng)用這種倉(cāng)儲(chǔ)系統(tǒng)所帶來(lái)的

67、好處表現(xiàn)在以下兩個(gè)方面：</p><p>　　1．四種操作運(yùn)行中與單一貨叉的堆垛機(jī)相比，雙貨叉堆垛機(jī)可以提高工作效率的范圍是40%到45%。</p><p>　　2．一個(gè)雙任務(wù)操作中，雙貨叉的設(shè)計(jì)顯著縮短了運(yùn)行時(shí)間。</p><p>　　雙貨叉系統(tǒng)使提高倉(cāng)庫(kù)的工作效率成為可能。這種設(shè)計(jì)主要的缺點(diǎn)是要增加堆垛機(jī)的額外成本。在決定是否適合于某一特定情況時(shí)，對(duì)其經(jīng)濟(jì)估算通