AUTOMATED WAREHOUSINGGordon Skimmings, managing director ofSM Consultants Ltd of Windsor,gives an overview of developments in automated warehousing over the last

40 years, and examines present day systems.

Automated warehouses have beenaround for about 40 years. In the 1950sand 60s automation was restricted totaking the driver off the cranes which

stored and retrieved pallets from racking, coupledwith some elementary conveyors to transport thepallets to and from the cranes. Almost all installationsrelied on a card system to record pallet location.When the early small computers started to becomeavailable they were used to select the locations butstill relied on punched cards which were manuallyfiled and subsequently used for pallet retrieval. Inmany cases there was no direct connection betweenthe computer and the cranes. Cranes were eitheraddressed by keyboard entry or the insertion ofpunched cards into hard-wired control systems.Similarly, conveyors were controlled by hard-wiredrelay systems. The elementary nature of the availablecontrol systems and virtual absence of affordabledata processing at warehouse level imposed severeconstraints on the system designers. The complexi-ties of making changes to the hard-wired controlsystems had the effect of reducing designs to thebasic movement functions.

UK user companies were slow to accept theconcept of automated warehouses and for manyyears it was necessary to go to Germany, Switzerlandand to a lesser extent France and other EEC countriesto see installations. In some ways the late awakeningworked in the interest of UK designers. While ourcolleagues in Europe had many years start on the UK,they had become used to the concept of punchedcards. The awakening in the UK coincided with theavailability of the early generation of smallcomputers, which although not ideal, provided thebeginnings for integration of the machinery and dataprocessing. Thus UK designers, not hindered byconvention, were among the first to grasp the widerpotential and set the scene for the modern automatedwarehouse.

ObjtctlmBefore looking at the objectives it is useful to

define what we mean by an automated warehouse.Traditionally the term conjures an image of driverlesscranes working in narrow aisles, with pallet racking20 metres and above, high and a complex ofconveyors or AGVs. Most people will also imagine anew special purpose building to house theinstallation.

Dealing with the special purpose building beforegoing to the wider concepts, it is worth noting that

one of the most successful automated warehouses inEurope was installed in an existing building whichwas previously equipped with narrow aisle trucks.The warehouse holds 10 000 pallets and has athroughput capacity of over 100 pallets in and out perhour. 30% of the throughput is off-loaded from theincoming vehicles, stored, retrieved from the racksand loaded onto the delivery vehicles, automaticallywithout intervention by forktrucks at any stage.

In the wider concept, I would like to exchange theterm 'automated warehousing' for 'automation inwarehousing'. While many more companies couldand should take advantage of the improvements inthe quality of customer service and the longer termcost benefits which the automated warehouse has tooffer, many of the benefits are available toconventional warehousing if selective automation isapplied. And applied not only to the mechanicalequipment but, more importantly, to the collectionand processing of reliable key data, captured as ithappens with inbuilt recognition of human errors andinstantaneous correction by the operator. There is nodifference between the objectives of an automatedwarehouse and any other type of warehouse. Theyare:• To supply the goods to the customer or the user atthe time required and in the same condition as theywere received into the warehouse.• To provide up to the minute accurate informationon stock availability to the sales force and theproduction planners and buyers.• To provide a safe and challenging workenvironment which will attract and keep high qualitydedicated staff at all levels.• To achieve these objectives at a cost whichcontributes to the company's competitiveness in themarket place.

Wktrt are we now?

Conveyors, cranes, industrial trucks and evenAGVs and robots have been around for a long time.For many years they have been applied to what theAmericans first tagged as 'islands of automation'.That is, individual elements of the manufacturing andwarehousing operations which in themselves havebeen made efficient but still rely on unreliablematerial flows and poor out of date information anddirection. As a result, in many companies crisismanagement prevails.

The great technological development of thedecade has been the availability of affordable andreliable small computers and programmable equip-

ment controllers. The great current shortage is thepeople with the skills and imagination to apply thetechnology. While it is encouraging that theelectronics and information technology industry isattracting a growing number of very bright people,there is an underlying problem that most of them arejoining with no practical experience of the day-to-dayoperations which they are setting out to control. Thisplaces a heavy responsibility on the user, who tocompensate, must prepare a precise and completespecification of operational requirements. It isessential that if success within the timescale andbudgeted cost is to be achieved, that the specificationcovers in simple language, every eventuality whichcan occur in the day to day operation of the business.It must also take into account the skills andtrainability of the existing staff and the peopleavailable from the local labour market at the wagesthe company is able and chooses to pay. The goldenrule when writing a specification is, write it in simplenon-technical language and discuss it with thepeople who are actually doing daily the operation youare writing about. The British Materials HandlingBoard, in conjunction with the Department for Tradeand Industry have compiled an awareness packagewhich I recommend to anyone who is anticipatinginvestment in materials handling equipment orsystems. The package includes a comprehensiveguide to the specification of reqiurements.

Information technology interface

A badly equipped warehouse working with reliablestock and management data can be successful. Awell equipped warehouse working with unreliabledata will not be successful. The key to success iswhat we have come to call information technology.Information technology starts at and is only asreliable as the point of initial data capture. Except inspecialised circumstances where data can be readfrom and written to intelligent tags attached to theload or its carrier (a matter of cost), data capture isachieved by one of three basic methods:• Automatic bar code readers.• Hand held bar code readers.• Keyboard entry.

Bar code data capture requires a consistentacceptable quality label or printing on the unit load.The reader is connected to a computer which extractsrelevant data from the bar code. The advantage of abar code reading system is that, with one exception,you do not get wrong data entered and the same codecan be read throughout the distribution process to

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positively track unit loads. The exception, which mustbe guarded against, is that the wrong label may havebeen attached to the load. This can be guardedagainst by an operator (who is often present for otherreasons), checking man-readable characters on thelabel against what is written on the items which makeup the unit load. A more positive method involvesselective keyboard entry of what is printed on thepacks, with the computer comparing the keying andthe bar code reading.

Keyboard entry is still widely used and given acarefully thought out validation method, is success-ful. The way to minimise keying errors is to minimisethe number of characters to be keyed and to breakthem up into short strings. It is unreasonable toexpect a person to spend but a limited period on datakeying. Regular relief, or preferably sharing the taskwith other shift operators, is essential for consistentaccuracy and some mistakes are difficult to detecteven with validation. A common mistake made byoperators who are tired or have exceeded areasonable task period, is to key a common validcode which does not relate to the load which is infront of them. While this can be detected by requiringthe operator to key abstracts of the code, thus forcinghis attention back to what is in front of him, thefrequency of miss-keys should be monitored. In myview, one of the big spin-offs in informationtechnology is the facility it offers to monitor keyelements of the business and be warned what needsattention and when. While crisis management may bemore fun, customer service and cost control are morelikely to come from anticipation.

The availability of affordable small computerswhich can communicate with other small computers,data capture points, machine and equipment processcontrollers and main frame computers, has openedthe way to integrated up to the minute informationwhich can be made available on the desks and workbenches of those who need it. Companies no longerhave to take the great plunge, faith in hand, intocomputerisation. Computerisation can be, and isbetter done, in small digestible bites. But, to stay withthe same analogy, the whole meal must be planned.Intelligent people weighed down with routine workcannot be expected to recognise or respond to crisesbefore they occur. I believe that the competitivecompanies of the 1990s will have two things incommon: they will have invested in their businessbeyond the narrow minded 'two year payback1 policy(which is still operated by many companies), andthey will have looked at every component of theirbusiness and grouped the components into logicalsets for computerisation of the routine and signallingof early warnings of decisions that have to be taken.

While acceptance of computerisation is alreadywidely spread in distribution, links back through thewarehouse to the supplier are often tenuous. Toooften distribution planners have to rely on a definitionof stock availability which is the total stock in thewarehouse and not stock which is available aftersatisfaction of demands already in the pipeline. A

computer in the warehouse updated at the time ofreceipt of stock and the time of allocation of stock tomeet demands, with a terminal in the distributionplanning office, will provide an instant display ofavailable stock. It can also allow the planners toredesignate stock to meet more important demandsin the event of shortages. Do I hear 'obvious stuff,common sense' - yes, both of these, but there arestill many people, even in large companies, who aretrying to work without this basic information. If theplanner also has the facility to have displayed what isin production or on order and the date due fordelivery, his decisions on shortages for theoutstanding demands can be taken in the light of allthe facts. If he also has the facility to raise invoicesand loading notes after the load has actually beenwithdrawn from the warehouse, he has the flexibilityto respond to the facts. This is information technologyat work. The technology is in place and can beadopted in stages as the company can afford it and,more importantly, as the company has the resourcesto fully investigate and specify the requirements ofeach stage in the infinite detail which the suppliermust have to produce a robust system. There is agrowing number of software houses who areproducing warehouse packages but these are in theearly stages of development and in most cases arenot suitable without considerable bespoke softwareto meet individual needs.The good news is that theleading companies are engaged in substantialpackage development programmes aimed atminimising bespoke software.

The extent to which integrated informationsystems will be extended beyond the user companyto suppliers and carriers will depend on the volume ofbusiness between the parties. Current investmentcosts will preclude all but major customer-supplierlinks. The growing trend for major manufacturingcompanies to contract out their warehousing anddistribution to a third party distribution company hasresulted in the integration of the computer systems ofthe two companies to the point where they can beviewed as one system. A number of conventionalwarehouses of this type have been around for manyyears. More recently a major international third partydistribution group has established a company whichspecialises in automated warehousing. This com-pany will finance, design, build and operate adedicated warehouse with the information systemsfully integrated with those of the client company.Their first automated warehouse has been operatingsuccessfully for over two years. This approach offersadvantages to companies who, while wishing toachieve the benefits of automation and integratedinformation technology, prefer not to commit theircapital or do not have the resources and experiencerequired to achieve a successful automatedwarehouse. As in all things, having done it before isstill the best recipe for success.

Training

The complexity or otherwise of the training

required is a good indication of the quality of thoughtthat went into the design of the systems. The bottomline of automation in warehousing is the computerperipherals and the ease with which they can beused. Given well constructed menu groupings andscreen dialogues which guide the operator throughhis tasks, initial training is best restricted to jobtraining. By this I mean limiting the initial training topractice of the few functions which are necessary forthe operator to do his or her job. Many employees willbe content to stay at this level. Those who wish to gofurther can progress through additional job traininguntil they have achieved their potential.

Far from imposing restrictions on recruitmentfrom the available labour market or the employmentof existing personnel, properly designed automationand information technology systems can be operatedby almost anyone. If initial training is limited to theimmediate task the operator has to perform, the fearwhich many people have of technology which is newto them will be quickly dispersed.

Problems and risks

The problems do not lie in the technology. Withthe exception of high volume order picking there is acomprehensive range of reliable equipment availablefrom a number of quality suppliers. The risk liesalmost entirely in the specification of the operationalrequirements of the business and the configuration ofthe system to fulfil the requirements in a mannerwhich is robust against the inevitable changes in thenature of the business within the life of thewarehouse. The risks will only be avoided if thedesign team includes the skills to extract andinterpret the business requirements and theexperience in the application of technology to selectand configure the equipment into an integratedsystem. The selection of the design team is a skill initself. The basic team should be small in number,three or four people chosen from the basic disciplinesis ideal. These people should stay with the projectthrough to completion. They must have the time,especially at the outset, to produce a detailedspecification of the operational requirements. It isessential that this is done before the question ofequipment or suppliers is considered. The team willco-opt other disciplines and specialists when therequirement develops. These will include people fromwithin the company who will be asked to appraiseand criticise the specification of requirements beforecommitment to design. It is also essential that thespecification is written in operational and nottechnical language and is exposed throughmanagement down to shop floor level.

A common risk lies in unrealistic projectprogramming. It is normal for top management to delaythe approval to go ahead and then for the approval to beoverlaid with a desire to do it quickly. If the project teamhas the strength and purpose necessary to achievesuccessful completion, it will not allow these pressuresto curtail the preparation of the specification which is anessential ingredient of success. GS

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