Automate stores for faster service
June 1st 2004

Kevin Staines, sales director at Excel Automation looks at the benefits of automating stores and outlines factors that need to be considered when embarking on such a project Whatever we want to buy, whether it's for home use or business needs or inter-departmental requirements, what we all want to know (apart from price, that is!) the availability of the item and when it will be delivered. To answer these questions promptly requires a highly effective logistics operation, with carefully planned storage supported by an efficient logging system. An effective storage solution could be a simple racking system where locations are logged by pen and paper or a fully Automated Storage & Retrieval System (ASAR) solution involving computerised systems with automatic data capture. The logging process is key to the success of any storage facility, it effectively gives a vast array of knowledge, for example, product availability, stock holding and supply trends. It was not until automated storage that we had the opportunity and benefit of real-time knowledge. This was a fundamental necessity when the manufacturing industry turned to just-in-time supply requirements. Whilst many supply companies where able to support JIT with careful management of manufactured-component workflow, others introduced buffer stores. The buffer or intermediate store is ideally suited to sub-contractors unable to introduce fast changes to manufacturing processes due to the nature of the product produced the store allows them to maintain their JIT deliveries without shortfall. Having seen the benefits of JIT, its concepts and applications were harnessed and refined by the commercial organisations supplying to the public via distribution centres. Automatically generated pick lists, manual or automated item collection, auto-routing by conveyors to pack lines and then onto despatch are all elements of a storage system that paved the way for TV Shopping channels and on-line buying, as well as allowing some high-street retailers to cut shop-storage, thus giving more space to the sales floor. Store benefits Implementation of a logistics operation that features advance data communications linked to an ASAR system fed by conveyors has a far reaching effect, benefiting operational efficiency and cost. The main areas of concern or interest are: 1 Employees' absenteeism does not affect functionality of the storage operation. 2. The use of high-rise racking reduces floor area, allowing more dense storage in a smaller footprint, a major bonus when considering spiralling real-estate prices. 3. As we stack higher we must consider manual handling limits. Lift trucks and cranes allow heavy loads to be carried and stored more quickly. 4. Data communications provide immediate up-dating of product availability, can give alerts on low item levels, etc. 5. ASAR systems respond more quickly to down-line and up-line requirements. When developing any type of store it is important that there is a clear brief in terms of what is expected. If this is to be an automated store the provider should become fully conversant with their client's goals, understand their products and the flow-path often a store cannot be looked upon in isolation of the overall process. Things to consider include: What type of store is it a dedicated goods-in, an intermediate store, a finished goods store or a mixture? What type of products round, square, fragile, etc.? What is the maximum and minimum physical unit size? What will items weigh minimum and maximum? How will they be stored on pallets, boxes or loose? How will they be stored as complete boxes or broken into smaller units? How will products arrive at the store interface AGV, shuttle car, conveyor, lift truck? How will they be tracked will an operator manually scan a barcode on entering and leaving the store or will auto scanning take place? How will products leave the store cranes transfer items to collection station for scanning prior to release via conveyor, fork truck, etc.? Are there safety issues man-machine interface, hazardous loads, etc.? How much floor area has been allocated for storage, what are the maximum dimensions? Is there any height restriction due to building structure? What is the constraint on floor loading? Will there be planning issues? Whether a consultant or an industry-sector person, it is important to glean as much information as possible, about the product, what is expected of type of storage and retrieval operation and site details. Stores in action We look at the most progressive and fastest growing specialist book wholesaler, Gardners Books, examining the operation of a Bulk Store and an Automated Crane Store. In developing both these new sections, accumulation conveyors for the goods arrival department were supplied and for the bulk store a completely automated storage and retrieval system has been installed comprising four, fully automated stacker cranes, associated pallet conveyors and a shuttle car. Handling over 250,000 titles, more than 5 million books plus a comprehensive range of audio tapes and multi-media CD-ROMs requires a highly focused business structure, with sophisticated order processing systems supported by automated handling systems. New stock arrives by road at the arrivals hall, where order verification takes place before unit loads are broken down and re-allocated destination routes. They are sent either directly to the pick-face within the order picking warehouse for immediate stock replenishment or into the bulk store. Items held in the bulk store are fast-moving titles, this reserve stock ensures that Gardners is always able to maintain next-day despatch. The automated cranes each have an operating height of 15m and a double reach capacity to either side of the main mast, this maximises storage density from a single aisle. Each is a self-contained unit equipped with an on-board controller and software that interfaces directly with Gardners existing network. Palletised items arriving at the bulk store are automatically fed, via a comprehensive pallet conveyor system incorporating both profile and weight check, onto the shuttle car and then carried to the appropriate crane pick-up point. A storage location is assigned to each unit-load as it is transferred to the shuttle car. This controls the stop position of the shuttle. The shuttle incorporates a roller conveyor bed that simplifies loading and a chain transfer that allows the load to be driven from the shuttle onto a chain conveyor situated at crane pick-up positions. The load finally comes to rest on a scissor lift that enables the load to be automatically raised to the correct height ready for pick-up by the cranes telescopic forks. Once transfer is complete the crane automatically takes the load to its allotted rack position to await call-out for stock replenishment. Retrieval from the bulk store is a reversal of this operation. The last decade has seen major changes within book wholesalers, with Gardners spearheading changes in supply-chain management, providing todays booksellers with an unparalleled service comprehensive stockholding, high fulfilment rate, next day delivery and an e-commerce facility through its Gardlink electronic ordering system. Individual products rarely create the best solution, it is the understanding and joining together of mechanical devices that so often provides the best solutions. In our case study example conveyors, scissor tables and automated stacker cranes have been linked to create the required automated store. Tracking developments Handling devices provide only the mechanics for the physical movement of goods, it is mainly the optoelectronics industry that adds the interface to provide information for controlled movement and allows us to gain knowledge of our automated store. In any application a host of devices could be deployed barcode readers, omni-directional scanners, RFID devices, optical data transmission and distance measuring systems, profile measurement, colour and recognition sensors. There is also a wide range of machine guarding systems that bring safety to the whole automation process. It is within this area that we are witnessing changes that bring about increased benefits to our automated store, allowing us to extract more data, more accurately and more efficiently. Vision systems are rapidly entering the handling and storage industry. These camera-based systems enable multiple amounts of different data to be collected in one shot as a package and code label passes. It is a major asset in the quest for full traceability. An important change in the handling industry that brought about better working environment for staff in distribution centres happened around four years ago when a new conveyor and drive emerged the Excelvayor 500UB. It offered speeds in excess of 60m/min, noise levels below 65dBa, the belt drive was totally enclosed all features that still lead the roller conveyor market today and since its introduction it has proved extremely reliable. The design also features accumulation as standard and clear side panels for visual inspection. Warehousing operations and manufacturing plants are both reaping the benefits of improved safety, faster operational speeds, and quieter operation with less but easier maintenance.

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