Design innovation maximizes efficiency and lowers costsBy Peter A. Buxbaum, AJOTFor years, logistics thought leaders have advocated changes in how products are distributed. Logistics, they argued, should not be thought of simply as a cost center, but should be reconfigured to provide companies with a competitive advantage. The same philosophy has led to a rethinking of the role of warehouses and their metamorphoses into distribution centers. The name change is not merely semantic. Warehouses were designed to maximize storage space and minimize cost. Distribution centers were configured to provide for maximum distribution efficiency. But distribution center design did not catch up with its reconstituted role in the supply chain. A cost mentality contributed to design rules that maximized storage density and space utilization. Researchers have found, however, that designing a storage area to maximize storage leads to higher operational costs of retrieving items from the space. Their new approach to distribution center design recognizes their emerging role in providing a competitive advantage to industry. This is especially true when it comes to the Internet economy. Customers order products online, and they expect to receive their items as soon as possible. In this new environment, distribution centers have become more than a place to store extra product. They have become an essential part of the supply and distribution chain. Researchers from the University of Arkansas and Auburn University say they have found a way to make distribution centers more efficient by helping companies retrieve products from warehouse shelves faster. This discovery, they contend, will make the distribution process more efficient, which means that customers will receive their items quicker. “Our results suggest that radically new designs could lead to faster retrieval rates and significantly reduced costs for operating distribution centers,” said Russell Meller, professor of industrial engineering and director of the Center for Engineering Logistics and Distribution at the University of Arkansas. Meller and Kevin Gue, an engineering professor at Auburn University, studied configurations of racks within warehouses and found that despite the increasing demand for more efficient and rapid distribution of products, conventional designs of distribution centers have not changed. Even worse, the conventional designs constrain productivity, Meller said. Specifically, he and Gue discovered that two unspoken design assumptions, neither of which is necessary from a construction point of view, limit efficiency and productivity because they require workers to travel longer distances and less-direct routes to retrieve products from racks and deliver them to designated pickup-and-deposit points. “For many years, companies treated warehouses almost exclusively as cost centers,” Meller said. “This led to restrictive design rules that focused on storage density to maximize utilization of space. Unfortunately, designing a storage area exclusively to maximize storage density ignores the operational cost of retrieving items from the space.” Lowering storage density while improving order-picking response times The restrictive, conventional design is a system of parallel picking aisles that, depending on the size of the distribution center, are sometimes separated by one or more cross aisles. Within this configuration, the unquestioned design assumptions are that cross aisles are straight and must meet picking aisles only at right angles, and that picking aisles are straight and are oriented in the same direction. Meller and Gue challenged these assumptions and developed two alternative designs that accept lower overall density of storage space but improve order-picking response times. A traditional warehouse with twenty-one picking aisles has no cross aisles. The researchers’ “Optimal Cross Aisle” model, on the other hand, inserts two diagonal cross aisles that originate at the same pickup and deposit poi