Automated Lift Trucks On the Double

To stay competitive, distribution centers (DCs) need to reduce costs while addressing numerous other challenges, such as increased numbers of smaller orders, reduced order lead times and ever-higher reliability requirements. Some companies have considered installing automated systems but have been discouraged by the high cost of changing the system to adapt to future requirements.

One emerging alternative involves retrofitting standard warehouse lift trucks with automation kits. Such a solution, if properly implemented, has the potential to deliver higher productivity while maintaining the flexibility of the manual method.

Retrofitted lift trucks automatically fetch empty pallets, follow the operators to each picking location, position the forks at the right height and deliver the goods to dispatch, leaving the operator free to start immediately on the next picking assignment. This approach typically provides 60% to 100% higher productivity than the traditional manual approach. The cost is considerably lower than alternative automation approaches because it makes use of relatively inexpensive and often already existing lift trucks. It can be adapted to new products or facility layouts, and the automated lift trucks can even be moved to different facilities.

DC Challenges

DCs face unprecedented challenges in today's difficult economic conditions. The slow economy, just-in-time manufacturing and the changing face of the retail industry have all combined to force DCs to deal with a larger number of smaller orders. At the same time, customers are demanding shorter lead times and higher levels of reliability. DCs are also faced with adapting to rapid changes in product mix and volumes.

These trends tend to increase unit labor costs at the same time that DCs are facing unprecedented pressure to reduce costs. Labor typically accounts for more than 50% of a DC's total operating costs, and a study shows that order picking accounts for more than 40% of labor costs or about 21% of total operating costs. Clearly, addressing today's challenges requires finding ways to better manage the order picking function and better utilization of the workforce.

Some DCs have addressed this challenge by attempting to automate order picking. Conventional automated systems, however, are designed for handling very high volumes of a relatively small number of products with similar sizes and shapes. It may be difficult, then, to justify fixed automated systems for low-volume operations. Also, traditional automated systems can sometimes be difficult to modify to adapt to changes in volume or product mix.

Automated Concepts

The automated lift truck concept presents an alternative approach to automation that fits a wide range of DCs. The basic idea of the automated lift truck method is to make the most of existing resources, including pickers and lift trucks, rather than starting over from scratch. This approach is based on a system solution that integrates with most warehouse management systems (WMSs) and picking technologies, such as pick-by-voice or handheld scanners.

The WMS sends the customer order to the picker and the truck simultaneously. For example, the picker will get information via headset that the first pick for a new order is in location 24 in aisle five. The picker will walk to that location, which will normally be very close to his current location because of optimization provided by the WMS. Simultaneously, the automated system will dispatch the lift truck to arrive at the same time as the operator. The lift truck arrives with the forks positioned at the proper height for efficient and ergonomic order picking. The picker picks the item, and the next order line item is then sent to the operator's headset. The truck automatically travels to the next position along with the picker. When the pallet is almost full, the system sends a new truck with an empty pallet to the picker. The truck with the full pallet automatically travels to the dispatch area.