Frequently, customer orders consist of several positions or items which have to be merged for shipping. Techniques for order picking assist in putting together articles from different warehouse areas in an error-free and cost-effective manner. What are the advantages and disadvantages of the most important order picking techniques?
slips Based on a picking list which contains all information about the article and the storage location, the order picker takes the indicated quantity out of the storage location and ticks off the article in the list. Feedback to the warehouse management system is given once all positions of the list have been processed. The disadvantages of this system are in particular the processing time when order picking as well as the susceptibility to mistakes and errors through wrong storage locations, stock quantities or picking errors. That is why further, other procedures are applied or preferred to automate data acquisition and identification.
Here, the picking list is displayed on a device for mobile data acquisition, the terminal or hand-held device. This device, which is connected to the warehouse management system, allows entering quantities picked and shortfall quantities. Thanks to a hand-held scanner frequently integrated, the bar code of a pallet or a tote is scanned and the associated information are shown on the display. Applying this order picking method, you only have one hand free.
Here, the paper-based picking list is replaced by a headset with voice recognition function which is directly in contact with the warehouse management system. A computer voice communicates the picking instructions to the user who then may confirm the picking process by previously defined words or numbers. As hands are free and the user does not have to look at a display, this technology allows achieving a high picking performance. The voice recognition is ensured by voice profiles which each voice user generates himself / herself when setting up the system by simply saving the frequencies of his/her command words. This way, the order picker is able to enter the words also in his or her mother tongue. Using the pick-by-voice method, the warehouse staff has hands free and an unobstructed view during order picking. Via check digits, it is possible to quickly and reliably acknowledge the localization and identification of the right products at the picking location and to confirm order picking into the correct tote. The advantages of pick-by-voice are a high flexibility, simple scalability and low error rates.
Each time when starting a picking order, e.g. by means of scanning a bar code, the warehouse management system activates a display installed at the tote location or storage location. Thanks to the digital quantity display directly at the storage location the order picker is able to see immediately how many parts he or she has to pick from this location. Depending on the user, the displays may also light up in different colours. Hence, the likelihood of confusion is largely minimized. By pressing the acknowledgment button at the storage location display the quantity is registered in the warehouse management system. Hands are free during order picking and the user does not lose time when searching for order positions. New, flexible technologies with wireless, battery-controlled display modules are already in the process of being launched. As the pick-by-light displays are installed at the storage locations, the order picking process guided by pick-by-light is less flexible and thus more time-consuming and more costly in case adaptations become necessary. Given that it is extremely easy to familiarize new employees with this system, the employment of seasonal workers is significantly facilitated in case of strongly fluctuating order volumes.
With the most recent, state-of-the-art order picking method, the storing position and picking quantity of a product appear in the data goggles display. These goggles connect to the warehouse management system via WLAN and are able to determine the position of the order picker and his viewing direction by means of a position detection system, e.g. a camera with image recognition software. The data is displayed depending on the context, i.e. depending on the site, time, visual field looked at and status of order processing. By shortly touching the googles, an integrated scanner reads the bar code of the storage location as soon as this storage location is looked at and shows the number of products to be picked in the data goggles. If the employee is standing in front of the wrong storage location, a note is displayed in the googles display indicating the correct space. The next order is started by shortly touching the googles. Besides a high picking rate, the advantages of the pick-by-light order picking consist in reducing errors during picking by a visual representation of article images, checking the article numbers in the field of vision as well as by highlighting the storage compartment optically. A reduction of non-productive times and thus a performance increase is achieved by displaying different path and picking information simultaneously. In terms of quality and ergonomics of the data goggles, the next years are certainly expected to bring significant progress for order picking.