User:Bschoenb/"pick-to-light"

Pick-to-Light is one of the "paperless" picking methods. Instead of a picking or picking list, the items and quantities to be picked are sent to the picker via a compartment display arranged directly on the removal compartment.

Synonyms for Pick-to-Light include Pick to Light, pick-by-light or pick-2-light (P2L). The term Put-to-Light describes the reverse procedure.

Pick to light is a mature technology with wired solutions first implemented in the 1980s and wireless picking solutions beginning to emerge approximately 2016.

Because traditional wired pick to light does not offer the flexibility that many clients need, and the costs of installing and maintaining wired solutions are high, some companies are reluctant to use pick to light or have begun to seek alternatives.

How it Works
A pick-to-light display consists of at least one eye-catching light that pickers can see from afar and an acknowledgment button, which the picker uses to confirm the removal and reports the inventory change back to the warehouse management system in real time. Most displays also have a numeric or alphanumeric display to show the order picker the removal quantity and any additional information. To correct the withdrawal quantity (e.g. in the case of shortages) or for inventory functions, the device may have correction buttons (+/-), or additional function keys to call up special functions.

As an alternative to acknowledgment by button, the picker may use a barcode scanner or a sensor can monitor the intervention. Depending on the area of ​​application, a pick-to-light system may light in series (e.g., after acknowledgment the next device lights up) or in parallel (all light up at the same time for an order or kitting use case).

Put to Light
The term put-to-light refers to the reverse process to pick-to-light. In this case, the picker deposits the items rather than picking them. The same compartment displays are used as with a pick-by-light system. Put-to-light systems are used in two-stage picking. To do this, several orders are first combined in a so-called "batch" (lot) and picked at the same time in order to save travel and picking times. The items are then allocated to the individual customer orders using the put-to-light system. One or more shelves equipped with compartment displays are installed at a distribution or sorting station. The picker now scans the items from the batch container one after the other. The compartment display of the associated distribution compartment then lights up.

Combined Methods
Both methods described above can also be combined for an additional increase in efficiency. For this purpose, a compartment display is installed on the back of the Put-to-Light distribution racks. This shows the packing employee which of the distribution compartments already contain all the articles belonging to the order, i.e. have been picked. To do this, the eye-catching light (e.g. in green) is switched on. The packer removes the items and confirms this with the acknowledgment button. The eye-catching lamp goes out and the compartment is free for the next customer order.

Mobile Picking Systems
Pick-by-light systems achieve their maximum efficiency with short walking distances and high picking frequency per storage location. In the opposite case, for example a spare parts warehouse with long routes and low picking frequency per storage location, mobile picking systems offer a suitable solution. For this purpose, standardized or customer-specific vehicles are equipped with a power supply, WLAN connection, operator guidance and specialist displays.

The control software bundles a number of picking orders according to the number of compartments available on the picking vehicle. The order picker then "marries" the individual orders with the compartments on the vehicle. Via the operator guidance (visually via a display), the order picker is guided with the vehicle in a route-optimized manner from one picking point to the next. The compartment displays on the vehicle show the correct storage compartment and the storage quantity. The deposit is reported back to the host system via the acknowledgment button, and the next removal point is displayed via the operator prompt. In this way, a picker can pick several customer orders at the same time in a route-optimized journey.

Integration of a Pick-to-Light System
In order to be able to use all the advantages of a pick-by-light system, the connection to the higher-level system (usually a warehouse management system (warehouse management system) or ERP program) is of essential importance. The order data must be transmitted quickly and securely, as must the acknowledgment, correction or special function messages. The workflows and processes must be well defined in advance and mostly customized.

Benefits

 * Reduced search time
 * Direct feedback to the warehouse management system:
 * Acknowledgment of withdrawal
 * Correction in case of missing stock
 * Fewer picking errors due to incorrectly picked items or overlooked items
 * Due to fewer mistakes, higher customer satisfaction and fewer returns
 * Extremely short training period, resulting in high personnel flexibility
 * Greatly reduced order processing times
 * Modern systems recognize failures such as timeouts or pick-to-light equipment failure independently, recognizing that the picker has not picked or acknowledged all items in an order
 * Using multiple light or pick-to-light device colors enables pickers to work on many orders simultaneously within a zone.

Cons

 * Some pick-to-light solutions only allow one order at a time per zone
 * If the pick-to-light device does not enable pickers to adjust the quantity, the picker or a supervisor must adjust the quantity available through the warehouse management system
 * An undetected failure of a display may lead to errors in picking.

Alternatives to Pick to Light

 * [|Vision picking technology]
 * Voice picking technology