Pick and Put to Light Using Ignition

While many companies use Automated Storage and Retrieval Systems (ASRS) to manage inventory and the movement of material throughout their manufacturing operations, many processes still require manual pick and put operations.

Pick and Put operations involve either a pick list for getting materials from various locations in a warehouse, or a put list for putting materials into particular locations. These operations apply to manufacturing processes (where raw materials need to be brought to the production line and finished goods go to the warehouse for storage before shipping), and to shipping and receiving operations. For example, when you order from Amazon, the items need to be pulled from their warehouse shelves, put into boxes, then shipped to your doorstep. A pick to light and/or put to light system shines in these types of operations. Pick to light and put to light systems are also important components of Manufacturing Execution Systems (MES) which manage inventory across many production and business processes with manual operations performed by people.

How Do Pick to Light / Put to Light Systems Work?

For ease of reference, we will use the term Pick to Light for the rest of this article. A Pick to Light system is synonymous with a Put to Light system, except that the operation has the reverse outcome. In a pick system, you remove an item from a location and track its movement, in a put system you put an item into a location.

A simple metaphor would be to imagine going to your big box hardware store on the weekend to get some tools and materials you need for a project at home. You take your shopping list, look up where everything is in the store, and head out. As you push your cart down the aisles and pick items off the shelf, you cross them off the list. Once you have everything, you are ready to check out. This is the same process that a warehouse worker would use to pick orders, although they might be picking dozens of orders at a time and use a pallet full of boxes instead of a cart.

A Pick to Light system removes the guessing game of “where is each location?” from the equation. This is accomplished by installing hardware at each location. When an operator is ready to pick an order, they will scan it and each relevant location will light up. When they pick the items from that location, they can scan it as picked and the light will turn off. Once that order is complete, the locations will all be dark. If an operator is picking multiple orders, or if multiple operators are working, you can use lights in different colors for each operator/order to reduce confusion.

Implementing a Pick to Light System

To implement a Pick to Light system, you will need storage locations. They can be officially defined storage locations in an overall production hierarchy as defined by ISA-95, or they can be generic such as shelf locations in the warehouse. In our hardware store analogy, this would be similar to “Aisle 16 is where the bolts, nuts, screws, and other hardware are located, and the boxes of 1-1/4” Drywall screws are in Bay 12, so the location is A16, 12.”

Next, you need a database for tracking what items (and their quantities) are in each location. This is easy with a good inventory management system in place, but it may take some up front work to build if you don’t have a system in place already.

Then, you will need to generate pick lists for your operators—so that they will know which items they need to pick to complete a given order. This should be relatively easy if you are already using pick lists. The pick lists can also be generated by software and a tablet the operator carries around. In addition to items, quantities, and locations, you may also want to build in barcodes for each item and the order itself. The operator can then scan the current order to light up each location, and scan each part as it is picked.

Finally you will need hardware at each location to indicate to the operator that the location has items they need to pick for this order. For the systems we implement, we have really liked using the Wireless Displays from Voodoo Robotics. These displays are easy to install since there is no wiring. They also include a built-in light, button, and E-Ink display. They are configurable using an API, so changing the light color and updating the E-Ink display is easy to implement from a central system like Inductive Automation’s Ignition. You can also use a cart or dedicated storage bins to remove any guesswork for the operator. Put a wireless display on a bin, have it light up with the corresponding color for a given order, and the operator will see exactly where to find the items they are picking.

How Do We Use Ignition With Pick to Light Systems?

At Corso Systems, we use Ignition as the backend for all aspects of a Pick to Light System, and even some of the front end when needed.

Ignition can connect to any and all databases, so accessing the inventory in all locations is a simple task—assuming your data is well maintained. It also connects to ERP systems, so getting the information to generate pick lists is easy. We also build screens in Ignition for the operators to see all the details about any order.

Using the scripting engine, we can tie into barcode scanners—or even mobile device cameras using the Perspective Module. Plus, Corso Systems has a suite of tools built around the Voodoo Robotics platform to integrate seamlessly with their wireless displays.

Using Ignition as the backend for a Pick to Light System lets you integrate with your production scheduling system, ensuring that operators are picking the right orders at the right time to keep the plant operating at capacity. This capability was a key reason Blommer Chocolate went with Ignition for their Enterprise Integration. They installed barcode scanners and tablets on their forklifts which give the forklift drivers a list of upcoming orders, where the orders needed to be picked from, and which production line need the ingredients. If the schedule changes they get notified, and their pick lists update accordingly.

Wrapping Up

Pick to Light systems are a powerful addition to the manufacturing technology lineup. They help increase picking accuracy, decrease operator error, and streamline inventory management. You can easily add lot number priority so operators know to use the oldest stock first. You can also isolate lot numbers which are still waiting on quality approval for use.

Using the power of Ignition along with the tailor-made hardware from Voodoo Robotics, you can have a Pick to Light system set up and running without any wiring or modification to your storage locations. With all of the work done on the backend prior to commissioning, most Pick to Light systems can be up and running in just a couple of hours once you’re ready to deploy.

If you have any parts, materials, or ingredients which need to be transferred to or from a warehouse or storage location, you can benefit from using a Pick to Light System. To find out how we can help you, reach out and let’s chat!