Historically, we talked about warehouses as being manual or highly automated. Manual warehouses are more flexible, they adapt much more easily to change. Highly automated warehouses have much higher throughput, but their cost and lack of flexibility can make them a risky investment. But really, there are automation solutions that are highly flexible as well. Autonomous mobile robots have been getting a lot of press. But I’m also starting to hear more about AutoStore. At the HighJump Elevate conference, I heard about Parts Town’s implementation of this flexible automation technology.
Flexible Automation
Flexible automation can better handle changes in order volume, but they also have much higher throughput than manual warehouses. AutoStore is one example. AutoStore is essentially an automatic storage and retrieval system (AS/RS) with more intelligence and scalability. Whereas a traditional AS/RS has a set footprint and can’t scale, AutoStore can. And in an AS/RS, if the stacker crane breaks, every picking location in that bay is affected. With AutoStore, there are multiple points of failure. If one robot breaks, the robot can be quickly rolled off the grid, and then the other robots go back to work.
The AutoStore Solution
An AutoStore system is comprised of a structural grid, storage bins, robots, and ports (pick and put-away stations). Products are stored in stacked bins within grid. As a stock keeping unit (SKU) is needed to fulfill an order, the control system alerts a robot to find the bin containing the item.
If the bin is buried beneath other bins, a robot places the extra bins on top of the grid until it retrieves the desired bin. It then takes that bin to the edge of the grid and delivers it to the operator fulfilling the order. As the bin is delivered, another robot on top of the grid returns the other bins to their original storage location.
As this process continues, the control system measures how often SKUs are needed. The bins with faster moving products begin migrating up toward the top of the system, where they can be retrieved more quickly. Bins with slower moving SKUs end up migrating to the bottom of the stack.
AutoStore is scalable. The structural grid can be expanded out while continuing to operate; this creates the ability to create more storage locations. As the storage locations grow in number, more pack stations and robots can also be added.
AutoStore at Parts Town
Kenny William, the Director of Process Improvement at Parts Town and an entertaining speaker, told an engrossed audience about their implementation of the AutoStore solution.
Parts Town is the largest and fastest growing supplier of foodservice equipment parts in the world. The company offers same day shipping of genuine OEM parts. Parts Town’s warehouse is located near the UPS hub, which facilitates faster shipping.
The company has had 14 consecutive years of organic growth of over twenty percent. This has led them to move to larger warehouse on three different occasions since 2004. The last move took them from a 150,000 square foot warehouse to one twice as big.
The solution went live last November 2017; the hardware was ordered in September of 2016 and arrived in February. It took five weeks to erect and seven weeks to put in the bins. Meanwhile the software implementation was going on in tandem and took about five to six months.
The hardware came from AutoStore, the system integrator for AutoStore was Bastian Solutions. Bastian Solutions also provided the the warehouse control system (WCS). The solution was integrated with HighJump’s warehouse management system (WMS) by 4Sight.
There are currently 29 robots and 15,100 storage bins on site. Bins are stacked 16 levels in height. The bins can be subdivided to accommodate multiple SKUs per bin. Parts Town subdivides bins into eighths, quarters, halves and the remaining 70 percent are undivided. There are also six ports, two for put-away and four for picking.
The solution offers a variety of advantages:
- It offers four times the picking throughput.
- Picking accuracy improved over 50 percent.
- The increased throughput has been accomplished with no injuries; goods to person offers improved ergonomics as pickers are not on ladders stretching for a pick or having to bend down low to select a product.
- The system is easy to learn. It can be learned in hours as opposed to weeks.
- The system overs incredible storage density. 55 percent of the picking is being done in the 2 percent of space occupied by AutoStore.
- Storage density means that this fast-growing company will not have to move into a new warehouse as quickly as they might otherwise have to. Continuing to serve customers while moving warehouses is not easy!
It is, however, not inexpensive. It was a multimillion-dollar investment whose payback period is roughly four years.
Here are some tips and lessons learned:
- The lead time to get an item picked is half an hour. That is how long it takes to pick items that are stored at the lowest level of AutoStore.
- Not all goods can be stored in the system. Some items are too large. PartsTown also elects not to store any goods in the system which can spill (liquids or powders), nothing that is hazardous, nothing that is greasy to handle, and no item that requires special tools to process.
- Not all items should be stored in the system. It is more economical to have the very fastest moving goods and the slowest moving goods picked manually.
- Orders that contain SKUs from both AutoStore and the manual portion of the warehouse must go through an additional consolidation station, which negatively impacts productivity. Consequently, Parts Town continues to expand the number of items held in the system.
- Proper slotting improves the throughput. A movers should be stored in a bin with other A movers, B movers with B movers, and so on.
- Put your fastest pickers at the pick ports and your most accurate workers at the put-away ports.
- Drop orders to the system as you receive them. Trying to sequence orders for the system will only act as a constraint that will slow the process down.
- Integrating the solution to a flexible WMS can lower risks. Their HighJump WMS is a more flexible solution than the warehouse control system. Consequently, picking and printing at the pack station is controlled by the WMS.
- The solution really does scale. Since the initial installation they added eight robots and an additional picking port.
- Adding robots adds speed. Since adding the new robots the throughput increased 15 to 20 percent. However, adding robots is subject to diminishing returns.
- Change management is critical! Because Parts Town is growing so rapidly, they were able to reassure workers that no one would be laid off as a result of the automation.
In conclusion, Mr. William said, “we treat AutoStore like it prints money, because it does!”