Know your pick speed so you can calculate your Robotic Automation ROI
If you’re considering robotic automation, I encourage you to first calculate your current pick speed, then you can get your Robotic Automation ROI. This helps you understand the value of what increasing your pick speed by 2x, 3x, or even 5x means for your operation.
The largest cost within a warehouse is typically labor
A large portion of the operational cost comes from labor-intensive, inefficient manual order picking. Did you know that in a manual warehouse (one without automation), the average worker walks 12-15 miles per shift? All this time spent walking around the warehouse isn’t an efficient use of their time. All this required walking is the primary limiting factor to improving pick speed and therefore order fulfillment speed.
Pick Speed: Manual vs. Robotic Automation
We’ve found that the most straightforward way to show a warehouse operator the value of robotic automation is to show them. We give them a quick comparison of what their current pick speed is today, and then what their predicted pick speed and orders per day can be with the addition of robotics. Our goal is always to bring value to the customer’s business, and I mean their bottom line.
Once we know the current picking productivity of manual pickers in an operation, we can calculate the optimal number of pickers and robots needed. In fact, once we have this data, we can also estimate the Return on your Investment on your robotic automation implementation. The dramatic increase in pick speed combined with lower labor demand results in a dramatic reduction in operating costs starting day one. We find that many customers have paid for their robot implementation within a year.
Robotic Automation Implementation: Time to Payback
At Prime Robotics, we like to share what we know, and we’ve refined a warehouse operations optimization model that allows you to input key data about your operation so we can recommend a complete robotic solution. Our ROI Estimator Tool lets you see your predicted boost in productivity, the optimal number of robots, and estimated cost. It’s a great first step to show you the business value of robots. Check out our online Productivity and ROI Estimator Tool and try it yourself.
So, getting back to your current pick speed. How do you measure it?
Line Pick Speed. These are the lines on an invoice. If an invoice has a line for 10 cases of tomato soup, this counts as one pick even though 10 cases are picked.
Piece Pick Speed. In the example above, the piece pick speed is 10, even though they are all the same SKU. Piece picking is probably a more appropriate metric if you’re doing case picking. Picking 3 cases of something may take considerably longer than 1 case, so it’s better to use the quantity picked as the measure and not the number of lines.
Which pick speed metric should you use?
The pick speed you use to compare manual versus automated depends on the nature of your business. If you tend to have a small quantity of eaches that get picked, like 1 or 2 at a time, you want to use the Line Pick Speed as your determinant. This is because the relative time to pick one item or two items from the same slot is marginal.
You should take the total product picked for a shift and divide it into how many man-hours that work represents. For example, if ten people working for 8 hours would be 80 man-hours. If I picked 4,000 lines during that shift, then my pick speed would be 50 picks per hour.
Picking Speed in Manual Warehouses
In manual warehouses, you can calculate the picking speed of workers by calculating the number of order lines processed in a shift. Pick speeds typical for manual picking are in the neighborhood of about 25-50 picks per hour per worker. If the warehouse has an effective WMS that provides route planning for pickers, it possible to reach speeds at the upper end of this average. If there is not a WMS, or a just very basic one, pick speed is on the lower end of this scale.
A Pick Wall
Sometimes warehouses record faster picking speeds than these. If the items being picked are small, like screws, then a pick wall set up makes it easy for the pickers to quickly pick items. A pick wall is really efficient for high-velocity items that are small, but efficiency diminishes as the wall gets longer and requires a picker to walk farther between picks. Up to 80-100 picks per hour is possible, but not typical. A pick wall is not scalable to large numbers of SKUs.
Types of Robotic Automation in Warehouses
There are several types of robots typically deployed into warehouses. They fall into one of two categories, Goods-to-Person and Person-to-Goods.
Goods-to-Person robotic systems
In G2P robot systems, the picker stays in one place and the robotic system brings the goods to them so they may pick it. This robotic system might be an elaborate rack and shuttle system or mobile robots. In both cases, a worker spends their time picking items, not walking between places. G2P systems can achieve speeds of 250-500 picks per hour. Autonomous Mobile Robot (AMR) systems tend to get to the 250-350 picks per hour per person range.
Person-to-Goods robotic systems
In a P2G, pickers are stationed in zones around the warehouse floor and robots enter their zone when something in that area needs to be picked. The picker places it on the robot. Over time the pickers become familiar with the location of items and get faster. Persons-to-Goods robotic systems can achieve pick speeds in the range of 100-200 picks per hour. Although not robotic, traditional conveyor operations can bring a real speed boost. Typical pick speeds for warehouses with traditional conveyor automation range from 100-250 picks per hour. Therefore, a move from conveyors to a Persons-to-Goods robotic system doesn’t provide an advantage. This may reduce labor, but it has a high capital cost and high utility bills.
Prime Robotics’ Mobile Shelf solution
Prime Robotics’ MobileShelf is an AMR Goods-to-Person robotic system. It can maintain picking speed in the 300-350 range, depending upon the customer’s workflow and packing process.
Keep in mind, labor isn’t the complete picture of savings due to automation, but it’s the largest. For example, take a warehouse currently doing 4,000 picks per shift using 10 workers. If you automate your warehouse with a robotic system capable of 250 picks per hour, only 2 people are needed now. Whereas 10 were needed for manual picking.
Let us help you calculate your robotic automation ROI
When one considers the fully loaded cost of a picker, these savings add up fast. Our ROI tool helps you calculate your robotic automation ROI. Get in touch with us and we’ll walk you through it using your own operation’s data. We’re focused on helping customers design efficient warehouses that have a big positive effect on their bottom line. Learn more about our robotics solution for Warehouses.