What is a Storage and Retrieval robot?
A Storage and Retrieval robot, or SAR bot for short, is an automated system that handles the Storage and Retrieval of materials in a warehouse.
These robots move inventory around, picking and placing items to and from storage racks. SAR bots come in pretty much all shapes and sizes, from small robots that handle individual totes to massive cranes that move entire pallets.
- Flexible yet efficient: They can work 24 hours a day, 7 days a week without ever needing to stop. They optimize storage space by stacking inventory high up and close together. They also speed up the picking and putting away process by being far quicker than any human.
- Super accurate: SAR bots use barcode scanners and warehouse management software to precisely track and handle inventory; they know exactly where every item is stored and can retrieve it on-demand with high accuracy This reduces picking errors and ensures the right products get to the right customers.
How do these robots work?
Now you’ve got an idea of what SAR robots are, let’s break down how they operate:
- Navigation: The robots use guidance systems like lasers, vision systems, or magnetic tape to navigate the warehouse floor and track their position. They follow the most efficient path to the target location, avoiding obstacles along the way.
- Picking and placing: Once the robot arrives at the right storage bin, it can retrieve or store inventory using an automated arm. The arm is fitted with suction cups, grippers, or a platform to securely lift and move items. The robots are capable of handling a variety of shapes, sizes, and weights of inventory.
- Integrated software: Sophisticated warehouse management software integrates with the storage robots, maintaining an up-to-date map of the warehouse layout, inventory locations, and retrieval schedules.
The software optimizes the robots’ paths for maximum efficiency. It also tracks the location of every item so the robots know exactly where to go to fulfill orders or stock new inventory.
Why implement a SAR robot system?
There are quite a few reasons. Let’s break down the most important ones:
- They save a lot of money: Investing in automated Storage and Retrieval systems may seem expensive initially, but can significantly reduce long-term costs. SAR robots eliminate the need for human pickers and drivers, reducing labor expenses.
Over time, these savings can amount to millions per year for large warehouses.
- Much higher throughput: SAR robots can handle materials much faster than human workers. They don’t get tired or distracted and can work at maximum speed and efficiency around the clock.
This results in shorter delivery times and the ability to fulfill more orders. Some systems can pick up to 1,000 items per hour with near-perfect accuracy!
- Skyrocketing accuracy: Robots follow programmed instructions very precisely, so there’s little room for human error. They pick the correct items, quantities, and locations over 99% of the time.
This cuts down on costly mistakes, returns, and rework. Products also experience less damage since robots handle materials gently – and consistently.
- Maximized storage density: SAR systems make the most of vertical warehouse space with dense racking structures. Robots can store and retrieve inventory at heights of up to 100 feet, accessing every available inch of space.
This allows you to store more inventory in less floor space, optimizing your storage capacity.
How much do they cost?
The cost of an automated storage and retrieval system can vary a lot depending on the size and complexity of your operations.
Note: However, despite the initial capital outlay, AS/RS can provide substantial cost savings over the lifetime of the system through increased efficiency and reduced labor costs.
- The size, height, and layout of your warehouse will determine how much space you need for an AS/RS. If building a new facility, designing it specifically for an automated system can help maximize storage density and optimize operations.
Retrofitting an existing building may require expensive renovations to accommodate the system.
- What type of Storage and Retrieval do you need? The number of SKUs, size of inventory, and throughput requirements will determine whether a unit-load, mini-load, or shuttle-based system is right for you.
- Software and controls: Advanced warehouse management systems and logistics software integrate with AS/RS to automate and optimize storage, retrieval, and fulfillment processes. While yes, they’re expensive, they’re necessary for efficiently operating and monitoring the system.
- Professional installation and integration of the mechanical, electrical, and software components of an AS/RS can account for up to half the total cost. Ongoing maintenance and support are also critical considerations for the long-term success and efficiency of the system.
Types of SAR systems
Not all SAR systems are created equal. Let’s take a look at the most common ones:
- Aisle-changing cranes: These cranes can pick up entire racks or single bins and move them into and out of storage aisles. They're perfect when you have a high volume of diverse products with varying storage requirements.
The downside is they typically require more floor space and cost more than other options.
- Mini-load cranes: As the name suggests, these smaller cranes are designed to handle lighter loads, usually plastic bins or trays. They operate within a narrow aisle, so they don't need as much floor space as the aisle-changing cranes.
However, they may not be a good fit if you primarily store bulkier, heavier items. Mini-load cranes are a popular, cost-effective choice for many e-commerce fulfillment centers.
- Carousels: If you’re short on floor space, vertical carousels are a great solution. They use a rotating structure with shelves to provide high-density storage. Robotic extractors move up and down to retrieve bins or trays from the carousel.
While carousels maximize your footprint, they typically handle lighter loads and fewer total products compared to the crane systems.
They are expensive, though!
- Shuttles: Shuttles move on tracks along the floor of an aisle, grabbing racks or trays and delivering them to workstations. They don't require the same heavy-duty structures as the crane systems, so they may have a lower initial cost. However, they’re less versatile and can only access items along their feet. Shuttles work best in high-volume operations with consistent, repetitive tasks.
