Automated storage and retrieval systems (AS/RS, or ASRS) are computer- and robot-aided systems that can retrieve items and store them in flexible locations within a grid or shelving system.
As a very high density storage solution, ASRS is used when high volume loads must be moved rapidly and accurately. Let’s explore the main types of ASRS systems, how they work and their considerations.
Types of automated storage and retrieval systems and examples
Key types of ASRS include cubic ASRS, unit-load ASRS and mini-load ASRS systems. Unit-load ASRS is used for large loads such as handling full pallets or cases of items that weigh a few thousand pounds. A typical unit-load ASRS uses moveable-aisle cranes or fixed-aisle cranes:
Fixed-aisle cranes or Storage Retrieval Machines (SRMs) usually stay fixed to one area or row of pallets, in this scenario. They travel along the designated area or path to retrieve items.
Moveable-aisle cranes are similar, but they’re designed to retrieve or store items in multiple areas instead of along one path or aisle.
Mini-load ASRS, such as case-handling or tote-stacking systems, are smaller cranes or robots that handle lightweight loads such as trays or cartons. Mini-load ASRS typically use cranes or shuttles:
Mini-load ASRS cranes move along narrow aisles to retrieve or store products. It’s essentially a much smaller version of a fixed-aisle crane.
Mini-load ASRS shuttles run along a track and deliver items or move them between automated racking systems. Imagine a small flatbed truck that runs out and grabs a box, tote or tray for you. They can work at multiple levels if designed for the job, but most of them run along a single path.
Cubic ASRS is the most modern form of ASRS, consisting of a dense, modular grid full of bins containing stock. It’s based upon:
A sturdy, modular metal framework leveraging the vertical and horizontal space within a warehouse to its fullest potential, allowing for the storage of stock bins in an exceptionally dense, uniform manner
Instead of using SRMs or shuttles that move along rails between racks, cubic ASRS employs multiple computer-controlled robots that navigate the top layer of the grid, picking items or bins. Removing the need for aisles or rails within the grid significantly increases storage density.
Other types of ASRS include carousel-based systems and vertical lift modules. Carousel-based ASRS retrieve and store products with the help of an inserter extractor. The carousel spins until the shelf or bin is in the proper position for the inserter extractor to either place or remove the item. This system can usually move vertically or horizontally in a fixed area. Most carousel-based automated storage and retrieval systems handle smaller jobs than heavy lifters like unit-load systems.
Vertical lift modules (VLM) work in a similar fashion to carousel-based systems. In this case, the inserter extractor is located in the center of an enclosed structure and is surrounded by columns of trays on both sides. It locates the correct tray and delivers it to an operator who then completes the order and returns the tray.
How automated storage and retrieval systems work
Each type of AS/RS operates in slightly different ways, all with the goal of speeding up warehouse processes. Each type of system outlined above automates the process of storing products in appropriate bins, shelves or other storage locations or retrieving items or loads from storage areas. They reduce the time and manpower needed to retrieve and store items.
Advantages of automated storage and retrieval systems
Automated storage and retrieval systems offer many advantages, including:
Reduced labor costs
Improved accuracy, efficiency and productivity
Reduced safety risks for employees (reducing the need to lift and move heavy or bulky items)
ASRS can work in environments that aren’t ideal for human workers, such as freezer storage areas. They can function at heights that are difficult for human workers to navigate, as well, allowing warehouse operators to maximize floor space by making better use of vertical space.
How to choose the right automated storage and retrieval system
To keep pace with consumer demand, retain their competitive edge and maintain a robust bottom line, businesses need to utilize every square inch of warehouse space effectively, maximize asset utilization and improve labor efficiency. To this end, manybusinesses choose to deploy ASRS systems to automate warehousing and streamline product storage and retrieval operations.
However, the complexity of even the most basic ASRS systems makes choosing the right one a very challenging task. To simplify the selection process, let’s review some of the features and factors to look for.
Reliable software
ASRS systems have four major components:
Storage and retrieval (S/R) equipment
Input/output system
Storage rack
Computer management system
The computer management system handles the loading and unloading of SKUs in an ASRS system via a dedicated software that keeps track of inventory details such as:
The specific location of items
How long they were in storage
Where these items came from
The right ASRS should come with robust and well-designed Warehouse Execution System (WES) software to facilitate seamless orchestration of robots and scheduling of retrieval of stock bins. All instructions to the ASRS system are passed through this software, so you must ensure that it’s easy to use, reliable and free of technical glitches.
Height and weight limitations
While ASRS systems can be customized to handle virtually any type of item, certain types of systems are best for certain products. The system must be able to handle the maximum weight per unit load for your operations (approximately 5500 lb ). Shuttle and mini-load systems are designed to handle small loads (totes, cases, etc.) while unit load ASRS systems are ideal for heavier weights (large totes, drums, pallets, etc.)
Cubic ASRS is designed to handle the vast majority of consumer packaged goods, groceries, pharmaceuticals and other small to medium sized packages.
The vertical length should also match the overhead space of your facility. The most common types of storage racks are approximately 40 feet, although some systems can reach up to 100 feet. The higher you build your ASRS system, the less expensive (per vertical foot) it becomes. OSRS can be built up to 21 bins high, offering very high density of stock compared to traditional racking.
Speed
The right ASRS system should occupy a small footprint (to maximize floor space) and come with multiple speed options that can comfortably handle picking and order fulfillment operations during peak demand periods. For e-commerce operations, it’s best to deploy a system with a high-speed buffer designed for quickly moving high load volumes in and out of storage. Since inventory accuracy is extremely high, companies can lower the amounts of safety stock in storage and reduce work-in-process (WIP) inventory, allowing them to accommodate more SKUs in the same warehouse space and offer customers more product choices and faster fulfillment times.
Customer service
Always purchase an ASRS system from a vendor that offers fast and reliable customer service and/or an ongoing technical support package, with robust remote control or even physical support wherever possible. In the event of technical issues, a non-functioning ASRS system can create a domino effect of stoppages, reduced productivity and unfulfilled orders that can disrupt supply chains and result in an unsatisfied customer base. The ability to get professional help quickly is critical to your reputation and bottom line.
How much do automated storage and retrieval systems (AS/RS) cost?
As with most warehouse automation systems, the cost of an automated storage and retrieval systems can vary widely. The cost is dependent on several factors but can range from $70K for one standalone vertical carousel to more than $5 million for a fully integrated mini-load or cubic ASRS system managing tens of thousands of SKUs.
Some of the factors that influence the final cost of an ASRS system include:
The cost of the ASRS equipment itself
Overall size and weight of products to be handled
Storage space
Special handling requirements
Required throughput
The complexity of the software and machine controls
The cost of customizing and reconfiguring the equipment and your facility to maximize benefits
Cost of shipping, delivery and installation of the system
Integration with existing processes
Autonomous Mobile Robots (AMRs) Offer a Rapidly Deployed Alternative
For a lower-capex, quicker route to automation, Chuck AMR provides an alternative to AS/RS: autonomous mobile robots (AMRs).
Chuck AMR can be rapidly deployed within your existing infrastructure, performing putaway, picking, sorting and returning tasks. Chuck generally achieves ROI in under 18 months and can handle anywhere between 5,000 and 75,000 unit picks daily.
Chuck works alongside your human workforce to increase productivity and accuracy without requiring infrastructure changes. Chucks are intuitive to learn, so warehouses can get up and running with autonomous mobile robots in weeks compared to the months typically needed to implement ASRS systems. Autonomous mobile robots like Chuck AMR guide warehouse associates through tasks, augmenting your human labor, rather than replacing your human workforce.
Autonomous mobile robots are also easily scalable. In some cases, you can rent autonomous robots as needed to supplement your workforce during peak times. Once demand returns to normal, you can simply return the robots you rented until the next rush.
Let’s discuss the solution that’s right for you. Contact us today.
