What are the Differences Between AGVs, AS/RS, and AMRs?

When looking to automate a warehouse or distribution center, there are a few different solutions. Automated Guided Vehicles (AGVs) represent one of the first available options for automating internal logistics, but since then, other advanced technologies such as Automated Storage and Retrieval Systems (AS/RS) and Automated Mobile Robots (AMRs) have evolved. While these technologies are all generally designed to complete industrial tasks, they are all quite different.

In this guide, we’ll dive into the differences between AGVs, AS/RS, and AMRs.

What is an AGV? AS/RS? AMR?

AGVs: Automated guided vehicles are self-guided automated vehicles that travel independently through a warehouse or facility. These vehicles transport objects or materials without a human operator and are guided instead. How they navigate without human intervention is dependent on the associated environment, but AGVs generally use software, LiDAR, and cameras to move along predefined routes.

A subcategory of AGVs are known as "Fleet Chasers". Fleet Chasers are designed to follow and interact with a fleet of other vehicles. These vehicles are usually the primary movers that carry goods or perform tasks, and the fleet chaser's role is to assist, support, or manage the movements of this primary fleet.

The concept of a fleet chaser is often seen in scenarios where multiple automated vehicles, such as AGVs or AMRs, are working together within a warehouse or a manufacturing environment. 

AS/RS: Automated storage and retrieval systems are a type of warehouse technology that automatically places, stores, and retrieves product or inventory from storage locations on demand. AS/RS systems use advanced technology to automate this process. They replace large storage areas and can save floor space by increasing inventory storage density. 

AMRs: Automated mobile robots are vehicles that use advanced technology to navigate safely through their environment and intelligently understand their surroundings without a human directly overseeing operations. AMRs use complex artificial intelligence, machine learning, sensors, and path planning to comprehend the given domain. These vehicles move independently without requiring a fixed route. 

Our offerings at Cyngn specifically fall into this AMR category. Cyngn’s autonomous driving solution is integrated into existing workflows and helps build out the routes, loops, and missions that a driver would usually carry out. 

What are the differences between AGVs, AS/RS, and AMRs?

While each of these automated vehicle methods provides automation solutions to businesses, they differ in several key ways. 

Intelligence 

AGVs: Automated guided vehicles have little onboard intelligence and are restricted by the routes that are integrated into their given environment. They are typically guided by fixed wires, magnetic guide tape, laser navigation, vision guidance, etc. While an AGV can respond to obstacles by stopping, they are not able to intelligently navigate and re-route if there are disturbances. Automated guided vehicles essentially run on a predetermined track like a train. 

 Automated guided vehicles delivering goods in a warehouse.

Therefore, AGVs tend to involve tasks that require repetitive and efficient delivery of goods. Their main purpose is to transport materials or inventory from one place to another. These tasks require minimal instructions in comparison to automated mobile robots, which makes them predictable and reliable for repetitive tasks.

AS/RS: Automated storage and retrieval systems utilize intelligent software and robotics to efficiently store, place, and retrieve products. These systems are typically paired with Warehouse Execution Software or Warehouse Management Software. The microprocessor in these machines will process and carry out the commands from the warehouse software. 

In the past, other solutions such as forklifts would require an onboard operator. With automated storage and retrieval systems, operators can conduct these operations autonomously. 

AMR: Automated mobile robots can intelligently navigate their environment by using data collected from sophisticated built-in sensors and cameras, paired with intelligence software. Instead of requiring guidance like AGVs, an operator doesn’t have to oversee operations and the technology enables these vehicles to choose the most efficient path to the endpoint. 

Unlike an AGV or AS/RS that are limited in their response to unexpected obstacles, if an AMR faces an obstacle, such as a worker in the way, AMRs can use collision avoidance to avoid the object. The AMR will continue its path to its final destination by finding the best alternative route. The vehicle will either stop, slow down, or reroute its path to avoid collision with the person and minimize interruption to operations. 

Automated mobile robots sorting boxes. 

These intelligent automated mobile robot solutions are therefore attractive to many organizations. In fact, as of 2019, over 70% of order fulfillment operations and warehouses that have deployed AMRs noticed a double-digit improvement in cycle time, inventory efficiency, and productivity. 

Particularly, autonomous vehicle analytics can increase an operations’ productivity by up to 70%. For example, at Cyngn, our technology helps organizations aggregate information about vehicles to extract business insights. Intelligent analytic dashboards deliver information like status, measurements, and performance metrics to operators, helping businesses improve efficiencies in their workflow.  

Flexibility 

AGVs: Automated guided vehicles are limited to their fixed routes, making them less flexible than AMRs. Magnetic guide tape and wires tend to be installed directly into a given facility, meaning applications are more limited. 

While AGVs are a scalable solution in certain applications, for most, changes to their routes are more costly and disruptive. For instance, if a warehouse wanted to alter an AGV delivery task that used wire navigation, the organization would likely have to re-route the wires on the floor. This tends to be expensive and takes time, which in turn affects operational efficiency. 

AS/RS: Similarly to AGVs, AS/RS are not as mobile as AMRs. Automated storage and retrieval systems tend to move along a fixed rail, carousel, or track system to move or store objects. These routes are typically near aisles in the storage level system making their mobility limited by location. 

Their fixed storage structure also causes them to be difficult and costly to relocate or adapt to changes in business. However, an automated storage and retrieval system does provide flexibility if an organization wants to expand its inventory and therefore operations. An AS/RS can more easily connect to a new area of a warehouse, for instance, in order to combat growing inventory. 

Automated storage and retrieval system.

AMRs: Automated mobile robots are the most flexible option among these three vehicle types. AMRs use intelligent technology to create an understanding of their surroundings, meaning they can easily and quickly adapt to changes in their workflows. At Cyngn, our flexible, scalable technology allows businesses to transform vehicles into fully-integrated, self-driving fleets.  

Unlike AGVs or AS/RS systems, AMRs do not have to follow rigid magnetic guide tape or adhere to the fixed infrastructure of a storage structure. Instead, their goal is to dynamically find the most efficient path from Point A to Point B, while avoiding obstacles in the environment. 

In order to adapt to changing environments or operation needs, operators can efficiently make alterations to AMR missions. Operators can use AMR interfaces or fleet control software to control their tasks. This means that organizations can easily move forward when there are changes in their business, receiving more value and spending less money on changes.  

Automated mobile robots’ modular deployment system also makes them a scalable solution. For instance, a warehouse can begin with a few units and then add more vehicles to their operations when their facilities grow. Cyngn specifically enables organizations to shift the costs of vehicle upgrades and maintenance to smaller investments over time. 

Applications

AGVs: Automated guided vehicles are used in various applications to increase efficiency and productivity. In fact, it is predicted that the global AGV market will grow around 7.7% between 2021 and 2026 due to increasing demand for automation in the material handling industry. They are commonly used for transporting raw materials such as plastic, paper, rubber, and metal. Many organizations utilize AGVs to lower labor costs and shift workers’ attention to more valuable jobs. The three main types are generally tow vehicles, heavy load carriers, and automated forklifts.

Tow vehicles are estimated to hold the largest share of the AGV market in 2021. They have the highest capacity among AGVs for moving materials. Also called tugger automatic guided vehicles, they pull one or more, non-powered carts that receive loads manually or automatically. 

Consider a warehouse with multiple facilities in one industrial site. The organization can use tow automated guided vehicles to transport their inventory of heavy metal between their different facilities using wire navigation to create a more efficient transportation system. This type of AGV is productive in moving heavy loads or loads that require long distances with numerous trailers, in comparison to a single fork truck.

AS/RS: Automated storage and retrieval systems technology varies based on what system will be most efficient for the type of inventory present. AS/RS include carousels, mini-load and unit-load cranes, shuttles, etc. Each of these work to increase the efficiency of pickers and are productive in moving high volumes of loads in and out of storage, reducing labor costs and labor constraints caused by shortages. 

AS/RS are commonly used for picking, processing, and packing orders. Manually picking orders can account for more than 50% of the time linked to picking, making it a very time-consuming process. These systems increase picking accuracy while also making efficient use of floor space.  

For instance, if a business needed to continuously move small boxes that hold parts required for a machine, it would be very time inefficient to manually move each of these boxes. Instead, they would want to implement an automated, mini-load AS/RS system that moves smaller loads, up to 350 pounds. Mini-load stacker cranes would be able to retrieve and place the boxes on racks and the operator won’t have to move from their location. 

Automated storage and retrieval systems can also be used for staging orders for shipping that are outside shipping hours, transferring them into buffer storage. These systems can further buffer inventory and provide it on demand to operators at different stages in the operation process. 

According to ABI research, recent high volumes in the logistic sectors have led to an increasing need for AS/RS solutions. In particular, parcel shipping reached 95 billion in volume in 2020 and is expected to double in the coming years.

AMRs: Automated mobile robots can also be used in a variety of use cases to make processes in an organization more efficient and productive without disrupting workflows. Like AGVs and AS/RS, these vehicles can add value to a business by carrying out tasks that allow workers to shift their efforts into other, more productive tasks. They therefore allow businesses to optimize labor, which reduces labor costs, in addition to increasing safety.

There are generally three types of automated mobile robots, those that transport goods, aid in the picking process, and offer a sortation solution. More generally, AMRs are widely used for logistics, e-commerce, warehousing, in addition to data centers, healthcare, etc. 

We can specifically look at AMRs used in warehousing. Data shows us that the average size of a warehouse in the U.S. has increased by 143% in recent years. This opens up the demand for AMRs to assist in transporting goods and help with heavy lifting to allow workers to engage in more value-adding activities. LogisticsIQ’s report found that the global market for AMRs is projected to expand by 2025 to represent a market share of around 15% in the warehouse automation sector. 

Automated mobile robots facilitating sortation at a warehouse facility. 

Consider a warehouse that wants to automate its sorting process and implement automated mobile robots into its workflow. These automated vehicles will use intelligent technology to take a product, scan its label, and navigate the goods to the associated dispatch zone. AMRs will scan their surroundings and use this data to safely navigate to the area where the product must be placed in this sorting task. This type of AMRs will utilize a navigation system specifically designed for warehouse performance. 

This is just one example of how automated mobile robots can be used in the real world. At Cyngn, we can build these autonomous vehicles and operations to the specifications of a given business. This may include basic stop-and-go routes or much more advanced ones that include a random A to random B type of operation. 

Costs

AGVs and AS/RS: Unlike AMRs, AS/RS and AGVs have more infrastructure-related costs. Automated guided vehicles require costs associated with building out fixed routes for vehicles, such as wires that are embedded into a warehouse's floor. Furthermore, for automated storage and retrieval systems, organizations tend to have a high order volume that combats these initial, infrastructure costs. Factors that affect AS/RS systems prices include height, size and weight of the loads, the distribution system in place, etc.  

AMRs: While automated mobile vehicles are more advanced, they can be less expensive to deploy than the other two solutions. These vehicles don’t require the same wires, tracks, and other infrastructure required for ASRS and AGVs. In addition, AMRs are flexible and can easily adapt to changes in business, further making them a cost-effective solution. 

Alternatives

Several alternatives to Automated Guided Vehicles (AGVs) are emerging in the field of material handling and logistics automation. These alternatives often aim to provide more flexibility, adaptability, and efficiency in various industrial applications. In short, such mobile robots optimize material movement and material handling, and it's a matter of choosing the best robot for the job.

Some alternatives include:

1. Autonomous Mobile Robots (AMRs): These are similar to AGVs but are equipped with more advanced sensors and software that allow them to navigate and interact with their environment more autonomously. AMRs can adapt to changes in their surroundings and avoid obstacles without the need for extensive infrastructure modifications.

2. Drones and UAVs: Unmanned Aerial Vehicles (UAVs) can be used to transport goods across warehouses or outdoor spaces. They are particularly useful for areas that are difficult to reach using traditional AGVs or AMRs, such as large outdoor yards or tall storage facilities.

3. Shuttle Systems: Shuttle systems involve using small automated vehicles that move within racking systems to retrieve and transport goods. These systems are especially efficient in high-density storage environments like warehouses.

4. Conveyor Systems: Conveyor belts or roller systems can be used to move goods along a fixed path. These systems are particularly useful for continuous flow processes and can handle a high volume of goods.

5. Automated Storage and Retrieval Systems (AS/RS): AS/RS use robotic systems to store and retrieve items from racking systems automatically. They can handle a wide variety of items and are often used in high-bay warehouses.

6. Automated Crane Systems: These systems use robotic cranes to move and stack goods within a warehouse. They are particularly useful for handling heavy or bulky items.

7. Sortation Systems: Sortation systems use conveyors, chutes, and diverters to automatically sort and route items to different destinations. They are commonly used in distribution centers and e-commerce fulfillment centers.

8. Robotic Picking Systems: These systems use robotic arms equipped with advanced grippers and computer vision to pick and place items. They are useful for tasks that require dexterity and flexibility, such as order picking.

9. Tugger Systems: Tugger systems involve a central vehicle towing multiple carts or containers. These systems are flexible and can be easily adapted to transport different types of loads.

10. Automated Guided Carts (AGCs): Sometimes called "autonomous pallet robots", AGCs are smaller vehicles designed to transport materials within a facility. They are often used in applications where smaller loads need to be moved autonomously.

Is there a difference between autonomous and automated?

Yes, there is a distinction between "autonomous" and "automated" in the context of robotics, automation, and material handling:

1. Automated: Automation refers to the use of technology and control systems to perform tasks or processes without human intervention. In an automated system, the actions are predetermined and programmed in advance. It follows a set of instructions or a predefined sequence of actions. Automated systems are typically designed to repeat specific tasks accurately and efficiently. For example, an automated conveyor belt system that moves products along a fixed path without any human intervention.

2. Autonomous: Autonomy refers to the ability of a system or robot to perform tasks or make decisions without direct human control or intervention. Autonomous systems have the capability to perceive their environment, make decisions based on their programming or learning, and adapt to changes or unexpected situations. They often incorporate sensors, artificial intelligence, and algorithms to navigate, interact, and make decisions in real-time. For example, an autonomous mobile robot (AMR) that can navigate through a warehouse, avoid obstacles, and adjust its path to reach a destination, all without human intervention.

In the context of material handling and robotics, an automated system might follow preconfigured paths or rules to perform tasks, while an autonomous system has the ability to make decisions based on its understanding of the environment and real-time inputs. Autonomous systems are generally more adaptable and capable of handling dynamic and unpredictable situations, whereas automated systems are more suited for repetitive and well-defined tasks.