Bench Talk

(Source: Old Man Stocker / stock.adobe.com; generated with AI)

In a Dubai airport, I hopped on board an uncrewed “people mover” to transfer from one terminal to another. The system hugs a set of tracks and follows a prescribed path repeatedly without depending on a human operator for navigation. These seamless Dubai operations are used in airport transit all over the world. While on it, I couldn’t help but be reminded of parallel use cases in robotics—automated guided vehicles (AGVs) and autonomous mobile robots (AMRs).

AGVs and AMRs transport materials and goods and have several implementations in warehouses, retail, restaurants, hospitality, and even medical settings. They play “fetch” in the transport of goods and thereby save on labor costs. An AGV is a robot that transports goods and navigates following a fixed path or track. Markers on the floor, such as magnetic strips or wires, act as guideposts for the robot to follow. An AMR is a more advanced version of an AGV. While it, too, is a transport robot, it uses various sensing methods and algorithms to find its way around a site. To determine which one you need, it helps to understand the differences between the two and the design considerations at play.

Key Differences Between AGVs and AMRs

As the names imply, the AGV is automated, whereas the AMR is autonomous. In that sense, the AMR is more intelligent and needs less human intervention for its operations, if at all. The biggest difference between the two robots is how they navigate a space. AGVs need a little more hand-holding than their autonomous equivalents. They follow predetermined paths or tracks laid out through magnetic tape, lasers, or optical tape, allowing the AGV’s cameras or sensors to follow the tape or line painted on the floor. The AMR, on the other hand, does not need such a constrained environment. It can move more autonomously without the need for guidance along the way. It can map and learn paths using LiDAR or computer vision technologies. Advanced algorithms like simultaneous localization and mapping (SLAM) enable an AMR to map and track its location so it knows where to move next. SLAM technology has been used by some friendly in-restaurant delivery robots that bring your order to your table.

Choosing the Right Robot for Your Operating Environment

The fundamental differences in how these robots navigate lead to additional differences between AGVs and AMRs, which are important considerations when considering investment in these technologies.

Operations Environment

If the environment in which the robot will operate is dynamic and changing, the AGV might not be your best bet. The AGV needs a much more prescribed route and works best in highly structured environments where traffic is predictable and tasks are routine. If a robot will always follow the same path to bring items to and from shelves in a warehouse, for example, and you expect the design to be in place for a few years, the AGV is a better choice. If the warehouse or other environments in which the robot operates are busier and unpredictable, robot navigation becomes more complex. Space for lanes where robots can move might be tight. In such cases, AMRs might be the better choice.

Costs and Flexibility

Because the AMR has more advanced sensors and algorithms, it is usually more expensive than the AGV. However, it is also more flexible and can be quickly reworked to satisfy changing requirements in the future. The AGV system is much harder to rip and replace, even if the overall costs might be slightly less expensive than the AMR.

Battery Life and Charging Stations

Both these mobile robots are usually battery-operated, which means they either need to be recharged or their batteries must be swapped out regularly for fresh ones. If the robot is operating in shifts, it might be convenient to assign workers the task of charging or swapping the battery every evening. But if many robots are being used or are very busy, it might be worth investing in automatic contact charging stations or even a battery-swapping robotic station. A large battery will last an entire shift and simplify the charging schedule, but it makes the robot heavier and uses more energy. Based on how heavily the robot is used, it might make sense to have a regular charging schedule or to interrupt work whenever the battery is low. Operators might also choose opportunistic scheduling, where the robot uses any downtime during daily operation to take a break and recharge.

Integration with Existing Systems

Whether AGVs or AMRs, the fleet of robots needs to integrate data with existing warehouse management systems (WMS) or other in-house software to ensure that the customer can use and extend their existing workflows rather than rip and replace them with a whole new process.

The use cases for AMRs and AGVs are likely to expand. Also, expect integration with advanced technologies like AI and the Industrial Internet of Things (IIoT) to shape how AGVs and AMRs are used. Both kinds of robots offer a slew of advantages. Making the right match will likely boost employee productivity and provide a valuable return on investment.

Conclusion

In an era of increasing industrial automation, facilities of all kinds are looking to streamline operations and reduce labor costs by automating transport, and both AGVs and AMRs offer solutions to this automation. Choosing between AGVs and AMRs depends on a facility’s layout, operational needs, and budget. While AGVs are ideal for structured, predictable environments, AMRs offer flexibility and adaptability for dynamic spaces. Carefully evaluating these factors will ensure a robotics solution that best suits your facility’s needs and environment.