AMR vs. AGVs: Why Knowing the Difference Is Important in Today’s Manufacturing Facilities and Warehouses

Ed Mullen, Contributor

At Metro Plastics, an Indianapolis-based producer of custom plastic injection molded parts and inject mold tooling, finding new and innovative ways to automate material transport has been instrumental in its success as it competes in today’s increasing challenging manufacturing and job environment. With as many as 20 jobs running at a time, boxes of finished products used to stack up at each press until a quality inspector could make her way around the floor to inspect parts and have them delivered to the warehouse. During busy periods, boxes and pallets were tripping hazards for workers, and the constant forklift traffic added to the safety risks.

The company had long been investigating deploying automated guided vehicles (AGVs), which are guided by wires, magnetic strips or sensors typically built into the floor of a facility. When Metro built a brand-new facility a few years ago, however, cost and the disruption the installation would have caused made them look elsewhere. According to Ken Hahn, President of Metro Plastics, that’s when a distributor introduced them to an autonomous mobile robot (AMR).

“It didn’t need any wires in the concrete,” Hahn said. “It didn’t need magnet pills or anything else to guide it. It was autonomous, and it was basically about half the cost of the other solutions. It was a no-brainer for us to get it.”

Why AMRs Over AGVs?

According to a recent study by ABI Research (https://go.abiresearch.com/lp-36-transformative-technology-stats-to-know-for-2021), by 2025, AMRs are poised to exceed AGVs in global annual revenue, with AMRs growing to $35.266 million and AGVs at $30.452 million. For Metro Plastics, cost and the promised disruption to its infrastructure were key factors in its decision to deploy AMRs to initially transport finished goods to quality assurance. But that’s not always the case. Let’s look closely at the differences that are pushing many manufacturers toward AMRs for material transport.

  • Fixed Routes Vs. Intelligent Navigation
    An AGV has minimal on-board intelligence and can only obey simple programming instructions. As Metro Plastics has found, the AGV is restricted to following fixed routes, requiring high costs and lengthy disruptions to install and then additional cost and disruption if changes are needed. The AGV can detect obstacles in front of it, but cannot navigate around them, so it simply stops in its tracks until the obstacle is removed.

In contrast, an AMR navigates via maps that its software constructs on-site or via pre-loaded facility drawings. An AMR uses data from cameras and built-in sensors and laser scanners, as well as sophisticated software that enables it to detect its surroundings and choose the most efficient route to the target. It works completely autonomously, and if forklifts, pallets, people or other obstacles occur in front of it, the AMR will safely maneuver around them, using the best alternative route.

  • Few Applications Vs. High Flexibility

This autonomous operation also makes an AMR far more flexible than an AGV, whose fixed route means it basically performs the same delivery task throughout its service life. Changes are simply too expensive and disruptive to be cost-effective. An AMR only needs simple software adjustments to change its mission, so the same robot can perform a variety of different tasks at different locations, automatically adjusting to meet changing environments and production requirements. AMR tasks can be controlled via the robot’s interface or configurated by fleet control software for multiple robots that automatically prioritizes orders and the robot best-suited for a given task based on position and availability. Once a mission is established, employees do not need to coordinate the robots’ work, which allows them to focus on high-value tasks that contribute to the manufacturer’s success. In addition, an AMR’s open platform enables different top modules to be added on top to create multiple applications that meet each manufacturer’s unique material handling needs.

  • Suited for Traditional Business Models Vs. Made for Agile Businesses

Unlike AGVs, AMRs are highly adaptable for agile production in any size facility. If production cells are moved or new cells or processes are added, a new map of the building can be quickly and easily uploaded or the AMR can re-map onsite, so it can be used immediately for new tasks. This capability gives organizations full ownership of the robot and its functions. Rather than being constrained by inflexible AGV infrastructure, owners can easily redeploy the robot themselves as their business needs evolve to help them optimize production even in highly dynamic environments.

  • Expensive Vs. Cost-Effective

Although an AMR consists of much more advanced, intelligent technology than an AGV, it typically costs much less overall. An AMR does not need wires, magnetic stripes or other costly modifications to the building infrastructure, so it is faster and less expensive to get AMRs up and running, all without costly disruption to production in the process. Since AMRs can be deployed quickly and easily, they add new efficiencies almost immediately. With low initial costs and fast optimization of processes, they offer remarkably fast return on investment—often in less than six months.

Real Benefits

Metro Plastics initially set up the AMR to loop the production floor, stopping at each press for 30 seconds to allow operators to load finished products as soon as they fill a box. The robot then continues to the quality department in the warehouse where it automatically docks at its charging station until its next round through the production floor. By automating the transport of finished goods to quality assurance while jobs are in process, the company is also able to immediately identify and address quality issues, which helps reduce waste and drive competitiveness. The AMR has nearly eliminated fork truck traffic, making the production floor safer and cleaner.

As this example shows, depending on costly, inflexible technologies for automating material transport is inefficient and keeps companies from being competitive in today’s global business environment. AMRs offer an agile alternative to AGVs, manual delivery or forklifts, providing flexibility, productivity optimization and a strong return on investment. WMHS

Ed Mullen is Vice President of Sales, Americas for Mobile Industrial Robots (MiR), where he is responsible for establishing and managing the company’s distribution channels and marketing activities in the Americas. Mullen is a seasoned business development executive with more than 25 years’ experience in industrial automation sales management and engineering roles. Mullen holds a degree in mechanical engineering from the New York Institute of Technology. (www.mobile-industrial-robots.com)