500% pick rate rise – AGV vs AMR explained

If your business wants to reach the 500% pick rate rise that industry 4.0 makes possible, you need to understand the technology involved. An important step in that process is grasping the meaning of the terms.

Three letter acronyms are a common tool in describing advanced technology. With the notable exception of the World Wide Web, they are usually a much faster way of saying something complicated. However, when multiple acronyms are cover very similar subject matters, and they not well understood, and begin with the same letter, confusion often arises.

Such is the case with AMRs and AGVs. These two terms are widely seen and used in discussions of warehouse robotics. Often without full clarity on what differentiates the two, what the letters actually mean, and why it matters. That is why Wise Robotics is here to help.

What do AMR and AGV stand for?

An AMR is an

Autonomous

Mobile

Robot

And an AGV is an

Automated

Guided

Vehicle

Already it becomes clear why there is confusion. What is the difference between “automated” and “autonomous” and aren’t all robots “mobile” if they can move?

What is the difference between an AGV and an AMR?

The key distinguishing factor is the need for assistance with navigation. Specifically, how does the robot respond to the presence of an obstacle?

When an AGV encounters an obstacle, detected with one or all of its full array of sensors, it will sit there and wait and wait and wait. An AGV will not move until its pre-determined path is clear.

Should an AMR encounter an obstacle, it takes a very different approach. It will start off by waiting for a short while before it gets in touch with the RCS (robot control system) and asks for new instructions. The RCS, in collaboration with that robot, and all the other robots currently present on the grid, will calculate a new and optimally efficient path, taking the obstacle into account.

Guided vs mobile

The word ‘guided’ in an AGV’s name reveals why this is the case. An AGV will need some kind of external infrastructure to aid its navigation. This doesn’t mean it is anything like fixed automation from industry 3.0. The current generation of AGVs doesn’t need to be any rails or gantries or conveyors to manage their movements. However, an AGV may require things like magnetic strips built into the floor, or data matrix codes taped to the ground in strategic positions. If this guidance path is blocked or otherwise unavailable, the AGV cannot progress.

The ‘mobile’ in an AMR’s name refers to how it can move about freely from a preset path, able to adapt and readjust as need be. An AMR uses things like DM codes in the floor not just to guide it along the route, but to orient its position in a warehouse, so it can be re-routed and redirected as needs require.

To an AGV, a specific DM code might read as “continue progressing forward” whereas to an AMR a single DM code could say “you are at position X” and it’s own internal processing will know whether being at position X requires a turn or a stop or a progression forward.

While an AGV will use similar technology to an AMR for safety reasons, such as LIDAR to detect other workers, and ultrasonic sensors to scan for obstacles, an AMR will go one step beyond and use the sensors to build an entire model of the warehouse itself. This enables it to operate autonomously, rather than just automatically. AGVs require much more instruction from the RCS, and orientation from DM codes. AMRs are far less dependent on external information and systems.

Aren’t AGVs old technology?

Terminology around AGVs and AMRs gets even more confusing sometimes when it is talked about in the context of older waves of robotics. Many robotics providers will claim that AGVs represent an older generation of robotics from the time of industry 3.0. When robots would travel up and down giant gantries and rails and would need to use fixed infrastructure like conveyors and tracks on the floor to get things done.

In the most technical sense, these kinds of robots are AGVs because they are automatic, working without human intervention, and they move along a guided path – the rails or gantries or tracks that allow them to find their way.

However, the difference between AGVs from industry 3.0 vs industry 4.0 is this.

In industry 3.0, robots used external guidance to control their navigation. They are unable to move without them.

In industry 4.0, robots used external guidance to orient their navigation. They can move without them if need be.

The older model of robots had guide-rails because that meant it had only one path to move along. It could not physically move any other way.

An industry 4.0 AGV uses DM codes as a means of orienting itself and directing its journey. It has the capacity to move any number of directions it chooses but to find the most efficient and best possible route.

In the latter case, an AGV is far more flexible and adaptable than its fixed and infrastructure bound counterparts. It is able to choose directions based on current conditions, the arrangement of the other robots, the current storage situation, and the presence of any obstructions in the way of things.

What are the advantages?

In the bluntest possible terms, the biggest advantage is that AMRs are technically faster. This is because they are far less negatively affected by obstacles, able to re-route and reorient their operations much more effectively as needs require. AGVs can work very well in a robot-only grid environment, where minimal possible obstacles will ever arise. But should a robot breaks down, or a system changes somehow, the delays AGVs might experiance can stretch on and on.

AMRs are more useful for a more varied environment, where robotic operations cannot be confined to a single region, and other parties and obstacles may be frequently found entering the space. This is why they are often talked about in the context of manufacturing facilities, but also in hospitals and supermarkets, where the public at large need to be considered. In these settings, it is not enough to merely avoid obstacles. You need to be able to recognise them and factor their presence into your operations autonomously. This is what AMRs give you the option to do.

AMRs are also highly valuable to high-pressure warehouses. When throughput is under pressure, you need an automation system that can adjust and adapt as and when the situation requires. Without the fixed routes and strict procedures required by AGVs, AMRs are capable of a far greater range of tasks. As well as moving goods to picking stations, AMRs can also be rearranging goods according to operational projections and adjusting walkway needs as and when required.

When it comes to advantageous automation, the flexibility of AMRs offers many more options.

Discover industry 4.0

To learn more about what industry 4.0 is, what it means, and why it can create a pick rate rise of up to 500%, come and speak to Wise Robotics. Meet with us in person at Europe’s first flexible robotics demonstration centre.

When you understand the robotics revolution for yourself, you’ll understand exactly why it matters that your business responds sooner rather than later.