How To Choose The Right Technology For AGV Navigation

2023 Author : Hannah Pearcy | [email protected] . Last modified: 2023-05-24 11:12

All roads lead to Rome, an old saying goes. Applied to driverless transport systems (AGVs) and the various navigation technologies available, this means that each of these technologies leads an AGV to its destination - however, not every one is the most suitable for the respective application.

Different processes and technologies

There are different procedures and technologies to navigate an automated guided vehicle system from A to B:

• Contour navigation (natural navigation)
• Laser radar
• optical or inductive tracking
• or raster navigation .

Which technology is used in an AGV mainly depends on the specific application. The price of the AGV itself can also be used as a rough guideline. The costs for the navigation technology should not exceed 5% of the AGV price. For example: Contour navigation and laser radar are generally out of the question for a 10,000 EUR AGV, since their costs are above the threshold of 500 EUR.

Take into account the type of vehicle

Another decision criterion: is the AGVS an undercarriage or platform vehicle? AGVs are referred to as undercarriages that drive under the load to be transported and pick it up. Due to their structure, they are not suitable for laser radar, for example. In turn, loads are pushed onto platform vehicles. Here the cargo is transported on the vehicle.

For which applications are the various navigation options best suited?

Contour navigation is also known as "natural navigation" in the Anglo-Saxon language area. These are the most technically complex and expensive navigation systems. They are characterized by unrivaled flexibility and accuracy.

If the route has to be changed at short notice, this is very simple and quick with contour navigation by clicking the mouse in the higher-level software, the so-called fleet management. Since the sensor on the AGV is usually located at a short distance from the floor, this navigation variant is suitable for automatic forklifts and tractors, for undercarriage or platform vehicles. This type of navigation does not require any additional aids such as reflectors, optical or magnetic tracks, and markings or codes.

Driverless transport system

Consistently modular and maintenance-friendly design

Navigating with laser radar is just as flexible as contour navigation. However, this navigation variant always requires an additional optical connection between the sensor and the reflectors. That is why the sensor on the AGV must be mounted so high that it has a clear view of the refectors at all times. If the connection to the reflectors is interrupted, for example when entering a rack aisle, the AGV must switch to another type of navigation. This makes it difficult to move to another room, if necessary, and limits flexibility.

Always look

The optical and inductive track guidance are usually very simple systems, which follow a fixed track. This severely limits their flexibility. On the other hand, they also represent a very cost-optimized solution. Since the sensor is attached to the AGV at a short distance from the ground, this type of navigation is independent of the vehicle type selected.

In numerous warehouses and distribution centers, but also in many production environments, contamination is no longer a real problem, so optical systems are a good alternative. These are often much easier to set up or adapt. Optical variants that follow a line are particularly flexible because the line can be easily applied or changed.

New sensor for optical tracking

A new technology based on contrast detection is the new sensor for optical guidance OGS 600 from Leuze. Thanks to its edge detection and the sending of control signals to the steering motor, the track can be guided optically so that driving can be automated easily can. The detection width of the sensor ranges from 140 to 280 mm on an exposed adhesive tape with line and contrast trace. With the usual simple vehicle interfaces, it is suitable for use in AGVs of all sizes. Thanks to its compact design and the small minimum distance from the ground of 10 mm, it can even be integrated into flat vehicles.

With the OGS 600, Leuze is introducing a new sensor that enables cost-effective automation of vehicles for the transport of materials and goods in the production and storage area. Thanks to its edge detection and the sending of control signals to the steering motor, the track can be guided optically so that driving can be automated easily. AGV routes can be flexibly adapted.

Compact and close to the ground

The compact design of the OGS 600 and its small minimum distance from the ground of 10 mm enable it to be integrated even in flat vehicles. Variants with different detection widths and response times offer a wide range of applications, even with tight bends and high driving speeds. The parameterization and interface integration is carried out via the Sensor Studio software. An assistant analyzes the contrast between floor and track individually and recommends the best possible track color. A high level of functional and ambient light security is provided, as is quick commissioning thanks to a simple address setting.

Author Matthias Göhner, Industry Management Intralogistics at Leuze, shares the vision of an intelligent production (Smart Factory) in which manufacturing plants and logistics systems will organize themselves in future without human intervention. Continuous conveyors and driverless transport systems (AGVs) handle logistics orders independently and navigate automatically.

Last but not least: In the so-called grid navigation , information such as 2D codes or transponders is embedded in or onto the road in a predetermined grid. With the aid of the information determined when the individual grid points are passed over - in the case of a 2D code, the data and reading angle stored in the codes - the AGV can navigate between the individual grid points and approach each predetermined point within the grid. This type of navigation is particularly suitable for clean and less stressed documents.

A general assessment and recommendation for the suitable navigation variant can only be made in connection with the function of the AGV within the respective application. At the moment, however, there is a clear trend towards contour navigation with an integrated safety function. (jv)

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Book tip

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* Matthias Göhner, Industry Management Intralogistics, Leuze electronic GmbH + Co. KG