IO-Link is the future of sensor data transmission. The technology is already standard in pressure, temperature, level sensors and the like. In image processing, however, the situation is different: Many users have reservations that IO-Link is reaching its limits due to the large data volumes and low data rates. The O2I multicode reader from ifm shows that IO-Link has a future in image processing.

It is not without reason that the IO-Link communication system has made a triumphant advance in industry. The technology combines simplicity with reliability. The structure is also relatively easy to explain. The system contains various sensors and actuators that are connected as so-called IO-Link devices to a master via the technology, which in turn represents the interface to the higher-level controller. This makes it independent of the controller and fieldbus. The standardized IO-Link simplifies both installation and maintenance. If a temperature sensor fails in the food industry, for example, it can be quickly replaced and the parameterization transferred to the new sensor; plug & play is therefore no longer a vision of the future. IO-Link delivers the exact measured values to the controller without interference and allows transparent remote access to the sensor parameters. In addition to the process value, secondary information can also be retrieved from the sensor and processed. The result is a Y-path that transmits the process value to the controller while also sending sensor-specific diagnostic data and memory values to an IoT controller via the master. Condition monitoring and predictive maintenance are also facilitated via the communication system. However, IO-Link still has a problem that makes it difficult to use in some fields of application. The protocol offers three different speeds: 4.8, 38.4 and 230.4kBaud. This is completely sufficient for the transmission of conventional sensor data, but not for the transmission of process data that can be generated by image processing. Nevertheless, the trend towards IO-Link does not stop at vision systems. With the O2I multicode reader, ifm shows how IO-Link can already be used in image processing.

Multicode reader for code & text
The multicode reader enables the evaluation of different 1D/2D codes and texts in a single image. This is relevant in different phases of the production process, and logistics in particular benefits from the technology. The O2I checks the quality of codes and text information or ensures product tracking along the entire production process. The reader is also equipped for use in production environments that are often dark or shaded. The integrated RGBW lighting can be adjusted so that the reader reliably detects even difficult color combinations between code, text and background.

The O21 benefits from IO-Link in several ways. It uses the COM3 standard with a speed of 230.4kBaud for data transmission. For better transferability, data larger than 32 bytes is automatically divided into several blocks and thus transferred quickly to the controller. The data blocks are separated automatically and the hold time can be set individually. This has the advantage that no special function blocks are required in the control system. In addition to transmission, IO-Link also makes handling the multicode reader easier. Users can install the sensor directly into the existing system infrastructure. The reader is set via a teach button and is ready for operation within a few seconds. It is aligned with the code and then automatically performs focusing, code type detection and exposure adjustment. If you still need to process more complex tasks, you can also use the Ethernet interface at any time. The basic configuration is possible via a special smartphone app, which can also be used to set triggers or the IP address. The smartphone then generates a data matrix code, which is held in the O2I's field of vision. The sensor automatically adopts the configuration stored in the code.

Configuration via wizard
Configuration via the smartphone app is not the only way to set up the multicode reader. With the ifm Vision Assistant software, the company offers a tool for professional users in the industry with which the sensor can be configured even more extensively. using various logic functions, they program the sequence control within the sensor, eliminating the need for an external evaluation unit. The O2I also independently recognizes several different codes in one image. the codes can be easily assigned via the Vision Assistant. A live image and visualization of the settings allow users to maintain an overview at all times.

Conclusion
The O2I multicode reader from ifm is proof that image processing and the advantages of IO-Link in order picking and results transfer are by no means mutually exclusive. Ifm is convinced that even with the limited data rate compared to Ethernet and fieldbus, applications can be implemented simply, quickly and reliably - even in applications with vision sensors.