Suzhou Jutong Automation Equipment Co., Ltd. (hereinafter referred to as Jutong) is one of the earliest professional logistics conveying system integrators in China, specializing in the planning and implementation of modern logistics conveying systems. Among its products, automobile tire production lines are one of Jutong's main offerings.
Tires travel through multiple locations, factories, cities, and countries throughout their lifespan; therefore, accurate tire identification is crucial for managing compliance, work-in-process, sorting, process routing, and quality control. Quality control and traceability are fundamental requirements for tire manufacturers. Tires need to be tracked at every step of the production process, from logistics and work-in-process to quality control and verification inspection. From raw materials to tire assembly and end-of-line sorting, reading barcodes is essential in the tire industry.
However, reading barcodes in the tire industry is a very challenging task. Not only does it require reading the barcodes from all angles, but the quality of the barcodes also degrades during the production process.
The challenges of barcode reading are: the tire industry affixes 1D CODE128 vulcanized label barcodes to any area within the tire's radius; tire codes are relatively small and narrow, typically around 10 mils; the all-black surface of the tire absorbs light; the quality of the tire barcode decreases during the vulcanization process, and the contrast between the code and the background is usually very low, making the barcode prone to wear; because the moving barcode can be in any direction within the inner diameter, the visible field of view is quite large; and the code is read through a very small gap under the roller.
Therefore, failure to apply the correct and efficient scanning technology can lead to a loss of productivity, increased manual processing, and additional compliance management costs.
Jutong Company has previously used Datalogic barcode readers, with five readers per group, to read the barcodes on tires. Due to the small gaps between the rollers, barcodes were not fully read when they were underneath, resulting in a consistently low read rate. Furthermore, the readers were expensive, so they were rarely used in this application.
“When using previous barcode readers, we found it difficult to seamlessly connect them to the Rockwell EtherNet IP bus used to operate the machines,” explained a technical engineer from Jutong Company. “Programming the PLC to communicate with the previous barcode readers presented considerable challenges. The programming required extensive knowledge of the barcode reader's proprietary interfaces and involved very time-consuming manual coding. Any changes to the production process necessitated modifications to the PLC code communicating with the barcode readers.” Therefore, Jutong Company urgently needed an advanced and efficient barcode reading technology to solve these production difficulties.
“I learned from the exhibition that Cognex’s current barcode readers use Hotbars2 technology to achieve a larger DOF and FOV, and Cognex is a global leader in the vision industry,” said Manager Mao of Jutong’s new project introduction department. “After communication and negotiation, Cognex recommended Suzhou Zhuoyue Jinma Electronic Technology Co., Ltd. (hereinafter referred to as Zhuoyue Jinma Company), which has been cooperating with them for a long time. Afterwards, Zhuoyue Jinma Company conducted a lot of testing and research for this technical transformation project, and finally decided to choose Cognex’s powerful DM363QL to help us solve the tricky problem.”
The DataMan barcode reader integrates relatively easily with PLCs used to control production lines. It features an Ethernet interface for connection to the factory network, enabling communication with all other devices on the network. For the ETHERNET IP industrial Ethernet protocol supported by Rockwell PLCs, the DataMan reader also comes with a manual, ESD file, and sample codes.
By using the ESD file provided by the barcode reader and the Ethernet/IP standard, it is easy to connect to PLCs and other common factory automation equipment. The steps are as follows: First, load the ESD file into the Rockwell programming software. The ESD file is an Ethernet IP configuration file used by network configuration tools to help identify products and debug them on the network. Then, the ESD file assigns a tag to the barcode reader, which contains the reader's unique name and IP address. The final step is to define the input and output nodes. Then, the engineer writes the application according to the relevant code in the manual and defines the relevant logic.
The operating procedure of the barcode reader and the conveyor belt is as follows: When the tire is transported from one end to the outbound section, DataMan senses the tire signal through the sensor and transmits it to the PLC. The PLC instructs the barcode reader to collect and read the image.
Engineers tested the DataMan363QL barcode reader + HPIA on the tire conveyor belt production line. Three DM363QL units were networked as a master-slave below the conveyor belt to transmit data to the control room 100 meters away, successfully completing the code reading task.
Moreover, the on-site engineers were surprised to find that, even with very low contrast, severe distortion, and very high speed, when trying to read barcodes with a Cognex barcode reader, the DataMan barcode reader was able to successfully read the codes in all these situations.
"By adopting the image-based DataMan barcode reader, we have successfully solved the cost problem of multiple barcode readers. We only need three to meet our reading needs," a technical engineer from Jutong Company pointed out. "Furthermore, the image acquisition speed is faster, resulting in a high reading rate under the track and more efficient use of pixels."
They found that using Hotbars2 technology increased the conveyor belt coverage area by 20% because Hotbars technology can reliably read codes to an accuracy of 1.2 PPM instead of 1.5 PPM; image acquisition speed is 20 times faster than the 1DMax algorithm; and even with 100% redundancy, fewer cameras can be used.
“Cognex’s Hotbars2 technology, with its flexible accessories, allowed us to excel in this tire code reading upgrade project,” said a technical service engineer from Excellence Code. “We are pleased with Cognex’s product strategy, which improves reading performance, reduces installation time, and offers competitive costs. The Cognex Extended Solution also supports code reading applications for more efficient image acquisition and minimizes read failures, which will undoubtedly increase throughput and productivity while reducing costly rework.”
Ultimately, Jutong Company achieved efficient reading of tire barcodes by adopting Cognex's DM363Q vision reader with an HPIA light source. This not only significantly increased production speed but also improved the product manufacturing process and promoted overall product quality enhancement.
“Fewer barcode readers mean fewer points of failure, lower overall cost, and easier installation and troubleshooting,” summarized Manager Mao from the New Project Introduction Department of Jutong Company. “The read rate is basically around 99.99%. Utilizing HotBars 2 technology, even if the barcode is distorted or damaged, especially when reading under a track, the DataMan barcode reader still has excellent reading performance. Field practice has proven that Cognex’s technology can achieve higher reading performance with fewer cameras.”
