A pre-cast element factory in Liepaja manufactures approximately 100 elements (hollow-core slabs, precast walls and columns, staircases) in a single day. All the manufactured goods are stored in 10’000 m² warehouse next to the manufacturing plant. The warehouse is divided in multiple named zones to easily locate the final production when it is necessary.
When a pre-cast element is manufactured it is move to one of the zones in warehouse. The zone name is registered and entered in manufacturing planning information system (ALTO 4.0 ERP) manually. It is an error-prone and time consuming job – loaders have to make a hand written note for each element and then managers have to enter this information in system’s database.
To simplify and reduce the workload of company’s employees ALTO 4.0 decided to implement barcodes for each element and scanners that would scan element information, storage zone and send it to the system automatically. This project would be a pilot-project for similar systems in UPB holding has 5 other manufacturing plants with their respective warehouses that would require similar scanners to track inventory, statuses of manufacturing or building etc.
Main requirements for such a project were determined:
- Barcode should be read quickly in any light conditions. Loading in warehouse happens during the nights.
- System must work wirelessly – pre cast element warehouse is 10’000 m² they have to work everywhere within that area
- Scanners must be rugged – must work in any weather conditions (-15°C – + 30°C), it can be dropped on concrete.
- The scanning application should be as simple as possible (scan zone, scan element and send)
- Prepare the ALTO 4.0 ERP to work with scanners – The ALTO 4.0 ERP needed additional API feature to send the information of element placement to the ALTO 4.0 ERP.
- Prepare barcodes for each element – UPB already used labels on each element that contained information about it. So we only added barcodes to the labels.
- Develop scanner software to send the data to the system. This is in-house task that our developer team did in cooperation with manufacturing plant managers.
Choosing the hardware
First we tested a usual android based phone and ZXing scanner library. It turned out to be unusable in our conditions – often the barcode was read incorrectly and it was not possible to read the barcode in bad lightning conditions at all.
Second we continued with specialized barcode scanners. . In co-operation with the DENSO Auto-ID Business Unit of TT Network Integration Europe we acquired a sample device of DENSO BHT-1400 scanner. Although it works great as a scanner and it fulfilled our requirements we decided that Windows CE OS would not be the best choice for future development.
While looking for scanners with more modern OS we decided to choose Android based scanners. Because it is more commonly used OS, more developers are working on Android and it is easier to maintain applications based on Android. DENSO offered us to test their new DENSO BHT-1600 Android scanner.
It fulfills all our requirements for a scanner: It is robust with a ruggedized case, scanning works quickly and reliably, programming API is simple, and we can use the mobile data to connect to internet for sending scanned data to ALTO 4.0 ERP.
We developed the Android app in-house to be as simple as possible – it reads data from ALTO 4.0 ERP about the warehouse and it’s zones, user selects or scans the zone ID and then scans element id to the zone.
Additionally the application sends current GPS coordinates when the element was scanned to the ALTO 4.0 ERP. We used this feature for testing purposes to see whether it is possible to use this info to locate scanned elements by coordinates rather than the warehouse zones. We mapped the locations of scans on the map of the warehouse and noticed that some of the scanned elements are way out of their actual location due to GPS errors.
We have made a simple scanner application and tested it in our pre-cast element manufacturing plant. As it was a pilot-project of barcode scanning capabilities we chose the simplest option to implement – scan a barcode and send the data to ALTO 4.0 ERP. As the results and feed-back from managers and users is great we plan on implementing more scanning applications in the company in near future (for assets tracking, materials usage, manufacturing status tracking etc.) The DENSO BHT-1600 scanner works great during the testing in our manufacturing plant.