Our interest in inventory management stems from observing many operations in Sub-Saharan Africa, including collection of field specimens for scientific projects, distribution of farm inputs by suppliers and wholesalers, and financial accounting for retail stores. In all cases, there is a need to precisely trace the movement of goods being stored and forwarded from one relay point to another, such that managers can query the integrity, count, and location of any product undergoing shipment in real-time. This basic functionality is missing from many logistics operations, often because the need to support them with rigorous data management systems is not realized until much later, when evidence of fraud or product mishandling is exposed.
We have been developing solutions for managing physical inventory and supply chain networks through the system illustrated above, named AIMS: Asset Inventory Management System. This system applies small, unique digital identifiers to all inventory, such as QR codes or RFID codes depending on budgetary constraints. We can equip operators with Android mobile applications for recording the space-time coordinates of every parcel along its way, and syncing this information to a centralized web server, where managers can easily oversee and visualize their supply chains.
Below we describe some components of AIMS in further detail, whose usage has been demonstrated in several scientific projects for the gathering of soil and crop information.
The Tag software application enables projects which cannot afford RFID technology to pre-print randomized QR codes to serve as identifiers. The app can conform to a wide variety of user specifications garnered from extensive user feedback, such as:
In addition to paper media, we can also support projects willing to invest in more rugged materials, such as laminated badges made from PVC plastic.
As barcoded specimens/products are ferried from one relay point to another, Android apps can be used to upload updates about inventory status, providing managers with larger windows of transparency.
The Mobilesurvey application provides an example of software we have been supporting to georeference field specimens and visualize their acquisition. When specimens are acquired in the field, they are bagged and tagged with the aforementioned QR codes, and the ODK Collect Android app is used to scan these QR codes and record metadata such as the location, time, field operator handling the specimen, and any relevant information about the surroundings. This data is cached and automatically uploaded to the cloud once WiFi returns, while scalable geospatial visualizations are provided in the browser to managers overseeing operations. Our system also provides clues to possible fraudulent activity by auto-identifying sampling locations that deviate too far from the original plan. Since July 2015, field teams for AfSIS, TanSIS, and TAMASA have been using this tool to conduct ODK-based surveys for soil and crop analysis.