Low-Cost Grain Moisture Meter System Networked to Smartphones
Accurate moisture content measurement is one of the key quality factors listed in grain trade. It is important in determining whether a crop has been dried properly for safe storage and marketing, and it is used by buyers and sellers of grain to estimate the value of the commodity. Unfortunately, many farmers and grain originators in developing countries cannot afford to buy moisture meters and utilize them to routinely determine whether their crops are dried for safe storage, and thus incur huge losses along the value chain. Additionally, farmers are at a disadvantage in trading to high-ended markets, which have high quality standards and need verification that the commodity purchased has been adequately dried. This thesis work involved the development of a low-cost grain moisture meter that is composed of a separable grain sampling cup (sensing cup), a data acquisition circuit (moisture meter device) and an Android app that networks the moisture meter device with smartphones. The grain sensing cup is based on a parallel plate capacitor that can be sealed and unplugged from the moisture meter device, when it is required to verify the integrity of the sample. The moisture meter device allows the moisture measurements to be captured, displayed and data sent wirelessly to a smartphone. The mobile Android app was designed for data capture with the goal of facilitating market transactions related to commodity trade, financing and traceability. The system was calibrated for soybean and corn using the low moisture content range to compute the models. The calibration performance evaluation showed that for corn, the device complies with the NIST standard for a wide range from 12% to 27% mc with an accuracy of 1.1% mc and a resolution of 0.66%. For soybean, the device complied with the NIST standard from 10% to 19% with an accuracy of 0.76% mc and a resolution of 1.25% mc. The findings of this study and the technology developed will enable smallholder farmers achieve better grain quality, enable traceable from origination to processing, and thus open a market opportunity for them in more lucrative bio-secured markets. Intellectual property (IP) protection is being sought through Purdue Research Foundation Office of Technology and Commercialization (OTC).
Ileleji, Purdue University.
Off-Campus Purdue Users:
To access this dissertation, please log in to our