Browsing by Author "Siljander, Tomi"

Soil structure is one of the key elements when it comes to plant growth and yield production. For the last 30 years, the agricultural machines have grown in size, which has increased the stress to soil caused by the machinery. When the stress is high enough to increase the strengths in soil, and the porosity and permeability are decreased, the soil is compacted. There are some soil scanners, which are capable of mapping the soil strengths. The aim of this study was to use the draft data from the CAN bus in this purpose. The topsoil strength data could be then used as part of precision agriculture,for example in problem solving with low-yield areas, and as part of variable depth tillage purposes. The goal for this study was to build a measurement system, which could record the draft data of a tractor and also to find out the usability of this data in precision agriculture. Measurements of the reference data (electric conductivity, organic matter) are also part of this study, which included initialization of the Veris iScan+ and also the development and building the subframe for the scanner. As the measurement system Raspberry Pi minicomputer equipped with CAN bus and GNSS boards was used. The measurement system was programmed with Python programming language. In the measurements, a Valtra N141 tractor and a Kverneland Turbo 2 cultivator were used to tillage the two-hectare test plot. After the measurements, MATLAB and ArcGis were used for processing the raw data, mapping the features, and analysing the data. In this study, the implement draft was found to be significantly higher in the headlands of the field, which face the most field traffic. In the test plot, there were three individual zones with high draft force values, each resulting from different reasons. These zones were visible in the EC and OM maps, but all of the draft force variation could not be explained by the reference data. According to this study, the CAN bus draft data could be used as topsoil strength indicator, and with the right reference data the draft data can be used to map the topsoil compacted areas.