DEVELOPMENT OF A HYBRID UAV SENSOR PLATFORM SUITABLE FOR FARM-SCALE APPLICATIONS IN PRECISION AGRICULTURE

Today’s modern precision agriculture applications have a huge demand for data with high spatial and temporal resolution. This leads to the need of unmanned aerial vehicles (UAV) as sensor platforms providing both, easy use and a high area coverage. This study shows the successful development of a prototype hybrid UAV for practical applications in precision agriculture. The UAV consists of an off-the-shelf fixed-wing fuselage, which has been enhanced with multi-rotor functionality. It was programmed to perform pre-defined waypoint missions completely autonomously, including vertical take-off, horizontal flight, and vertical landing. The UAV was tested for its return-to-home (RTH) accuracy, power consumption and general flight performance at different wind speeds. The RTH accuracy was 43.7 cm in average, with a root-mean-square error of 39.9 cm. The power consumption raised with an increase in wind speed. An extrapolation of the analysed power consumption to conditions without wind resulted in an estimated 40 km travel range, when we assumed a 25 % safety margin of remaining battery capacity. This translates to a maximal area coverage of 300 ha for a scenario with 18 m/s airspeed, 50 minutes flight time, 120 m AGL altitude, and a desired 70 % of image side-lap and 85 % forward-lap. The ground sample distance with an in-built RGB camera was 3.5 cm, which we consider sufficient for farm-scale mapping missions for most precision agriculture applications

Comparison of risk in organic, integrated and conventional cropping systems in eastern Norway

The aim of this study was to compare risk of organic, integrated and conventional cropping systems. Experimental cropping system data (1991-1999) from eastern Norway were combined with farm budget data. Empirical distributions of net farm income for different cropping systems were estimated with a simulation model. The results show that the organic system had the greatest net farm income variability, but both the existing payment system and organic price premiums make it the most economically viable alternative

Criteria for describing decomposition of plant materials in a dynamic simulation model

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Characterisation of plant residue quality for prediction of decomposition and nitrogen release in agricultural soils

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