Desenvolvimento de um medidor de vazão para fertilizantes sólidos

Abstract

The application of metering mechanisms is fundamental for the agricultural scene, in a scenario in which, inputs are indispensable for the production. Agricultural producers look for a satisfactory productivity for market competitiveness and at the same time, sustainability. The objective of this work is the construction of a mass flow measuring device that is capable of measuring the mass flow of solid fertilizers that will be applied at variable rates, thus controlling the need of the soil and making the fertilization process more precise, sustainable and economic. In the development of this work, the performance of two different principles for the fertilizer dosage were analyzed and tested, and, subsequently, the principle with better performance was selected through an evaluation in terms of precision, applicability and efficiency. The techniques studied were that of an electromagnetic induction flow meter through coils and that of a flow meter using photodetection. Parallel to the analysis of the possibilities of sensing and subsequent to the choice of the best technique, the digital data processing firmware was developed, which was performed through a microcontroller. The sensor constructed counts the passage of fertilizer granules through an external interruption with exit edges, finally, the amount of granules information is converted to grams before being made available.