Estimating soil texture with laser-guided Bouyoucos

Abstract

The main objective of estimating soil texture is to determine amounts of components of the soil. While the analysis of coarse particles is performed by sieving, Bouyoucos-hydrometer method is used to determine percentages of small particles (silt and clay, also sand). However, these traditional methods require expertise, laboratory environment, sensitive equipment and a long-time period. All of these requirements are overcome by “Laser-Guided Bouyoucos” which is proposed in this study. The proposed device estimates the amount of components of soil by passing laser light through the beaker and evaluates the changes in the magnitude of light. Besides, the device requires no expert or laboratory medium for measurements, can be built using easy-to-find and cheap equipment, and most importantly, can be mobile for in-situ use. Several soil samples preanalysed by Bouyoucos-hydrometer method are used in this study. The error of the proposed device was calculated by summing the absolute errors of sand, silt and clay components, and the average of all errors is only 2.25%. Although more soil samples are needed to test the system, according to the successful results on the used dataset, we believe that soil texture can be analysed quickly without an expert or a laboratory.