Measuring soil surface and furrow profiles using a portable and affordable 3D scanner

Abstract

Abstract. Soil surface and furrow profiles in tillage and furrow opener research are usually measured using manual profile meters, and recently, laser and LiDAR-based scanners. Using manual profile meters could be laborious and time consuming, and their physical contact with the soil may impair readings. On the other hand, laser and LiDAR-based scanners are expensive and not portable. In this study, a portable and affordable 3D scanner attachable to a portable mobile device was evaluated for soil surface and furrow profile measurements. Results from the 3D scanner were compared to those of a manual pinned profile meter. Three boxes (dimensions: 400x400x400, 600x600x600 and 1000x1000x1000 mm, respectively) were used to specify a vertical distance for the 3D scanner above the soil surface and to block sunlight from the target area. The boxes helped assess the effect of vertical distance on the accuracy of measurement. It was found that the 3D scanner has the accuracy required for soil surface and furrow profile measurement to a depth of 110 mm. The device is potentially a cost-effective alternative to laser and LiDAR-based 3D scanners. The effect of the 3D scanner‘s vertical distance (above the soil surface) on accuracy was not significant. For increased accuracy in the measurements, the soil surface needs to be well-levelled; this may be only possible in soil bins. Boxes of dimensions 600x600x600 and 1000x1000x1000 mm are recommended for easy handling and provision of adequate soil surface coverage, especially in furrow opener studies.