Analysis of The Influence of Reference Dimensions On The Estimation of Gross Volume of Stacked Roundwood: A Case Study In Poland

Currently, a wide spectrum of solutions can be found on the technology market which uses photo-optical measurement methods for estimating the gross volume of roundwood stacks based on pixel recognition, stereoscopy, and LiDAR sensors. Therefore, the digital systems for roundwood measurements can be classified into two groups: 1) applications that require the use of a reference and 2) systems and applications that do not require the use of a reference. A reference is defined as a permanently or temporarily applied reference pattern on the front (and/or rear) side of the stack. Depending on the software considered in this study, a reference ranges from at least half a meter long to the width of the entire stack. The main aim of this study consisted of analyzing the influence of the: reference length on the gross volume of roundwood stacks. The following hypotheses based on this study (i) different volumes were obtained when using selected reference lengths; (ii) resulting differences were not significant from statical and practical points of view. A total of 30 pine industrial roundwood stacks were measured. Each stack was measured using the Timbeter app four times. For each measurement, a different reference length was used:1m, 3m, 5m and the width of the entire stack (W). The results showed that no statistically significant difference in volume within the tested reference length was observed. The highest volume was obtained for a 3 m length reference. Compared to other results, the resulting volume for that length was higher by approximately 0.2 m3 (st) (o.b.) compared to other results using the other considered reference lengths. From a practical point of view, the results of this study are crucial for the dedicated consumption time when using photo-optical measurement methods which require references.