Calcmadeira: Software for Estimating Lumber Production
One information that is generally not used but is still essential to the economic evaluation and wood yield of the sawmill production chain is the quantification of lumber a priori. The few applications that provide a solution to this problem work with one log at a time and generally use optimization techniques instead of cut pattern models. The software developed for this work uses trigonometric rules, applying the circumscribed square (block), longitudinal (or tangential), log rotation, and radial cut patterns to help a producer sell a tree not in cubic meters but as a function of the pieces obtained from trees. Six tests were performed using trees and individual logs. The comparison between the calculated and milled or drawing pieces was presented for each model. The total errors obtained were approximately 2% for priority pieces. The best accuracy for the number and volume of the lumber pieces was 2.2% and -5.4%, respectively, obtained with a 30o angle of the slab (waste wood) and 0.60 to the proportion of the radius parameters in the model that rotates the log. The total calculated and observed piece width distributions were statistically equal in the radial model. This application requires observation of the milling operation while monitoring parameters in a heterogeneous sample of wooden logs to obtain the best results.
