Prediction of basic timber properties like moisture content and density is an important factor for quality control in timber industry. This paper deals with the detection of moisture content and density of spruce (Picea abies). It describes the calibration and validation of the newly developed microwave prototype on the basis of 480 measurements for moisture contents between 8 and 19% and densities between 340 and 600 kg m–3. The calibration and first validation set lead to R2≥92% in both cases. The prediction for a second and third validation decreases as especially the range of moisture content for these pieces was limited. Compared to other moisture and density measurement systems, the prototype showed good performance. With this technology it is possible to detect moisture and density of a piece of timber contact free and non-destructive with high prediction accuracy for both parameters in one pass.
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