Dynamic Control of Timber Production at a Sawmill with Log Sawing Optimization

Today most sawmills use optimization techniques to maximize yields from logs. If open market conditions are assumed when maximizing volume or value yields, overproduction of some products and underproduction of others may result. In this study, a system is described that links production with log sawing optimization while also addressing demands for timber products of differing qualities. The system is based on an optimization framework that is implemented in a log sawing simulator, AUTOSAW. Unlike other optimization systems that use static product ''values'' such as board volume or timber price, dynamic values are used that are updated regularly according to previous timber production. The efficiency of the system was tested with three orderbooks via comparisons with volume- and value-optimized solutions obtained from sawing pruned Pinus radiata D. Don logs. In each case, product optimization required fewer logs to satisfy all demands than did either volume or value optimization. Furthermore, underproduction was eliminated and overproduction reduced.