Maximum Wood Yield

A typical example for practical cutting problems is the problem of minimizing waste in sawmills, where boards of different grades and different dimensions are cut from logs.

Production of construction timber in the timber industry

In the production of construction timber, the raw product undergoes various processing and refinement stages, which end in its being broken down into ready-to-sale products.

Technological, geometric and monetary aspects have to be taken into account for this process. It is not always possible to convert the blank completely into products, but rather to produce unusable waste, which must be minimized.

For our customers we minimize this waste through the development of individual decision support tools which allow the evaluation of different cutting patterns with regard to technical (e.g. recycling volumes) and commercial criteria (e.g. revenues, saleability).

 

Multi-Criteria Optimization Problem

The main feature of the tool are derived rules with which Pareto-efficient saw patterns can be calculated when defining a multi-criteria optimization problem. For this purpose, we have developed a hierarchical enumeration algorithm that is basically able to enumerate all acceptable cutting patterns.

Specially developed cutting heuristics sort out the less promising cutting patterns so that only the most meaningful saw patterns are presented to the production planner. Compared to the tools previously used, our tool has increased the overall utilization rates by 0.5-3%.