Ulf Hallonborg
The Forestry Research Institute of Sweden, Uppsala, Sweden
Abstract
Certain properties of continuously advancing planting machines restrict their speed, thereby limiting their capacities. The cycle time of the planting device is predetermined by the design and is therefore difficult to alter. It is easier to influence the cycle timeof the seedling feed system, especially by changing the technical properties of the seedlings. In the case of pneumatic feed systems, air flow and hose diameter are also important physical factors. In cases where the seedling is not delivered to the planting device when required, the device will have to wait, and there will be a corresponding fall in productivity.
Consequently, it would be advantageous if we could predict the likelihood of such a delay occurring. To be able to do this, we need to know the statistical distribution of the feed cycle times for different combinations of the physical variables. One hypothesis is that feed cycle times exhibit a chi-square distribution. If this is true, future work should focus on developing transformations between physical properties and statistical parameters.
