Energy consumption of selected tree shakers under different operational conditions

The fundamentals of shaker design and the analysis of the tree as a vibration structure were mostly worked out in the 1960s and 1970s. At the same time, the main problem was always the accurate determination of effective masses reduced to the clamping point. Further deviations and errors were caused by the assumption that the restoring force is simply proportional to the displacement. The effect of attachment height on the various parameters of the system was not examined at all. In this study, a new tree model is introduced allowing three different kinds of trunk motion. Based on acceleration measurements in the soil body, a new mass component is included to the common mass components. An analysis of dynamics and power requirement of the system has shown that the elastic deformation of the trunk will continuously be higher as attachment height increases, resulting in a significant decrease in the net power requirement. (C) 2001 Silsoe Research Institute.