MODEL-BASED VERIFICATION OF A PENDULUM-ARM SUSPENDED FORWARDER FOR SUSTAINABLE FORESTRY

摘要

Cut-to-length logging (CTL) is a mechanized harvesting process where trees are delimbed and cut to length directly at the stump. CTL is typically a two-machine operation with a harvester felling, delimbing, and bucking trees, and a forwarder transporting the cut logs from the felling area to a landing area that is accessible by trucks, or trains. A major challenge for the manufacturers of forestry machines for CTL logging is to (1) further increase the harvesting and log transportation productivity, e.g. by enabling operation with higher transportation speed and on eco-soils, (2) reduce the damage to the soil, e.g. by controlling the rut depth and preserving the root layer, and (3) reduce the daily vibration dosage for the machine operators, e.g. by active chassis and cabin suspensions. This paper presents a study of a novel all-wheel-drive pendulum-arm suspended medium-sized forestry machine, with several upgrade performance steps, e.g. passive and active chassis suspensions. The dynamic performance of the new concept are quantified with simulations and compared with a present bogie solution. The simulations show an 80% reduction of whole body vibrations with an active suspension system compared to present passive bogie solutions when operating on a standardized test ground.