Simulation Modeling of Truck Load of Skidding Tractors with a Grapple for Chokerless Skidding

Abstract

The objective of the present study is to define mass distribution laws for a bundle of trees using the methods of statistical simulation modeling in order to calculate chokerless skidding tractors lift capacity. For that purpose a statistical simulation model has been developed to generate forest taxation data necessary for complete filling of skidding tractor grapple. The following samples have been obtained from the regions of the European North of Russia based on the model: masses of bundles of trees that can be placed in grapple and values of vertical component of normal load applied to skidding tractor grapple. Minimum values for masses of bundles may vary in the range of 40-87% from the average value. Maximum values may vary in the range of 8-55% from the average value. The difference between the maximum and minimum masses of bundle values increased with increasing the capacity grapple and decreased with increasing the distance from the butt to grapple. We have determined the dependence of bundle mass variation and values of vertical component of normal load applied to skidding tractor grapple on capacity grapple for the regions of the European North of Russia. The studies have allowed determining recommended values for chokerless skidding tractors lift capacity. The analysis of specifications of various models of skidding tractors has shown that clambunk skidders have deficient marginal lift capacity.

Basics of Forest Ecology and Management

“…Tractors and prime movers (skidders) have the dominant position in ground-based timber skidding (Shegelman et al, 2019). They primarily operate in tractor terrains (slope up to 40%).…”

Design of pedestal for mounting of hydraulic grapple on skidder

“…Timber logging can be defined as transposition of logs form a place of harvesting to a place of timber processing or timber transportation. Ground yarding is most often used for slopes up to 40 %, but some logging tractors are able to work on slopes even up to 50 % [1][2][3][4]. DOI:10.22616/ERDev.2020.19.TF058…”

The Impact of Weather and Slope Conditions on the Productivity, Cost, and GHG Emissions of a Ground-Based Harvesting Operation in Mountain Hardwoods

“…Typically, the productivity of harvesting operations can be influenced not only by the choice of equipment (machine type, operator skill, functions), but also by many other variables that are also important. Among these variables are terrain (i.e., the slope gradient), stand (e.g., stump diameter), environmental (e.g., weather), and yard (e.g., winching distance) variables [5][6][7][8]. Indeed, the cost of a ground-based harvesting operation (felling and off-road transportation) constitutes more than 40% of the total wood supply chain cost [9,10].…”