Konstruktion av timmergrip

The gripping arms of today’s grapples follow a circular motion which means that the grapple must be lowered or heightened continuously by the operator to avoid that the timber is missed or that damage of the ground surface occurs. Because of this LIAB (Lima Innovation AB) wants to examine the possibilities to construct a new grapple that solves this problem. The goal of this thesis work is to construct a grapple, which fits existing forwarders, that minimizes the digging motion. Throughout the project a product development process, elaborated at Luleå University of Technology, called Sirius Masterplan has been followed. The use of, among other things, motion- and FEM-analysis has resulted in solid models of a grapple that, with the aid of four bar linkages, performs a close to linear motion along the ground. The remaining performance of the grapple is equivalent to those of competing grapples. These solid models will be used to manufacture a prototype that will be tested and evaluated during real life conditiValiderat; 20110220 (anonymous