The Dynamics of the Forest Crane During the Load Carrying

Abstract

In this paper, the theoretical and calculation model of the forest crane and the lifted load is presented. The model enables the simulation of the motion of the load carried by a forest crane while taking into account the elastic deformations of the boom. The lifted load has been modeled as a 3D rigid body. The application of such a load model enables the simplification and enhancement of the calculation algorithm. The equations describing the coupled motion of the system load and machine elements are presented. The kinematic model enables the analysis of the basic motion of the load as a response of the system to operational control of the forest crane. In order to determine the motion parameters it was assumed that all system elements are rigid. The lifted load is also treated as a rigid body and its motion is the result of the movement of the load suspension point and the dynamic interactions generated during the motion of the system. The presented sample results from the numerical calculations were obtained from the Matlab system. The initial problem has been solved by the Runge–Kutta method. The numerical program has been developed on the basis of the presented model which allows analyzing the motion of load arising from crane operating mechanisms.

Impact of Wind on the Movement of the Load Carried by Rotary Crane

“…The literature on the subject lists a series of works pertaining to the problem of modelling crane dynamics; optimization of their work cycles; or influence of external forces. The problem of crane dynamics with the inclusion of various load transportation processes was presented in Works [1][2][3]. Paper [1] presents a dynamic model of a mobile crane and a carried load in which the flexibility of the support system was taken into account.…”

“…In addition, the article provides the mechanical-mathematical model with the use of Lagrange's equation of the second order. In Work [3], the theoretical and computational model of a forest crane and carried loads was presented. The numerical program, which has been developed in this work, allows analysis of load motion resulting from a crane's operating mechanism.…”

Stability Assessment as a Criterion of Stabilization of the Movement Trajectory of Mobile Crane Working Elements

“…Carrying large loads with the aid of truck mobile cranes may in certain conditions lead to a stability loss [1][2][3][4][5][6][7][8][9][10]. The value of the moment required to maintain balance in relation to the tip-over axis [2,8,11,12] may constitute the measure of the risk of the crane tipping over.…”

Crane Stability Assessment Method in the Operating Cycle

“…Carrying large loads with the aid of truck mobile cranes may in certain conditions lead to a stability loss [2,[11][12][13][14][15][16][17][18][19]. The value of the moment required to maintain balance in relation to the tip-over axis [13,17,20,21] may constitute the measure of the risk of the crane tipping over.…”