A detailed analytical study of a wheeled double-articulated skidder is performed. Also experimental verification of the stability analysis is made using a scale model of the vehicle.
The double articulation joint allows both halves to rotate vertically as well as hinge horizontally. Equations locating the centers of gravity of each section of the vehicle are developed for the three basic modes of stability.
The three basic modes of static stability are front section tipping, rear section tipping and the entire vehicle tipping as a unit. The problem is complicated by including the cable winch load on the rear section of the skidder. This load varies in magnitude and direction.
The results are presented as stability curves in terms of hill slope, steering angle, vehicle orientation angle, articulation angle and cable force.
The analytical model and experimental model were in agreement. The skidder static stability was found to be very sensitive to its orientation angle on the hill and its steering angle.
This study provides a good basis for the dynamic study of the double-articulated logging tractor by showing the sensitive parameters which will affect stability.