Determination of Kingpin Axis from Wheel Points Using Dual Quaternion Analysis

Kingpin axis geometry is crucial to the design of a suspension system. Suspension construction is truly three-dimensional, and the screw axis theory allows for a more accurate kinematic analysis. This study aims to present a dual quaternion analysis (DQA) method for calculating the kingpin axis geometry. The corresponding parameters include the caster angle, SAI angle, toe angle, caster trail and scrub radius. An ADAMS/Car simulation model for the strut-SLA suspension is employed to assess the efficiency of the proposed method. Two distinctive marker sets and the marker coordinates are extracted from the kinematic model. In addition, the finite screw axis (FSA) method is employed for purposes of comparison with the DQA method. The results reveal that the marker distribution has a significant effect on calculating the position of the screw axis. In contrast to the FSA method, the DQA analysis is immune to any singularities because it enables the simultaneous matrix of rotation and translation. Thus, the proposed method is suitable for determining the kingpin axis and its related parameters in a K&C test.