The velocity center theorem of a spinning mobile object and its application to the vehicles

Application to the automobiles

Abstract

In the previous report ”The velocity center theorem of a spinning mobile object and its application to the vehicles”( DOI: https://doi.org/10.51094/jxiv.314  ) , described the application of the velocity center theorem to the mobility.  In this report, consider the case of applying the velocity center theorem to the front wheel steering automobiles.  When the automobile moves forward while changing its direction, the velocity center point CV is on the wheel axial intersection point, so CV is on the extension line of rear wheel axis.,　　When the traveling direction of the representative point CS and the direction of the automobile’ center line do not match, and the point CS goes straight, the center line of the automobile gradually approaches the traveling direction of point CS.  If the point CS goes curve line, the turning center CT of CS is on the straight line through CS and CV.  And when point CV and point CT do not match, point CV gradually approaches point CT, so the whole of the automobile approaches to the turning motion centered on point CT. Also, when  is defined as the turning radius of CS that is the distance from CS to CT, θ is the angle of automobile’s center line from the traveling direction of CS, L is the distance from rear wheel axis to point CS, and  is defined as , θ converges to . (If CS goes straight, )  The wheel axial intersection point (CV) is often referred to as the center of turning motion, but it is not necessarily that the turning center point CT is on the extension lines of wheels axis.  These show that the representative point CS is able to correct its posture in the proper direction while moving along the ideal trajectory.  This method is useful for autonomous driving and posture control etc.