Consideration to Mechanism and Improvement of Steering Motion due to Banking the Motorcycle 2018-32-0049
In order for a motorcycle to turn, it is necessary to steer and bank its body. It seems that the relationship between the steering and the banking is related to the maneuverability of the motorcycle. For example, a rider expresses a phenomenon that the steering by the banking is excessive than his expectation as “instability”. Therefore, in order to further improve the maneuverability of the motorcycle, I considered the mechanism and improvement of steering motion due to the banking
This paper starts with examining the relationship between time history response and eigenvalues of Sharp model. As a result, this phenomenon seems to be the capsize mode. To examine the capsize mode, I examined the relationship between the capsize and the equations of motion of Sharp model. As a result, I point out that the capsize mode is almost represented by the first order differential equation for the roll angular velocity and steady state terms in the equation of motion of its steering system. By considering this differential equation, I obtained the causal relationship that banking is the cause of the capsize mode and steering is its result. This causal relationship is consistent with the causal relation of "steering motion due to the banking" which is the subject of this thesis. Therefore, I judged that this phenomenon is the capsize. Therefore, as one of evaluation indexes of this phenomenon, a ratio of the steering angular velocity and the roll angle in the capsize mode is assumed. The influence of each design parameters on this index were calculated numerically. As a result, the most sensitive design variables were camber stiffness of the front and rear wheel.
Therefore, it seems that it is possible to design characteristics of this phenomenon by the camber stiffness of front and rear wheels.
SAE/JSAE Small Engine Technology Conference