2011 年 4 巻 2 号 p. 79-94
Directional response and directional stability of vehicle combinations are the main research topics in vehicle safety. This paper uses simplified mathematical models to analyze the steering sensitivity in lane-change maneuvers of multi-articulated vehicles with multiple axles. It also calculates the frequency response, pole, and zero in the transfer functions of each variable for two types of tractor and double-trailer combinations having multiple axles. The following conclusions are drawn. (1) Steering sensitivity of multi-articulated vehicles with multiple axles in lane-change maneuvers is composed of steering sensitivity in steady-state turns and the parameters of lane-change maneuvers. (2) The effect of the number of trailer axles on the damping ratio of zero is larger than that of the other parameters for multiple axles. (3) A large steering angle is necessary to change running lanes for multi-articulated vehicles with multiple axles that have low steering sensitivity in lane-change maneuvers; therefore, the rise time is short. Moreover, if the vehicle combination has a low damping ratio of oscillatory modes, the settling time is long, and the overshoot and maximum deviation are large.