The letter presents a trailer-maneuverability analysis for the N-trailer kinematic structures comprising a tractor and an arbitrary number of single-axle trailers equipped with steerable or fixed wheels. For an elliptically-shaped set of tractor's input-velocities, we derive a mobility-ellipse generated in a velocity space of the (last) trailer. We show that the on-axle type of hitching present in the N-trailer leads to a singularity of a trailer-mobility (at least one degree of mobility is lost). Furthermore, we provide some relations between kinematic parameters of the N-trailer and its control inputs which enable shaping the trailer-mobility ellipse and decoupling it from a joint-configuration of the vehicle.

中文翻译：

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N 拖车结构中的拖车机动性

这封信对 N 拖车运动结构进行了拖车机动性分析，该结构包括一台牵引车和任意数量的配备可转向或固定轮的单轴拖车。对于一组椭圆形的拖拉机输入速度，我们推导出在（最后一个）拖车的速度空间中生成的移动性椭圆。我们表明，N 拖车中存在的轴上挂接类型导致拖车移动性的奇异性（至少失去了一个移动度）。此外，我们提供了 N 拖车的运动学参数与其控制输入之间的一些关系，这些关系能够塑造拖车移动椭圆并将其与车辆的关节配置分离。