This paper proposes a new approach to the carrot-chasing guidance law to provide an accurate trajectory-tracking function. The ahead-distance approach used in the conventional method highly depends on trajectory shapes and the complex geometric manipulation causes degraded performance. To overcome this disadvantage, the ahead-distance is replaced with the ahead time and the desired trajectory to the target point on the reference trajectory is generated using the Hermite spline interpolation. The desired aircraft’s states at the current time are estimated from the generated trajectory function and used to develop three kinds of the trajectory-tracking controllers. The effect of the ahead-time on achievable trajectory-tracking accuracy are thoroughly investigated through their applications to the rotorcraft guidance problems, which are defined by the prescribed trajectories for the transient turn and pirouette maneuvers. Finally, the guidance laws are applied to the complex mission profile consisting of the hover, acceleration, pop-up, helical turn, pop-down, and deceleration maneuvers to validate their usefulness. The best performance of guidance laws is investigated by the simulation around 5 second-ahead-time value. Hence, the proposed guidance laws provide accurate trajectory-tracking performances.

本文提出了一种新的胡萝卜追逐引导律方法，以提供准确的轨迹跟踪功能。传统方法中使用的超前方法高度依赖于轨迹形状，复杂的几何操作会导致性能下降。为了克服这个缺点，前进距离被提前时间替换，并且使用 Hermite 样条插值生成到参考轨迹上目标点的期望轨迹。根据生成的轨迹函数估计当前期望飞机的状态，并用于开发三种轨迹跟踪控制器。通过在旋翼机制导问题中的应用，彻底研究了提前时间对可实现的轨迹跟踪精度的影响，它们由瞬态转弯和旋转动作的规定轨迹定义。最后，将制导法则应用于由悬停、加速、弹起、螺旋转向、弹下和减速机动组成的复杂任务剖面，以验证它们的实用性。通过模拟大约 5 秒的提前时间值来研究制导律的最佳性能。因此，所提出的制导法则提供了准确的轨迹跟踪性能。通过模拟大约 5 秒的提前时间值来研究制导律的最佳性能。因此，所提出的制导法则提供了准确的轨迹跟踪性能。通过模拟大约 5 秒的提前时间值来研究制导律的最佳性能。因此，所提出的制导法则提供了准确的轨迹跟踪性能。