Autonomous navigation of quadrotor is required by many application scenarios, such as exploration, search, and rescue. The trajectory planning algorithm is the core of autonomous navigation, which can undoubtedly greatly enhance the safety of flight. In this paper, a trajectory planning framework based on B‐spline and kinodynamic search is proposed. This framework can be used for a limited‐sensing quadrotor to plan safe and dynamically feasible trajectories in unknown environments, and the flight is safe and effective along with these trajectories. First, a B‐spline based nonuniform kinodynamic (BNUK) search algorithm is proposed to generate dynamically feasible trajectories efficiently. The characteristics of nonuniform search make the generated trajectories safe and reasonable time‐allocation. Then, a trajectory optimization method based on control point optimization is proposed. The trajectory generated by BNUK is further optimized by solving a quadratically constrained quadratic programming problem. The smoothness of the trajectory is improved, and the control cost is reduced. Extensive analysis and comparative simulation experiments verify the advancedness of the proposed framework. We also integrated it into a vision‐based quadrotor autonomous navigation system, and multiple outdoor flight experiments show the effectiveness of the proposed framework.

中文翻译：

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基于B样条和非均匀运动学搜索的实时四旋翼轨迹规划框架

在许多应用场景中，例如探索，搜索和救援，都需要四旋翼的自主导航。轨迹规划算法是自主导航的核心，无疑可以大大提高飞行的安全性。本文提出了一种基于B样条和运动学搜索的轨迹规划框架。此框架可用于有限感测四旋翼飞机，以在未知环境中规划安全和动态可行的轨迹，并且飞行与这些轨迹一起安全有效。首先，提出了一种基于B样条的非均匀运动学（BNUK）搜索算法，以有效地生成动态可行的轨迹。非均匀搜索的特征使生成的轨迹安全合理地分配时间。然后，提出了一种基于控制点优化的轨迹优化方法。通过解决二次约束二次规划问题，进一步优化了BNUK生成的轨迹。改善了轨迹的平滑度，并降低了控制成本。大量的分析和比较模拟实验验证了所提出框架的先进性。我们还将其集成到基于视觉的四旋翼自主导航系统中，并且多次户外飞行实验证明了所提出框架的有效性。大量的分析和比较模拟实验验证了所提出框架的先进性。我们还将其集成到基于视觉的四旋翼自主导航系统中，并且多次户外飞行实验证明了所提出框架的有效性。大量的分析和比较模拟实验验证了所提出框架的先进性。我们还将其集成到基于视觉的四旋翼自主导航系统中，并且多次户外飞行实验证明了所提出框架的有效性。