Abstract Current practice for asteroid close proximity maneuvers requires extremely accurate characterization of the environmental dynamics and precise spacecraft positioning prior to the maneuver. This creates a delay of several months between the spacecraft's arrival and the ability to safely complete close proximity maneuvers. In this work we develop an adaptive integrated guidance, navigation, and control system that can complete these maneuvers in environments with unknown dynamics, with initial conditions spanning a large deployment region, and without a shape model of the asteroid. The system is implemented as a policy optimized using reinforcement meta-learning. The lander is equipped with an optical seeker that locks to either a terrain feature, reflected light from a targeting laser, or an active beacon, and the policy maps observations consisting of seeker angles and LIDAR range readings directly to engine thrust commands. The policy implements a recurrent network layer that allows the deployed policy to adapt real time to both environmental forces acting on the agent and internal disturbances such as actuator failure and center of mass variation. We validate the guidance system through simulated landing maneuvers in a six degrees-of-freedom simulator. The simulator randomizes the asteroid's characteristics such as solar radiation pressure, density, spin rate, and nutation angle, requiring the guidance and control system to adapt to the environment. We also demonstrate robustness to actuator failure, sensor bias, and changes in the lander's center of mass and inertia tensor. Finally, we suggest a concept of operations for asteroid close proximity maneuvers that is compatible with the guidance system.

中文翻译：

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通过强化元学习的终端自适应指导：在自主小行星近距离操作中的应用

摘要 当前的小行星近距离机动实践需要在机动之前对环境动力学和航天器的精确定位进行极其准确的表征。这在航天器到达和安全完成近距离机动之间造成了几个月的延迟。在这项工作中，我们开发了一种自适应集成制导、导航和控制系统，可以在动态未知的环境中完成这些机动，初始条件跨越大部署区域，并且没有小行星的形状模型。该系统被实现为使用强化元学习优化的策略。着陆器配备了一个光学导引头，可锁定地形特征、目标激光的反射光或主动信标，该策略将包括导引头角度和激光雷达范围读数的观测结果直接映射到发动机推力命令。该策略实现了一个循环网络层，允许部署的策略实时适应作用于代理的环境力和内部干扰，例如执行器故障和质心变化。我们通过在六自由度模拟器中模拟着陆操作来验证制导系统。模拟器随机化小行星的太阳辐射压力、密度、自转速度和章动角等特性，需要引导和控制系统适应环境。我们还展示了对执行器故障、传感器偏差以及着陆器质心和惯性张量变化的鲁棒性。最后，