Model-Based Efficient and Safe Spacecraft Operations Planner Focusing on Battery State Management

抄録

There is an increase in the popularity of small spacecraft because they are expected to introduce large opportunities in the space industry. However, there are two issues with increased use of small spacecraft: enhancement of cost-effectiveness and improvement in the mission failure rate. This study defines the battery state as the most important parameter in spacecraft operations because it directly relates to the health status of the spacecraft. We propose solving problems by introducing high-accuracy in situ state estimations for real-time operation mode selection and on-ground future state estimations of the battery in spacecraft operations planning by utilizing a suitable numerical model. The high-accuracy in situ state estimations allow us to minimize operational margins for battery protection, improve the efficiency of each spacecraft, and achieve safe spacecraft operations. The combination of a model-based system development approach and numerical optimization methods helps establish an efficient autonomous mission operations planner system to maximize mission duration. This enables us to reduce the human resource costs for spacecraft operations. This study addresses two topics: battery and spacecraft modeling, and establishing a mission operations planner system. The details of the system and battery modeling considering temperature dependence are explained using parameter identification results from the experiments. The design policy of the mission operations planner, which utilizes the battery status as the threshold of the operations and constraints, is explained via numerical optimization details. Numerical and experimental case studies are performed to evaluate the proposed method and show its effectiveness.