Author: CislunarSpace
Website: https://cislunarspace.cn
Northwestern Polytechnical University
Northwestern Polytechnical University (NPU, 西北工业大学) is located in Xi'an, Shaanxi Province. It is a national "Double First-Class" university under the Ministry of Industry and Information Technology, with distinctive strengths in aeronautics, astronautics, and marine engineering. The university traces its origins to three predecessor institutions — the National Northwest Engineering College, the East China Aviation Institute, and the Air Force Engineering Department of the Harbin Military Engineering Institute — and has been designated a national key university since 1960. NPU was among the first cohort of "Project 211" institutions (1995), entered "Project 985" (2001), and joined the "Double First-Class" initiative (2017, Category A).
NPU is organized around 23 schools covering aeronautics, astronautics, marine engineering, artificial intelligence, and related fields. It offers 73 undergraduate programs, 39 master's-level first-discipline authorization points, and 31 doctoral first-discipline authorization points. Three disciplines — Aeronautical and Astronautical Science and Technology, Materials Science and Engineering, and Mechanical Engineering — are on the national "Double First-Class" list. Thirteen disciplines rank in the top 1 % of ESI, with Engineering in the top 1‱.
NPU has a strong record in small satellite development and deep-space mission support. The university developed the world's first 12U CubeSat ("Aoxiang Star") and has launched small satellites for scientific and technology demonstration missions. NPU's research portfolio relevant to cislunar space spans orbital game theory, formation flying, and space debris inspection.
Dang Zhaohui
Orbital game theory in cislunar space
Game-theoretic maneuvering strategies for orbital inspection of non-cooperative spacecraft in cislunar space
Reference: Han H, Dang Z. Game-theoretic maneuvering strategies for orbital inspection of non-cooperative spacecraft in cislunar space[J]. Chinese Journal of Aeronautics, 2025, 39: 103574.
Abstract: The problem of maneuvering for a servicing spacecraft (inspector) to inspect a noncooperative spacecraft (evader) in cislunar space is investigated in this paper. The evader, which may be a malfunctioning or uncontrolled satellite, introduces uncertainties due to its potential maneuvering capabilities. To address this challenge, the scenario is modeled as a special orbital game, incorporating the unique complexities of the cislunar environment. A variable-duration, turn-based inspection and anti-inspection game model is designed. The model defines both players' rules, constraints, and victory conditions, providing a framework for non-cooperative inspection. Strategies for both players are developed and validated based on their dynamical properties. The inspector's strategy integrates two-body Lambert transfers with shooting methods, while the evader's strategy aims to maximize the inspector's fuel consumption. Simulation results show that the evader's optimal strategy involves deliberate fluctuations in its lunar periapsis altitude, with the inspector's required ΔV up to eight times greater than the evader's. The impact of game constraints is evaluated, and the effectiveness of deploying the inspector in low lunar orbit is compared with the inspector at the Earth-Moon Lagrange point L1. The strengths and weaknesses of both are shown. These findings provide valuable insights for future orbital servicing and orbital games.
Han Hongyu
Orbital game theory in cislunar space
Game-theoretic maneuvering strategies for orbital inspection of non-cooperative spacecraft in cislunar space
Reference: Han H, Dang Z. Game-theoretic maneuvering strategies for orbital inspection of non-cooperative spacecraft in cislunar space[J]. Chinese Journal of Aeronautics, 2025, 39: 103574.
Abstract: The problem of maneuvering for a servicing spacecraft (inspector) to inspect a noncooperative spacecraft (evader) in cislunar space is investigated in this paper. The evader, which may be a malfunctioning or uncontrolled satellite, introduces uncertainties due to its potential maneuvering capabilities. To address this challenge, the scenario is modeled as a special orbital game, incorporating the unique complexities of the cislunar environment. A variable-duration, turn-based inspection and anti-inspection game model is designed. The model defines both players' rules, constraints, and victory conditions, providing a framework for non-cooperative inspection. Strategies for both players are developed and validated based on their dynamical properties. The inspector's strategy integrates two-body Lambert transfers with shooting methods, while the evader's strategy aims to maximize the inspector's fuel consumption. Simulation results show that the evader's optimal strategy involves deliberate fluctuations in its lunar periapsis altitude, with the inspector's required ΔV up to eight times greater than the evader's. The impact of game constraints is evaluated, and the effectiveness of deploying the inspector in low lunar orbit is compared with the inspector at the Earth-Moon Lagrange point L1. The strengths and weaknesses of both are shown. These findings provide valuable insights for future orbital servicing and orbital games.