No abstract

Modern warfare is a joint operation supported by space-based information, and space-based information is a “benefit multiplier” for joint combat effectiveness. In order to study the impact of space-based information support on joint operations, this paper improves the classical Lanchester equation [1] by introducing the space-based information support capability index, coordination index, decision-making index, etc. The Lanchester combat model was simulated and a scenario simulation was carried out. The simulation results show that the model can effectively describe the important support of space-based information for joint operations, and provides a theoretical reference for studying the winning mechanism of joint operations.

This paper attempts to solve the space pursuit and escape problems of a spacecraft with a fixed stay period. The artificial immune algorithm is used to solve the Nash equilibrium solution in the process of both parties’ pursuit and escape, which reduces the complexity of the bilateral optimal planning problem. According to the game process of the pursuit-and-escape, a mathematical model is established. Under the condition that both spacecraft are subjected to continuous thrust, the relative distance relationship between the two ends is defined as the objective function. To shorten the algorithm optimization time to ensure the calculation accuracy, the thrust pointing angle of the spacecraft is designed by integer coding, and the antigen-antibody affinity function is established accordingly. In this paper, the immune operator is designed and defined, which improves the searchability and convergence speed of the algorithm in three-dimensional space. The simulation example gives the optimal control strategy and the corresponding chasing trajectories of both parties, which effectively solves the problem of spacecraft chasing and escaping under a fixed time.

Wheel profile form directly affects the dynamic behaviour of rail vehicles. Moreover, it is an important factor to ensure the safe running of a high–speed vehicle. As off–line measurements do not provide high–efficiency and high–accuracy wheel profile measurements, we focused on on–machine measurement and evaluation for obtaining the wheel profiles of a rail vehicle in this study. By combining the wheel machining with the wheel measurement, the measurement and evaluation of radial and axial wheel profiles on the underfloor wheelset lathe were proposed. The measurement of radial wheel profile based on two laser sensors was introduced, and the corresponding error models of on–machine measurement were established. The error models were used to separate the measurement errors from the measurement data. This can improve the accuracy of measuring the radial wheel profile effectively. For measuring the axial wheel profile, an adaptive correction method of profile error was proposed to suppress the measurement error, which was the basis for obtaining an accurate equivalent conicity. By measuring radial and axial wheel profiles, polygonisation evaluation and equivalent conicity were obtained to evaluate the radial and axial dynamic behaviours of a wheelset, respectively. Finally, the measurements were applied to an underfloor wheelset lathe to verify the effectiveness of measuring wheel profiles. In this study, we not only improved working efficiency for the machine tools, but also provided a high–accuracy measurement method for the wheel profiles of rail vehicle.