Simulation and Evaluation of a Space Station Operational Plan Considering Launch Delay of Cargo Vehicles

Efficient operation is important to make full use of the capabilities of China’s space station. Determining the stochastic impacts of emergencies on the operational scenario of the space station is critical for successful implementation. However, few studies have assessed the uncertainties in the operational processes of the space station. To fill this gap, discrete event simulation (DES) is used to develop an evaluation method for the contingent operational plan of a space station. First, DES is used to develop a model framework of the space station operations, and the launch delay of cargo vehicles is introduced into the integrated simulation procedure. Second, the precision of the results and the computational efficiency are improved using the variance reduction technique. The corresponding effect on the number of simulation trials is confirmed using four constraints and three measurable metrics. Finally, the proposed method is applied to a two-year space station operational plan. The results show that maintaining a short interval between the launch date of the cargo vehicles and the start of the launch windows can decrease prolonged duration after a launch delay. A statistical analysis can be used to determine a safe interval between the dates of the events and vehicle launch.