Reliability-Constrained Uncertain Spacecraft Sliding Mode Attitude Tracking Control With Interval Parameters

This study proposes a time-varying reliability-constrained uncertain sliding mode control to improve spacecraft attitude tracking under incomplete information, with uncertainties modeled as interval parameters. The need for sliding mode control in spacecraft attitude tracking is introduced, and a nominal controller with stability proof is developed. To overcome the challenge of large sample requirements in aerospace applications, an interval uncertainty analysis method is incorporated into the design of attitude prediction and tracking systems. An interval cooperative iterative prediction method, inspired by orthogonal polynomials, is introduced to estimate attitude angles accurately. The nominal controller is then converted into an interval-based sliding mode controller with trajectory bounds. To assess the dynamic safety of spacecraft, interval-based time-varying reliability is applied, accounting for constant or varying critical values of control system safety. An optimization problem based on the proposed method is solved using a multiobjective algorithm. A numerical example demonstrates the effectiveness of the approach, compared to Monte Carlo simulations.