Abstract:This paper investigates the stability control of body-fixed hovering orbit over the near-Earth asteroid 433 Eros. Its gravitational field is approximated simulated by using the triaxial ellipsoidal model. Dynamical equations of the spacecraft near 433 Eros are derived. The time-varying sliding mode control with the same acceleration and variable intercept is adopted to design the hovering controller. Meanwhile, the sliding surface in this method is different from the conventional sliding mode control, where there is no reaching phase. Numerical simulations are then carried out with different initial conditions and hovering conditions to evaluate the effectiveness of the designed controller. The maximum values of spacecraft velocity and acceleration are analyzed by varying the switching time of sliding surface.