A pointing-based method for spacecraft attitude maneuver path planning under time-varying pointing constraints

Abstract

The requirement to observe moving targets raises the time-varying pointing constraint for spacecraft attitude maneuver, which is seldom considered in existing attitude maneuver path planning methods. Therefore, a pointing-based method for attitude maneuver path planning under time-varying pointing constraints is proposed. Considering that pointing constraints are exerted on the perceptional sensor of spacecraft, an improved rapidly-exploration random tree method is designed to obtain the rotational pointing nodes while satisfying the pointing constraints. To this end, the key point is to define the time property of sampled nodes to determine their relations with time-varying constraints. Subsequently, the attitude quaternion nodes are generated according to pointing nodes. Finally, to find a continuous quaternion curve passing through quaternion nodes, component-wise and piecewise quaternion interpolation functions are adopted to calculate the angular velocity and control torque by the inverse dynamics method. The attitude motion spherical shell is designed by using the radial component to represent the timeline to visually display the satisfaction of time-varying constraints. Simulation results are used to validate the feasibility of the proposed method.