Adaptive Sliding-Mode Guidance for Terminal Phase of Approaching Observation

An adaptive sliding-mode guidance is presented for the problem of terminal phase of approaching observation. Nominal trajectory designed previously was taken to get the relative state between the observation spacecraft and the target, which was regarded as the nominal data. Then state equations of relative motion were discretized and the Kalman Filter method was introduced to process the observation data. Sliding-mode Guidance laws in three channels were designed respectively in finite thrust to track the nominal data and adaptive method was adopted to eliminate system chattering. Finally, Simulations were given and their results showed the proposed guidance law can meet the requirements of approaching observation mission with a high precision. The study herein also can be used in the Missions such as Deep-space exploration and rendezvous and docking.