Research On Control For Rendezvous With Noncooperative Target In Orbit

There is a demand for the ability to autonomously inspect or rendezvous with noncooperative target due to the continuous increase of orbit activity. This technique may be used for servicing a malfunctioning satellite, re-fueling a powerless satellite, or collecting and removing space debris. This dissertation deeply studies the control methods for rendevous with noncooperative target in spece. The main contents of this dissertation are as follows:Fuel optimization for rendezvous between formation flying spacecraft with one or two impulses is studied. Optimal rendezvous time is calculated by genetic algorithm. Resolution expression of rendezvous with one impulse is founded by processing results of calculation with multivariate linear regression method. A controller for terminal approach is derived from relative motion equation founded in line of sight frame. The method of relative attitude control is designed. Angles-only relative navigation model considering J2 perturbation is presented for tracking and rendezvous with noncooperative target in highly elliptical orbit. For there are inherent problems in the ability of angles-only relative navigation system to determine the range to the Target, impulsive out-of-plane maneuvers of the Chaser are used to improve the navigation accuracy. The simulation results and theoretical analysis show that angles-only relative navigation with chaser vehicle maneuvers to improve observability is effective.To rescue the control-deficient target spacecraft, the chaser spacecraft are demanded to track the capture point at first. Fuel optimal control for capture of a free tumbling target considering collision avoidance is studied. The proportional-integral-derivative (PID) control method is used, and is improved to avoid collision between two spacecraft and to reduce fuel consume. The relative attitude controller are designed to meet the demand of relative attitude during Chaser tracking Target by the approved PID controller. According to the simulation results, the improved PID control method and the relative attitude control method are effective.The micro-satellite with limited capacity is demanded to capture noncooperative target. An initial control method and an end control method are designed to allow the micro-satellite to meet the demand. The initial control method based on C-W equations could save the fuel of micro-satellite and make a good initial condition for end control. The end control is derived from the relative motion equation in line of sight frame. The sufficient condition for success end approach is given. In order to improve the probability to capture target, the formation flying of micro-satellites is designed, and the control methods to initialize and keep the formation are derived. The simulation results show that the control methods designed are effective.