Distributed fixed‐time attitude coordination control for multiple rigid spacecraft

Abstract

Summary In this paper, the fixed‐time attitude coordination control for multiple rigid spacecraft under an undirected communication graph is investigated. By using the backstepping technique, the distributed fixed‐time observer, and the method of “adding a power integrator,” a distributed fixed‐time attitude coordination control law is designed for a group of spacecraft. The proposed control scheme is nonsingular and can guarantee a group of rigid spacecraft simultaneously tracking a common desired attitude within fixed time even when the time‐varying reference attitude is available only to a subset of the group members. Rigorous analysis is provided to show that the attitude consensus tracking errors can converge to the origin in finite time which is bounded by a fixed constant independent of initial conditions. Numerical simulations are carried out to demonstrate the effectiveness of the proposed control law.

Fixed‐time output‐feedback consensus tracking control for second‐order multiagent systems

“…Moreover, full-state measurements are required in other works. [22][23][24][25][26][27] Nevertheless, the main contribution of this work is the design of a distributed fixed-time consensus tracking scheme without using full-state measurements.…”

“…Remark In the existing literature, the design approaches for fixed‐time consensus control of second‐order multiagent systems usually include the terminal sliding mode control method, the technique of “adding a power integrator,” and the homogeneity theorem . One disadvantage of the design approach using the homogeneity theorem is that the settling time may not be explicitly calculated.…”

“…By the use of sliding mode control and/or bilimit homogeneity, fixed‐time consensus control for second‐order multiagent systems has been studied by several researchers . Using the backstepping technique, the distributed fixed‐time observer, and the method of “adding a power integrator,” a distributed fixed‐time attitude coordination control law is designed for a group of spacecraft . However, full‐state measurements are required in these works.…”

“…is designed for a group of spacecraft. 27 However, full-state measurements are required in these works. Recently, the problem of fixed-time output-feedback consensus control has been studied in the works of Tian et al 28 and Huang and Jia.…”

“…The fixed-time stability of the origin of the closed-loop system is proven by using the homogeneous Lyapunov function and the homogeneity property. The main contributions of this paper are stated as follows: (1) different from the other works, [22][23][24][25][27][28][29] the homogeneous Lyapunov function and homogeneity property are employed to analyze the fixed-time stability of the equilibrium of the closed-loop system; (2) in contrast to the existing fixed-time consensus control laws, [22][23][24][25][26][27] only partial state measurements are required in the proposed control law, which can reduce the cost related to on-board sensors; (3) as compared with the designed control schemes, 22,28 the implementation of the fixed-time consensus tracking control law presented in this paper does not have the algebraic loop problem.…”