[3] [3] ZHOU N,XIA Y Q.Coordination control design for formation reconfiguration of multiple spacecraft［J］.IET Control Theory & Applications,2019,9(15):2222-2231.

[4] [4] ZHAO S Y,ZELAZO D.Bearing rigidity theory and its applications for control and estimation of network systems:life beyond distance rigidity［J］.IEEE Control Systems,2019, 39(2):66-83.

[7] [7] JIN J,RAMIREZ J P,WEE S G,et al.A switched-system approach to formation control and heading consensus for multi-robot systems［J］.Intelligent Service Robotics,2018, 11(2):207-24.

[8] [8] ZHAO S Y,ZELAZO D.Bearing rigidity and almost global bearing-only formation stabilization［J］.IEEE Transactions on Automatic Control,2015,61(5):1255-1268.

[10] [10] PARK M C,OH K K,AHN H S.Modified gradient control for acyclic minimally persistent formations to escape from collinear position［C］//The 51st IEEE Conference on Decision and Control，2012:1423-1427.

[11] [11] YU C,HENDRICKX J M,FIDAN B,et al.Three and higher dimensional autonomous formations:rigidity,persistence and structural persistence［J］.Automatica,2007,43(3):387-402.

[12] [12] HASSAN K K，JESSY W G.Nonlinear systems［M］.Upper Saddle River: Prentice Hall,2002.