In recent years,modular self-reconfigurable robots have attracted much attention due to their complex and diverse configurations,varied motion modes and reconfigurable target configurations.By summarizing the literature on the key technologies of modular self-reconfigurable robots,the existing key technologies of modular self-reconfigurable robots were summarized comprehensively.Firstly,the structural characteristics and topological structure of the modular self-reconfigurable robot were introduced,and the advantages and disadvantages of the three topological structures as well as the development trend were analyzed.Secondly,the existing key technologies of self-reconfigurable robots were summarized,focusing on the physical principles and basic structures of three different connection structures of modular self-reconfigurable robots,the reconstruction algorithm of robot modules and the rapidity of the reconstruction process.The advantages and disadvantages as well as the development status of these technologies were analyzed and summarized.Finally,the development prospects of the space in-orbit and rescue and disaster relief tasks of the self-reconfiguration robot were prospected,and the future research priorities were proposed as follows:1) To explore the method of both strong stiffness and light weight of the connected structure to efficiently and quickly complete the robot reconfiguration process;2) To develop high fault tolerance and low energy consumption of reconstruction algorithm during operation;3) To combine the real-time data with the established dynamic model organically to manually adjust the robot and improve the operating efficiency of the robot.