Abstract: In order to guarantee higher stability precision, torque motors are generally employed to drive the integrated gimbal frames of the photoelectric stabilized platform directly. This leads to a lower load/self-weight ratio and makes it difficult to meet the requirement of light-weighted carriers like the unmanned aerial vehicle (UAV) in the future. A design scheme of inertially stabilized platform based on differential cable-driven mechanism is proposed based on the overview about the basic style of cable drive. Firstly, the topological structure, operating principle and structural features are analyzed. The kinematics is further studied to describe the quantitative relationship of the velocity inputs and outputs based on oriented graph method. And the results on the dynamic transfer characteristics between system inputs and load ends indicate that the essence of the differential mechanism is to enlarge and redistribute the input torques after synthesis, which has a major impact on increasing its load capacity. Results of theoretical analysis show that the platform designed and studied here can realize the motion of 2-DOF with power transmission and control, and validate the proposed scheme. The new configuration application is significant in reducing the weight of the drive system and enhancing the output torque. This may provide a reference for the further stabilized platform design.

Key words: differential cable-driven, kinematics, oriented graph method, power transmission, stabilized platform