In order to improve the motion accuracy and dynamic performance of the aerial robotic arm, a 2-degree of freedom rope-driven aerial robotic arm is designed for the increasingly complex sampling working conditions. Firstly, a three-dimensional model of the robotic arm is established. Secondly, the dynamics of the aerial robotic arm with multi-body system is modeled by applying Spatial operator algebra. Further, the modal frequencies of different orders are obtained by modelling the flexible bodies of the specified components. Finally, a joint simulation is carried out using ADAMS and ANSYS under the same driving function to obtain a rigid-flexible coupled model of the robotic arm and to obtain the dynamic performance of the main components in terms of displacement, angular velocity and angular acceleration. The conclusion shows that the consideration of the flexible deformation of each joint is very necessary in the study of the system, and the rigid-flexible coupling modeling is closer to the actual, and the results are consistent. The obtained results also show that the robotic arm has a wide applicability, indicating the correctness of the design structure, and laying the theoretical foundation for the subsequent control system and structural optimization.