Abstract：Lightweight design of rocket sled structure is very important to improve the level of rocket sled test. However, the dynamic characteristics and uncertainties of the rocket sled are complex. How to reduce the weight of the structure and ensure the reliability of the structure is the key. This paper proposes a novel reliability-based topology optimization method for rocket sled structure considering the dynamic characteristics and multi-source uncertainty based on the level set method. Firstly, this paper analyzes the characteristics of rocket sled structures and provides specific ways of rigid flexible coupling. Based on the joint simulation of ANSYS and ADAMS, the dynamic simulation of rocket sled structure under rigid flexible coupling condition is realized. The severe load cases between the slider and the track are extracted and used as the load input for the topology optimization of the rocket sled structure. Furthermore, the influence of uncertainties such as material properties and load amplitude is quantified based on the interval model. The reliability index is constructed to evaluate the structural performance. Then, a topology optimization model for the rocket sled structure is constructed based on the level set method, where the constraint condition is the reliability constraint of structural displacement. The example achieved a weight reduction of over 30% for the rocket sled structure under the condition of reliability not less than 90%. And all calculations can be completed in about 2 minutes. The numerical results show that considering the influence of uncertainty is important for topology optimization of rocket sled structures. Improving structural reliability can be achieved by using more materials or designing new force transmission paths. Although this article simplifies the rocket sled structure into a two-dimensional region for topology optimization, the simulation under rigid flexible coupling conditions, equivalent boundary conditions of the rocket sled structure, and methods for handling uncertainties involved are universal and also applicable to the design of three-dimensional rocket sled structures.
2025, Vol. 46 
