Folding optimization design and deployment analysis for film drag balloon
The drag balloon is one of the primary devices for deorbiting of low Earth orbit spacecraft at the end of their life.Since the thin membrane sphere must be stored in a confined space for an extended period before use,achieving high-density and low-damage folding and smooth inflation and deployment is crucial for its operation.Considering the drag balloon is mostly composed of a certain number of bonded valves,an optimal valve configuration design method that considers shape stability and cost efficiency is firstly proposed.Furthermore,for the single petal structure,a sym-metrical parallel z-type folding scheme is proposed,and methods for quantifying the folded volume and damage are provided.Then,to increase the folding-deployment ratio and reduce crease damage,an optimized folding scheme for the drag balloon is presented,and simulation of a sphere of 6-meter diameter is conducted.Based on this scheme,the effects of valve configuration,inflation speed,and initial internal pressure and temperature on the smooth deploy-ment of the drag balloon are analyzed.The results show that the proposed folding scheme can achieve high-density and low-damage folding of the drag balloon.Additionally,by increasing the number of valves,slowing down the infla-tion speed,avoiding excessive vacuum,and reducing direct sunlight exposure,the attitude oscillation during the de-ployment process can be effectively mitigated,speeding up the attainment of a stable state.