Optimal Design of Rocket Hold-down and Release Device Based on the Optimal Deceleration Curve

The mechanism-type hold-down and release mechanism is characterized by high bearing capacity, reliable release, high environmental adaptation, and flexible design. It has been widely used in recent years for rocket launches. To further enrich the design theory of this type of mechanism, this paper is based on the kinematic principle of a six-rod mechanism. The conformational innovation of the Watt-II chain is utilized to design a hold-down and release mechanism that meets the design requirements. Its model is established through theoretical derivation, and the sustained-release characteristics of the mechanism are analyzed using dynamic simulation to verify the correctness of the theoretical model. On this basis, the target sustained release curve is defined as the optimized benchmark; minimizing the deviation of the cumulative release curve from this target sustained release curve serves as our optimization objective. The coordinates of the hinge point of the mechanism are selected as design variables, leading to a single-objective optimization mathematical model being constructed and solved to obtain an optimized sustained release characteristic curve. After calculation, it is found that, compared with before optimization, the average improvement rate of compatibility between the optimized sustained release curve and the target sustained release curve is 8.79%.