Dynamics Simulation of Fuse Runaway Escapement Based on RMSTMM

The non-return-torque clock mechanism is usually used as a safing and arming mechanism for rotating projectiles, and its reliability is directly related to the safety of the fuze. The accidental release of the clock mechanism is a rare event, and the ballistic environment of the high-speed rotating projectile is complex and instantaneous, making it difficult to reconstruct the movement history of the clock mechanism when the fuze failure through multiple experiments. Therefore, dynamic simulation can only be conducted on the motion process of the fuze mechanism under different ballistic environments. This paper establishes dynamic models of a clock safety and arming device based on Lagrange method and Reduced Multibody Transfer Matrix Method. Based on the actual structure, the contact relationship of each component is obtained, and the dynamic response of the fuze under six degrees of freedom overload in the chamber is calculated. The motion history curves of each component during the launch process are obtained. The coefficient of determination (R2) between the central wheel’s rotational displacement profiles computed using the two algorithms reaches 0.994239, demonstrating exceptional agreement in angular kinematics. The methodology developed in this study enables precise computation of the motion of the clock mechanism across varied ballistic conditions, establishing a theoretical framework for cause analysis of accidental release of fuze.