Study On Dynamics And Design Theory Of Fuze Ball Rotor

The fuze ball rotor is one of typical primary explosive safety devices in the fuze ofspinning projectile. It not only can ensure primary explosive safety, but also is one ofarming delay devices. In order to look for the means to delay the arming time of fuze ballrotor, model building with dynamics of rigid bodies, numerical simulation with computerand testing by experimental research are used to researched the dynamics model anddesign theory of fuze ball rotor whose mass center doesn't coincide with its geometriccenter and has an offset from spin axis of the projectile.Following aspects are included:First, the dynamics model of fuze ball rotor is researched. The Euler dynamics theoryof rigid bodies is applied to analyze the dynamics of ball rotor whose mass center doesn'tcoincide with its geometric center and has an offset from spin axis of the projectile, thenonlinear ordinary differential equations of the motion of the fuze ball rotor is got.Second, spin eccentricity of fuze ball rotor is researched. The vector dimension chainwith random direction which including its spin eccentricity is analyzed in detail and itsspin eccentricity is calculated with Monte-Carlo simulating method. In the calculation thecoaxiality marked with correlation principle regarded as one of component links of thedimension chain is referred to. The simulation results is contrasted and analyzed with theresult that was got from extremum method and probability statistics method. Thesimulation results from Monte-Carlo simulating method show that the value of spineccentricity for the device in fuze obeys skew distribution that approximates to Rayleighdistribution and its direction angle is symmetrical about zero degree. But it obeys neitheruniform distribution nor normal distribution.Third, starting performance of fuze ball rotor is researched. The balanced equations ofapplied force of starting moment of fuze ball rotor were established. The initial conditionto solve the ball rotor movement differential equations when the mass center of fuze ballrotor doesn't coincide with its geometric center and has an offset from spin axis of theprojectile is calculated. The influence of design parameter and ballistic environment tostarting performance is discussed.Fourth, dynamics simulation for fuze ball rotor is researched. The programme, whichis used to solve the ball rotor movement ordinary differential equations when the masscenter of fuze ball rotor doesn't coincide with its geometric center and has an offset fromspin axis of the projectile, is programmed. The influence of design parameter and ballistic environment to the rotating motion and the means to delay the arming time of fuze ballrotor is discussed.Fifth, dynamic balanced angle of fuze ball rotor is researched. The balanced equationsof applied force at finishing point of rotating motion of fuze ball rotor were established.The finishing condition is discussed for solving differential equations of the rotatingmotion of fuze ball rotor whose mass center doesn't coincide with its geometric center andhas an offset from spin axis of the projectile. The dynamic balanced angle of eight kinds offuze ball rotor is got through solving this nonlinear equation. The influence of designparameter and ballistic environment to the dynamic balanced angle is discussed.Sixth, simulation experimentation of fuze ball rotor for dynamics performance isresearched. One kind of experimentation to get the trace of fuze ball rotor without touchingis designed through marking by laser. The trace of fuze ball rotor with different mechanicsparameters are got, and was contrastively analyzed to the simulation result which was getthrough the dynamics model. They are very similar which suggested that the model wasproved to be right and the model can provide theory guidance for the design fuze ball rotor.