The Design Of Gliding Trajectory And The Study Of Controllable Ballistic Characteristics For Projectile

Extended Range Technology is one of key development directions for projectiles and the gliding flight of projectile is an effective extended range technique at present.The ballistics theory and design method for Glide Range-Extended Projectile(GREP)were studied in this dissertation centering on several basic theoretical and technological problems met in the GREP research.According to the configuration characteristic of GREP,the aerodynamic calculation methods were selected to calculate the aerodynamic characteristics for control surface and empennage(wing)in different configurations along the projectile body.Not only does this aerodynamic calculation method have good accuracy and fast computational speed,but also has favorable generality.It can be applied to various projectiles with different shapes.The optimization model of aerodynamic configuration for GREP with canard configuration was established.An approach of aerodynamic shape optimization was proposed taking lift-to-drag ratio during flight and some aerodynamic and structural parameters as target function and constraints respectively.The six-degree spatial motion model was established according to the aerodynamic and movement characteristics for GREP.Based on Pontryagin minimum principle ((?)),the differential equations which can describe gliding flight were established and the existence of optimal solution during gliding flight for GREP was proved. The optimal variational rules of control parameter for projectile gliding flight were optimized using optimal control theory.A kind of engineering design method of gliding trajectory which uses maximal lift-to-drag ratio gliding flight to approach the optimal gliding trajectory was put forward.The main influencing factors of gliding trajectory and some ballistics characteristics different from conventional trajectory were analyzed by the numerical computation of trajectory for GREP.Through the linearization process of rigid body ballistic equations for GREP using disturbance theory,the projectile body transfer functions were derived.The static stability of undisturbed motion for GREP,the dynamic stability of lengthways free disturbed motion and the maneuverability of body owing to rudder impulse deflection were studied using transfer function analysis method.The results show that this kind of method is feasible to analyze dynamic characteristics of body for GREP during gliding flight.It can clearly shows that GREP during its gliding flight is whether or not have well anti-jamming ability and fast response control signal ability.A new PID Controller was designed by fractional calculus and that is fractional PI~λDμController.The effect of fractional PI~λD~μController parameters(K_P,K_D,K_I,λ,μ)on system was analyzed Systematically.And the parameter tuning method was proposed based on amplitude margin and phase margin.The design method of fractional Controller for angle stability loop and mass center control loop of GREP was studied.The fractional PI~λD~μController and integral PID Controller were designed respectively for some type GREP.The simulation results show that the fractional PI~λD~μController designed by this method has its own features compared with PID Controller.