Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also ...Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also need to modulate the lateral force or trajectory (perpendicular to the vertical plane of fire direction). Therefore, the structure of control cabin of two-dimensional trajectory correction projectile (TDTCP) is more complicated than that of one-dimensional trajectory correction projectile (ODTCP). To simplify the structure of control cabin of TDTCP and reduce the cost, a scheme of adding a damping disk to the control cabin of ODTCP has been developed recently. The damping disk is unfolded at the right moment during its flight to change the ballistic drift of spin stabilized projectile. For this technical scheme of TDTCP, a fast and accurate impact point prediction method based on extended Kalman filter is presented. An approximate formula for predicting the ballistic drift and trajectory correction quantity is deduced. And the lateral correction capability for different fire angles and its influencing factors are analyzed. All the work is valuable for further research.展开更多
This paper intends to provide theoretical basis for matching design of hydraulic load simulator (HLS) with aerocraft actuator in hardware-in-loop test, which is expected to help actuator designers overcome the obsta...This paper intends to provide theoretical basis for matching design of hydraulic load simulator (HLS) with aerocraft actuator in hardware-in-loop test, which is expected to help actuator designers overcome the obstacles in putting forward appropriate requirements of HLS. Traditional research overemphasizes the optimization of parameters and methods for HLS controllers. It lacks deliberation because experimental results and project experiences indicate different ultimate performance of a specific HLS. When the actuator paired with this HLS is replaced, the dynamic response and tracing precision of this HLS also change, and sometimes the whole system goes so far as to lose control. Based on the influence analysis of the preceding phenomena, a theory about matching design of aerocraft actuator with HLS is presented, together with two paired new concepts of "Standard Actuator" and "Standard HLS". Further research leads to seven important conclusions of matching design, which suggest that appropriate stiffness and output torque of HLS should be carefully designed and chosen for an actuator. Simulation results strongly support that the proposed principle of matching design can be anticipated to be one of the design criteria for HLS, and successfully used to explain experimental phenomena and project experiences.展开更多
The wind effects on steady-state scan characteristics and hit probability of terminal-sensitive projectile were discussed in this paper. Considering wind as the constitutions of the average wind and the impulsive wind...The wind effects on steady-state scan characteristics and hit probability of terminal-sensitive projectile were discussed in this paper. Considering wind as the constitutions of the average wind and the impulsive wind, a simplified wind field model was established for the ballistic calculation of the steady-state scan phase; under the windy condition, the effects of the range wind and the beam wind on the steady-state scan characteristics of the terminal-sensitive projectile were analyzed in detail and its hit probabilities for a certain armored target were calculated. The calculated results show that, when the wind speed exceeds a certain value, the hit probabilities of terminal-sensitive projectile drop rapidly; the wind effects must be considered in the application of the terminal-sensitive projectiles. This paper provides some theoretical references for the fire wind speed correction and the global structure optimization of the terminal-sensitive projectile.展开更多
文摘Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also need to modulate the lateral force or trajectory (perpendicular to the vertical plane of fire direction). Therefore, the structure of control cabin of two-dimensional trajectory correction projectile (TDTCP) is more complicated than that of one-dimensional trajectory correction projectile (ODTCP). To simplify the structure of control cabin of TDTCP and reduce the cost, a scheme of adding a damping disk to the control cabin of ODTCP has been developed recently. The damping disk is unfolded at the right moment during its flight to change the ballistic drift of spin stabilized projectile. For this technical scheme of TDTCP, a fast and accurate impact point prediction method based on extended Kalman filter is presented. An approximate formula for predicting the ballistic drift and trajectory correction quantity is deduced. And the lateral correction capability for different fire angles and its influencing factors are analyzed. All the work is valuable for further research.
基金the Aviation Science Foundation (No. 20110951009) of ChinaNational Nature Science Foundation for Distinguished Young Scholars ( No. 50825502 ) of China for the financial support
文摘This paper intends to provide theoretical basis for matching design of hydraulic load simulator (HLS) with aerocraft actuator in hardware-in-loop test, which is expected to help actuator designers overcome the obstacles in putting forward appropriate requirements of HLS. Traditional research overemphasizes the optimization of parameters and methods for HLS controllers. It lacks deliberation because experimental results and project experiences indicate different ultimate performance of a specific HLS. When the actuator paired with this HLS is replaced, the dynamic response and tracing precision of this HLS also change, and sometimes the whole system goes so far as to lose control. Based on the influence analysis of the preceding phenomena, a theory about matching design of aerocraft actuator with HLS is presented, together with two paired new concepts of "Standard Actuator" and "Standard HLS". Further research leads to seven important conclusions of matching design, which suggest that appropriate stiffness and output torque of HLS should be carefully designed and chosen for an actuator. Simulation results strongly support that the proposed principle of matching design can be anticipated to be one of the design criteria for HLS, and successfully used to explain experimental phenomena and project experiences.
基金Sponsored by Doctoral Foundation of Ministry of Education of China (20093219120006)
文摘The wind effects on steady-state scan characteristics and hit probability of terminal-sensitive projectile were discussed in this paper. Considering wind as the constitutions of the average wind and the impulsive wind, a simplified wind field model was established for the ballistic calculation of the steady-state scan phase; under the windy condition, the effects of the range wind and the beam wind on the steady-state scan characteristics of the terminal-sensitive projectile were analyzed in detail and its hit probabilities for a certain armored target were calculated. The calculated results show that, when the wind speed exceeds a certain value, the hit probabilities of terminal-sensitive projectile drop rapidly; the wind effects must be considered in the application of the terminal-sensitive projectiles. This paper provides some theoretical references for the fire wind speed correction and the global structure optimization of the terminal-sensitive projectile.