Research on influence to guidance miss-distance by BTT control

In order to analyze the miss distance caused by the matching performance between pitch and roll control channels, a principle model about BTT guidance was built base on the BTT-90 command calculation logic and proportional navigation guidance law. The model included the simplified control system model and nonlinear model about guidance command calculation and aerodynamic translation. Taking the velocity pointing error and target maneuvering as the analysis conditions, the influence on the miss distance was analyzed and the STT control was compared also. The simulation results show that the total aerodynamic of system is determined by the slower autopilot within the pitch and roll control channels when BTT control used in the end guidance. It is the essential condition for the miss-distance converging to zero, that the guidance time is 10 times more than the aerodynamic time constant of the control system. To insure the high guidance accuracy, the response rate of the roll control channel should be faster than that of the pitch control channel. And only the response rate of the roll control channel is 5 times faster than that of pitch control channel, the miss distance of BTT will be close to that of STT.