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Digital Control Techniques Concept Formulation Study.

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Final rept. 1 Jul 72-31 Jan 73,

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The objective of the Digital Control Techniques Concept Formulation Study was to develop and study new digital stability and control techniques for lock-on before launch, terminally guided, air-to-surface weapons. Digital filtering was studied for its application in signal smoothing and noise rejection. Kalman filtering was found to be impractical because of the inability to measure needed variables. Polynomial least-square filters were found to be excellent for extrapolating the guidance signal and differentiating angle measurements. Stability augmentation was achieved with body rate damping, derived from seeker angle motion, and time-varying gains to compensate for the velocity profile. A new digital approach for implementing a pulse ratio modulated actuator was developed. Three trajectory control algorithms were examined. The first, based on proportional navigation, used sample lead filters to improve accuracy. The second used an integral bias to eliminate trajectory sag. The third algorithm produced a vertical impact at the target. A programmable digital processor was designed to implement the autopilot equations. Both breadboard and production models were examined, the latter contains only 22 ICs and 6 IO micromodules and could be produced at very low cost in moderate quantities greater than 5,000. The processor has sufficient program and data memory to hold all three algorithms plus perform additional tasks as time and space permits. Author

Subject Categories:

  • Air- and Space-Launched Guided Missiles
  • Fire Control and Bombing Systems

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