A method is derived from Kepler's laws of motion allowing the determination of slant range for orbiting targets
given monocular angles-only measurements. The method is shown to work without knowledge of three parameters:
universal gravitational constant, mass of the central body, and time scale. Monte Carlo trials with noisy data sets,
however, show that the method is much more sensitive to measurement noise than competing methods that require
knowledge of these parameters.
Pressure sense lines, as employed in the measurement of rocket engine test firings, can propagate the time-domain pressure signal out of hostile regions and allow instrumentation with pressure transducers. In such applications, it is necessary to correct the data to account for attenuation and resonance due to the sense line. One technique for doing so is the application of Fourier transform theory to obtain the transfer function of the sense line. Various techniques for obtaining the transfer function are explored, including the use of Gaussian noise, single frequency sweeps, and impulse signals as input functions. The transfer function thus obtained is mathematically fit, scaled, and validated against a related system.
Any system that will aid the military pilot in directing fire or sensors or aid in the stabilization of imagery that is captured by the aircraft's sensors would substantially increase the pilot's effectiveness. Several optical techniques are described in this presentation for determining the orientation and position of a pilot's helmet, which is actually one of the first requirements in accomplishing the tasks just listed. These techniques are all passive in that they require no input from the pilot except perhaps for an initial calibration, which would likely be valid for a particular pilot for any subsequent flight. The problem of determining the position and orientation of a pilot's helmet can be thought of as determining the position and orientation of a vector that starts at the center of the pilot's head and points forward. If we take this vector to be of a fixed (arbitrary) length, the problem reduces to the determination of five independent variables. Several techniques are investigated that range from the very simple, direct view and map approach to complicated routines involving color mixing, optical correlation, time of flight measurements, intensity gradients, and fiber optic gyroscopes. All of these approaches work. The true goal of this investigation is to define the problem physically and mathematically, and to analyze all of the approaches and ultimately determine the advantages and disadvantages of each before much laboratory equipment has been dedicated and other expensive equipment purchased.
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