A perfect duality exists between the problem of space-based orbit determination from line-of-sight measurements and the problem of designing an interplanetary autonomous navigation system. Mathematically, these two problems are equivalent. Any method solving the first problem can be used to solve the second one and, vice versa. While the first problem estimates the observed unknown object orbit using the known observer orbit, the second problem does exactly the opposite (e.g. the spacecraft observes a known visible planet). However, in an interplanetary navigation problem, in addition to the measurement noise, the following "perturbations" must be considered: 1) light-time effect due to the finite speed of light and large distances between the observer and planets, and 2) light aberration including special relativistic effect. These two effects require corrections of the initial orbit estimation problems. Because of the duality problem of space-based orbit determination, several new techniques of angles-only Initial Orbit Determination (IOD) are here developed which are capable of using multiple observations and provide higher orbit estimation accuracy and also they are not suffering from some of the limitations associated with the classical and some newly developed methods of initial orbit determination. Using multiple observations make these techniques suitable for the coplanar orbit determination problems which are the case for the spacecraft navigation using visible planets as the solar system planets are all almost coplanar. Four new IOD techniques were developed and Laplace method was modified. For the autonomous navigation purpose, Extended Kalman Filter (EKF) is employed. The output of the IOD algorithm is then used as the initial condition to extended Kalman filter. The two "perturbations" caused by light-time effect and stellar aberration including special relativistic effect also need to be taken into consideration and corrections should be implemented into the extended Kalman filter scheme for the autonomous spacecraft navigation problem.

The Hubble Space Telescope (HST) was originally proposed and funded in the 1970's with a launch planned for the early 1980's. However, the launch finally occurred on April 24, 1990, largely due to the Challenger accident. Once launched in 1990, one of HST's earliest projects was the Key Project. One of the main purposes of the Key Project was to calibrate the distances to nearby galaxies and determine a definitive value of the Hubble constant H0. All secondary distance determination methods were based on the period-luminosity relation of Cepheid variable stars. This thesis examines the Cepheid data from the Key Project by first redetermining the periods of Cepheids in selected galaxies and then applying a time correction to the data. This time correction is to compensate for the effects of the recessional motion of each galaxies, as caused by the finite speed of light. The recovery stage of the project was mostly successful, but revealed concerns with the original data set. This result led to less compelling results for the time-correction stage due to the larger than anticipated errors. A further examination was performed on part of the sample by using a more accurate form of the time input as found in the HST image headers. Overall we conclude that the short observation baseline of the Cepheids, with medium to long periods, is a major deficiency of the Cepheid data from the Key Project with regard to testing for the effects of recessional motion. Future studies on the effects of the time correction need to be done using data with longer time coverage that spans at least 4 pulsational cycles, perferably more than 30 cycles.

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The main aim of this master’s thesis is to provide online path correction of 6 – axis robot leaded by an external distance measuring sensor interface. First part is describing the actual state and required options of some robot manufacturers. Next part justifies selection and is describing the real robotic cell. Third part is focused on programming of path correction of Kuka KR16 based on generated signal and also based on signal from distance sensor interface. There is also described the communication between PLC and robot and how to display data from robot to HMI. Last part is focused on data analysis and is describing some problems discovered by application of path correction.