In conventional bilateral teleoperation, transmission delay over the Internet can potentially cause instability. The wave variable algorithm guarantees stability under varying transmission delay at the cost of poor transient performance. Adding a predictor on the master side can reduce this undesirable side-effect, but that would require a slave model. An inaccurate slave model used in the predictor as well as variations in transmission delay, both of which are likely under realistic situations, can result in steady state errors. A direct drift control algorithm is used to drive this error to zero regardless of the source of error. A semi-adaptive predictor that can distinguish between free space and rigid contact environment is used to provide more accurate force feedback on the master side. A full adaptive predictor is also used that estimates the slave environment parameters using recursive least squares with a forgetting factor. This research presents the experimental results and evaluations of the wave variable based methods under a realistic operation environment using a real master and slave. The effectiveness of this algorithm is fully evaluated using human subjects with no previous experience in haptics. Three algorithms are tested using PHANTOM brand haptic devices as master and slave: conventional bilateral teleoperation with no transmission delay as control, wave variable teleoperation with approximately 200 ms transmission delay one way, and wave variables with adaptive predictor and direct drift control with approximately 200 ms transmission delay one way. For each algorithm the human subjects are asked to perform three simple tasks: use the master to force the slave to track a reference trajectory in free space with the least amount of error, identify a contour surface on the slave side as accurately as possible using only haptic information from the master, and navigate a simple maze on the slave side in the least amount of time using haptic information from the master.

Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 128-134). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 128-134). Also available on the Internet.

Thesis (M.S.)--University of North Carolina at Wilmington, 2003. / Includes bibliographical references (leaf : [40]).

Thesis (M.S.)--University of North Carolina at Wilmington, 2005. / Includes bibliographical references (leaves: 60-61)

Thesis (Ph. D.)--University of California, San Diego, 1997. / Vita. Includes bibliographical references.

Thesis (Ph.D.)--University of North Carolina at Charlotte, 2005. / Includes bibliographical references (leaves 71-79).

No description available.

Two principal issues were.investigated in this experiment: (1) to determine if the performance of an operator controlling a simulated space vehicle was affected by variable transmission delays; and (2) to determine if an approximate predictor cue enhanced the operator's ability to control the vehicle. The study employed two independent variables, delay variability and prediction. There were four levels, or ranges, of delay variability; 2.50 ± 0.00, 2.50 ± 0.25, 2.50 ± 0.50, and 2.50 ± 1.00 s, and two levels of prediction, with and without prediction. The amount of fuel used to complete the task, the time to complete the task, error score (weighted deviations from the desired flight path), and a Cooper-Harper subjective rating were the dependent measures used to gauge the performance of the operator. Each of the eight treatment combinations contained three trials for the 12 operators to perform. The results of this experiment indicate that the greater the delay variability, the greater is the amount of fuel used for each task and the greater is the perceived difficulty. Prediction did not significantly enhance the operator's ability to control the vehicle. This result is probably due to one of two reasons: (1) the task itself was too easy; thus, the predictor did not assist the operators in completing the task, or (2) since the predictor was not completely accurate, the operators may have lacked confidence in its ability to improve their performance. Consequently, this result suggests that a predictor cue may not be useful for this type of situation. Recommendations are suggested for further research efforts associated with predictors used in conjunction with variable delay conditions. / M.S.

Thesis (M.S.) -- Mississippi State University. Department of Electrical and Computer Engineering. / Title from title screen. Includes bibliographical references.