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Tele-Autonomous control involving contactObject localization and its application in tele-autonomous systems are studied. Two object localization algorithms are presented together with the methods of extracting several important types of object features. The first algorithm is based on line-segment to line-segment matching. Line range sensors are used to extract line-segment features from an object. The extracted features are matched to corresponding model features to compute the location of the object. The inputs of the second algorithm are not limited only to the line features. Featured points (point to point matching) and featured unit direction vectors (vector to vector matching) can also be used as the inputs of the algorithm, and there is no upper limit on the number of the features inputed. The algorithm will allow the use of redundant features to find a better solution. The algorithm uses dual number quaternions to represent the position and orientation of an object and uses the least squares optimization method to find an optimal solution for the object's location. The advantage of using this representation is that the method solves for the location estimation by minimizing a single cost function associated with the sum of the orientation and position errors and thus has a better performance on the estimation, both in accuracy and speed, than that of other similar algorithms. The difficulties when the operator is controlling a remote robot to perform manipulation tasks are also discussed. The main problems facing the operator are time delays on the signal transmission and the uncertainties of the remote environment. How object localization techniques can be used together with other techniques such as predictor display and time desynchronization to help to overcome these difficulties are then discussed.
Document ID
19900019538
Acquisition Source
Legacy CDMS
Document Type
Thesis/Dissertation
Authors
Shao, Lejun
(Michigan Univ. Ann Arbor, MI, United States)
Volz, Richard A.
(Michigan Univ. Ann Arbor, MI, United States)
Conway, Lynn
(Michigan Univ. Ann Arbor, MI, United States)
Walker, Michael W.
(Michigan Univ. Ann Arbor, MI, United States)
Date Acquired
September 6, 2013
Publication Date
March 1, 1990
Subject Category
Mechanical Engineering
Report/Patent Number
NAS 1.26:187004
NASA-CR-187004
Report Number: NAS 1.26:187004
Report Number: NASA-CR-187004
Accession Number
90N28854
Funding Number(s)
CONTRACT_GRANT: NAG5-1024
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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