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1 – 10 of 19Ibrar Jan, Umer Khan and Naeem Iqbal
Vision‐based inverted robot control exhibits a complex and a multi‐parameter estimation task. Compromises over speed and accuracy must be made to reduce the cost of the system, if…
Abstract
Purpose
Vision‐based inverted robot control exhibits a complex and a multi‐parameter estimation task. Compromises over speed and accuracy must be made to reduce the cost of the system, if high profile techniques are not utilized. The purpose of this paper is to present such a technique where many parameter estimation problems admit partitioning process. The process eliminates the complexity by dividing such a high dimension task into several reduced dimension problems. The partition procedure is defined by human understanding of the task. Here a mechanical setup is designed that handles the pose parameters estimations as a set of sub‐problems. The estimated pose parameters are applied to an inverted robot approaching a target on the floor.
Design/methodology/approach
A novel technique that helps the inverted robot to approach its target is detailed here. The new methodology is based upon the modified versions of existing and proven techniques of pure translations and rotations estimations. Providing valid conditions, the parameters of the two vectors of the camera's pose are isolated. In the first pass, the roll angle is adjusted. A subsequent pass uses modified 2‐point algorithm to estimate partial translational vector. Introducing 4‐point algorithm; an extension of pure rotational vector estimation technique, to estimate partial rotational vector. Lastly, visual depth is estimated to complete the task. For simplicity, the robot dynamics are not detailed here. It is assumed that the robot can possibly achieve any position if the desired pose parameters are known.
Findings
It is found that the isolated vectors estimation process reduces the complexity of the system and so reduces the computational cost and processing time. The proposed technique is applied to a prototype inverted Cartesian robot having 3D rotary wrist. Through analysis, it is observed that the estimated parameters are very close to the actual pose parameters.
Practical implications
The proposed technique can aid CNC vertical milling machines to countercheck the exact position and orientation of the tool w.r.t. the job. Similar systems in practice are DECKEL MAHO, DMU 60/80/100, 5‐axis package and DMC 35 V series.
Originality/value
The dynamic nature of the method proposed in the paper makes it more efficacious for mechanical/robotic systems with vertically downward tool under gravity effect.
Details
Keywords
Muhammad Umer Khan, Ibrar Jan and Naeem Iqbal
The purpose of this paper is to present the methodology to the robust stability analysis of a vision‐based control loop in an uncalibrated environment. The type of uncertainties…
Abstract
Purpose
The purpose of this paper is to present the methodology to the robust stability analysis of a vision‐based control loop in an uncalibrated environment. The type of uncertainties considered is the parametric uncertainties. The approach adopted in this paper utilizes quadratic Lyapunov function to determine the composite Jacobian matrix and ensures the robust stability using linear matrix inequality (LMI) optimization. The effectiveness of the proposed approach can be witnessed by applying it to two‐link robotic manipulator with the camera mounted on the end‐effector.
Design/methodology/approach
The objective of this research is the analysis of uncertain nonlinear system by representing it in differential‐algebraic form. By invoking the suitable system representation and Lyapunov analysis, the stability conditions are described in terms of linear matrix inequalities.
Findings
The proposed method is proved robust in the presence of parametric uncertainties.
Originality/value
Through a differential‐algebraic equation, LMI conditions are devised that ensure the stability of the uncertain system while providing an estimate of the domain of attraction based upon quadratic Lyapunov function.
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Keywords
Umer Khan, Ibrar Jan, Naeem Iqbal and Jian Dai
The purpose of this paper is to present the control of six degrees of freedom (PUMA560) robotic arm using visual servoing, based upon linear matrix inequality (LMI). The aim lies…
Abstract
Purpose
The purpose of this paper is to present the control of six degrees of freedom (PUMA560) robotic arm using visual servoing, based upon linear matrix inequality (LMI). The aim lies in developing such a method that neither involves camera calibration parameters nor inverse kinematics. The approach adopted in this paper includes transpose Jacobian control; thus, inverse of the Jacobian matrix is no longer required. By invoking the Lyapunov's direct method, closed‐loop stability of the system is ensured. Simulation results are shown for three different cases, which exhibit the system stability and convergence even in the presence of large errors.
Design/methodology/approach
The paper presents LMI‐based visual servo control of PUMA560 robotic arm.
Findings
The proposed method is implementable in the dynamic environment due to its independence to camera and object model.
Research limitations/implications
Visibility constraint is not included during servoing – this may cause features to leave the camera field of view (fov).
Originality/value
LMI optimization is employed for visual servo control in an uncalibrated environment. Lyapunov's direct method is utilized which ensures system stability and convergence.
Details
Keywords
Atefeh Hemmati, Mani Zarei and Amir Masoud Rahmani
Big data challenges and opportunities on the Internet of Vehicles (IoV) have emerged as a transformative paradigm to change intelligent transportation systems. With the growth of…
Abstract
Purpose
Big data challenges and opportunities on the Internet of Vehicles (IoV) have emerged as a transformative paradigm to change intelligent transportation systems. With the growth of data-driven applications and the advances in data analysis techniques, the potential for data-adaptive innovation in IoV applications becomes an outstanding development in future IoV. Therefore, this paper aims to focus on big data in IoV and to provide an analysis of the current state of research.
Design/methodology/approach
This review paper uses a systematic literature review methodology. It conducts a thorough search of academic databases to identify relevant scientific articles. By reviewing and analyzing the primary articles found in the big data in the IoV domain, 45 research articles from 2019 to 2023 were selected for detailed analysis.
Findings
This paper discovers the main applications, use cases and primary contexts considered for big data in IoV. Next, it documents challenges, opportunities, future research directions and open issues.
Research limitations/implications
This paper is based on academic articles published from 2019 to 2023. Therefore, scientific outputs published before 2019 are omitted.
Originality/value
This paper provides a thorough analysis of big data in IoV and considers distinct research questions corresponding to big data challenges and opportunities in IoV. It also provides valuable insights for researchers and practitioners in evolving this field by examining the existing fields and future directions for big data in the IoV ecosystem.
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THOSE who were present at the induction of the President of the Library Association on January 26th must have left that pleasant, but very limited, assembly with two thoughts ;…
Abstract
THOSE who were present at the induction of the President of the Library Association on January 26th must have left that pleasant, but very limited, assembly with two thoughts ; that the speeches were adequate and deserved a much wider audience than the relatively small Council Chamber at Chaucer House can accommodate, and that our affairs are in good hands for 1949. Mr. McColvin made the speech of thanks to Mr. Nowell, as a man straightforward, sane, loyal, simple, broadminded and fundamentally sound. We echo these and could add other praises but, fortunately, Mr. Nowell has many years of active service ahead, and we hope for many opportunities yet to acknowledge it. Sir Ronald Adams showed that modesty and charm which we were assured from his record he possesses. Our readers have found these speeches in the L.A. Record for February, and our only purpose in alluding to them is to say our own word of thanks for past service and our good wishes to both outgoing and incoming Presidents. And again to repeat our view that the Association loses a great ceremonial opportunity by holding the inauguration in a small room in London in the winter, rather than at the great annual assembly of the Conference as was at one time the practice. It was the central occasion of the year.
MID‐OCTOBER sees the activities of the library world in full swing. Meetings, committee discussions, schools at work, students busy with December and May examinations in view, and…
Abstract
MID‐OCTOBER sees the activities of the library world in full swing. Meetings, committee discussions, schools at work, students busy with December and May examinations in view, and a host of occupations for the library worker. This year—for in a sense the library year begins in October—will be a busy one. For the Library Association Council there will be the onerous business of preparing a report on State Control; for libraries there will be the effort to retain readers in a land of increasing employment and reduced leisure; and for the students, as we have remarked in earlier issues, preparations for the new syllabus of examinations which becomes operative in 1938. It is a good month, too, to consider some phases of library work with children, “which,” to quote the L.A. Resolutions of 1917, “ought to be the basis of all other library work.”
THERE ARE TIMES, you know, when I feel that there is nothing new to be said about technical college libraries. Perhaps in another few years we shall have some progress to report…
Abstract
THERE ARE TIMES, you know, when I feel that there is nothing new to be said about technical college libraries. Perhaps in another few years we shall have some progress to report, but, in the remote event of there being at present some development which has not been fully described, the person to do the job is probably not the librarian who is speaking to you now. He is very conscious that neither by years of experience nor by acquaintance with many different colleges is he qualified to survey technical college librarianship. Yet there may be some point in taking another look at fairly familiar territory, because some of you may have had little contact with college libraries, while others may have had relations with them different from those enjoyed by the librarian.
BY the time these words appear the majority of those who attend Library Association Conferences will have made tentative arrangements for their visit to Margate in June. Already…
Abstract
BY the time these words appear the majority of those who attend Library Association Conferences will have made tentative arrangements for their visit to Margate in June. Already, we understand, adhesions are coming in as many in number as for any September conference, and, if this is so, the fact will reassure those who have doubts of the wisdom of the change from September to June. We give on other pages some outline of the programme and in Letters on Our Affairs are presented with a Study of the subjects of the papers. Here we can concentrate upon one or two important points.
THIS journal is not devoted exclusively to public libraries; they are only part of the library fabric but, because the preponderant number of workers in our craft are in public…
Abstract
THIS journal is not devoted exclusively to public libraries; they are only part of the library fabric but, because the preponderant number of workers in our craft are in public libraries, they and their work naturally occur more often in our pages than do those of others. We have always urged that the profession is indivisable and that a librarian is a person who, in his fundamental training, should be equipped to serve in any kind of library. The tendency to create distinctions, based upon slight—and they usually are slight—differences of work, are unfortunate and have led to bickerings and sometimes recriminations. Even between the two arms of the public library service, the county and the urban, there has been an emphasis on the differences rather than the likenesses; and every wise librarian knows that the services of a fully‐engaged library in a town are exactly the same as those of a county except that the county has to cover longer distances. The emphasis is even stronger where public and nonpublic libraries are in question.
RETROSPECT is natural at the beginning of a new library year. All over the world of libraries of all kinds the shadow of the general depression has fallen; more heavily perhaps in…
Abstract
RETROSPECT is natural at the beginning of a new library year. All over the world of libraries of all kinds the shadow of the general depression has fallen; more heavily perhaps in the United States than here. It is a testing time which has made the enemies of libraries vocal and has also fortunately roused their advocates. On balance, optimism may prevail; and in that faith we wish our readers a happy new year.