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1 – 5 of 5GuoHua Gao, Han Ren, QiXiao Xia, Hao Wang and LianShi Li
The purpose of this paper is to present a stretched backboneless continuum manipulator, which aims to provide sufficient inner room for potential transportation of objects or…
Abstract
Purpose
The purpose of this paper is to present a stretched backboneless continuum manipulator, which aims to provide sufficient inner room for potential transportation of objects or fixture of necessary devices, and to reduce the number of motors for reduction of the weight of the system.
Design/methodology/approach
A mathematical model of the presented manipulator is established in this paper. To verify the presented theory, the position of the free end was recorded by a high-resolution digital camera in experiment. According to the comparison of experimental values and theoretical values, the error is less than 2.5 per cent. It shows that the mathematical model and theoretical analysis are reasonable; the presented continuum manipulator can reach to desired postures and positions.
Findings
This paper presents a new stretched backboneless continuum manipulator supported and driven by cannula tendons. The cannula tendons are composed of rubber tubes and glass fibers. The upper section and the lower section of the presented manipulator are driven by same motors. For steering the manipulator, switched driving strategy is developed based on the presented kinematics model. The presented manipulator possesses six degrees of freedom (DOFs) and has good performance in dealing with complex working environment. The experiment verifies the presented driving strategy.
Research limitations/implications
The presented backboneless continuum manipulator has only two sections and is supported by cannula tendons. Extending this structure to further more sections is a challenge and is left for future research.
Originality/value
The value of this study is to propose a stretched backboneless continuum manipulator, which can provide inner room as large as possible for potential usage and halve the number of motors, for which a switched driving strategy is put forward. As a result, the weight and complexity of the manipulator are decreased. The presented manipulator is able to move in potential complex environments and approach its objects in different postures in virtue of its high flexibility and its six DOFs.
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Keywords
Hao Wang, GuoHua Gao, Qixiao Xia, Han Ren, LianShi Li and Yuhang Zheng
The purpose of this paper is to present a novel stretch-retractable single section (SRSS) continuum manipulator which owns three degrees of freedom and higher motion range in…
Abstract
Purpose
The purpose of this paper is to present a novel stretch-retractable single section (SRSS) continuum manipulator which owns three degrees of freedom and higher motion range in three-dimension workspace than regular single continuum manipulator. Moreover, the motion accuracy was analyzed based on the kinematic model. In addition, the experiments were carried out for validation of the theory.
Design/methodology/approach
A kinematics model of the SRSS continuum manipulator is presented for analysis on bending, rotating and retracting in its workspace. To discuss the motion accuracy of the SRSS continuum manipulator, the dexterity theory was introduced based on the decomposing of the Jacobian matrix. In addition, the accuracy of motion is estimated based on the inverse kinematics and dexterity theory. To verify the presented theory, the motion of free end was tracked by an electromagnetic positioning system. According to the comparison of experimental value and theoretical analysis, the free end error of SRSS continuum manipulator is less than 6.24 per cent in the region with favorable dexterity.
Findings
This paper presents a new stretch-retractable continuum manipulator that the structure was composed of several springs as the backbone. Thus, the SRSS continuum manipulator could own wide motion range depending on its retractable structure. Then, the motion accuracy character of the SRSS continuum manipulator in the different regions of its workspace was obtained both theoretically and experimentally. The results show that the high accuracy region distributes in the vicinity of the outer boundary of the workspace. The motion accuracy gradually decreases with the motion position approaching to the center of its workspace.
Research limitations/implications
The presented SRSS continuum manipulator owns three degrees of freedom. The future work would be focused on the two-section structure which will own six degrees of freedom.
Practical implications
In this study, the SRSS continuum manipulator could be extended to six degrees of freedom continuum robot with two sections that is less one section than regular six degrees of freedom with three single section continuum manipulator.
Originality/value
The value of this study is to propose a SRSS continuum manipulator which owns three degrees of freedom and could stretch and retract to expend workspace, for which the accuracy in different regions of the workspace was analyzed and validated based on the kinematics model and experiments. The results could be feasible to plan the motion space of the SRSS continuum manipulator for keeping in suitable accuracy region.
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Shuntao Liu, Zhixiong Yang, Zhijun Zhu, Liangliang Han, Xiangyang Zhu and Kai Xu
Slim and dexterous manipulators with long reaches can perform various exploration and inspection tasks in confined spaces. This paper aims to present the development of such a…
Abstract
Purpose
Slim and dexterous manipulators with long reaches can perform various exploration and inspection tasks in confined spaces. This paper aims to present the development of such a dexterous continuum manipulator for potential applications in the aviation industry.
Design/methodology/approach
Benefiting from a newly conceived dual continuum mechanism and the improved actuation scheme, this paper proposes a design of a slim and dexterous continuum manipulator. Kinematics modeling, simulation-based dimension synthesis, structural constructions and system descriptions are elaborated.
Findings
Experimental validations show that the constructed prototype possesses the desired dexterity to navigate through confined spaces with its kinematics calibrated and actuation compensation implemented. The continuum manipulator with different deployed tools (e.g. graspers and welding guns) would be able to perform inspections and other tasks at remote locations in constrained environments.
Research limitations/implications
The current construction of the continuum manipulator possesses quite some friction inside its structure. The bending discrepancy caused by friction could accumulate to an obvious level. It is desired to further reduce the friction, even though the actuation compensation had been implemented.
Practical implications
The constructed continuum manipulator could perform inspection and other tasks in confined spaces, acting as an active multi-functional endoscopic platform. Such a device could greatly facilitate routine tasks in the aviation industry, such as guided assembling, inspection and maintenance.
Originality/value
The originality and values of this paper mainly lay on the design, modeling, construction and experimental validations of the slim and dexterous continuum manipulator for the desired mobility and functionality in confined spaces.
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This paper aims to trace the technological and commercial developments in robotics over the last 50 years, from 1973, the year in which this journal was founded, to the present…
Abstract
Purpose
This paper aims to trace the technological and commercial developments in robotics over the last 50 years, from 1973, the year in which this journal was founded, to the present day.
Design/methodology/approach
Following an introduction, this identifies key robot developments on a decade-by-decade basis and considers research, products, applications and corporate activity and also highlights many of the enabling technologies. Brief conclusions are draw.
Findings
The robot industry has changed beyond all recognition during the last half century. Enabled by developments in microelectronics, computing, sensors, imaging technologies, data communication and power sources, today robots satisfy a multitude of applications and play a role in almost every sphere of human activity.
Originality/value
This provides a detailed review of robotic developments during the last 50 years.
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Zhixiong Yang, Bin Zhao, Liang Bo, Xiangyang Zhu and Kai Xu
Pick-and-place tasks are common across many industrial sectors, and many rigid-linked robots have been proposed for this application. This paper aims to alternatively present the…
Abstract
Purpose
Pick-and-place tasks are common across many industrial sectors, and many rigid-linked robots have been proposed for this application. This paper aims to alternatively present the development of a continuum robot for low-load medium-speed pick-and-place tasks.
Design/methodology/approach
An inversion of a previously proposed dual continuum mechanism, as a key design element, was used to realize the horizontal movements of the CurviPicker’s end effector. A flexible shaft was inserted to realize rotation and translation about a vertical axis. The design concept, kinematics, system descriptions and proof-of-concept experimental characterizations are elaborated.
Findings
Experimental characterizations show that the CurviPicker can achieve satisfactory accuracy after motion calibration. The CurviPicker is easy to control due to its simple kinematics, while its structural compliance makes it safe to work with, as well as less sensitive to possible target picking position errors to avoid damaging itself or the to-be-picked objects.
Research limitations/implications
The vertical translation of the CurviPicker is currently realized by moving the flexible shaft. Insertion of the flexible shaft introduces possible disturbances. It is desired to explore other form of variations to use structural deformation to realize the vertical translation.
Practical implications
The proposed CurviPicker realizes the Schöenflies motions via a simple structure. Such a robot can be used to increase robot presence and automation in small businesses for low-load medium-speed pick-and-place tasks.
Originality/value
To the best of the authors’ knowledge, the CurviPicker is the first continuum robot designed and constructed for pick-and-place tasks. The originality stems from the concept, kinematics, development and proof-of-concept experimental characterizations of the CurviPicker.
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