A cable-driven parallel manipulator with force sensing capabilities for high-accuracy tissue endomicroscopy

A kind of 2-DOF parallel manipulator driven by two sliders moving along two parallel guides is analyzed. Based on the explicit expression of inverse position, velocity and acceleration analyses, the mobile trajectory of this manipulator is investigated and simulated. In trajectory planning, the trajectory profiles are assigned to be accelerated and decelerated at the first and last few seconds, respectively, and keep at constant speed for the remainder of time, where the forth-order polynomial is fitted during acceleration and deceleration, and clothoid curve is applied around the corner of axis. Then the mobile rule exerted on the actuator sliders is obtained using inverse position based on the desired end-effecter trajectory. Finally, the virtual prototype of this mechanism is modeled using Solidwork and the kinematics and dynamics simulation is performed using Cosmostion. The result shows that both velocity, acceleration of the sliders and the driving force exerted on the sliders are continuous curves, which can fully satisfy the demand of high-accuracy and real-time processing of the high-speed Manipulator.

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Kinematic calibration and error compensation of a hexaglide parallel manipulator

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405417713235 ◽

2017 ◽

Vol 233 (1) ◽

pp. 215-225 ◽

Cited By ~ 5

Author(s):

Jiangzhen Guo ◽

Dan Wang ◽

Rui Fan ◽

Wuyi Chen ◽

Guohua Zhao

Keyword(s):

Error Compensation ◽

Parallel Manipulator ◽

Least Squares Method ◽

Orthogonal Design ◽

Kinematic Model ◽

Calibration Method ◽

High Accuracy ◽

Geometric Error ◽

Kinematic Calibration ◽

Parallel Mechanisms

A calibration method of a hexaglide parallel manipulator is presented to improve its accuracy. A prototype of the hexaglide parallel manipulator is first proposed and its kinematics is analyzed. Through differentiating kinematic equations, 54 geometric error parameters are generated to present the pose error of the moving platform, on which an iterative algorithm for the calibration is based. The experiment starts with the data acquisition. All of measuring poses are newly selected based on the orthogonal design, and the deviations in each pose are measured by a laser tracker. Subsequently, 54 actual geometric parameters are identified by least squares method and compensated to the nominal kinematic model, which is assessed by 25 configurations to obtain the accuracy of the calibrated hexaglide parallel manipulator. It is discovered that the pose errors of the calibrated hexaglide parallel manipulator are significantly reduced and illustrate the validity of the calibration method to improve its accuracy. Finally, we discussed the feasibility of implementing this method in high-accuracy calibration of variant-scale parallel mechanisms.

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A Transformation Method to Generate the Workspace of an n(3RRS) Serial–Parallel Manipulator

Journal of Mechanical Design ◽

10.1115/1.4042625 ◽

2019 ◽

Vol 141 (9) ◽

Cited By ~ 1

Author(s):

Hongwei Guo ◽

Chong Zhao ◽

Bing Li ◽

Rongqiang Liu ◽

Zongquan Deng ◽

...

Keyword(s):

Parallel Manipulator ◽

High Efficiency ◽

Transformation Method ◽

High Accuracy ◽

Search Method ◽

Simple Operation ◽

In Series

This paper presents a transformation method to generate the workspace of an n(3RRS) serial–parallel manipulator (S–PM). Firstly, the boundary of the workspace of the 3RRS parallel manipulator (PM) is obtained using the boundary search method and verified by MATLAB/SimMechanics simulation. Secondly, the workspace of the 2(3RRS) S–PM is obtained using the proposed method and verified by MATLAB/SimMechanics simulation. Finally, the workspace of the 3(3RRS) S–PM is obtained using the proposed method. The results indicate that the n(3RRS) S–PM can significantly expand its workspace with the increase in the number of PMs connected in series, and the proposed method can generate the workspaces of n(3RRS) S–PMs efficiently with the advantages of simple operation, high efficiency, and high accuracy. The proposed method is applicable to all S–PMs that are composed of PMs, and it provides a reference for solving the workspaces of other types of redundantly hybrid manipulators.

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A new asymmetrical mass distribution method on the analysis of universal “force-sensing” model for 3-DOF translational parallel manipulator

Industrial Robot the international journal of robotics research and application ◽

10.1108/ir-03-2013-337 ◽

2014 ◽

Vol 41 (1) ◽

pp. 56-69 ◽

Cited By ~ 4

Author(s):

Lingtao Yu ◽

Huajian Song ◽

Tao Wang ◽

Zhengyu Wang ◽

Liqiang Sun ◽

...

Keyword(s):

Mass Distribution ◽

Physical Meaning ◽

Parallel Manipulator ◽

Force Feedback ◽

Static Model ◽

Force Sensing ◽

Omega 3 ◽

Distribution Method ◽

Content Type ◽

Sensing Model

Purpose – The characteristic of static is quite important especially for the manipulator with force feedback. This paper aims to improve the traditional static model by considering the limitations such as lacking of versatility and ignoring gravity of links. For this purpose, a new asymmetric mass distribution method on the analysis of universal “force-sensing” model has been put forward to overcome the limitations. Design/methodology/approach – Through the forces and torques analysis of every link and the moving platform, the static model of 3-RUU manipulator is acquired. Then, based on the physical meaning analysis of every part in the static model of 3-RUU manipulator, a new asymmetric mass distribution method on the analysis of universal “force-sensing” model can be obtained. Findings – The correctness of the static model of 3-RUU manipulator is verified by simulation results based on Pro/Engineer software and Adams software. Furthermore, experiment results based on a manipulator similar to the Omega.3 manipulator indicate that the universal “force-sensing” model can be applicable to the above manipulator. Originality/value – A new asymmetric mass distribution method on the analysis of universal static mathematical model has been put forward. Based on physical meaning of the above method, the “force-sensing” model can be established quickly and it owns versatility, which can be applicable to the 3-RUU manipulator, the Omega.3 parallel manipulator and other similar manipulators with force feedback. In addition, it can improve the accuracy of the “force-sensing” model to a great extent.

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Statics Analysis of a Novel 5-DOF Parallel Manipulator

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.102-104.311 ◽

2010 ◽

Vol 102-104 ◽

pp. 311-315

Author(s):

Yan Biao Li ◽

Shi Ming Ji ◽

Zhong Fei Wang ◽

Li Zhang ◽

Yang Yu Wang

Keyword(s):

Machine Tool ◽

Parallel Manipulator ◽

Parallel Machine ◽

High Accuracy ◽

Theoretical Base ◽

The Novel ◽

High Stiffness ◽

Technological Efficiency ◽

Parallel Machine Tool

A novel orthogonal 5-DOF parallel manipulator was proposed, and the statics equations of the 5-DOF parallel manipulator were derived in closed forms based on its layout feature, then the statics transmission indices wer defined, and discussed in detail. It can provide theoretical base for the applications of the 5-DOF parallel machine tool. The novel 5-DOF parallel manipulator can be used as the precision platform in which the requirements for high stiffness, high accuracy and good technological efficiency.

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A New 1,000 kV Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061318 ◽

1967 ◽

Vol 25 ◽

pp. 260-261

Author(s):

M. Nishigaki ◽

S. Katagiri ◽

H. Kimura ◽

B. Tadano

Keyword(s):

Electron Microscope ◽

High Voltage ◽

Basic Research ◽

Chromatic Aberration ◽

High Accuracy ◽

Biological Specimen ◽

Voltage Electron ◽

High Voltage Electron Microscope ◽

High Voltage Electron

The high voltage electron microscope has many advantageous features in comparison with the ordinary electron microscope. They are a higher penetrating efficiency of the electron, low chromatic aberration, high accuracy of the selected area diffraction and so on. Thus, the high voltage electron microscope becomes an indispensable instrument for the metallurgical, polymer and biological specimen studies. The application of the instrument involves today not only basic research but routine survey in the various fields. Particularly for the latter purpose, the performance, maintenance and reliability of the microscope should be same as those of commercial ones. The authors completed a 500 kV electron microscope in 1964 and a 1,000 kV one in 1966 taking these points into consideration. The construction of our 1,000 kV electron microscope is described below.

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