Cartesian space dynamic model of serial-parallel manipulator systems and their dynamic performance evaluation

In this work the dynamic performance and control of a 2DOF parallel robot is conducted. The study is partly motivated by large variations in dynamic performance and control within the reachable workspace of many parallel manipulators. The forward dynamic model of the robot is derived in detail. The connection method is directly utilized for this derivation. Subsequently, a dynamic performance study is undertaken. This reveals important information whilst using a forward dynamic model. A performance index is proposed to determine the variability of performance of the parallel manipulator. Then a trajectory-tracking scenario is undertaken using a linear controller. By means of control, the simulations illustrate the validity of the proposed index for parallel manipulators.

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Integrating Dynamics into Design and Motion Optimization of a 3-PRR Planar Parallel Manipulator with Discrete Time Transfer Matrix Method

Mathematical Problems in Engineering ◽

10.1155/2020/2761508 ◽

2020 ◽

Vol 2020 ◽

pp. 1-23 ◽

Cited By ~ 3

Author(s):

Guoning Si ◽

Mengqiu Chu ◽

Zhuo Zhang ◽

Haijie Li ◽

Xuping Zhang

Keyword(s):

Dynamic Model ◽

Dynamic Modeling ◽

Discrete Time ◽

Parallel Manipulator ◽

Robot Manipulators ◽

Dynamic Performance ◽

Parallel Robot ◽

Time Transfer ◽

Performance Indices ◽

Planar Parallel Manipulator

This paper presents a novel method of dynamic modeling and design optimization integrated with dynamics for parallel robot manipulators. Firstly, a computationally efficient modeling method, the discrete time transfer matrix method (DT-TMM), is proposed to establish the dynamic model of a 3-PRR planar parallel manipulator (PPM) for the first time. The numerical simulations are performed with both the proposed DT-TMM dynamic modeling and the ADAMS modeling. The applicability and effectiveness of DT-TMM in parallel manipulators are verified by comparing the numerical results. Secondly, the design parameters of the 3-PRR parallel manipulator are optimized using the kinematic performance indices, such as global workspace conditioning index (GWCI), global condition index (GCI), and global gradient index (GGI). Finally, a dynamic performance index, namely, driving force index (DFI), is proposed based on the established dynamic model. The described motion trajectory of the moving platform is placed into the optimized workspace and the initial position is determined to finalize the end-effector trajectory of the parallel manipulator by the further optimization with the integrated kinematic and dynamic performance indices. The novelty of this work includes (1) developing a new dynamic model method with high computation efficiency for parallel robot manipulators using DT-TMM and (2) proposing a new dynamic performance index and integrating the dynamic index into the motion and design optimization of parallel robot manipulators.

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Dynamic Performance Evaluation of a Parallel Manipulator with Non Axial Symmetrical Characteristics by Computing the Respective Actuating Joint Capability

International Journal of Intelligent Mechatronics and Robotics ◽

10.4018/ijimr.2012100101 ◽

2012 ◽

Vol 2 (4) ◽

pp. 1-14

Author(s):

Yongjie Zhao ◽

Yanling Tian

Keyword(s):

Performance Evaluation ◽

Parallel Manipulator ◽

Dynamic Performance ◽

Parallel Manipulators ◽

Joint Torque ◽

Power Indices ◽

Joint Power ◽

Symmetrical Structure ◽

Capability Evaluation ◽

Power Capability

Unlike the traditional Gough-Stewart platform with axial symmetrical structure, a parallel manipulator consists of non axial symmetrical structure has non axial symmetrical characteristic in the whole reachable workspace. This paper presents the joint capability evaluation of a parallel manipulator with non axial symmetrical characteristics. A series of velocity, torque and power indices are presented. The torque indices combining the acceleration, velocity, and gravity components of the dynamic model are used to evaluate the respective joint torque capability. The power indices corresponding to the torque indices are also adopted to evaluate the respective joint power capability. The joint capability evaluation of the parallel manipulator is carried out through computational analysis and simulation with the velocity, torque and power indices. It is shown that the respective actuating joint capabilities of the parallel manipulator are not uniform due to the non axial symmetrical structure. Thus the performance evaluation of this type of parallel manipulator must be performed by analyzing the respective joint capability. By means of these indices with obvious physical meanings, it is possible to control the respective joint capability of the parallel manipulator. The indices are general and can be used for the other types of parallel manipulators.

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Dynamic Performance Evaluation of a Redundantly Actuated and Over-constrained Parallel Manipulator

International Journal of Automation and Computing ◽

10.1007/s11633-018-1147-6 ◽

2018 ◽

Vol 16 (3) ◽

pp. 274-285 ◽

Cited By ~ 11

Author(s):

Hai-Qiang Zhang ◽

Hai-Rong Fang ◽

Bing-Shan Jiang ◽

Shuai-Guo Wang

Keyword(s):

Performance Evaluation ◽

Parallel Manipulator ◽

Dynamic Performance ◽

Redundantly Actuated

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Rigid–flexible coupling dynamics analysis with joint clearance for a 5-DOF hybrid polishing robot

Robotica ◽

10.1017/s0263574721001594 ◽

2021 ◽

pp. 1-21

Author(s):

Feng Guo ◽

Gang Cheng ◽

Shilin Wang ◽

Jun Li

Keyword(s):

Dynamic Model ◽

Parallel Manipulator ◽

Dynamic Properties ◽

Dynamic Performance ◽

Joint Clearance ◽

Motion Error ◽

Flexible Coupling ◽

Coupling Dynamic ◽

Equivalent Load ◽

Coupling Dynamic Model

SUMMARY Considering the polishing requirements for high-precision aspherical optical mirrors, a hybrid polishing robot composed of a serial–parallel manipulator and a dual rotor grinding system is proposed. Firstly, based on the kinematics of serial components, the equivalent load model for the parallel manipulator is established. Then, the elastodynamic model of kinematic branched-chains of the parallel manipulator is established by using the spatial beam element, and the rigid–flexible coupling dynamic model of the polishing robot is obtained with Kineto-elasto dynamics theory. Further, considering the dynamic properties of the joint clearance, the rigid–flexible coupling dynamic model with the joint clearance for the polishing robot is established. Finally, the equivalent load distribution of the parallel manipulator is analyzed, and the effect of the branched-chain elasticity and joint clearance on the motion error of the polishing robot is studied. This article provides a theoretical basis for improving the motion accuracy and dynamic performance of the hybrid polishing robot.

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Inductor Saturation Compensation in Three-Phase Three-Wire Voltage-Source Converters via Inverse System Dynamics-I

10.36227/techrxiv.12378371 ◽

2020 ◽

Author(s):

Ziya Özkan ◽

Ahmet Masum Hava

Keyword(s):

Dynamic Model ◽

Dynamic Performance ◽

Current Control ◽

Inverse System ◽

Voltage Source ◽

Voltage Source Converter ◽

Two Phase ◽

Inverse Dynamic ◽

Three Phase ◽

Steady State Current

In three-phase three-wire (3P3W) voltage-source converter (VSC) systems, utilization of filter inductors with deep saturation characteristics is often advantageous due to the improved size, cost, and efficiency. However, with the use of conventional synchronous frame current control (CSCC) methods, the inductor saturation results in significant dynamic performance loss and poor steady-state current waveform quality. This paper proposes an inverse dynamic model based compensation (IDMBC) method to overcome these performance issues. Accordingly, a review of inductor saturation and core materials is performed, and the motivation on the use of saturable inductors is clarified. Then, two-phase exact modelling of the 3P3W VSC control system is obtained and the drawbacks of CSCC have been demonstrated analytically. Based on the exact modelling, the inverse system dynamic model of the nonlinear system is obtained and employed such that the nonlinear plant is converted to a fictitious linear inductor system for linear current regulators to perform satisfactorily.

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Performance evaluation of a special 6-PUS type parallel manipulator

Robotica ◽

10.1017/s0263574721000655 ◽

2021 ◽

pp. 1-15

Author(s):

Xiaochu Liu ◽

Yunfei Cai ◽

Weitian Liu ◽

Linlong Zhang ◽

Chengxin Hu

Keyword(s):

Performance Evaluation ◽

Natural Frequency ◽

Parallel Manipulator ◽

Screw Theory ◽

Shaking Table ◽

Axial Stiffness ◽

Neutral Position ◽

Dynamics Model ◽

Force Transmissibility ◽

Kane Method

Abstract In this paper, a special 6-PUS parallel manipulator (PM) is utilized as a shaking table. Unlike the existing results about 6-PUS PMs, we make the actuator direction collinear with the linkage direction at neutral position. With respect to the application background, a further analysis of the special PM is carried out from the perspective of motion/force transmissibility, natural frequency and acceleration capability. Specially, the complete dynamics model is established based on the Kane method. Then, generalized transmission indices based on the screw theory are utilized to reflect its motion ability, and a model of natural frequency is proposed with the axial stiffness of linkages considered. Finally, the effect of the angle between the actuator direction and the linkage direction α on various performances is analyzed, and other results are included to illustrate its feasibility and usability.

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Numerical Investigation on Hydrodynamic Performance of a Portable AUV

Journal of Marine Science and Engineering ◽

10.3390/jmse9080812 ◽

2021 ◽

Vol 9 (8) ◽

pp. 812

Author(s):

Lin Hong ◽

Renjie Fang ◽

Xiaotian Cai ◽

Xin Wang

Keyword(s):

Numerical Investigation ◽

Dynamic Model ◽

Autonomous Underwater Vehicle ◽

Dynamic Performance ◽

Plane Motion ◽

Hydrodynamic Performance ◽

Wave Forces ◽

Modeling And Control ◽

Experiment Platform ◽

Cfd Method

This paper conducts a numerical investigation on the hydrodynamic performance of a portable autonomous underwater vehicle (AUV). The portable AUV is designed to cruise and perform some tasks autonomously in the underwater world. However, its dynamic performance is strongly affected by hydrodynamic effects. Therefore, it is crucial to investigate the hydrodynamic performance of the portable AUV for its accurate dynamic modeling and control. In this work, based on the designed portable AUV, a comprehensive hydrodynamic performance investigation was conducted by adopting the computational fluid dynamics (CFD) method. Firstly, the mechanical structure of the portable AUV was briefly introduced, and the dynamic model of the AUV, including the hydrodynamic term, was established. Then, the unknown hydrodynamic coefficients in the dynamic model were estimated through the towing experiment and the plane-motion-mechanism (PMM) experiment simulation. In addition, considering that the portable AUV was affected by wave forces when cruising near the water surface, the influence of surface waves on the hydrodynamic performance of the AUV under different wave conditions and submerged depths was analyzed. Finally, the effectiveness of our method was verified by experiments on the standard models, and a physical experiment platform was built in this work to facilitate hydrodynamic performance investigations of some portable small-size AUVs.

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