A 6-DOF Compliant Joints-Based Precision Parallel Positioner System Driven by Dual Piezoelectric Actuators

2007 ◽  
Author(s):  
Wei Dong ◽  
Zhijiang Du ◽  
Lining Sun
Keyword(s):  
Parallel Mechanism ◽  
Load Capacity ◽  
Piezoelectric Actuators ◽  
Piezoelectric Ceramics ◽  
Parallel Structure ◽  
Nanometer Scale ◽  
Compliant Joints ◽  
Piezoelectric Motors ◽  
Motion Range ◽  
Large Motion

A precision compliant parallel-structure positioner is presented in this paper, which is dually driven by six piezoelectric motors and six piezoelectric ceramics respectively. This compliant system has a load capacity higher than 2 kg because the parallel mechanism is adopted as the main architecture. This system also can provide larger workspace and higher accuracy simultaneously compared with the conventional compliant positioner systems, because it perfectly integrates two kinds of piezoelectric actuators in one parallel system. The upper platform has the stroke of 10 mm in three linear motion directions and of 6 arc-degrees in three angle motion directions respectively for the adoption of piezoelectric motors as the large motion range actuators. The positioning resolution and repeatability of the upper platform is nanometer scale for the adoption of piezoelectric ceramics as the high precision actuators.

Design of Large Motion Range and Heavy Duty 2-DOF Spherical Parallel Wrist Mechanism

2013 ◽  
Vol 25 (2) ◽  
pp. 294-305 ◽  
Author(s):  
Koji Ueda ◽  
◽  
Hiroya Yamada ◽  
Hiroaki Ishida ◽  
Shigeo Hirose ◽  
...  
Keyword(s):  
Load Capacity ◽  
Heavy Duty ◽  
Universal Joint ◽  
Compact Structure ◽  
Robotic Arms ◽  
Rescue Robot ◽  
Wide Range ◽  
Spherical Parallel Mechanism ◽  
Motion Range ◽  
Large Motion

Wrist mechanisms are important elements of robotic arms because they significantly affect the arm’s handling ability. Although various wrist mechanisms have been developed to date, a mechanism with a compact structure, a wide range of motion and a large load capacity has not yet been realized. Thus, in this paper, we propose 2-DOF Spherical Parallel (2DSP) mechanism, a heavy-duty wrist mechanism with a large motion range, and clarify its features both analytically and experimentally. The 2DSP mechanism is driven by a 2-DOF spherical parallel mechanism and is supported by a universal joint located at its center. This structure allows the 2DSP mechanism to realize a large motion range and load capacity and simplifies its kinematic analysis. Based on this analysis, we clarify the design process to maximize the motion range and propose a preferable structure of passive joints from the viewpoint of load capacity and production cost. We also describe the detailed design of a 2DSP mechanism for a rescue robot we developed previously and verify the feasibility of the proposed mechanism.

Novel Type of Hybrid 3-DOF Micromanipulator with Piezoelectric Actuators – Mechanical Construction and Simulations

2009 ◽  
Vol 147-149 ◽  
pp. 19-24 ◽  
Author(s):  
Daniel Prusak ◽  
Tadeusz Uhl
Keyword(s):  
Control System ◽  
Degrees Of Freedom ◽  
Piezoelectric Actuators ◽  
Parallel Structure ◽  
Range Of Movement ◽  
Fe Method ◽  
Compliant Joints ◽  
Micro Robot ◽  
Moving Platform ◽  
Hybrid Construction

The paper reports on the main assumptions and guidelines regarding construction of a novel type of parallel micro-robot with 3 degrees of freedom. Such micromanipulator is a hybrid construction, consisting of three arms connected together in parallel structure. The mechanical construction is a combination of rotational joints with bearings and flexible compliant joints so called: flexures. The whole construction measures several cubic centimeters and operates within c.a. 4 cubic centimeters workspace. In addition, the article relates to selected aspects of the control system, mathematical analysis of kinematics, basic simulations, specification of the range of movement of all actuators, and workspace of the moving platform. Modeling flexures using FE method will also be presented.

scholarly journals Design and Analysis of a Novel Piezo-Actuated XYθz Micropositioning Mechanism with Large Travel and Kinematic Decoupling

2019 ◽  
Vol 2019 ◽  
pp. 1-15
Author(s):  
Ruijiang Xiao ◽  
Shubao Shao ◽  
Minglong Xu ◽  
Zijian Jing
Keyword(s):  
Piezoelectric Actuators ◽  
Output Coupling ◽  
Rotational Angle ◽  
Output Displacement ◽  
Compact Size ◽  
Motion Range ◽  
Rotational Part ◽  
Large Motion ◽  
Amplification Mechanism ◽  
Nonuniform Beam

A novel hybrid-type XYθz micropositioning mechanism driven by piezoelectric actuators is proposed in this paper. With the purpose of realizing a large motion range and 3-DoF independent motion within a compact size, the mechanism is designed using a symmetric translational part and a rotational part that are linked serially. The translational part is based on a double-amplification mechanism incorporating a guidance mechanism for decoupling; the rotational part uses a nonuniform beam with an amplification mechanism to translate the linear output displacement of piezoelectric actuators into a large rotational angle around the Z axis. To precisely predict the output displacements and implement dimensional design, electromechanical models of the translational mechanism and rotational mechanism are established. According to the theoretical model, dimensional optimization is carried out to achieve large motion ranges within a compact size. A prototype of the proposed mechanism is fabricated according to the optimized results, and the performance of the mechanism is validated by experiment. The experimental results show that translational travel in X and Y directions of 204.2 μm and 212.8 μm, respectively, and travel of 8.7 mrad in the θz direction can be realized in a small size of 106 mm × 106 mm × 23 mm. And, the output coupling was evaluated to be below 3%, indicating an excellent decoupling performance.

Experimental Validation of the Kinematics of a 3PRS Compliant Mechanism for Micromilling

2015 ◽  
Author(s):  
Antonio Ruiz ◽  
Francisco Campa Gomez ◽  
Constantino Roldan-Paraponiaris ◽  
Oscar Altuzarra
Keyword(s):  
Parallel Mechanism ◽  
Degrees Of Freedom ◽  
Experimental Validation ◽  
Compliant Mechanism ◽  
Motion Controller ◽  
End Effector ◽  
Compliant Joints ◽  
Hybrid Manipulator ◽  
Compliant Parallel Mechanism ◽  
Actuated Joints

The present work deals with the development of a hybrid manipulator of 5 degrees of freedom for milling moulds for microlenses. The manipulator is based on a XY stage under a 3PRS compliant parallel mechanism. The mechanism takes advantage of the compliant joints to achieve higher repetitiveness, smoother motion and a higher bandwidth, due to the high precision demanded from the process, under 0.1 micrometers. This work is focused on the kinematics of the compliant stage of the hybrid manipulator. First, an analysis of the workspace required for the milling of a single mould has been performed, calculating the displacements required in X, Y, Z axis as well as two relative rotations between the tool and the workpiece from a programmed toolpath. Then, the 3PRS compliant parallel mechanism has been designed using FEM with the objective of being stiff enough to support the cutting forces from the micromilling, but flexible enough in the revolution and spherical compliant joints to provide the displacements needed. Finally, a prototype of the 3PRS compliant mechanism has been built, implementing a motion controller to perform translations in Z direction and two rotations. The resulting displacements in the end effector and the actuated joints have been measured and compared with the FEM calculations and with the rigid body kinematics of the 3PRS.

scholarly journals Design and Analysis of a Flexible, Elastic, and Rope-Driven Parallel Mechanism for Wrist Rehabilitation

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Zaixiang Pang ◽  
Tongyu Wang ◽  
Junzhi Yu ◽  
Shuai Liu ◽  
Xiyu Zhang ◽  
...  
Keyword(s):  
Inverse Kinematics ◽  
Parallel Mechanism ◽  
Inverse Kinematic ◽  
Parallel Structure ◽  
Flexible Joints ◽  
Rehabilitation Robots ◽  
Hybrid Mechanism ◽  
Compression Spring ◽  
Moving Platform

This paper proposes a bionic flexible wrist parallel mechanism to simulate human wrist joints, which is characterized by a rope-driven, compression spring-supported hybrid mechanism. Specifically, to realize the movement of the wrist mechanism, a parallel structure is adopted to support the mobile platform and is controlled by a cable, which plays the role of wrist muscles. Because the compression spring is elastic, it is difficult to directly solve inverse kinematics. To address this problem, the external force acting on the moving platform is firstly equivalent to the vector force and torque at the center of the moving platform. Then, based on inverse kinematic and static analyses, the inverse motion of the robot model can be solved according to the force and torque balance conditions and the lateral spring bending equation of the compression spring. In order to verify the proposed method, kinematics, statics, and parallel mechanism workspace are further analyzed by the software MATLAB. The obtained results demonstrate the effectiveness and feasibility of the designed parallel mechanism. This work offers new insights into the parallel mechanism with flexible joints in replicating the movements of the human wrist, thus promoting the development of rehabilitation robots and rope-driven technology to some extent.

scholarly journals A Compliant-Parallel Mechanism with Bio-Inspired Compliant Joints for High Precision Assembly Robot

Procedia CIRP ◽  
2013 ◽  
Vol 5 ◽  
pp. 175-178 ◽  
Author(s):  
Hiroaki Kozuka ◽  
Jumpei Arata ◽  
Kenji Okuda ◽  
Akinori Onaga ◽  
Motoshi Ohno ◽  
...  
Keyword(s):  
High Precision ◽  
Parallel Mechanism ◽  
Compliant Joints ◽  
Compliant Parallel Mechanism

Determining the Driving Torques of the Robots with Delta 3DOF Parallel Structure by Using the MSC ADAMS Software Pack

2013 ◽  
Vol 332 ◽  
pp. 224-228 ◽  
Author(s):  
Dragoș Andrioaia ◽  
Dan Rotar ◽  
Gabriel Puiu
Keyword(s):  
Parallel Mechanism ◽  
Parallel Structure ◽  
High Stiffness ◽  
Adams Software ◽  
Software Pack ◽  
Driving Torque

During the latest years the parallel structure robots have been used more and more due to their advantages that consist of: high stiffness, availability for usage at higher speed and acceleration rates. In general these robots are used for handling light objects [. For choosing the driving servomotors of the robots, the maximum torques needed for the parallel mechanism to transport an object of a certain weight, along a trajectory, at a certain speed and acceleration, have to be considered. In this work the authors are approaching the study of the variation of the driving torques of the robots with parallel structure Delta 3DOF along a trajectory, in order to select the driving servomotors [2]. For analyzing the driving torque variations along a trajectory the MSC Adams software pack has been used.

Sign in / Sign up

Export Citation Format

Share Document