Trajectory Planning of a Novel 2-DoF High-Speed Planar Parallel Manipulator

2008 ◽  
pp. 199-207 ◽  
Author(s):  
Junfeng Hu ◽  
Xianmin Zhang ◽  
Jinqing Zhan
Keyword(s):  
Trajectory Planning ◽  
Parallel Manipulator ◽  
High Speed ◽  
Planar Parallel Manipulator

Integrated optimal design of a high-speed planar parallel manipulator

2018 ◽  
Vol 233 (9) ◽  
pp. 2976-2990 ◽  
Author(s):  
Zhengsheng Chen ◽  
Minxiu Kong
Keyword(s):  
Optimal Design ◽  
Parallel Manipulator ◽  
High Speed ◽  
Design Method ◽  
Tracking Error ◽  
Dimensional Synthesis ◽  
Tracking Accuracy ◽  
Nsga Ii ◽  
Parameters Tuning ◽  
Planar Parallel Manipulator

To obtain excellent comprehensive performances of the planar parallel manipulator for the high-speed application, an integrated optimal design method, which integrated dimensional synthesis, motors/reducers selection, and control parameters tuning, is proposed, and the 3RRR parallel manipulator was taken as the example. The kinematic and dynamic performances of condition number, velocity index, acceleration capability, and low-order frequency are taken into accounts for the dimensional synthesis. Then, to match motors/reducers parameters and keep an economical cost, the constraint equations and the parameters library are built, and the cost is chosen as one of the optimization objectives. Also, to get high tracking accuracy, the dynamic forward plus proportional–derivative control scheme is introduced, and the tracking error is chosen as one of the optimization objectives. Hence, the optimization model including dimensional synthesis, motors/reducers selection and controller parameters tuning is established, which is solved by the genetic algorithm II (NSGA-II). The result shows that comprehensive performances can be effectively promoted through the proposed integrated optimal design, and the prototype was constructed according to the Pareto-optimal front.

Adaptive Synchronized Control for a Planar Parallel Manipulator: Theory and Experiments

2005 ◽  
Vol 128 (4) ◽  
pp. 976-979 ◽  
Author(s):  
Lu Ren ◽  
James K. Mills ◽  
Dong Sun
Keyword(s):  
Parallel Manipulator ◽  
High Speed ◽  
Control Method ◽  
Parametric Uncertainty ◽  
Synchronization Error ◽  
Tracking Accuracy ◽  
Unknown Parameters ◽  
High Acceleration ◽  
Planar Parallel Manipulator ◽  
Synchronized Control

In this paper, we develop a new control method, termed adaptive synchronized (A-S) control, for improving tracking accuracy of a P-R-R type planar parallel manipulator with parametric uncertainty. The novelty of A-S control, a combination of synchronized control and adaptive control, is in the application of synchronized control to a single parallel manipulator so that tracking accuracy is improved during high-speed, high-acceleration tracking motions. Through treatment of each chain as a submanipulator; the P-R-R manipulator is thus modeled as a multi-robot system comprised of three submanipulators grasping a common payload. Considering the geometry of the platform, these submanipulators are kinematically constrained and move in a synchronous manner. To solve this synchronization control problem, a synchronization error is defined, which represents the coupling effects among the submanipulators. With the employment of this synchronization error, tracking accuracy of the platform is improved. Simultaneously, the estimated unknown parameters converge to their true values through the use of a bounded-gain-forgetting estimator. Experiments conducted on the P-R-R manipulator demonstrate the validity of the approach.

Dynamics of a Flexible-Link Planar Parallel Manipulator in Cartesian Space

1994 ◽  
Author(s):  
Abbas Fattah ◽  
Arun K. Misra ◽  
Jorge Angeles
Keyword(s):  
Parallel Manipulator ◽  
High Speed ◽  
Inverse Dynamics ◽  
Equations Of Motion ◽  
Flexible Link ◽  
End Effector ◽  
Joint Torques ◽  
Flexible Links ◽  
Cartesian Space ◽  
Planar Parallel Manipulator

Abstract The subject of this paper is the modeling and simulation of a flexible-link planar parallel manipulator in Cartesian space. Given a desired end-effector motion, the inverse kinematics and inverse dynamics of a rigid-link model of the parallel manipulator is used to obtain actuated joint torques. The actual end-effector motion and vibration of the flexible links are obtained using simulation (direct dynamics) for the flexible-link manipulator. Finite elements are used to model the flexible links, while the Euler-Lagrange formulation is used to derive the equations of motion of the uncoupled links. The equations of motion of all the links are assembled to obtain the governing equations for the entire system. The methodology of the natural orthogonal complement, which has been previously applied to flexible-link systems with open-chain structures, is used here to eliminate the constraint forces. Finally, geometric nonlinearities in elastic deformations, which are very important in high-speed operations, are also considered.

Bond Graph Modeling and Simulating of 3 RPR Planar Parallel Manipulator

2014 ◽  
Author(s):  
Cheng Yin ◽  
Shengqi Jian ◽  
Md. Hassan Faghih ◽  
Md. Toufiqul Islam ◽  
Luc Rolland
Keyword(s):  
Parallel Manipulator ◽  
High Speed ◽  
Reference Frames ◽  
Bond Graph ◽  
Dynamics Simulation ◽  
Bond Graphs ◽  
End Effector ◽  
Planar Parallel Manipulator ◽  
Bond Graph Modeling ◽  
Graph System

A 3-RPR planar parallel robot is a kind of planar mechanisms, which can work at high speed, with high accuracy and high rigidity. In this paper, a multi-body bond graph system will be built for the 3-RPR planar parallel manipulator (PPM), along with 3 PID controllers which give commands to 3 DC motors respectively. The advantage of bond graphs is that they can integrate different types of dynamics systems, the manipulator, the control and the motor can be modelled and simulated altogether in the same process. Bond graph will be established for each rigid body with body-fixed coordinate’s reference frames, which are connected with parasitic elements (damping and compliance) to each other. The PID set-point signals are generated by the explicit inverse kinematic equations. The 3 prismatic lengths constitute the measured feedback signals. In order to make the end-effector reach the ideal position with target orientation, the three links should reach the target lengths simultaneously. In this study, the dynamics simulation of 3-RPR PPM is conducted after building the bond graph system. As the 3 motors are working simultaneously and independently, the end-effector will arrive to the expected position. Finally, the bond graph and control system are validated with the compiled results and 3D animation. Force plot and torque plot will be generated as dynamics performance. Moreover, kinematics of manipulators are also calculated using bond graph. Eventually, bond graphs are shown to be effective in solving not only dynamic but also kinematic problems.

Realization and Simulation of Motion Trajectory of a 2-DOF Planar Parallel Manipulator

2011 ◽  
Vol 467-469 ◽  
pp. 1351-1356
Author(s):  
Xiao Rong Zhu ◽  
Hui Ping Shen ◽  
Wei Zhu
Keyword(s):  
Parallel Manipulator ◽  
High Speed ◽  
High Accuracy ◽  
Dynamics Simulation ◽  
Real Time Processing ◽  
Time Processing ◽  
Planar Parallel Manipulator ◽  
Order Polynomial ◽  
Acceleration And Deceleration ◽  
Continuous Curves

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.

Two-time scale controller design for a high speed planar parallel manipulator with structural flexibility

Robotica ◽  
2002 ◽  
Vol 20 (5) ◽  
pp. 519-528
Author(s):  
Bongsoo Kang ◽  
Benny Yeung ◽  
James K. Mills
Keyword(s):  
Time Scale ◽  
Parallel Manipulator ◽  
High Speed ◽  
Parallel Manipulators ◽  
Structural Vibration ◽  
Scale Model ◽  
Fast Time ◽  
Inertial Forces ◽  
Linear Quadratic ◽  
Planar Parallel Manipulator

SummaryPlanar parallel manipulators, with potential applications in high speed, high acceleration tasks such as electronic component placement, would be subject to mechanical vibration due to high inertial forces acting on the linkages and other components. To achieve high throughput capability, such motion induced vibration would have to be damped quickly, to reduce settling time of the platform position and orientation. This paper develops a two-time scale dynamic model of a three-degree-of-freedom planar parallel manipulator with structurally flexible linkages. Based on the two-time scale model, a composite controller, consisting of a computed torque controller for the slow time-scale or rigid body subsystem dynamics, and a linear-quadratic state-feedback regulator for the fast time-scale flexible dynamic subsystem, is designed. Simulation results show that the composite control scheme permits the parallel manipulator platform to follow a given desired trajectory, while damping structural vibration arising due to excitation from inertial forces.

Sign in / Sign up

Export Citation Format

Share Document