Controller Design Robust to Frequency Variation in a One-Link Flexible Robot Arm

1989 ◽  
Vol 111 (1) ◽  
pp. 9-14 ◽  
Author(s):  
V. V. Korolov ◽  
Y. H. Chen
Keyword(s):  
Position Control ◽  
Controller Design ◽  
Wide Spectrum ◽  
Operating Conditions ◽  
Frequency Variation ◽  
Robot Arm ◽  
Flexible Robot ◽  
Complete Knowledge ◽  
Control Scheme ◽  
Frequency Variations

The end-point position control problem of a one-link flexible robot arm under wide spectrum of operating conditions is considered. Natural frequency variations may arise in practice and are treated as the uncertainty. A robust control scheme is designed for the manipulator for some guaranteed performances without the complete knowledge of uncertainty. The only required information of the uncertainty is its possible bound.

Robotic Instrumented Complaint Wrist

1992 ◽  
Vol 114 (1) ◽  
pp. 120-123 ◽  
Author(s):  
Yangsheng Xu ◽  
R. P. Paul
Keyword(s):  
Force Control ◽  
Position Control ◽  
Contact Forces ◽  
Displacement Sensor ◽  
Robot Arm ◽  
Sensing Mechanism ◽  
Manufacturing Operations ◽  
Positioning Errors ◽  
Control Scheme ◽  
Passive Compliance

A robotic complaint wrist which combines a passive compliance device and a displacement sensor has been developed and tested. The device provides the necessary flexibility to accommodate transitions between the position control and force control modes, and avoid large impact forces as a robot makes contact with parts, as well as correct positioning errors and allow the relaxation of tolerances in assembly and manufacturing operations. The device installed between a robot arm and end-effector is composed of two parts: a passive compliance device and a sensing mechanism. The passive compliance is provided by a rubber structure; its configuration can be arranged to yield the desired stiffness ratio along and about each axis. The sensing mechanism consists of a six-joint serial linkage with a transducer at each point. The measured deflection is used to actively control the contact forces and compensate for the positioning error during motion and contact. In this paper, the design features of two prototypes of the device are described. A systematic hybrid position/force control scheme incorporating the device is presented.

Dynamic Finite Element Analysis of the Position Control System of a Two-Link Horizontal Flexible Robot

1990 ◽  
Vol 2 (2) ◽  
pp. 83-90
Author(s):  
Hiroyuki Kojima ◽  
Keyword(s):  
Finite Element ◽  
Control System ◽  
Position Control ◽  
Velocity Curve ◽  
Element Formulation ◽  
Robot Arm ◽  
Flexible Robot ◽  
Element Analysis ◽  
Flexible Arm ◽  
Position Control System

In this paper, a finite element formulation method for a horizontal flexible robot arm with two links is first presented. In the analysis, the kinetic energy of the flexible arm is represented in brief compared with previous methods, and the matrix equation of motion in consideration of the nonlinear forces, such as the Coriolis force, is derived by the finite element method and the variational theorem. Then, the state equation of the mechatronics system consisting of the flexible arm and the position control system is obtained. Secondly, numerical simulations in the case of applying path control based on the trapezoidal velocity curve are carried out by use of the Wilson-<I>θ</I> method, and the effects of the bending rigidity and the shape of the trapezoidal velocity curve on the dynamic characteristics of the mechatronics system are demonstrated.

Experiments on the position control of a one-link flexible robot arm

1989 ◽  
Vol 5 (3) ◽  
pp. 373-377 ◽  
Author(s):  
W.-J. Wang ◽  
S.-S. Lu ◽  
C.-F. Hsu
Keyword(s):  
Position Control ◽  
Robot Arm ◽  
Flexible Robot

Controller design of a one-link flexible robot arm

1993 ◽  
Vol 49 (1) ◽  
pp. 117-126 ◽  
Author(s):  
Z. Abduljabbar ◽  
M.M. Elmadany ◽  
H.D. Al-Dokhiel
Keyword(s):  
Controller Design ◽  
Robot Arm ◽  
Flexible Robot

Tip Position Control of a Flexible Robot Arm Considering the Reduction Gear's Friction

1990 ◽  
Vol 2 (2) ◽  
pp. 91-96
Author(s):  
Yasuo Yoshida ◽  
◽  
Masato Tanaka
Keyword(s):  
Feedback Control ◽  
Dynamic Characteristics ◽  
Position Control ◽  
Viscous Friction ◽  
Open Loop ◽  
Robot Arm ◽  
Flexible Robot ◽  
Position Feedback ◽  
Linear Friction ◽  
Tip Position

The reduction gear's friction strongly affects the dynamic characteristics of a one-link flexible robot arm. Experiments of open loop response by motor torque were performed in two cases of large and small values of the reduction gear's friction, and compared with simulation. The reduction gear's friction has both viscous and Coulomb aspects and can be approximately treated as an equivalent viscous friction. However, tip position control was very difficult in the case of large friction with an equivalent viscous friction. Experiments indicated that tip position feedback control was possible by using a dither signal and linearizing the non-linear friction.

Tip Position Control of Single Flexible Links via Parallel Feedforward Compensation

2019 ◽  
Author(s):  
Keyvan Noury ◽  
Bingen Yang
Keyword(s):  
Closed Loop ◽  
Position Control ◽  
Control Method ◽  
Robot Arm ◽  
Flexible Robot ◽  
Order Process ◽  
Nonminimum Phase ◽  
Model Mismatch ◽  
Tip Position ◽  
And Performance

Abstract Developed in this work, is a simple and innovative control method, by which a nonminimum-phase (NMP) process can be easily stabilized in a closed-loop setting. The method is named as the parallel feed-forward compensation with derivative effort (PFCD). Through use of a high order process, the control system designed by the PFCD method is shown to be less influenced by noise, disturbance, and model mismatch, compared to other methods. Moreover, the necessary data required for implementing the PFCD method are discussed. The proposed control method is illustrated on tip position control in a slewing beam as a flexible robot arm, in which the effectiveness of the PFCD method is demonstrated. In addition, the proposed control method is compared with the existing methods in terms of stability and performance. The paper is concluded with notes about the advantages.

A13 Basic Research of End Point Position Control for Two Links Flexible Robot Arm

2009 ◽  
Vol 2009.11 (0) ◽  
pp. 167-170
Author(s):  
Kiyoharu NAKAGAWA ◽  
Ryouta AIKAWA ◽  
Toru WATANABE ◽  
Kazuto SETO
Keyword(s):  
Position Control ◽  
Basic Research ◽  
Robot Arm ◽  
Flexible Robot ◽  
Point Position ◽  
End Point
Sign in / Sign up

Export Citation Format

Share Document