Application of Robust Control Law for Linear Slider

2008 ◽  
Vol 2 (1) ◽  
pp. 34-42 ◽  
Author(s):  
Satoshi Yamamoto ◽  
◽  
Shinji Wakui
Keyword(s):  
Robust Control ◽  
Disturbance Observer ◽  
High Speed ◽  
Control Law ◽  
Model Matching ◽  
Positioning Accuracy ◽  
Control Laws ◽  
Modified Model ◽  
Applied Model ◽  
Model Following

The most important specifications in precision positioning are positioning accuracy and settling time. When a positioning sensor based on required specifications is installed in equipment, every effort is made to realize throughput, i.e., high-speed positioning. We applied model-matching 2-degree-of-freedom (DOF) control to a linear slider to realize positioning, but found that positioning waveforms were uneven under different conditions. To overcome this problem, we applied robust control laws, e.g., MM-2DOF with a disturbance observer, robust 2DOF control, and modelfollowing 2DOF control to the linear slider. A comparative study confirmed experimentally that robust 2DOF control was most suitable. To improve modelfollowing 2DOF control, we modified model-following 2DOF control and its robust positioning.

Sensorless Force Control for High-speed Pressurization

2001 ◽  
Vol 13 (3) ◽  
pp. 222-229
Author(s):  
Shigeyasu Kawaji ◽  
◽  
Fuminori Ozaki ◽  
Ryutaro Higashi ◽  
Keyword(s):  
Force Control ◽  
Semiconductor Manufacturing ◽  
Disturbance Observer ◽  
High Speed ◽  
Position Control ◽  
Piecewise Polynomial ◽  
Speed Sensorless ◽  
Model Following ◽  
Ic Testing ◽  
Key Techniques

Force control technology needs a breakthrough to be used for practical purposes because it is rarely used in the industry although it is being improved in academic circles. We propose solving problems of conventional position control in pressurization using high-speed sensorless force control for the IC testing handler used in semiconductor manufacturing. The key techniques to solve the problem are piecewise polynomial trajectory generation to meet needs for high-speed operation, a model-following force servo to achieve pressurizing conditions, and a disturbance observer to estimate pressurization. The effectiveness of the proposed method is confirmed in experiments.

Robust High-Speed Positioning Servo System Based on Disturbance Observer

2009 ◽  
Vol 129 (3) ◽  
pp. 235-242 ◽  
Author(s):  
Masaki Sazawa ◽  
Kiyoshi Ohishi ◽  
Seiichiro Katsura
Keyword(s):  
Disturbance Observer ◽  
High Speed ◽  
Servo System

scholarly journals Sliding Mode Robust Control of a Wire-Driven Parallel Robot Based on HJI Theory and a Disturbance Observer

IEEE Access ◽  
2020 ◽  
Vol 8 ◽  
pp. 215235-215245
Author(s):  
Yuqi Wang ◽  
Qi Lin ◽  
Jiacai Huang ◽  
Lei Zhou ◽  
Jinjiang Cao ◽  
...  
Keyword(s):  
Robust Control ◽  
Disturbance Observer ◽  
Sliding Mode ◽  
Parallel Robot

Integral terminal sliding-mode robust vibration control of large space intelligent truss structures using a disturbance observer

2021 ◽  
pp. 095441002110290
Author(s):  
Dalong Tian ◽  
Jianguo Guo
Keyword(s):  
Robust Control ◽  
Forced Vibration ◽  
Disturbance Observer ◽  
Sliding Mode ◽  
External Disturbance ◽  
Truss Structures ◽  
Model Parameters ◽  
Large Space ◽  
Terminal Sliding Mode ◽  
Piezoelectric Stack Actuator

This study aims to develop an advanced integral terminal sliding-mode robust control method using a disturbance observer (DO) to suppress the forced vibration of a large space intelligent truss structure (LSITS). First, the dynamics of the electromechanical coupling of the piezoelectric stack actuator and the LSITS, based on finite element and Lagrangian methods, are established. Subsequently, to constrict the vibration of the structure, a novel integral terminal sliding-mode control (ITSMC) law for the DO is used to estimate the parameter perturbation of the LSITS based on a continuous external disturbance. Simulation results show that, under a forced vibration and compared with the ITSMC system without a DO, the displacement amplitude of the ITSMC system with the DO is effectively reduced. In the case where the model parameters of the LSITS deviate by ±50%, and an unknown continuous external disturbance exists, the control system with the DO can adequately attenuate the structural vibration and realize robust control. Concurrently, the voltage of the employed piezoelectric stack actuator is reduced, and voltage jitter is alleviated.

scholarly journals Adaptive Optimal Robust Control for Uncertain Nonlinear Systems Using Neural Network Approximation in Policy Iteration

2021 ◽  
Vol 11 (5) ◽  
pp. 2312
Author(s):  
Dengguo Xu ◽  
Qinglin Wang ◽  
Yuan Li
Keyword(s):  
Neural Network ◽  
Optimal Control ◽  
Robust Control ◽  
Nonlinear Systems ◽  
Policy Iteration ◽  
Control Law ◽  
Globally Asymptotically Stable ◽  
Control Approach ◽  
Input Uncertainties ◽  
Theoretical Results

In this study, based on the policy iteration (PI) in reinforcement learning (RL), an optimal adaptive control approach is established to solve robust control problems of nonlinear systems with internal and input uncertainties. First, the robust control is converted into solving an optimal control containing a nominal or auxiliary system with a predefined performance index. It is demonstrated that the optimal control law enables the considered system globally asymptotically stable for all admissible uncertainties. Second, based on the Bellman optimality principle, the online PI algorithms are proposed to calculate robust controllers for the matched and the mismatched uncertain systems. The approximate structure of the robust control law is obtained by approximating the optimal cost function with neural network in PI algorithms. Finally, in order to illustrate the availability of the proposed algorithm and theoretical results, some numerical examples are provided.

Robust control of high-speed synchronous reluctance machines

2015 ◽  
Author(s):  
Alessandra Guagnano ◽  
Gianluca Rizzello ◽  
Francesco Cupertino ◽  
David Naso
Keyword(s):  
Robust Control ◽  
High Speed

Industrial compliant robot bases in interaction tasks: a force tracking algorithm with coupled dynamics compensation

Robotica ◽  
2016 ◽  
Vol 35 (8) ◽  
pp. 1732-1746 ◽  
Author(s):  
Loris Roveda ◽  
Nicola Pedrocchi ◽  
Federico Vicentini ◽  
Lorenzo Molinari Tosatti
Keyword(s):  
Closed Loop ◽  
Control Law ◽  
Light Weight ◽  
Mobile Platforms ◽  
Control Laws ◽  
Assembly Task ◽  
Base Position ◽  
Force Tracking ◽  
Compliant Robot ◽  
Target Force

SUMMARYLight-weight manipulators are used in industrial tasks mounted on mobile platforms to improve flexibility. However, such mountings introduce compliance affecting the tasks. This work deals with such scenarios by designing a controller that also takes into account compliant environments. The controller allows the tracking of a target force using the estimation of the environment stiffness (EKF) and the estimation of the base position (KF), compensating the robot base deformation. The closed-loop stability has been analyzed. Observers and the control law have been validated in experiments. An assembly task is considered with a standard industrial non-actuated mobile platform. Control laws with and without base compensation are compared.

Sign in / Sign up

Export Citation Format

Share Document