Multiple-Mode Input Shaping Sequences for Reducing Residual Vibrations

1994 ◽  
Author(s):  
B. Whitney Rappole ◽  
Neil C. Singer ◽  
Warren P. Seering
Keyword(s):  
Closed Form ◽  
Management System ◽  
Flexible Structures ◽  
Silicon Wafers ◽  
New Method ◽  
Input Shaping ◽  
Feed Forward ◽  
Multiple Mode ◽  
Modes Of Vibration

Abstract A closed-form method of calculating Input Shaping sequences for two modes of vibration is presented. The new method eliminates the optimization routines previously required to find the same solutions. Input Shaping is a feed forward method of reducing residual vibrations in flexible structures by convolving an Input Shaping sequence with a command profile. The two-mode sequences are installed on a four-axis robot used in the manufacture of silicon wafers — the Cassette Management System. The new sequences are found to significantly improve the performance of the system. In standard throughput tests, speed increases of 15%–25% were obtained on each axis while vibrations were simultaneously reduced by 20%–90%.

A new closed-form kinematics of the generalized 3-DOF spherical parallel manipulator

Robotica ◽  
1999 ◽  
Vol 17 (5) ◽  
pp. 475-485 ◽  
Author(s):  
Zhen Huang ◽  
Y. Lawrence Yao
Keyword(s):  
Closed Form ◽  
Analytical Method ◽  
Parallel Manipulator ◽  
Degree Of Freedom ◽  
New Method ◽  
Numerical Example ◽  
Three Degree Of Freedom ◽  
Spherical Parallel Manipulator

This paper presents a new method to analyze the closed-form kinematics of a generalized three-degree-of-a-freedom spherical parallel manipulator. Using this analytical method, concise and uniform solutions are achieved. Two special forms of the three-degree-of-freedom spherical parallel manipulator, i.e. right-angle type and a decoupled type, are also studied and their unique and interesting properties are investigated, followed by a numerical example.

Modeling and Active Vibration Control for Bridge Tower Structures Under Construction

1997 ◽  
Author(s):  
Kazuto Seto ◽  
Fumio Doi ◽  
Mingzhang Ren
Keyword(s):  
Robust Control ◽  
Control Theory ◽  
Active Vibration Control ◽  
Flexible Structures ◽  
Suboptimal Control ◽  
Lumped Mass ◽  
Modes Of Vibration ◽  
Active Vibration ◽  
Under Construction ◽  
Bridge Tower

Abstract For controlling multi-modes of vibration of flexible bridge towers under construction, a lumped mass modeling method and a new method of simple robust control are proposed. Although the robust control theory such as H∞ theory is useful for controlling systems with unknown factors and variable parameters, it is not effective to control multi-modes of vibration of flexible structures. This proposed methods are specified by combining the suboptimal control theory for reducing sensor number and filtering technique for preventing spillover of neglected high modes of vibration. Effectiveness of the method is demonstrated by showing that the first five modes of vibration of a model structure of flexible bridge tower are well controlled without spillover of neglected high modes.

A new method for rapid measurement of orientations and sizes of grains in multicrystalline silicon wafers

2011 ◽  
Author(s):  
Bhushan Sopori ◽  
Debraj Guhabiswas ◽  
Przemyslaw Rupnowski ◽  
Sudhakar Shet ◽  
Srinivas Devayajanam ◽  
...  
Keyword(s):  
Silicon Wafers ◽  
New Method ◽  
Multicrystalline Silicon ◽  
Rapid Measurement

On Frequency-Domain and Time-Domain Input Shaping for Multi-Mode Flexible Structures

2003 ◽  
Vol 125 (3) ◽  
pp. 494-497 ◽  
Author(s):  
Lucy Y. Pao ◽  
Craig F. Cutforth
Keyword(s):  
Frequency Domain ◽  
Time Domain ◽  
Flexible Structures ◽  
Design Methods ◽  
Input Shaping ◽  
Residual Vibration ◽  
Know How ◽  
Frequency Domain Methods ◽  
Multi Mode

The technique of input shaping has been successfully applied to the problem of maneuvering flexible structures without excessive residual vibration. Because a shaper is designed such that vibration is eliminated at the end of the shaped input, a short shaper length means that vibration is eliminated sooner. As different shaper design methods yield different shapers, it is advantageous to know how the shaper lengths of these different methods compare. In this paper we draw comparisons between time-domain input shaping methods and frequency-domain input shaping methods after outlining conditions when non-negative amplitude shapers exist when using frequency-domain methods.

scholarly journals Design and Application of Information Management System Based on ASP.NET

2012 ◽  
Vol 6-7 ◽  
pp. 948-951 ◽  
Author(s):  
Guang Zhao ◽  
Hong Yuan Huang
Keyword(s):  
Information Management ◽  
Staff Training ◽  
Management System ◽  
Office Automation ◽  
Information Management System ◽  
New Method ◽  
Work Efficiency ◽  
Design Project ◽  
Design And Application

With ASP.NET and ADO.NET technologies the staff training information management system was developed, realize the network office automation, make the information management betimes, and improve the work efficiency. The function peculiarity and design project of the system were discussed deeply, and put forward a new method of ASP.NET application.

Adaptive input shaping for manoeuvring flexible structures using an algebraic identification technique

Automatica ◽  
2009 ◽  
Vol 45 (4) ◽  
pp. 1046-1051 ◽  
Author(s):  
E. Pereira ◽  
J.R. Trapero ◽  
I.M. Díaz ◽  
V. Feliu
Keyword(s):  
Flexible Structures ◽  
Input Shaping ◽  
Identification Technique

Closed-Loop Input Shaping for Flexible Structures Using Time-Delay Control1

1999 ◽  
Vol 122 (3) ◽  
pp. 454-460 ◽  
Author(s):  
Vikram Kapila ◽  
Anthony Tzes ◽  
Qiguo Yan
Keyword(s):  
Time Delay ◽  
Closed Loop ◽  
Flexible Structures ◽  
System Stability ◽  
Structural Vibration ◽  
Delay Systems ◽  
Linear Matrix ◽  
Input Shaping ◽  
Closed Loop Control ◽  
Loop Control

Input shaping techniques reduce the residual vibration in flexible structures by convolving the command input with a sequence of impulses. The exact cancellation of the residual structural vibration via input shaping is dependent on the amplitudes and instances of impulse application. A majority of the current input shaping schemes are inherently open-loop where impulse application at inaccurate instances can lead to system performance degradation. In this paper, we develop a closed-loop control design framework for input shaped systems. This framework is based on the realization that the dynamics of input shaped systems give rise to time delays in the input. Thus, we exploit the feedback control theory of time delay systems for the closed-loop control of input shaped flexible structures. A Riccati equation-based and a linear matrix inequality-based frameworks are developed for the stabilization of systems with uncertain, multiple input delays. Next, the aforementioned framework is applied to two input shaped flexible structure systems. This framework guarantees closed-loop system stability and performance when the impulse train is applied at inaccurate instances. Two illustrative numerical examples demonstrate the efficacy of the proposed closed-loop input shaping controller. [S0022-0434(00)00103-9]

Nonlinear Hydrodynamic Forces on Flexible Structures: A Combined-Force Model

2004 ◽  
Vol 126 (1) ◽  
pp. 78-83 ◽  
Author(s):  
Iftekhar Anam ◽  
Jose M. Roesset
Keyword(s):  
Flexible Structures ◽  
Nonlinear Problems ◽  
Nonlinear Effects ◽  
Diffraction Theory ◽  
Computational Effort ◽  
New Method ◽  
Force Model ◽  
Order Difference ◽  
The Individual ◽  
Better Than

A new combined-force method is suggested to approximate the second-order difference frequency forces from diffraction theory (Φ2 theory) with less computational effort. The new method is formulated by combining two limiting cases of the Φ2 theory; i.e., Newman’s approximation and the slender Φ2 theory. Numerical results show that the new method reproduces the individual nonlinear effects of the Φ2 theory better than the existing approximations. Results of this work also show the limitations of Morison’s equation as the slender-body counterpart of the diffraction theory for nonlinear problems.

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