Frequency-Modulation Input Shaping Control of Double-Pendulum Overhead Cranes

2013 ◽  
Vol 136 (2) ◽  
Author(s):  
Ziyad N. Masoud ◽  
Khaled A. Alhazza
Keyword(s):  
Frequency Modulation ◽  
Closed Loop ◽  
Single Mode ◽  
Mode Frequency ◽  
Input Shaping ◽  
Double Pendulum ◽  
Overhead Crane ◽  
Primary Input ◽  
Shaping Technique ◽  
Input Shaper

Traditionally, multimode input shaping controllers are tuned to systems' frequencies. This work suggests an alternative approach. A frequency-modulation (FM) input shaping technique is developed to tune the resonant frequencies of a system to a set of frequencies that can be eliminated by a single-mode primary input shaper. Most of the current input shaping techniques can be used as primary input shapers for the FM input shaping technique. Virtual feedback is used to modulate the closed-loop frequencies of a simulated double-pendulum model of an overhead crane to the point where the closed-loop second mode frequency becomes an odd-multiple of the closed-loop first mode frequency, which is the necessary condition for a satisfactory performance of most single-mode input shapers. The primary input shaper is based on the first mode frequency of the closed-loop system model. The input commands to the plant of the virtual feedback system are then used to drive the physical double-pendulum. Simulations results, using primary zero-vibration (ZV) and zero-vibration-derivative (ZVD) input shapers, are presented. The performance is validated experimentally on a scaled model of a double-pendulum overhead crane.

Command-Shaping Control System for Double-Pendulum Gantry Cranes

2011 ◽  
Author(s):  
Ziyad N. Masoud ◽  
Khaled A. Alhazza
Keyword(s):  
Closed Loop ◽  
Single Mode ◽  
Feedback System ◽  
Mode Frequency ◽  
Gantry Crane ◽  
Necessary Condition ◽  
Double Pendulum ◽  
Double Step ◽  
Scaled Model ◽  
Command Shaping

Traditionally, multi-mode command-shaping controllers are tuned to the system frequencies. This work suggests an opposite approach. A frequency-modulation (FM) strategy is developed to tune the system frequencies to match the frequencies eliminated by a single-mode command-shaper. The shaper developed in this work is based on a double-step command-shaping strategy. Using the FM Shaper, a simulated feedback system is used to modulate the closed-loop frequencies of a simulated double-pendulum model to the point where the closed-loop second mode frequency becomes an odd multiple of the closed-loop first mode frequency, which is the necessary condition for a satisfactory performance of a single-mode command-shaper. The double-step command-shaper is based on the closed-loop first mode frequency. The input commands to the plant of the simulated closed-loop system are then used to drive the actual double-pendulum. Performance is validated experimentally on a scaled model of a double-pendulum gantry crane.

Input Shaping Control of Double-Pendulum Bridge Crane Oscillations

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
William Singhose ◽  
Dooroo Kim ◽  
Michael Kenison
Keyword(s):  
Single Mode ◽  
Input Shaping ◽  
Double Pendulum ◽  
Bridge Crane ◽  
Efficient Operation ◽  
Input Shaper ◽  
Large Amplitude Oscillation ◽  
Control Research ◽  
Pendulum Dynamics ◽  
Input Shaping Control

Large amplitude oscillation of crane payloads is detrimental to safe and efficient operation. Under certain conditions, the problem is compounded when the payload creates a double-pendulum effect. Most crane control research to date has focused on single-pendulum dynamics. Several researchers have shown that single-mode oscillations can be greatly reduced by properly shaping the inputs to the crane motors. This paper builds on those previous developments to create a method for suppressing double-pendulum payload oscillations. The input shaping controller is designed to have robustness to changes in the two operating frequencies. Experiments performed on a portable bridge crane are used to verify the effectiveness of this method and the robustness of the input shaper.

A Frequency-Modulation Command-Shaping Strategy for Multi-Mode Systems

2013 ◽  
Author(s):  
Ziyad N. Masoud ◽  
Khaled A. Alhazza
Keyword(s):  
Frequency Modulation ◽  
Closed Loop ◽  
Single Mode ◽  
Mode Frequency ◽  
Loop System ◽  
Loop Model ◽  
Closed Loop System ◽  
Command Shaping ◽  
Scaled Models ◽  
Multi Mode

Single-mode shaped commands can be implemented for oscillations control of multi-mode systems provided that all frequencies of the system are odd-multiples of the shaped command frequency. This criterion is utilized in this work to develop a command shaping strategy for multi-mode systems. A frequency-modulation command shaper is derived based on the use of a single-mode command-shaping technique. The proposed strategy is based on deriving a closed-loop model of a multi-mode system with its modal frequencies modulated so that higher mode frequencies are odd-multiples of the first mode frequency. A single-mode double-step primary command-shaper with a design frequency equal to the first mode frequency of the closed-loop system is then used. The input command to the plant of the closed-loop system is used as shaped commands for the multi-mode system. Numerical simulations are used to demonstrate the performance of the proposed strategy along with experiments on scaled models of a triple, quadruple, and quintuple-pendulums.

Multimode Input Shaping Control of Flexible Structures Using Frequency Modulation

2016 ◽  
Author(s):  
Ziyad N. Masoud ◽  
Khaled A. Alhazza ◽  
Mohammad A. Nazzal
Keyword(s):  
Frequency Modulation ◽  
Flexible Structures ◽  
Single Mode ◽  
Feedback System ◽  
Input Shaping ◽  
Flexible Beam ◽  
Robotic Arms ◽  
Model Based ◽  
Energy Consuming ◽  
Input Shaping Control

Bulky rigid robotic arms require significantly large energy-consuming actuators. Lighter flexible robotic manipulators have many advantages over rigid manipulators in terms of cost, energy consumption, and speed. However, their structural flexibility compromises operation precision. This paper presents a multimode frequency-modulation input shaping control strategy for a flexible hanging beam performing rest-to-rest maneuvers. Frequency-modulation input shaping is used to produce shaped acceleration commands to the beam support. Model-based feedback is used to modulate the frequencies of the beam so that all higher mode frequencies become odd-integer multiples of the fundamental frequency of the feedback system. Single-mode input shaping techniques are implemented to eliminate vibrations in all modes of the model-based feedback system, and hence, the flexible beam. Numerical simulations are used to demonstrate the performance effectiveness of the proposed strategy.

A Smooth Multimode Waveform Command Shaping Considering the Effect of Hoisting

2016 ◽  
Author(s):  
Khaled A. Alhazza
Keyword(s):  
Equations Of Motion ◽  
Optimization Technique ◽  
Large Body ◽  
Single Mode ◽  
Input Shaping ◽  
Double Pendulum ◽  
Scaled Model ◽  
Command Shaping ◽  
Varying Coefficients ◽  
Time Varying Coefficients

Input shaping and command shaping control techniques are the subject of large body of research in the past several decades. Most of the research is dedicated to time invariant single-mode systems. For a double pendulum hoisting system, hoisting results in a complex system of equations of motion. For rest-to-rest maneuvers, it is a common practice in research to split maneuvers into three consecutive independent stages; hoisting up the payload from an initial position, moving it horizontally, and finally lowering it to a final location. Input shaping is used is the horizontal travel motion stage to eliminate inertia excited vibrations. Although, this approach is effective, significant time penalties are involved due to the split motion approach. Further, traditional input shaping techniques involve significant jerks in the motion commands. To overcome these drawbacks, a new smooth waveform command shaping technique is proposed to enable concurrent hoisting and travel actions. The equations of motion including time varying coefficients are derived and used to determine the coefficients of an optimum waveform shaped command profile. Genetic algorithm optimization technique is used to find the optimal values of the command parameters. The initial values of these parameters are determined assuming a constant cable length. The effectiveness of the shaped command is demonstrated through numerical simulations and experiments on a scaled model of double pendulum using different maneuvers involving simultaneous travel and linear hoisting.

Closed-Loop Input Shaping Control of Vibration in Flexible Structures via Adaptive Sliding Mode Control

2012 ◽  
Vol 19 (2) ◽  
pp. 221-233 ◽  
Author(s):  
Ming-Chang Pai
Keyword(s):  
Closed Loop ◽  
Sliding Mode ◽  
Flexible Structures ◽  
Adaptive Sliding Mode Control ◽  
Input Shaping ◽  
Parameter Uncertainties ◽  
Residual Vibration ◽  
Shaping Technique ◽  
Control Scheme ◽  
Input Shaping Control

Input shaping technique is widely used in reducing or eliminating residual vibration of flexible structures. The exact elimination of the residual vibration via input shaping technique depends on the amplitudes and instants of impulse application. However, systems always have parameter uncertainties which can lead to performance degradation. In this paper, a closed-loop input shaping control scheme is developed for uncertain flexible structures. The algorithm is based on input shaping control and adaptive sliding mode control. The proposed scheme does not need a priori knowledge of upper bounds on the norm of the uncertainties, but estimates them by using the adaptation technique. This scheme guarantees closed-loop system stability, and yields good performance and robustness in the presence of parameter uncertainties and external disturbances as well. Furthermore, it is shown that increasing the robustness to parameter uncertainties does not lengthen the duration of the impulse sequence. Simulation results demonstrate the efficacy of the proposed closed-loop input shaping control scheme.

Comparison of Input Shaping Techniques for Sway Suppression in a Double-Pendulum-Type Overhead Crane

2009 ◽  
Author(s):  
Mohd Ashraf Ahmad ◽  
Raja Mohd Taufika Raja Ismail ◽  
Mohd Syakirin Ramli ◽  
Ahmad Nor Kasruddin Nasir ◽  
Normaniha Abd Ghani ◽  
...  
Keyword(s):  
Input Shaping ◽  
Double Pendulum ◽  
Overhead Crane

Vibration reduction in flexible systems using a time-varying impulse sequence

Robotica ◽  
1995 ◽  
Vol 13 (3) ◽  
pp. 305-313 ◽  
Author(s):  
Jung-Keun Cho ◽  
Youn-Sik Park
Keyword(s):  
Vibration Suppression ◽  
Linear Time ◽  
Robot Manipulator ◽  
Input Shaping ◽  
Time Varying ◽  
Vibrational Modes ◽  
Flexible Systems ◽  
Overhead Crane ◽  
Shaping Technique ◽  
Time Varying Systems

SummaryAn input shaping technique using a time-varying impulse sequence is presented to reduce the motion-induced vibration of flexible systems in a feedforward way.The decoupled modal responses for a general linear time-varying system are firstly approximated. Upon this approximation, the time-varying impulse sequences to suppress the vibrational modes are found. The reference inputs to the systems are shaped by convolving with the time-varying impulse sequence to suppress the multimode vibrations. This technique can be also applied to suppress the vibration of nonlinear time-varying systems.The performance of this method is demonstrated with two practical examples: a moving overhead crane and a two-link robot manipulator. Consequently, this study provides an input shaping technique applicable to the vibration suppression of broader classes of flexible systems.

scholarly journals An Adjustable Zero Vibration Input Shaping Control Scheme for Overhead Crane Systems

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Abdullah Mohammed ◽  
Khalid Alghanim ◽  
Masood Taheri Andani
Keyword(s):  
Sensitivity Analysis ◽  
Control System ◽  
System Performance ◽  
Input Shaping ◽  
Overhead Crane ◽  
Shaping Technique ◽  
Design Flexibility ◽  
Control Scheme ◽  
Point To Point ◽  
Input Shaping Control

This article presents a modified zero vibration (ZV) input shaping technique to address the sensitivity and flexibility limitations of the classic ZV shapers commonly implemented in overhead crane applications. Starting with the classical ZV formulation, new parameters are introduced to optimize the control system performance according to a versatile objective function. The new shaper enhances the design flexibility and operational domain of the shaper, while it inherits the robustness properties and computational efficiency of the ZV scheme. Unlike the original ZV shaper, the proposed shaper allows for the point-to-point maneuver time to be fixed. The sensitivity analysis of the controller confirms that the new shaper effectively reduces the ZV sensitivity to the cable length variations.

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