scholarly journals Modeling and Control of Underactuated Three-Dimensional Overhead Crane Systems

2021 ◽  
Vol 6 ◽  
pp. 80-85
Author(s):  
Magdi S. Mahmoud ◽  
Nezar M. Alyazidi ◽  
Abdalrahman M. Hassanine
Keyword(s):  
Three Dimensional ◽  
Vital Role ◽  
Overhead Crane ◽  
Modeling And Control ◽  
Recent Developments ◽  
Heavy Loads ◽  
And Control ◽  
Future Work

Overhead crane systems play a vital role in different factories to transport heavy loads. This paper provides an overview of recent developments in the modeling and control of three-dimensional overhead crane systems. It provides a categorized survey of the published work. Different control methodologies when applied to overhead crane are examined, outlined and assessed to aid for future work.

Modeling and Control of a Three-Dimensional Overhead Crane

1998 ◽  
Vol 120 (4) ◽  
pp. 471-476 ◽  
Author(s):  
Ho-Hoon Lee
Keyword(s):  
Dynamic Model ◽  
Three Dimensional ◽  
Practical Case ◽  
Overhead Crane ◽  
Modeling And Control ◽  
Control Scheme ◽  
Decoupled Control ◽  
Load Swing ◽  
And Control ◽  
Two Degree Of Freedom

In this paper, a new dynamic model of a three-dimensional overhead crane is derived based on a newly defined two-degree-of-freedom swing angle. The dynamic model describes the simultaneous traveling, traversing, and hoisting motions of the crane and the resulting load swing. For anti-swing control, this paper proposes a decoupled control scheme based on the dynamic model linearized around the stable equilibrium. The decoupled scheme guarantees not only rapid damping of load swing but also accurate control of crane position and load hoisting for the practical case of simultaneous traveling, traversing, and slow hoisting motions, which is also proven by experiments.

Decentralized Control of a Tower Crane

1999 ◽  
Author(s):  
Kiyoshi Takagi ◽  
Hidekazu Nishimura
Keyword(s):  
Decentralized Control ◽  
Three Dimensional ◽  
Reduced Order Model ◽  
Flexible Structure ◽  
Order Model ◽  
Modeling And Control ◽  
Reduced Order ◽  
Tower Crane ◽  
Three Dimensional Models ◽  
And Control

Abstract This paper deals with modeling and control of a crane mounted on a tower-like flexible structure. A fast transfer of the load causes the sway of the load rope and the vibration of the flexible structure. Our object is to control both the sway and the vibration by the inherent capability of the tower crane. This paper makes its three-dimensional models for simulation and reduced-order-model in order to design the decentralized control system. Then, we design the decentralized H∞ compensator and verify the efficiency by simulations and experiments.

Nonlinear Modeling and Control of Overhead Crane Load Sway

1988 ◽  
Vol 110 (3) ◽  
pp. 266-271 ◽  
Author(s):  
Kamal A. F. Moustafa ◽  
A. M. Ebeid
Keyword(s):  
Control System ◽  
Feedback Control ◽  
Digital Computer ◽  
Nonlinear Modeling ◽  
Overhead Crane ◽  
Nonlinear Dynamical ◽  
Modeling And Control ◽  
Control Scheme ◽  
Rate Of Decay ◽  
And Control

In this paper, we derive a nonlinear dynamical model for an overhead crane. The model takes into account simultaneous travel and transverse motions of the crane. The aim is to transport an object along a specified transport route in such a way that the swing angles are suppressed as quickly as possible. We develop an antiswing control system which adopts a feedback control to specify the crane speed at every moment. The gain matrix is chosen such that a desired rate of decay of the swing angles is obtained. The model and control scheme are simulated on a digital computer and the results prove that the feedback control works well.

scholarly journals A network-based perspective on coherent structure detection from very-sparse Lagrangian data

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Giovanni Iacobello ◽  
David E. Rival
Keyword(s):  
Coherent Structure ◽  
Measurement Techniques ◽  
Three Dimensional ◽  
Coherent Motion ◽  
Modeling And Control ◽  
Structure Detection ◽  
Spatio Temporal ◽  
Lagrangian Data ◽  
And Control ◽  
Lagrangian Flow

Coherent structure detection (CSD) is a long-lasting issue in fluid mechanics research as the presence of spatio-temporal coherent motion enables simpler ways to characterize the flow dynamics. Such reducedorder representation, in fact, has significant implications for the understanding of the dynamics of flows, as well as their modeling and control (Hussain, 1986). While the Eulerian framework has been extensively adopted for CSD, Lagrangian coherent structures have recently received increasing attention, mainly driven by advancements in Lagrangian flow measurement techniques (Haller, 2015; Hadjighasem et al., 2017). Lagrangian particle tracking (LPT), in particular, is widely used nowadays due to its ability to quantity fluid-parcel trajectories in three-dimensional volumes (Schanz et al., 2016).

scholarly journals Three-Dimensional Modeling and Control of a Tethered UAV-Buoy System

2021 ◽  
Author(s):  
Ahmad Kourani ◽  
Naseem Daher
Keyword(s):  
Control System ◽  
Three Dimensional ◽  
Vertical Motion ◽  
Robotic System ◽  
Three Dimensions ◽  
Spherical Coordinate ◽  
Nonlinear Dynamical ◽  
Modeling And Control ◽  
Three Dimensional Modeling ◽  
And Control

Abstract This work presents the nonlinear dynamical model and motion controller of a system consisting of an unmanned aerial vehicle (UAV) that is tethered to a floating buoy in the three-dimensional (3D) space. Detailed models of the UAV, buoy, and the coupled tethered system dynamics are presented in a marine environment that includes surface-water currents and oscillating gravity waves, in addition to wind gusts. This work extends the previously modeled planar (vertical) motion of this novel robotic system to allow its free motion in all three dimensions. Furthermore, a Directional Surge Velocity Control System (DSVCS) is hereby proposed to allow both the free movement of the UAV around the buoy when the cable is slack, and the manipulation of the buoy’s surge velocity when the cable is taut. Using a spherical coordinate system centered at the buoy, the control system commands the UAV to apply forces on the buoy at specific azimuth and elevation angles via the tether, which yields a more appropriate realization of the control problem as compared to the Cartesian coordinates where the traditional x- , y- , and z -coordinates do not intuitively describe the tether’s tension and orientation. The proposed robotic system and controller offer a new method of interaction and collaboration between UAVs and marine systems from a locomotion perspective. The system is validated in a virtual high-fidelity simulation environment, which was specifically developed for this purpose, while considering various settings and wave scenarios.

Site-selective C(sp3)-H Functionalizations Mediated by Hydrogen Atom Transfer Reactions via α-Amino/α-Amido Radicals

Synthesis ◽  
2021 ◽  
Author(s):  
Jaspreet Kaur ◽  
Joshua Philip Barham
Keyword(s):  
Hydrogen Atom ◽  
Three Dimensional ◽  
Hydrogen Atom Transfer ◽  
Dimensional Structure ◽  
Atom Transfer ◽  
Bond Polarity ◽  
Recent Developments ◽  
A Site ◽  
Site Selective ◽  
And Control

Amines and amides, as N-containing compounds, are ubiquitous in pharmaceutically active scaffolds, natural products, agrochemicals and peptides. Amides in nature bear key responsibility for three-dimensional structure, such as in proteins. Structural modifications to amines and amides, especially at their positions α- to N, bring about profound changes in biological activity oftentimes leading to more desirable pharmacological profiles of small molecule drugs. A number of recent developments in synthetic methodology for the functionalizations of amines and amides omit the need of directing groups or pre-functionalizations, achieving direct activation of the otherwise benign C(sp3)-H bond. Among these, hydrogen atom transfer (HAT) has proven a very powerful platform for the selective activation of amines and amides to their α-amino and α-amido radicals, which can then be employed to furnish C-C and C-X (X=heteroatom) bonds. The ability to both form these radicals and control their reactivity in a site-selective manner is of utmost importance for such chemistries to witness applications in late-stage functionalization. Therefore, this review captures contemporary HAT strategies to realize chemo- and regioselective amine and amide α-C(sp3)-H functionalization, based on bond strength, bond polarity, reversible HAT equilibria, traceless electrostatic directing auxiliaries and steric effects of in situ-generated HAT agents.

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