Vibration and Position Control of Overhead Crane With Three-Dimensional Variable Length Cable Subject to Input Amplitude and Rate Constraints

Author(s):  
Xueyan Xing ◽  
Jinkun Liu
2018 ◽  
Vol 141 (4) ◽  
Author(s):  
Jian-Wei Ma ◽  
De-Ning Song ◽  
Zhen-Yuan Jia ◽  
Wen-Wen Jiang ◽  
Fu-Ji Wang ◽  
...  

To reduce the contouring errors in computer-numerical-control (CNC) contour-following tasks, the cross-coupling controller (CCC) is widely researched and used. However, most existing CCCs are well-designed for two-axis contouring and can hardly be generalized to compensate three-axis curved contour following errors. This paper proposes an equivalent-plane CCC scheme so that most of the two-axis CCCs or flexibly designed algorithms can be utilized for equal control of the three-axis contouring errors. An initial-value regeneration-based Newton method is first proposed to compute the foot point from the actual motion position to the desired contour with a high accuracy, so as to establish the equivalent plane where the estimated three-dimensional contouring-error vector is included. After that, the signed contouring error is computed in the equivalent plane, thus a typical two-axis proportional-integral-differential (PID)-based CCC is utilized for its control. Finally, the two-axis control commands generated by the typical CCC are coupled to three-axis control commands according to the geometry of the established equivalent plane. Experimental tests are conducted to verify the effectiveness of the presented method. The testing results illustrate that the proposed equivalent-plane CCC performs much better than conventional method in both error estimation and error control.


Author(s):  
Tsung-Chih Lin ◽  
Yu-Chen Lin ◽  
Majid Moradi Zirkohi ◽  
Hsi-Chun Huang

In this paper, a novel direct adaptive fuzzy moving sliding mode proportional integral (PI) tracking control of a three-dimensional (3D) overhead crane which is modeled by five highly nonlinear second-order ordinary differential equations is proposed. The fast and robust position regulation and antiswing control can be achieved based on the proposed approach. Due to universal approximation theorem, fuzzy control provides nonlinear controller, i.e., fuzzy logic controllers, to perform the unknown nonlinear control actions. Simultaneously, in order to achieve fast and robust regulation and to enhance robustness in the presence of disturbance and parameter variations, moving sliding mode control (SMC) is introduced to tradeoff between reaching phase and sliding phase. Hence, the sliding surface is moved by changing the magnitude of the slope by adaptive law and varying the intercept by tuning algorithm. Simulations performed using a scaled 3D mathematical model of the crane confirm that the proposed control scheme can keep the horizontal position of the payload invariable and suppress the swing of the payload effectively during the hoisting or lowing process.


Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2658
Author(s):  
Jun Morita ◽  
Takanori Goto ◽  
Shinji Kanehashi ◽  
Takeshi Shimomura

The critical phenomena of double percolation on polybutadiene (PB)/polyethylene glycol (PEG) blends loaded with poly-3-hexylthiophene (P3HT) nanofibers is investigated. P3HT nanofibers are selectively localized in the PB phase of the PB/PEG blend, as observed by scanning force microscopy (SFM). Moreover, double percolation is observed, i.e., the percolation of the PB phase in PB/PEG blends and that of the P3HT nanofibers in the PB phase. The percolation threshold (φcI) and critical exponent (tI) of the percolation of the PB phase in PB/PEG blends are estimated to be 0.57 and 1.3, respectively, indicating that the percolation exhibits two-dimensional properties. For the percolation of P3HT nanofibers in the PB phase, the percolation threshold (φcII) and critical exponent (tII) are estimated to be 0.02 and 1.7, respectively. In this case, the percolation exhibits properties in between two and three dimensions. In addition, we investigated the dimensionality with respect to the carrier transport in the P3HT nanofiber network. From the temperature dependence of the field-effect mobility estimated by field-effect transistor (FET) measurements, the carrier transport was explained by a three-dimensional variable range hopping (VRH) model.


1992 ◽  
Vol 114 (3) ◽  
pp. 366-376 ◽  
Author(s):  
M. Zhu ◽  
S. Weinbaum ◽  
D. E. Lemons

A new formulation of the combined macro and microvascular model for heat transfer in a human arm developed in Song et al. [1] is proposed using a recently developed approximate theory for the heat exchange between countercurrent vessels embedded in a tissue cylinder with surface convection [2]. The latter theory is generalized herein to treat an arm with an arbitrary variation in cross-sectional area and continuous bleed off from the axial vessels to the muscle and cutaneous tissue. The local microvascular temperature field is described by a “hybrid” model which applies the Weinbaum-Jiji [3] and Pennes [4] equations in the peripheral and deeper tissue layers, respectively. To obtain reliable end conditions at the wrist and other model input parameters, a plethysmograph-calorimeter has been used to measure the blood flow distribution between the arm and hand circulations, and hand heat loss. The predictions of the model show good agreement with measurements for the axial surface temperature distribution in the arm and confirm the minimum in the axial temperature variation first observed by Pennes [4] for an arm in a warm environment.


2001 ◽  
Vol 86 (4) ◽  
pp. 1546-1554 ◽  
Author(s):  
S. Glasauer ◽  
M. Dieterich ◽  
Th. Brandt

To find an explanation of the mechanisms of central positional nystagmus in neurological patients with posterior fossa lesions, we developed a three-dimensional (3-D) mathematical model to simulate head position-dependent changes in eye position control relative to gravity. This required a model implementation of saccadic burst generation, of the neural velocity to eye position integrator, which includes the experimentally demonstrated leakage in the torsional component, and of otolith-dependent neural control of Listing's plane. The validity of the model was first tested by simulating saccadic eye movements in different head positions. Then the model was used to simulate central positional nystagmus in off-vertical head positions. The model simulated lesions of assumed otolith inputs to the burst generator or the neural integrator, both of which resulted in different types of torsional-vertical nystagmus that only occurred during head tilt in roll plane. The model data qualitatively fit clinical observations of central positional nystagmus. Quantitative comparison with patient data were not possible, since no 3-D analyses of eye movements in various head positions have been reported in the literature on patients with positional nystagmus. The present model, prompted by an open clinical question, proposes a new hypothesis about the generation of pathological nystagmus and about neural control of Listing's plane.


2012 ◽  
Vol 198-199 ◽  
pp. 1053-1056
Author(s):  
Liang Han ◽  
Jing Song Jin ◽  
Wei Zhang

Tennis is a very elegant sport, with a strong sense of competitiveness and appreciation, which has gained more and more attentions in our country, and it tends to be a fashion. This project is to achieve the measurement of tennis batting motion attitude in three dimensional space using a combination of the three-axis MEMS(Micro-electromechanical Systems) sensors, and make research on the principle of measurement system, composition and data acquisition. Body posture measurement system is to measure the attitude measurement in human movement, it can be applied to study the movement posture or to meet the requirements of position control, which provides theoretical foundation for scientific training and prevention of sports injury and also plays a significant and instructional role in improving the training levels of tennis playing and generalizing nationwide fitness campaign.


Sign in / Sign up

Export Citation Format

Share Document