Kinematics and force analysis of a novel offshore crane combined compensation system

Mathematical Problems in Engineering

Chen

et al. 2021

Self Cite

In order to explore the dynamic characteristics of the telescopic sleeve antiswing device for shipboard cranes under coupling excitation, a three-dimensional dynamic model of the ship crane telescopic sleeve antiswing device is established in this study, and the accuracy of the model is verified through experiments. By dynamic analysis, the influence of sleeve extension and contraction, damper parameters, and ship excitation on the payload swing is found; meanwhile, the influence of payload swing on ship stability is discovered. At the same time, the simulation results show that the three-dimensional dynamic model can accurately simulate the swing reduction characteristics of the antiswing device. The in-plane and out-plane angles of the swing are reduced by 70% and 90%. The research results have great significance to further explore the antiswing mechanism and structural design of the mechanical antiswing device.

Section: Influence Of Sleeve Expansion and Contraction Amount On Payloadmentioning

confidence: 65%

Section: Introductionmentioning

confidence: 99%

Dynamic Modeling and Analysis of the Telescopic Sleeve Antiswing Device for Shipboard Cranes

Mathematical Problems in Engineering

Chen

et al. 2021

Self Cite

“…x P and z P can be found in equations (1) and 2; L PF can be found in equation (5). The expressions of F 2x , F 2z , F 3x , F 3z , i 2x , i 2z , i 3x and i 3z can be defined in a similar manner, no need to repeat here.…”

Section: Dynamic Modelmentioning

confidence: 99%

“…[1][2][3] However, there is no mature technology or equipment to control ship's roll, pitch and heave simultaneously until now, and this poses great challenges to offshore crane operations. 4,5 On one hand, the payload swing is inevitably induced by crane's luff or slew motion because of the crane system's underactuation. On the other hand, the ship motions are amplified by the long jib which in turn cause large swing of the payload.…”

Section: Introductionmentioning

confidence: 99%

Payload swing suppression for offshore cranes using a novel triple-tagline system: Theory and experiment

Proceedings of the Institution of Mechanical Engineers, Part M:

Ren

et al. 2019

Offshore cranes are widely used for lifting operations at sea. However, due to the ship motions and crane operations, the payload swing is unavoidable, hence putting the operators in danger. Thus, this article proposes a novel triple-tagline system which has three taglines forming a triangle structure in the space and can suppress the payload swing in arbitrary directions. The kinematic and dynamic models are built in a systematic manner, which establish the theoretical basis of position synchronization and tension setting of the taglines. Then, dynamic analysis is carried out to explore the effect of the taglines’ tension on payload swing suppression, but it is unexpected to find that the taglines cannot suppress the dynamic payload swing if they always hold the static equilibrium condition. Furthermore, inspired by the air damping phenomenon, a damp-based tagline tension setting method is proposed to guarantee the resultant force of the taglines would always keep the tendency to damp the payload swing. At last, a tension/position hybrid control strategy is presented to prevent the interference of the taglines to crane operations. The validity of the proposed method and strategy are verified by experimental results.

“…Hu et al 5 presented a parallel wave compensation system to improve the anti-pendulation capability. Wang et al 6 designed a novel offshore crane combined compensation approach named four-post combined compensation based on the three-post direct ship motion compensation. They all had good wave compensation effect, but the mechanisms are complex and not easy to repair.…”

Section: Introductionmentioning

confidence: 99%

Nonlinear differential and integral sliding mode control for wave compensation system of ship-borne manipulator

Measurement and Control

Shen

et al. 2020

Ship-borne manipulator system is extremely unstable under the complex marine environment, which seriously threatens the safety of operating equipment and operators. In this paper, the dynamics and robust control of wave compensation system for ship-borne manipulator are studied. First, based on the oil circuit variable amplitude control of ship-borne manipulator, the coupling dynamic model of valve-controlled cylinder parallel accumulator is established. Then, since traditional sliding mode needs high-order derivative of feedback angle, it is difficult to implement traditional sliding mode in real hardware system. To solve these problems, a nonlinear differential and integral sliding mode control strategy is proposed. The integral term is introduced to reduce the influence of unmodeled disturbance and parameter perturbation. The stability analysis proves that the system state can track the desired target signal, and the tracking error e( t) tends to zero. In addition, in order to weaken the phenomenon of system chattering, this paper introduces a nonlinear differential control to increase the damping coefficient of the system. The simulation and experimental results show that the control law has good dynamic performance, high control accuracy, and strong anti-disturbance ability without chattering phenomenon. It is of great significance to improve the efficiency and safety of ship-borne manipulator operation, and this paper also provides useful reference for wave compensation system of other marine equipment.