scholarly journals Dynamics modelling and analysis of a large-load swinging platform

2021 ◽  
Vol 2125 (1) ◽  
pp. 012020
Author(s):  
Meng Li ◽  
Xianguo Han ◽  
Ruihai Geng

Abstract Swing platform is widely used to simulate the motion attitude of vehicles, ships and aircraft while carrying large loads. Aiming at the excessive driving force and output power of the driving parts caused by the large load swing platform, a new swing platform which can bear the large load was established. The swing platform is equipped with four spring branch chains between the moving platform and the static platform of the 6-UPS parallel mechanism, so as to offset the gravity of the large load and the inertia force of the large load in the process of motion, and the driving force of each branch chain is reduced. In this paper, the structure of the swing platform is introduced, and the dynamics of the swing platform is modeled using the Newton-Euler dynamics equation. Finally, the driving force of each branch chain of the swing platform is obtained by simulation of the dynamics of the swing platform. The simulation results show that the swing platform with four spring branch chains can effectively reduce the driving force of each branch chain compared with the traditional 6-UPS parallel mechanism swing platform.

2012 ◽  
Vol 538-541 ◽  
pp. 479-482
Author(s):  
Xin Yu Du ◽  
Hong Wei Liu

In this paper,a kind of 3-UPU spatial parallel mechanism is introduced. Through deep analysis of the degree-of-freedom (DoF) for the platform using screw theory, the position and orientation of the moving platform is discussed. At last, the 3D virtual prototype modeling of this 3-UPU parallel mechanism based on software ADAMS is developed; the kinematics simulation and analysis are also carried out accordingly. From the simulation results, we can see that the proposed calculation of the DoFs and kinematics analysis is correct.


2010 ◽  
Vol 29-32 ◽  
pp. 738-743
Author(s):  
Wen Hua Wang ◽  
Zhi You Feng ◽  
Ting Li Yang

2UPS-RPU is a new 4-DOF parallel mechanism with serial input limb. In this paper, the inverse dynamic equation of this mechanism is formulated by Newton-Euler formation based on each limb and moving platform as the studying objects. The inverse kinematics of the mechanism is analyzed. The driving force, driving moment and the constraint moment can be obtained. Finally, a computer simulation is carried out to solve the inverse dynamics of the mechanism when the motion of moving platform is given.


2012 ◽  
Vol 184-185 ◽  
pp. 1655-1659 ◽  
Author(s):  
Ji Man Luo ◽  
Zhi Hui Xing ◽  
Yang Jiang ◽  
Xiao Tong Zhang ◽  
Yu Zhen An

The purpose of this research work is to find the relationship between the driving force (F) of 3-TPS/TP parallel robot’s moving platform and the motion of tool tip, and provide reliable basis for the robot control. The Lagrange method is adopted to establish the dynamics model, and the results of the simulation by MATLAB are given in this paper. The movement of tool tip can be described by the angle α and β rotated around X-axis and Y-axis respectively, and the displacement z in the Z direction. The simulation results show that the value of F increases with the increase of the value of z, namely when the total length of the transmission rod decreases, F will increase to overcome the resistance caused by telescoping.


2017 ◽  
Vol 41 (5) ◽  
pp. 922-935
Author(s):  
HongJun San ◽  
JunSong Lei ◽  
JiuPeng Chen ◽  
ZhengMing Xiao ◽  
JunJie Zhao

In this paper, a 3-DOF translational parallel mechanism with parallelogram linkage was studied. According to the space vector relation between the moving platform and the fixed base, the direct and inverse position solutions of this mechanism was deduced through analytical method. In addition, the error of the algorithm was analyzed, and the algorithm had turned out to be effective and to have the satisfactory computational precision. On the above basis, the workspace of this mechanism was found through graphical method, which was compared with that of finding through Monte Carlo method, and there was the feasibility for analyzing the workspace of the mechanism by graphical method. The characteristic of the mechanism was analyzed by comparing the results of two analysis methods, which provided a theoretical basis for the application of the mechanism.


2014 ◽  
Vol 945-949 ◽  
pp. 1421-1425
Author(s):  
Xiu Qing Hao

Take typical parallel mechanism 3PTT as research subject, its inverse kinematic analysis solution was gotten. Dynamic model of the mechanism was established by Newton-Euler method, and the force and torque equations were derived. Dynamic simulation of 3PTT parallel mechanism was done by using ADAMS software, and simulation results have verified the correctness of the theoretical conclusions.


Author(s):  
Alessandro Cammarata ◽  
Rosario Sinatra

This paper presents kinematic and dynamic analyses of a two-degree-of-freedom pointing parallel mechanism. The mechanism consists of a moving platform, connected to a fixed platform by two legs of type PUS (prismatic-universal-spherical). At first a simplified kinematic model of the pointing mechanism is introduced. Based on this proposed model, the dynamics equations of the system using the Natural Orthogonal Complement method are developed. Numerical examples of the inverse dynamics results are presented by numerical simulation.


2013 ◽  
Vol 579-580 ◽  
pp. 659-664
Author(s):  
Xiang Bo Ouyang ◽  
Ke Tian Li ◽  
Hong Jian Xia ◽  
Su Juan Wang ◽  
Huan Wei Zhou ◽  
...  

t presents the parallel mechanism and variable acceleration control method, which is composed of slider, connecting rod, moving platform and linear guide etc. The motion platform is supported by three connecting rods through hinging, the other end of the connecting rods are respectively hinged with two sliders. Among them two pairs of connecting rod, two sliders and the moving platform formed a symmetric structure that is the so called Parallel Mechanism. The third connecting rod is parallel to one of two connecting rods, so that the two parallel connecting rods, slide block and the moving platform formed a parallelogram structure, it makes that the moving platform is always parallel to liner guiderail in the process of movement. By controlling the two sliders moving in the way of variable acceleration, it can make the trajectory curve, speed curve and acceleration curve of the moving platform are continuous, smooth, so impact and vibration of the moving platform is limited in the operation process.


2013 ◽  
Vol 427-429 ◽  
pp. 133-136
Author(s):  
Qiang Song ◽  
Pu Zeng

The driving theory and the dynamic characteristics of small radius steering, medium radius steering and big radius steering is analyzed, and the simulation model is established under Matlab/Simulink. Then the track bulldozers steering performance of the three sheerings is simulated. The results show that, at different steering modes, the running states of the two sides driving motors are not the same, and the track driving forces of the two sides vary widely. The track driving force is great in the small radius steering model, while small in the medium and big radius steering models. The simulation results lay the foundation for dual-motor drive track bulldozers steering performance matching.


2018 ◽  
Vol 8 (7) ◽  
pp. 1104 ◽  
Author(s):  
Thanh-Phuong Nguyen ◽  
Hans Wenzel ◽  
Olaf Brox ◽  
Frank Bugge ◽  
Peter Ressel ◽  
...  

The influence of the front facet reflectivity on the spectral linewidth of high power DFB (distributed feedback) diode lasers emitting at 780 nm has been investigated theoretically and experimentally. Characterization of lasers at various front facet reflections showed substantial reduction of the linewidth. This behavior is in reasonable agreement with simulation results. A minimum linewidth of 8 kHz was achieved at an output power of 85 mW with the laser featuring a front facet reflectivity of 30%. The device with a front facet reflectivity of 5% reached the same linewidth value at an output power of 290 mW.


Author(s):  
Jian-She Gao ◽  
Ren-Cheng Zheng ◽  
Yong-Sheng Zhao

The actuating input selection is an important basic problem for the parallel mechanism. Based on the screw theory, the constraint screw can be got after locking a kinematic pair in any limb, which can be taken as actuating wrench acted on the moving platform of the parallel mechanism. The constraint screw matrix is composed of the structure constraint screws and the constraint screws of the actuating pairs. The reasonableness of input selection can be judged by the rank of the constraint matrix. The performance of the combinations of actuating inputs is evaluated by the condition numbers of the force constraint matrix and the torque constraint matrix respectively. The theory presented is validated by the simulation and the maching test.


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