Dynamic deformation analysis of a spot welding robot under high speed and heavy load working condition

2013 ◽  
Author(s):  
Yifeng Song ◽  
Hongguang Wang ◽  
Wenbin Gao ◽  
Haitao Luo
Keyword(s):  
Spot Welding ◽  
High Speed ◽  
Working Condition ◽  
Dynamic Deformation ◽  
Deformation Analysis ◽  
Welding Robot ◽  
Heavy Load

Multi-Objective Topological Optimization of Support Frame for High-Speed and Heavy-Load Triangle Track Wheel Based on Analytic Hierarchy Process

2018 ◽  
Author(s):  
Fenghe Wu ◽  
Zhaohua Wang ◽  
Yinxu Sun ◽  
Yulin Yang ◽  
Yongxin Li ◽  
...  
Keyword(s):  
Topology Optimization ◽  
High Speed ◽  
Working Condition ◽  
Average Frequency ◽  
Frequency Method ◽  
Analytic Hierarchy ◽  
Heavy Load ◽  
Multi Objective ◽  
Support Frame ◽  
Hierarchy Process

The high-speed, heavy-load and changeable triangle track wheel is a motion device that can carry out interchange between the track wheel and tire in an ordinary vehicle. The topology optimization for the support frame can reduce weight and improve the maneuverability of the vehicle. However, it is difficult to consider simultaneously its weight, stiffness and modal in the process of the structure optimization. Thus, a topology optimization method for multi-objective and multi-working-condition is proposed based on the AHP (analytic hierarchy process) and average frequency method. Firstly, considering the static multi-stiffness target and dynamic vibration frequency target, using the compromise programming method and average frequency method, the objective function of the multi-objective and multi-working-condition topology optimization is established. Then, based on the optimization target, design criteria and indexes, the lightweight hierarchical structure model of the support frame consisting of three levels and eight weight factors is established. Values of 8 weight coefficients of the multi-objective topology optimization are determined through solving the weight factor judgment matrix. Finally, considering the multi-working-condition, taking the minimum objective function of the static and dynamic characteristics as target, and the volume ratio is 50% as boundary, the mathematical model of the topology optimization is established. Simulation results show that the stiffness and strength of the support frame are improved respectively by 74.3% and 1.3% while its weight is reduced by 16.3%. This method also provides a new way to the lightweight design for other large, heavy and multi-condition equipment.

Regulator Experiment of Lubricating Oil Reutilization of DongFeng 4B (DF4B) Type Locomotive

2011 ◽  
Vol 396-398 ◽  
pp. 1895-1898
Author(s):  
Chong Zhuo Wang ◽  
Bao Hui Wang
Keyword(s):  
High Speed ◽  
Simulation Experiment ◽  
Working Condition ◽  
Laboratory Simulation ◽  
Lubricating Oil ◽  
Heavy Load ◽  
New Thought ◽  
Oil Resources ◽  
Long Time ◽  
Train Speed

With the increase of locomotive traction tonnage and train speed improvements, the DF4B locomotives have been in heavy load and high speed working condition for long time, while the lubricating oil dilution problem has not been solved. We have been in the research of the three-generation oil dilution of theDF4B locomotives in laboratory simulation experiment, especially in the oil addition experiments of the kinematic viscosity, and got a numerical trend graph and regression empirical formula. Through the diluted oil adjusting agent experiment, we inspected DF4B locomotives diesel engine for a period of tracking, and discovered that the modified oil has little influence on locomotive riding quality, thereby providing the new thought of reusing and saving the oil resources.

Oil film shape prediction of hydrostatic thrust bearing under the condition of high speed and heavy load

2018 ◽  
Vol 70 (7) ◽  
pp. 1243-1250 ◽  
Author(s):  
Xiaodong Yu ◽  
Xu Zuo ◽  
Chao Liu ◽  
Xuhang Zheng ◽  
Hang Qu ◽  
...  
Keyword(s):  
High Speed ◽  
Radial Direction ◽  
Thrust Bearing ◽  
Working Condition ◽  
Cnc Machining ◽  
Heavy Load ◽  
Content Type ◽  
Oil Film ◽  
Hydrostatic Bearing ◽  
Shape Prediction

Purpose Hydrostatic thrust bearing is a key component of the vertical CNC machining equipment, and often results in friction failure under the working condition of high speed and heavy load. The lubricating oil film becomes thin or breaks because of high speed and heavy load and it affects the high precision and stable operation of the vertical CNC machining equipment; hence, it is an effective way of avoiding friction failure for achieving the oil film shape prediction Design/methodology/approach For the hydrostatic thrust bearing with double rectangular cavities, researchers solve the deformation of the friction pairs in hydrostatic bearing by using the computation of hydrodynamics, elasticity theory, finite element method and fluid-thermal-mechanical coupled method. The deformation includes heat deformation and elasticity deformation, the shape of gap oil film is got according to the deformation of the friction pairs in hydrostatic bearing, and gets the shape of gap oil film, and determines the influencing factors and laws of the oil film shape, and achieves the prediction of oil film shape, and ascertains the mechanism of friction failure. An experimental verification is carried out. Findings Results show that the deformation of the rotational workbench is upturned along its radial direction under the working condition of high speed and heavy load. However, the deformation of the base is downturned along its radial direction and the deformation law of the gap oil film along the radius direction is estimated; the outer diameter is close but the inner diameter is divergent wedge. Originality/value The conclusion can provide a theoretical basis for the oil film control of hydrostatic thrust bearing and improve the stability of vertical CNC machining equipment.

Spot Welding Robot Technology

2016 ◽  
Vol 85 (7) ◽  
pp. 646-651
Author(s):  
Teruki ITO
Keyword(s):  
Spot Welding ◽  
Welding Robot ◽  
Robot Technology

Numerical Modeling and Simulation Analysis of Temperature Field of Disc Brake on Trains

2011 ◽  
Vol 199-200 ◽  
pp. 1492-1495 ◽  
Author(s):  
Guo Shun Wang ◽  
Rong Fu ◽  
Liang Zhao
Keyword(s):  
Temperature Field ◽  
Temperature Gradient ◽  
High Speed ◽  
Large Scale ◽  
Working Condition ◽  
Constant Speed ◽  
Brake Disc ◽  
Disc Brake ◽  
Brake Pad ◽  
Finite Element Software

The simulation calculation on the temperature field of the disc brake system on high-speed trains under the working condition of constant speed at 50Km/h is made. A steady-state calculation model is established according to the actual geometric size of a brake disc and a brake pad, and the analog calculation and simulation on the temperature field of the brake disc and the brake pad by using the large-scale nonlinear finite element software ABAQUS are carried out. The distribution rules of the temperature field of the brake disc and the brake pad under the working condition of constant speed are made known. The surface temperature of the brake disc at friction radius is the highest, with a band distribution for temperature. There exists a temperature flex point in the direction of thickness, of which the thickness occupies 15% of that of the brake disc; due to the small volume of the brake pad, the temperature gradient of the whole brake pad is not sharp, and larger temperature gradient occurs only on the contact surface.

Development of six-DOF welding robot with machine vision

2018 ◽  
Vol 32 (34n36) ◽  
pp. 1840079
Author(s):  
Wensheng Huang ◽  
Hongli Xu
Keyword(s):  
Machine Vision ◽  
High Speed ◽  
Degrees Of Freedom ◽  
High Efficiency ◽  
Target Location ◽  
Industrial Robots ◽  
Welding Robot ◽  
Edge Pixel ◽  
Six Dof ◽  
Hardware Processing

The application of machine vision to industrial robots is a hot topic in robot research nowadays. A welding robot with machine vision had been developed, which is convenient and flexible to reach the welding point with six degrees-of-freedom (DOF) manipulator, while the singularity of its movement trail is prevented, and the stability of the mechanism had been fully guaranteed. As the precise industry camera can capture the optical feature of the workpiece to reflect in the camera’s CCD lens, the workpiece is identified and located through a visual pattern recognition algorithm based on gray scale processing, on the gradient direction of edge pixel or on geometric element so that high-speed visual acquisition, image preprocessing, feature extraction and recognition, target location are integrated and hardware processing power is improved. Another task is to plan control strategy of control system, and the upper computer software is programmed in order that multi-axis motion trajectory is optimized and servo control is accomplished. Finally, prototype was developed and validation experiments show that the welding robot has high stability, high efficiency, high precision, even if welding joints are random and workpiece contour is irregular.

scholarly journals Foundation Adaptability and Subgrade Deformation Analysis of High-Speed Railway above the Mined-Out Areas

2021 ◽  
Vol 14 (1) ◽  
pp. 170-177
Author(s):  
Shuren Wang ◽  
Kunpeng Shi ◽  
Tonghe Zhou ◽  
Youfeng Zou ◽  
Jiangchun Hu
Keyword(s):  
High Speed ◽  
Deformation Analysis ◽  
High Speed Railway

Evaluating Genetic Algorithms on Welding Sequence Optimization With Respect to Dimensional Variation and Cycle Time

2011 ◽  
Author(s):  
Johan Segeborn ◽  
Johan S. Carlson ◽  
Kristina Wa¨rmefjord ◽  
Rikard So¨derberg
Keyword(s):  
Genetic Algorithms ◽  
Significant Influence ◽  
Cycle Time ◽  
Spot Welding ◽  
Fitness Function ◽  
Welding Robot ◽  
Single Criterion ◽  
Welding Sequence ◽  
Dimensional Variation ◽  
Welding Sequences

Spot welding is the predominant joining method in car body assembly. Spot welding sequences have a significant influence on the dimensional variation of resulting assemblies and ultimately on overall product quality. It also has a significant influence on welding robot cycle time and thus ultimately on manufacturing cost. In this work we evaluate the performance of Genetic Algorithms, GAs, on multi-criteria optimization of welding sequence with respect to dimensional assembly variation and welding robot cycle time. Reference assemblies are fully modelled in 3D including detailed fixtures, welding robots and weld guns. Dimensional variation is obtained using variation simulation and part measurement data. Cycle time is obtained using automatic robot path planning. GAs are not guaranteed to find the global optimum. Besides exhaustive calculations, there is no way to determine how close to the actual optimum a GA trial has reached. Furthermore, sequence fitness evaluations constitute the absolute majority of optimization computation running time and do thus need to be kept to a minimum. Therefore, for two industrial reference assemblies we investigate the number of fitness evaluations that is required to find a sequence that is optimal or a near-optimal with respect to the fitness function. The fitness function in this work is a single criterion based on a weighted and normalized combination of dimensional variation and cycle time. Both reference assemblies involves 7 spot welds which entails 7!=5040 possible welding sequences. For both reference assemblies, dimensional variation and cycle time is exhaustively calculated for all 5040 possible sequences, determining the optimal sequence, with respect to the fitness function, for a fact. Then a GA that utilizes Random Key Encoding is applied on both cases and the performance is recorded. It is found that in searching through about 1% of the possible sequences, optimum is reached in about half of the trials and 80–90% of the trials reach the ten best sequences. Furthermore the optimum of the single criterion fitness function entails dimensional variation and cycle time fairly close to their respective optimum. In conclusion, this work indicates that genetic algorithms are highly effective in optimizing welding sequence with respect to dimensional variation and cycle time.

The Development and Application of Super-Lightweight Aggregate Pumping Concrete

2012 ◽  
Vol 152-154 ◽  
pp. 24-27
Author(s):  
Chun Gao
Keyword(s):  
Bulk Density ◽  
High Speed ◽  
Working Condition ◽  
Lightweight Aggregate ◽  
Independent Study ◽  
Lightweight Aggregate Concrete ◽  
Railway Station ◽  
High Speed Railway ◽  
Aggregate Concrete

Applied in the construction of Wuhan railway station of the Wuhan-Guangzhou high-speed railway, the super-lightweight aggregate pumping concrete has been developed by the independent study on the tackifier, the substitute of lightweight aggregate for sand and tackifier for sand. The concrete has been used for 58000m3. The dry bulk density of the lightweight aggregate concrete is controlled at 1160kg/m³. And the concrete has a good performance in the homogeneity and working condition, and is easy for pumping.

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