Error Sensitivity Analysis for Machine Tool Based on Three-Dimensional Vector Chain

2013 ◽  
Vol 457-458 ◽  
pp. 1562-1565
Author(s):  
Qiang Huang ◽  
Chan Jun Gao
Keyword(s):  
Sensitivity Analysis ◽  
Machine Tool ◽  
Three Dimensional ◽  
Error Modeling ◽  
Dimensional Vector ◽  
Modeling And Analysis ◽  
Vector Operation ◽  
Error Sensitivity ◽  
Space Error ◽  
Error Sensitivity Analysis

Error modeling and analysis can provide some important direction to the machining precision control. According to the characteristics of topology structure on machine tool, a space error model of machine tool and detailed modeling method are presented in this paper, which are based on three-dimensional vector chain. Taking a lathe as an example, the application method of this model in error sensitivity analysis is introduced. By this model, the relationship between the relative error of workpiece-tool and each source error can be solved by ordinary vector operation, and the analysis efficiency should be enhanced greatly.

Error-sensitivity analysis of hourglass worm gearing with spherical meshing elements

2013 ◽  
Vol 70 ◽  
pp. 91-105 ◽  
Author(s):  
Houjun Chen ◽  
Zhilan Ju ◽  
Chang Qu ◽  
Xiong Cai ◽  
Yan Zhang ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Error Sensitivity ◽  
Worm Gearing ◽  
Error Sensitivity Analysis

Error Sensitivity Analysis for Optimal Calibration of Parallel Kinematic Machines

2002 ◽  
Author(s):  
Fengfeng Xi ◽  
Marcel Verner ◽  
Chris Mechefske
Keyword(s):  
Sensitivity Analysis ◽  
Error Model ◽  
Condition Numbers ◽  
Geometric Errors ◽  
Error Sensitivity ◽  
Parallel Kinematic Machines ◽  
Parallel Kinematic ◽  
Error Sensitivity Analysis ◽  
Jacobian Inverse ◽  
Optimal Calibration

In this paper, error sensitivity analysis is discussed for the purpose of optimal calibration of parallel kinematic machines (PKMs). The idea is to find a less error sensitive area in the workspace for calibration. To do so, an error model is developed that takes into consideration all the geometric errors due to imprecision in manufacturing and assembly. Based on this error model, it is shown that the error mapping from the geometric errors to the pose error of the PKM depends on the Jacobian inverse. The Jacobian inverse would introduce spurious errors that would affect the calibration results, if used without proper care. Hence, it is suggested to select the areas in the workspace with smaller condition numbers for calibration. A case study is presented to illustrate the proposed method.

Modified Jacobian-Torsor Based Error Modeling and Quantitative Sensitivity Analysis for Single Axis Assembly of Machine Tool

2017 ◽  
Author(s):  
Zhengchun Du ◽  
Jian Wu ◽  
Jianguo Yang
Keyword(s):  
Sensitivity Analysis ◽  
Machine Tool ◽  
Error Modeling ◽  
Small Displacement ◽  
Cnc Machine ◽  
Statistical Solution ◽  
Mechanical Parts ◽  
Comprehensive Method ◽  
Precision Design ◽  
Final Error

The influence of component errors on the final error is a key aspect of error modeling of CNC machine tool. Nevertheless, the mechanism by which the errors in mechanical parts accumulate to result in the component errors and then impact the final error of CNC machine, has not been identified; the identification of this mechanism is highly relevant to precision design of CNC machine. In this study, error modeling based on the Jacobian-torsor theory is founded to determine the mechanism by which fundamental errors in mechanical parts influence the comprehensive error of single-axis assembly. Firstly, the constraints of small displacement torsors (SDTs) for typical features and the statistical solution are proposed to perfect the modified Jacobian-torsor model theoretically. Next, the modified Jacobian-torsor model is applied to the error modeling of a single-axis assembly in a three-axis machine center. Furthermore, the comprehensive errors of the single-axis assembly are evaluated by Monte Carlo simulation based on the synthesized error model. The accuracy and efficiency of the modified Jacobian-torsor model are verified through a comparison between the simulation results and the measured data from a batch of similar vertical machine centers. Based on the modified Jacobian-torsor model, the application of quantitative sensitivity analysis of single-axis assembly is investigated, along with an analysis of the analysis of key error sources to the synthetical error ranges of the single-axis assembly. This model is providing a comprehensive method for the better understanding of the key error source of the machine tool and has the potential to enable error allocation and precision improvement of the assembly and the whole machine tool in future.

Error sensitivity analysis of a microassembly system with coaxial alignment function

2016 ◽  
Vol 36 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Xin Ye ◽  
Pan Liu ◽  
Zhijing Zhang ◽  
Chao Shao ◽  
Yan Li
Keyword(s):  
Sensitivity Analysis ◽  
Error Compensation ◽  
Transfer Model ◽  
Motion Error ◽  
Content Type ◽  
Error Sensitivity ◽  
Assembly Accuracy ◽  
Distribution Ranges ◽  
Error Sensitivity Analysis ◽  
Precision Motion

Purpose – The purpose of this paper is to analyze the sensitivity of the motion error parameters in microassembly process, thereby improving the assembly accuracy. The motion errors of the precision motion stages directly affect the final assembly quality after the machine visual alignment. Design/methodology/approach – This paper presents the error parameters of the in-house microassembly system with coaxial alignment function, builds the error transfer model by the multi-body system theory, analyzes the error sensitivity on the sensitive direction using the Sobol method, which was based on variance, and then gets the ones which made a great degree of influence. Before the sensitivity analyzing, parts of the error sources have been measured to obtain their distribution ranges. Findings – The results of the sensitivity analysis by the Sobol method, which was based on variance, are coincident with the theoretical analysis. Besides, the results provide a reference for the error compensation in control process, for the selection of the precision motion stages and for the installation index of the motion stages of the assembly system with coaxial alignment. Originality/value – This kind of error sensitivity analysis method is of great significance for improving the assembly accuracy after visual system positioning, and increasing efficiency from the initial motion stage selection to final error compensation for designers. It is suitable for general precision motion systems be of multi-degree of freedom, for the method of modeling, measuring and analyzing used in this paper are all universal and applicative.

Sign in / Sign up

Export Citation Format

Share Document