To improve the precisions of pose error analysis for 6-dof parallel kinematic mechanism( PKM)during assembly quality control,a Sobol sequence based on Quasi Monte Carlo( QMC) method is introduced and implemented in po...To improve the precisions of pose error analysis for 6-dof parallel kinematic mechanism( PKM)during assembly quality control,a Sobol sequence based on Quasi Monte Carlo( QMC) method is introduced and implemented in pose accuracy analysis for the PKM in this paper. The Sobol sequence based on Quasi Monte Carlo with the regularity and uniformity of samples in high dimensions,can prevail traditional Monte Carlo method with up to 98. 59% and 98. 25% enhancement for computational precision of pose error statistics.Then a PKM tolerance design system integrating this method is developed and with it pose error distributions of the PKM within a prescribed workspace are finally obtained and analyzed.展开更多
Measures of irregularity of a point set or sequence, such as discrepancy and dispersion, play a central role in quasi Monte Carlo methods. In this paper, we introduce and study a new measure of irregularity, called v...Measures of irregularity of a point set or sequence, such as discrepancy and dispersion, play a central role in quasi Monte Carlo methods. In this paper, we introduce and study a new measure of irregularity, called volume dispersion. It is a measure of deviation of point sets from the uniform distribution. We then generalize the concept of volume dispersion to more general cases as measures of representation of point sets for general probability distributions. Various relations among these measures and the traditional discrepancy and dispersion are investigated.展开更多
基金Sponsored by the National Defense Basic Scientific Research Program(Grant No.A0320110019)the Shanghai Science and Technology Innovation Action Plan(Grant No.11DZ1120800)
文摘To improve the precisions of pose error analysis for 6-dof parallel kinematic mechanism( PKM)during assembly quality control,a Sobol sequence based on Quasi Monte Carlo( QMC) method is introduced and implemented in pose accuracy analysis for the PKM in this paper. The Sobol sequence based on Quasi Monte Carlo with the regularity and uniformity of samples in high dimensions,can prevail traditional Monte Carlo method with up to 98. 59% and 98. 25% enhancement for computational precision of pose error statistics.Then a PKM tolerance design system integrating this method is developed and with it pose error distributions of the PKM within a prescribed workspace are finally obtained and analyzed.
基金the Initiating Research Fund for theReturned Personnel from the State Education Ministry ofChina!( No. 1996-664)
文摘Measures of irregularity of a point set or sequence, such as discrepancy and dispersion, play a central role in quasi Monte Carlo methods. In this paper, we introduce and study a new measure of irregularity, called volume dispersion. It is a measure of deviation of point sets from the uniform distribution. We then generalize the concept of volume dispersion to more general cases as measures of representation of point sets for general probability distributions. Various relations among these measures and the traditional discrepancy and dispersion are investigated.
