The displacement, velocity and acceleration analysis of the general spatial 7R mechanism is discussed in this paper, fused on the method proposed in Ref. [2], an input-output algebra equation of the 16th degree in the...The displacement, velocity and acceleration analysis of the general spatial 7R mechanism is discussed in this paper, fused on the method proposed in Ref. [2], an input-output algebra equation of the 16th degree in the tan-half-angle of the output angular displacement is derived. The derivation process and computation are considerably simple. A program written in Allanguage is used to derive the coefficients of displacement equations: therefore the amount of manual work is greatly decreased. The results are verified by a numerical example. The researches of this paper and Ref. [5]found a base for establishing an expert system of spatial mechanism analysis in the future.展开更多
The spatial RSSR crank rocker mechanism is widely used in industry, but, the manufac-turing, mounting and lubrication of S pair are more complicate than R or C pair. This paperdeals with the replacement of S pair by c...The spatial RSSR crank rocker mechanism is widely used in industry, but, the manufac-turing, mounting and lubrication of S pair are more complicate than R or C pair. This paperdeals with the replacement of S pair by cress-head pair and investigates the equivalence of thetwo mechanisms with output angular displacement and oscillating angle ψ, as the object func-tion. The synthesis in terms of velocity ratio K and ψ and the influence of the cross-headstructure on the replacement have also been discussed.展开更多
Performance analysis and kinematic design of the 3-PUU pure translational parallel mechanism with vertical guide-ways are investigated. Two novel performance indices, the critical slider stroke and the main section ar...Performance analysis and kinematic design of the 3-PUU pure translational parallel mechanism with vertical guide-ways are investigated. Two novel performance indices, the critical slider stroke and the main section area of workspace, are defined; The expressions of two other indices, i.e. the global dexterity and global force transfer ratio are revised based on the main section of workspace. Using these indices, performance changes versus the varieties of dimensional parameters of mechanism are investigated in detail and the graphic descriptions of change tendencies of the performance indices are illustrated. By means of these obtained graphic descriptions, kinematic parameters for the 3-PUU pure translational parallel mechanism with better characteristics can be directly acquired.展开更多
文摘The displacement, velocity and acceleration analysis of the general spatial 7R mechanism is discussed in this paper, fused on the method proposed in Ref. [2], an input-output algebra equation of the 16th degree in the tan-half-angle of the output angular displacement is derived. The derivation process and computation are considerably simple. A program written in Allanguage is used to derive the coefficients of displacement equations: therefore the amount of manual work is greatly decreased. The results are verified by a numerical example. The researches of this paper and Ref. [5]found a base for establishing an expert system of spatial mechanism analysis in the future.
文摘The spatial RSSR crank rocker mechanism is widely used in industry, but, the manufac-turing, mounting and lubrication of S pair are more complicate than R or C pair. This paperdeals with the replacement of S pair by cress-head pair and investigates the equivalence of thetwo mechanisms with output angular displacement and oscillating angle ψ, as the object func-tion. The synthesis in terms of velocity ratio K and ψ and the influence of the cross-headstructure on the replacement have also been discussed.
基金This project is supported by National Natural Science Foundation of China (No.60275031)Municipal Key Lab Open Fund of Beijing, China (No.KP01-072200384).
文摘Performance analysis and kinematic design of the 3-PUU pure translational parallel mechanism with vertical guide-ways are investigated. Two novel performance indices, the critical slider stroke and the main section area of workspace, are defined; The expressions of two other indices, i.e. the global dexterity and global force transfer ratio are revised based on the main section of workspace. Using these indices, performance changes versus the varieties of dimensional parameters of mechanism are investigated in detail and the graphic descriptions of change tendencies of the performance indices are illustrated. By means of these obtained graphic descriptions, kinematic parameters for the 3-PUU pure translational parallel mechanism with better characteristics can be directly acquired.