RESEARCH ON APPLYING WAVELET ANALYSIS

TO PATH SYNTHESIS FOR COUPLER CURVES

OF PLANAR FOUR-BAR LINKAGES

Wang Chengzhi  Ji Yuebo

(School of Mechenical Engineering，Jimei University, Xiamen 361021)

Sun Daoheng

(Department of Mechanical and Electrical Engineering, Xiamen University,    Xiamen 361005)

Abstract: Using the wavelet multi-resolution analysis, the low frequency wavelet coefficients can be used to represent the coupler curve of a mechanism and stored in the database as an atlas. A corresponding closeness or measure of the error between two curves and the model redemonstrating expected curve are created. The coefficients sets have the same characteristics as the slope angles that they are independent of their directions and the scales of curves. The atlas database can be created with lager data compressing ratio and expected mechanism can be quickly retrieved from it. Comparing the closeness with the least squares of the distance between two corresponding points on expected curve and the generated coupler curve shows that the method can arrange the curves in a good indexing order when retrieving curves from the library, and it demonstrates that the wavelet analysis can be effectively used to solve the problems of path synthesis for coupler curves.

Key words: Planar four-bar linkages  Coupler curve   Mechanism synthesis  Wavelet analysis

CLC No: TH112.1

国家自然科学基金资助项目(50275127). Received 20030520, received in revised form 20040215