Cylindrical Section with Helically Arranged Perforations Inspired by Nature

Inspired by the shape and helical pattern of perforations on Cholla skeleton, structural responses of cylindrical sections with multiple perforations have been studied. The common approach to define a helix however, has not been adopted to define the helix lines on the cylindrical sections. This paper proposed a systematic approach to be followed by researchers, for the generation of perforations in multiple helices pattern on surface of cylindrical section. Independent parameters were identified to offer the designers’ ability in taking control when making decision on the desired pattern of perforation along the generated helices covering the surface of the cylindrical section. Rules were imposed to standardize the process and to avoid duplications of similar models under different parameter combinations. Models with perforations along a single helix line were recommended to be generated for consideration prior to those with multiple helices. In this way, understanding the effect of factors found in single helix model can be obtained prior to the examination of the effects of much more complex factors in multiple helices.

Parameterized Model of Double-Roller Hourglass Worm Based on Pro/E Secondary Development Technology

According to the spatial meshing theory, the relative coordinate systems of non-backlash double-roller enveloping hourglass worm is established, the helix line and tooth surface equation are deduced. According to worm helix line equation, generating model with Pro/E, parametric modeling by Pro/Toolkit which is the secondary development tool belongs to Pro/E, programming relevant software.