An intriguing challenge that arises when folding beetles is a structure called the scutellum. The scutellum is a small triangular structure that bridges between the thorax and elytra (wing "covers"), making it a central part of the overall structure in a beetle design. First, the basic structure of the split between the thorax and abdomen can be achieved using a few basic pleats incorporated as wide, single unit long flaps. This it shown on the right (folded form below):
There are two large disadvantages to this structure, however (don't get me wrong, I love Dr. Lang's beetles). First, the scutellum itself is not actually folded, but simply suggested by the surrounding creases, giving the structure a receded appearance on the finished model. This is less desirable as it is not accurate to a real beetle. Keeping this in mind, I developed the CP on the right (folded form below), which remains among the most aesthetic and foldable scutellum designs I have seen, along with a few found in the works of Kota Imai (I know the folded forms look identical, but try folding them and see the difference!):
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Perhaps the most straightforward method to achieve a scutellum utilizing the above structure is to incorporate a few basic level shifters as shown below. Perhaps first seen in the works of Dr. Lang, this incorporates a wide, vertical pleat to separate the elytra and positions two of the shifting structures so they cut off the top corners of the pleat at 45 degree angles. The crease pattern is shown on the left with the folded form below. For an example of a variation of this in use, see Dr. Lang's awesome Stag Beetle.
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The above design addresses the first issue well and might be the best solution for many models. However, the second issue is efficiency. In all of the above arrangements, the pleats separating the elytra take up four units of paper width. In principle, it seems like it would be possible to achieve the same effect using half this much paper. While technically difficult to execute, this is indeed possible through use of an asymmetric arrangement. Shown on the left, this CP uses significantly less paper to create the elytra separation line while still retaining exactly the same folded appearance as the previous patterns. Note that the two horizontal pleats shown in the first CP above still comprise the only paper used. Although this design has already had much time and refinement invested, it seems likely that multiple variations are possible, with significant potential for the discovery of more elegant, foldable configurations.
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