دانلود رایگان مقاله ساخت نوسان: ساخت اسباب بازی شخصی رولی پلی

Abstract

A roly-poly toy is considered as one of the oldest toys in history. People, both young and old, are fascinated by its unique ability to right itself when pushed over. There exist different kinds of roly-poly toys with various shapes. Most of them share a similar bottom which is a hollow hemisphere with a weight inside. However, it is not an easy task to make an arbitrary model to swing like a roly-poly due to the delicate equilibrium condition between the center of mass of the roly-poly toy and the shape of the hemisphere. In this paper, we present a computer-aided method to help casual users design a personalized roly-poly toy and fabricate it through 3D printing with reduced material usage and sufficient stability. The effectiveness of our method is validated on various models. Our method provides a novel easy-to-use means to design an arbitrary roly-poly toy with an ordinary 3D printing machine, extricating amateurs from the dilemma of finding extra weight to balance the shape.

5. Conclusions and discussions

We have introduced an effective method to design personalized roly-poly toys. Our optimized toys can regain balance by themselves when they are pushed over. We also favor a well-balanced shape and a larger amplitude of swing without reducing the motion stability. The effectiveness of our method are validated by various results. (See Fig. 10.) Our method has some limitations. (1). The center of mass position of U in Phase 1 is adjusted through inner carving, which may limit the shape of the resulting toy. One solution to eliminate this limitation is to optimize the shape of U (Hu et al., 2015). (2). We use the same material for both U and L. Employing multiple materials will enable the optimization process with more degrees of freedom and produce more visually pleasing results. For example, we can use a larger density material for L and a lighter density material for U to increase the stability of the resulting toy. (3). The upper part and the base are optimized separately. It will be interesting to merge U and L first and then optimize the whole merged shape directly. We will leave it as our future work.