Summary: | 碩士 === 國立臺北科技大學 === 製造科技研究所 === 105 === The path synthesis for a spatial curve generated by a mechanism has been done by combining three plane mechanisms which are synthesized via the projected plane curves on three perpendicular planes. The synthesized mechanism, however, usually requires more than two independent inputs and controls as well. Therefore, it requires complicated calculations to obtain the required inputs. Such complicated calculations might be too difficult and trouble for a designer. There has another method to synthesizing a spatial path by combining two plane mechanisms which are synthesized via the projected plane curves on two perpendicular planes. It requires the tracing points of two mechanisms be the same at any instant. It is, however, not easy to apply this synthesis method. Therefore, this study presents a modified method to synthesize a spatial curve by two perpendicular plane mechanisms. Although the accuracy is not so good, it is easy to apply.
The method presented in this thesis is to synthesize a mechanism firstly for the complex planar curve among the two projected curves in two perpendicular planes, then synthesize a surface cam for the other curve. Applying the characteristics of surface cam, it can modify the surface cam according to the error caused by the mechanism obtained by combing the two plane mechanisms. Therefore, the tracing points of two mechanisms will be the same at any instant. Several spatial curves are taken as examples to illustrate how to synthesize a mechanism to generate an approximate spatial path by the design method and procedure presented by this study. A practical example from a patented design is also used as an example to illustrate the method and confirm its feasibility.
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