Research On The Extracting Of Mechanismic Kinetic Diagram Basing On Three-dimensional CAD Model

With the progress of technology and development of society, complex machine is more and more widely applied in various fields. In order to briefly express driving principle of a complex machine product, we often have to draw mechanism motion sketch, no matter in engineer design process or course teaching relating to machine. The manual drawing of mechanism motion sketch is very difficult for many design staffs, and it requires a high workload. And machine motion sketch providing with ideal functions needs more time and energy. In order to reduce workload of the design staff, liberate them from complex machine motion sketch drawing, shorten product research and development period and accelerate product update, many studies do various research on machine motion sketch drawing. This thesis concentrates on research of extracting machine motion sketch from three-dimensional CAD model.Based on three-dimensional software SolidWorks, this thesis does in-depth research and analysis on design tree of three-dimensional assembly, meaningful messages in assembly characteristic are selectively extracted, and the messages are read and stored in database. Taking pair as unit, machine motion sketch graphic elements and graphic database are established, structure sketch graphic element drawing module is properly extracted and machine motion structure sketch is drawn through identifying and matching messages.This thesis mainly does research as follow:adds different two-dimensional structure sketch graphic elements corresponding to different three-dimensional machine product model, further perfects structure sketch graphic elements and graphic database; perfects extracting mechanism motion sketch function, namely establishing extracting three-dimensional mechanism sketch, and expression of complex machine product is more and more vivid and illustrative; three-dimensional mechanism motion sketch graphic element module corresponding to extracting three-dimensional mechanism, such as moving pair, rotating pair, multi-pair components and built-in fitting etc, are also established; gear system drive mechanism sketch expansion system matching multiple gear counter drive system is developed according to multiple gear counter drive system; the drawing of mechanism motion sketch graphic module is also normalized on former foundation.Taking three simple mechanisms as examples, this thesis extracts their mechanism motion sketch, tests feasibility and rationality of mechanism sketch extracting system from reading, identification and matching assembly messages, graphic element drawing and position rectification to identification of multi-pair component and surplus rotating pair connection. Taking speed reducer as an example, its mechanism motion sketch is expanded, and the system's function to gear system sketch expansion is tested.