Study On Constraints And Their Visualization In Die CAD System

For manufacturing businesses,to improve product quality,reduce production costs,and shorten development cycle are the keys to survival and success,and the goals of eternal pursuit. Under the circumstances,the product development philosophy and the development model integrating design as well as manufacturing of constraint-based CAD design have emerged as research hotspots in recent years.As with other engineering design,die design is,by its nature,a constraint satisfaction problem,how to tailor design space in accordance with constraints. Design process is to pursue the final design object,given specified functions,structures and other constraints. It's a process interweaving trials,selections,repetitions,improvements and perfections.On the standpoint of constraint design,this thesis first classifies die design constraints according to their features. Based on the classification,and without losing general engineering sense,the thesis then proposes a die constraint information representation model,which uses templates as media and combines multiple knowledge representation methods,e.g. predicates,formulas,productions. On the basis of this model,the thesis. further treats topics in constraint design process,such as constraint interpretation design,constraint modification,constraint control,etc. Allowing for the hierarchical nature of design constraints,we bring forth a hierarchy visualization model of die constraint information. And as the outcome of research efforts,a prototype system of constraint visualization design,CVDS,is implemented.