In the course of mechanical part designing, process p lanning and assembling designing, we often have to calculate and analyse a dimen sion chain. Traditionally, a dimension chain is established and calculated m anual...In the course of mechanical part designing, process p lanning and assembling designing, we often have to calculate and analyse a dimen sion chain. Traditionally, a dimension chain is established and calculated m anually. With wide computer application in the field of mechanical design and ma nufacture, people began to use a computer to acquire and calculate a dimension c hain automatically. In reported work, a dimension chain can be established and c alculated automatically. However, dimension text values of dimensions composing a dimension chain and these dimensions’ tolerance’s upper values and lower valu es are put into a computer manually, which is inefficient and easy to make mis takes. In order to overcome above difficulties. it is very important to acquir e noted dimensions automatically, furthermore analyse and calculate a dimens ion chain, then show results. At present AutoCAD softwares of Autodesk company h ave been used popularly in mechanical designing. For automatically acquiring noted dimensions, analyzing and calculating a dimension chain in a design draw in AutoCAD, this paper introduces the solvable scheme of automatic dimension acq uisition and dimension chain calculation in AutoCAD by ObjectARX. ObjectARX is a developing tool for AutoCAD. In this paper a dimension chain is expressed b y three matrixes, which respectively stand for dimension text value matrix, tole rance’s upper value matrix and tolerance’s lower value matrix. The developed p rogram can be used to both calculate a assembling dimension chain, and a process dimension chain. When the program running in AutoCAD, noted dimensions comp osing a dimension chain in AutoCAD are selected in turn with a mouse, then the c omputer begin to calculate the dimension chain and results are shown in a dialog box. A running example is given in this paper.展开更多
文摘In the course of mechanical part designing, process p lanning and assembling designing, we often have to calculate and analyse a dimen sion chain. Traditionally, a dimension chain is established and calculated m anually. With wide computer application in the field of mechanical design and ma nufacture, people began to use a computer to acquire and calculate a dimension c hain automatically. In reported work, a dimension chain can be established and c alculated automatically. However, dimension text values of dimensions composing a dimension chain and these dimensions’ tolerance’s upper values and lower valu es are put into a computer manually, which is inefficient and easy to make mis takes. In order to overcome above difficulties. it is very important to acquir e noted dimensions automatically, furthermore analyse and calculate a dimens ion chain, then show results. At present AutoCAD softwares of Autodesk company h ave been used popularly in mechanical designing. For automatically acquiring noted dimensions, analyzing and calculating a dimension chain in a design draw in AutoCAD, this paper introduces the solvable scheme of automatic dimension acq uisition and dimension chain calculation in AutoCAD by ObjectARX. ObjectARX is a developing tool for AutoCAD. In this paper a dimension chain is expressed b y three matrixes, which respectively stand for dimension text value matrix, tole rance’s upper value matrix and tolerance’s lower value matrix. The developed p rogram can be used to both calculate a assembling dimension chain, and a process dimension chain. When the program running in AutoCAD, noted dimensions comp osing a dimension chain in AutoCAD are selected in turn with a mouse, then the c omputer begin to calculate the dimension chain and results are shown in a dialog box. A running example is given in this paper.
