Curved surface generation device and curved surface generation program

Abstract

A surface generation device includes: a profile curve setting unit 2 configured to set a profile curve fitted to a part of shape data, a profile curve movement unit 3 configured to move the profile curve so as to satisfy a predetermined condition, and a surface generation unit 4 configured to generate a surface defined by a locus obtained by moving the profile curve satisfying the predetermined conditions. The predetermined conditions include a condition in which a locus of one point (for example, midpoint) on the profile curve becomes a line of curvature of the surface to be generated. Using such a condition, it is possible to efficiently obtain the high quality surface by setting the line of curvature indicating a flow of the surface as a guide line of a sweep method without repeating trial and error many times.

1 - 12 . (canceled) 
     
     
         13 . A method for generating a virtual model of a surface of a physical model, comprising:
 inputting shape data of the physical model;   setting an initial profile curve fitted to the surface of the shape data;   applying a sweep process that intermittently adjusts the initial profile curve along the surface such that a point on the profile curve as it moves through the intermittent adjustments tracks a line of curvature of the surface; and   generating surface data for virtual model of the surface from the initial profile curve and at least some intermittent adjustments of the initial profile curve.   
     
     
         14 . The method of  claim 13 , wherein the sweep process includes rotation of the profile curve. 
     
     
         15 . The method of  claim 13 , wherein the sweep process includes translation of the profile curve. 
     
     
         16 . The method of  claim 13 , wherein the generating includes generating from endpoints of at least some intermediate iterative adjustments of the profile curve. 
     
     
         17 . The method of  claim 13 , wherein the surface has a line of curvature, such that the intermittent adjustments of the profile curve collectively more closely match the line of curvature than the initial profile curve as initially fitted to the shape data. 
     
     
         18 . A non-transitory computer readable medium storing instructions for generating a virtual model of a surface of a physical model, which when executed by a processor cause the processor to perform operations comprising:
 inputting shape data of the physical model;   setting an initial profile curve fitted to the surface of the shape data;   applying a sweep process that intermittently adjusts the initial profile curve along the surface such that a point on the profile curve as it moves through the intermittent adjustments tracks a line of curvature of the surface; and   generating surface data for virtual model of the surface from the initial profile curve and at least some intermediate adjustments of the initial profile curve.   
     
     
         19 . The non-transitory computer readable medium of  claim 18 , wherein the sweep process includes rotation of the profile curve. 
     
     
         20 . The non-transitory computer readable medium of  claim 18 , wherein the sweep process includes translation of the profile curve. 
     
     
         21 . The non-transitory computer readable medium of  claim 18 , wherein the generating includes generating from endpoints of at least some intermediate iterative adjustments of the profile curve. 
     
     
         22 . The non-transitory computer readable medium of  claim 18 , wherein the surface has a line of curvature, such that the intermittent adjustments of the profile curve collectively more closely match the line of curvature than the initial profile curve as initially fitted to the shape data. 
     
     
         23 . A system, comprising:
 a processor programmed to execute instructions;   a non-transitory computer readable medium storing instructions for generating a virtual model of a surface of a physical model, which when executed by the processor cause the system to perform operations comprising:
 inputting shape data of the physical model; 
 setting an initial profile curve fitted to the surface of the shape data; 
 applying a sweep process that intermittently adjusts the initial profile curve along the surface such that a point on the profile curve as it moves through the intermittent adjustments tracks a line of curvature of the surface; and 
 generating surface data for virtual model of the surface from the initial profile curve and at least some intermediate adjustments of the initial profile curve. 
   
     
     
         24 . The system of  claim 23 , wherein the sweep process includes rotation of the profile curve. 
     
     
         25 . The system of  claim 23 , wherein the sweep process includes translation of the profile curve. 
     
     
         26 . The system of  claim 23 , wherein the generating includes generating from endpoints of at least some intermediate iterative adjustments of the profile curve. 
     
     
         27 . The system of  claim 23 , wherein the surface has a line of curvature, such that the intermittent adjustments of the profile curve collectively more closely match the line of curvature than the initial profile curve as initially fitted to the shape data. 
     
     
         28 . A method for generating a virtual model of a surface of a physical model, comprising:
 inputting shape data of the physical model;   setting a profile curve C( 0 ) fitted to the surface of the shape data, the surface having a line of curvature;   generating a plurality of profile curves C( 1 )-C(d) by, for iterations i=1 to d:
 sweeping the profile curve C(i- 1 ) in a direction T(i- 1 ) from a point on the profile curve C(i- 1 ) to thereby generate a profile curve C(i), the direction T(i- 1 ) being a normal vector of a plane P(i- 1 ) that includes the profile curve C(i- 1 ); 
 wherein each iteration of the sweeping generates the profile curve C(i) by adjusting when necessary orientation of the profile curve C(i- 1 ) within the plane P(i), such that a collective path of the point for the profile curves tracks the line of curvature of the surface; and 
 generating a virtual model of the surface based on at least profile curve C( 0 ), profile curve C(d), and at least some of profile curves C( 1 )-C(d- 1 ).