Spatial difference measurement

A non-transitory computer readable medium comprising computer executable instructions configured to cause a computer to perform a method, the method comprising:

• generating first key features of a first skeleton of a nominal 3D model of an object;
• extrapolating the first key features onto the nominal 3D model;
• creating an actual 3D model of the object during or after a construction process of the object;
• generating second key features of a second skeleton of the actual 3D model of the object;
• extrapolating the second key features onto the actual 3D model of the object;
• and
• comparing the first key features extrapolated on the nominal 3D model to the second key features extrapolated on the actual 3D model to determine one or more distances between the first and second key features to measure a spatial difference between the nominal 3D model and the object during or after the construction process,
• wherein the method includes receiving the nominal 3D model of an object, and generating the first skeleton based on the nominal 3D model, wherein the method includes generating the second skeleton based on the actual 3D model, wherein generating the first skeleton includes converting the nominal 3D model into a first finite element mesh using median axis method.

A system, comprising:

• a spatial difference measurement module configured to:
• generate first key features of a first skeleton of a nominal 3D model of an object;
• extrapolate the first key features onto the nominal 3D model;
• create an actual 3D model of the object during or after a construction process of the object;
• generate second key features of a second skeleton of the actual 3D model of the object;
• extrapolate the second key features onto the actual 3D model of the object;
• compare the first key features extrapolated on the nominal 3D model to the second key features extrapolated on the actual 3D model to determine one or more distances between the first and second key features to measure a spatial difference between the nominal 3D model and the object during or after the construction process;
• receive the nominal 3D model of an object;
• generate the first skeleton based on the nominal 3D model, wherein generating the first skeleton includes converting the nominal 3D model into a first finite element mesh using median axis method;
• generate the second skeleton based on the actual 3D model, and
• output a spatial difference value.