System and method for creating a datum reference frame

1. A computer-implemented method for creating a datum reference frame, comprising:

selecting a first datum, wherein the first datum comprises a plurality of faces;

determining a first definition for the selected first datum;

automatically determining a set of one or more valid second datums based on the determined first definition, wherein the second datum comprises a plurality of faces;

selecting the second datum from the set of valid second datums;

determining a second definition for the selected second datum;

automatically determining a set of one or more valid third datums based on the determined second definition, wherein the third datum comprises a plurality of faces; and

selecting the third datum from the set of valid third datums.

2. The method of claim 1 , wherein determining the first definition for the selected first datum comprises:

determining the existence of one or more faces comprising an axis; and

selecting the axis as the first definition.

3. The method of claim 1 , wherein determining the second definition for the selected second datum comprises:

determining the existence of one or more faces comprising an axis; and

selecting the axis as the second definition.

4. The method of claim 1 , wherein determining the first definition for the selected first datum comprises:

determining the existence of one or more faces comprising a plane; and

selecting the plane as the first definition.

5. The method of claim 1 , wherein determining the second definition for the selected second datum comprises:

determining the existence of one or more faces a plane; and

selecting the plane as the second definition.

6. The method of claim 1 , wherein determining the first definition for the selected first datum comprises:

determining the existence of three or more targets comprising a plane; and

selecting the plane as the first definition.

7. The method of claim 1 , wherein determining the second definition for the selected second datum comprises:

determining the existence of three or more targets comprising a plane; and

selecting the plane as the second definition.

8. The method of claim 2 , wherein automatically determining the set of one or more valid second datums based on the determined first definition comprises selecting a plane, wherein the scalar product of the normal of the plane and the axis is zero, one, or negative one.

9. The method of claim 2 , wherein the axis comprises a first axis and automatically determining the set of one or more valid second datums based on the determined first definition comprises selecting one or more second datums based on the determined first definition comprises determining one or more second axes, wherein the scalar product of the first axis and the second axis is zero or the scalar product of the first axis and the second axis is one or negative one and the first axis and the second axis are not coaxial.

10. The method of claim 4 , wherein automatically determining the set of one or more second valid datums based on tie determined first definition comprises:

calculating the normal of the plane, wherein the plane comprises a first plane; and

selecting a second plane, wherein the scalar product of the normal of the second plane and the normal of the first plane is zero.

11. The method of claim 4 , wherein automatically determining a set of one or more valid second datums based on the determined first definition comprises:

calculating the normal of the plane; and

selecting an axis, wherein the scalar product of the axis and the normal of the first plane is zero, one, or negative one.

12. The method of claim 8 , wherein automatically determining the set of one or more valid third datums based on the determined second definition comprises:

calculating the normal of the plane, wherein the plane comprises a first plane; and

selecting a second plane, wherein the scalar product of the normal of the second plane and the normal of the first plane is zero and the scalar product of the normal of the first plane and the axis is one or negative one and the scalar product of the axis and the second plane is zero.

13. The method of claim 10 , wherein automatically determining the set of one or more valid third datums based on the determined second definition comprises selecting a third plane wherein the scalar product of the normal of the first plane and the normal of the second plane is zero and the scalar product of the normal of the first plane and the normal of third plane is zero and the scalar product of the normal of the second plane and the normal of third plane is zero.

14. The method of claim 1 , wherein the first datum, the second datum, and the third datum are selected from a group of the following:

a plane;

a slot;

a pin;

a tapered pin;

an elongated hole;

a torus;

a ball/socket;

a revolved;

a bounded; and

a thickness.

15. A computer-implemented system for creating a datum reference frame, the system comprising logic encoded in media and operable to:

select a first datum, wherein the first datum comprises a plurality of faces;

determine a first definition for the selected first datum;

automatically determine a set of one or more second valid datums based on the determined first definition, wherein the second datum comprises a plurality of faces;

select the second datum from the set of valid second datums;

determine a second definition for the selected second datum;

automatically determine a set of one or more valid third datums based on the determined second definition, wherein the third datum comprises a plurality of faces; and

select the third datum from the set of valid third datums.

16. The system of claim 15 , wherein logic operable to determine the first definition for the selected first datum comprises logic operable to:

determine the existence of one or more faces comprising an axis; and

select the axis as the first definition.

17. The system of claim 15 , wherein logic operable to determine the second definition for the selected second datum comprises logic operable to:

determine the existence of one or more aces comprising an axis; and

select the axis as the second definition.

18. The system of claim 15 , wherein logic operable to determine the first definition for the selected first datum comprises logic operable to

determine the existence of one or more faces comprising a plane; and

select the plane as the first definition.

19. The system of claim 15 , wherein logic operable to determine the second definition for the selected second datum comprises logic operable to:

determine the existence of one or more faces a plane; and

select the plane as the second definition.

20. The system of claim 15 , wherein logic operable to determine the first definition for the selected first datum comprises logic operable to:

determine the existence of three or more targets comprising a plane; and

select the plane as the first definition.

21. The system of claim 15 , wherein logic operable to determine the second definition for the selected second datum comprises logic operable to:

determine the existence of three or more targets comprising a plane; and

select the plane as the second definition.

22. The system of claim 16 , wherein the logic operable to automatically determine the set of one or more valid second datums based on the determined first definition comprises logic operable to select a plane, wherein the scalar product of the normal of the plane and the axis is zero, one, or negative one.

23. The system of claim 16 , wherein the axis comprises a first axis and the logic operable to automatically determine the set of one or more valid second datums based on the determined first definition comprises logic operable to select one or more second datums based on the determined first definition comprises determining one or more second axes, wherein the scalar product of the first axis and the second axis is zero or the scalar product of the first axis and the second axis is one or negative one and the first axis and the second axis are not coaxial.

24. The system of claim 18 , wherein the logic operable to automatically determine the set of one or more valid second datums based on the determined first definition comprises logic operable to:

calculate the normal of the plane, wherein the plane comprises a first plane; and

select a second plane, wherein the scalar product of the normal of the second plane and the normal of the first plane is zero.

25. The system of claim 18 , wherein the logic operable to automatically determine the set of one or more valid second datums based on the determined first definition comprises logic operable to:

calculate the normal of the plane; and

select an axis, wherein the scalar product of the axis and the normal of the first plane is zero, one, or negative one.

26. The system of claim 22 , wherein the logic operable to automatically determine the set of one or more valid third datums based on the determined second definition comprises logic operable to:

calculate the normal of the plane, wherein the plane comprises a first plane; and

select a second plane, wherein the scalar product of the normal of the second plane and the normal of the first plane is zero and the scalar product of the normal of the first plane and the axis is one or negative one and the scalar product of the axis and the second plane is zero.

27. The system of claim 24 , wherein the logic operable to automatically determine the set of one or more valid third datums based on the determined second definition comprises logic operable to select a third plane wherein the scalar product of the normal of the first plane and the normal of the second plane is zero and the scalar product of the normal of the first plane and the normal of third plane is zero and the scalar product of the normal of the second plane and the normal of third plane is zero.

28. The system of claim 15 , wherein the first datum, the second datum, and the third datum are selected from a group of the following:

a plane;

a slot;

a pin;

a tapered pin;

an elongated hole;

a torus;

a ball/socket;

a revolved;

a bounded; and

a thickness.