Robotic arm alignment

1. A method for aligning the position of a movable arm comprising:

providing an alignment element on the apparatus projecting a distance above the apparatus in the z-direction and having a surface lying in a plane formed by an x and y axis;

providing a movable arm having a tool at the free end;

positioning the object such that the surface of the element faces the tool;

moving the tool in a direction towards the surface of the element;

sensing when the tool reaches a predetermined point on or above the surface of the element, whereby the position of the tool in the z-direction is determined based on the relationship between the measured response of the tool and the height of the tool above the surface of the alignment element;

placing the tool on or at a distance in the z-direction from the surface;

moving the tool in the x-direction while sensing the surface of the element;

moving the tool in the x-direction until an edge of the element is sensed;

determining the center in the x-direction based on the known distance the tool has moved and the known dimensions of the element in the x-direction;

placing the tool on or at a distance in the z-direction from the surface;

moving the tool in the y-direction while sensing the surface of the element;

moving the tool in the y-direction until an edge of the element is sensed; and

determining the center in the y-direction based on the known distance the tool has moved and the known dimensions of the element in the y-direction.

2. A method for aligning as claimed in claim 1 , wherein the surface of the element is perpendicular to the tool in the z-direction.

3. A method for aligning as claimed in claim 1 , wherein the tool is a metering probe.

4. A method for aligning as claimed in claim 3 , wherein the metering probe has a disposable tip on the end thereof.

5. A method for aligning as claimed in claim 3 , wherein the measured response is the air pressure in the probe.

6. A method for aligning as claimed in claim 3 , wherein the metering probe has a source of compressed air for expelling air out of the end of the probe and a pressure transducer for measuring the air pressure inside the metering probe.

7. A method as claimed in claim 6 , wherein the pressure inside the metering probe increases as the probe approaches the surface of element.

8. A method as claimed in claim 7 , wherein the distance of the probe from the surface of the element is detected when the pressure reaches a predetermined threshold.

9. A method as claimed in claim 3 , wherein the metering probe has one of an optical sensor, capacitive sensor, or mechanical feeler gauge.

10. A method for aligning as claimed in claim 3 , wherein the metering probe has a vacuum source for drawing air into the end of the probe and a vacuum gauge for measuring the air pressure inside the metering probe.

11. A method as claimed in claim 1 , wherein the apparatus is a diagnostic analyzer.

12. A method as claimed in claim 1 , wherein the x, y and z directions are orthogonal to one another.

13. A method for aligning the position of a movable arm comprising:

providing an alignment element on the apparatus projecting a distance above the apparatus in the z-direction and having a surface lying in a plane formed by an x and y axis, wherein the dimensions of the element in the y and z directions are known;

providing a movable arm having a tool at the free end;

positioning the object such that the surface of the element faces the tool;

moving the tool in a direction towards surface of the element;

sensing when the tool reaches a predetermined point on or above the surface of the element, whereby the position of the tool in the z-direction is determined based on the monotonic relationship between the measured response of the tool and the height of the tool above the surface of the alignment element;

placing the tool on or at a distance in the z-direction from the surface;

moving the tool in a positive x-direction while sensing the surface of the element until an edge of the element is sensed;

moving the tool in a negative x-direction while sensing the surface of the element until the other edge of the element is sensed;

determining the center of the element along the x-axis using the edges sensed by the tool in the positive and negative x-directions;

placing the tool on or at a distance in the z-direction from the surface;

moving the tool in a positive y-direction while sensing the surface of the element until an edge of the element is sensed;

moving the tool in a negative y-direction while sensing the surface of the element until the other edge of the element is sensed;

determine the center of the element along the y-axis using the edges sensed by the tool in the positive and negative y-directions; and

determining the center of the element based on the known centers along the x and y-axis.

14. A method for aligning as claim in claim 13 , further comprising moving the tool to the center of the element along the x-axis after determining the center of the element along the x-axis.

15. A method for aligning as claim in claim 13 , wherein the element is round.

16. A method for aligning as claimed in claim 13 , wherein the surface of the element is perpendicular to the tool in the z-direction.

17. A method for aligning as claimed in claim 13 , wherein the tool is a metering probe.

18. A method for aligning as claimed in claim 17 , wherein the metering probe has a disposable tip on the end thereof.

19. A method for aligning as claimed in claim 17 , wherein the measured response is the air pressure in the probe.

20. A method for aligning as claimed in claim 17 , wherein the metering probe has a source of compressed air for expelling air out of the end of the probe and a pressure transducer for measuring the air pressure inside the metering probe.

21. A method as claimed in claim 20 , wherein the pressure inside the metering probe increases as the probe approaches the surface of element.

22. A method as claimed in claim 21 , wherein the distance of the probe from the surface of the element is detected when the pressure reaches a predetermined threshold.

23. A method as claimed in claim 21 , wherein the x, y and z directions are orthogonal to one another.

24. A method as claimed in claim 17 , wherein the metering probe has one of an optical sensor, capacitive sensor, or mechanical feeler gauge.

25. A method for aligning as claimed in claim 17 , wherein the metering probe has a vacuum source for drawing air into the end of the probe and a vacuum gauge for measuring the air pressure inside the metering probe.

26. A method as claimed in claim 13 , wherein the apparatus is a diagnostic analyzer.

27. A method as claimed in claim 13 , wherein the x, y and z directions are orthogonal to one another.

28. A method for aligning the position of a movable arm comprising: providing an alignment element on the apparatus projecting a distance above the apparatus in the z-direction and having a surface lying in the plane formed by an x and y axis, and a recess in the surface, said recess extending in the z-direction;

providing a movable arm having a tool at the free end;

positioning the object such that the surface of the element faces the tool;

moving the tool in a direction towards surface of the element;

sensing when the tool reaches a predetermined point on or above the element, whereby the position of the tool in the z-direction is determined based on the relationship between the measured response of the tool and the height of the tool above a flat surface of the alignment element;

placing the tool on or at a known distance in the z-direction from the surface;

moving the tool in the x-direction toward the recess while sensing the surface of the element;

moving the tool in the x-direction until a first edge of the recess is sensed and continuing to move the tool until a second edge of the recess is sensed;

determining the center of the recess in the x-direction based on the sensed edges;

placing the tool on or a at a distance in the z-direction from the surface;

moving the tool in the y-direction until a first edge of the recess is sensed and continuing to move the tool until a second edge of the recess is sensed; and

determining the center of the recess in the y-direction based on the sensed edges.

29. A method for aligning as claimed in claim 28 , wherein the surface of the element is perpendicular to the tool in the z-direction.

30. A method for aligning as claimed in claim 28 , wherein the tool is a metering probe.

31. A method for aligning as claimed in claim 30 , wherein the metering probe has a disposable tip on the end thereof.

32. A method for aligning as claimed in claim 30 , wherein the measured response is the air pressure in the probe.

33. A method for aligning as claimed in claim 32 , wherein the metering probe has a source of compressed air for expelling air out of the end of the probe and a pressure transducer for measuring the air pressure inside the metering probe.

34. A method as claimed in claim 33 , wherein the pressure inside the metering probe increases as the probe approaches the surface of element.

35. A method as claimed in claim 34 , wherein the distance of the probe from the surface of the element is detected when the pressure reaches a predetermined threshold.

36. A method as claimed in claim 30 , wherein the metering probe has one of an optical sensor, capacitive sensor, or mechanical feeler gauge.

37. A method for aligning as claimed in claim 30 , wherein the metering probe has a vacuum source for drawing air into the end of the probe and a vacuum gauge for measuring the air pressure inside the metering probe.

38. A method as claimed in claim 28 , wherein the apparatus is a diagnostic analyzer.

39. A method for calibrating as claimed in claim 28 further comprising, determining the center of the recess based on the known centers along the x and y-axis.