Methods and systems for calibration of a positional orientation between a sample container and nozzle tip

摘要

Disclosed are methods to aid in a calibration of a vertical orientation of a nozzle tip to a sample container in a processing or testing system. The method includes positioning the nozzle over a calibration target at a home height location (HM), moving the nozzle downward a distance (D) until contact with the calibration target is sensed, positioning the nozzle over the sample rack and moving the nozzle downward until contact with a registration location is sensed, imaging the sample rack and calibration target to determine a height (H) between the registration location and calibration target, and calculating a translation ratio (TR) between the height (H) measured in pixel space and the distance (D) measured in machine space. The translation ratio (TR) may be used to drive the nozzle tip to a predetermined depth. A robot calibration system is disclosed, as are other aspects.

主权项

1. A method of calibrating a position of a nozzle tip relative to a sample container, comprising:
providing a nozzle including a nozzle tip, the nozzle operably configured to aspirate a sample fluid from the sample container; providing a sample rack having a receptacle configured to contain the sample container during the aspirate the sample rack having a registration location; inserting a calibration target in the receptacle of the sample rack; positioning the nozzle over the calibration target at a home height location (HM); moving the nozzle downward from the home height location (HM) a distance (D) until a portion of the calibration target is sensed; positioning the nozzle over the sample rack; moving the nozzle downward until a portion of the registration location of the sample rack is sensed to determine a distance (R) from the home height location (HM) to the registration location; imaging the assembly of the sample rack and the calibration target to determine a height (H) between the registration location and a top of the calibration target in pixel space; and calculating a translation ratio (TR) between the height (H) measured in the pixel space and the height (M) measured in machine space, wherein (M) is related to distance (R) and height (H); wherein each of distance (D) and distance (R) is measured in a number of steps (S) of a stepper motor; the method further comprising: generating the translation ratio (TR) between the number of steps (S) and the height (H); and using the translation ratio (TR) to drive the nozzle tip to a predetermined drive depth (DD) in a sample container.