Calibration device for a parallel kinematic manipulator

A calibration device for measuring n deviations and determining m unknown spatial coordinates of a parallel kinematic manipulator having a base unit and a manipulator platform movable with respect to the base unit, the base unit being connected to the manipulator platform via a plurality of joints and having a workholding fixture for a tool, wherein the calibration device comprises:

• a test workpiece mountable in a defined spatial relation to the base unit;
• measuring mandrels numbering 1=m/n, arranged on the test workpiece in a known spatial position and a known spatial orientation with respect to a reference spatial position and a reference spatial orientation;
• a probing unit mountable on the workholding fixture of the manipulator platform;
• and
• n probing subsystems, each of the n probing subsystems including a distance measuring device for relative measurements, and being oriented with respect to each other of the n probing subsystems such that the probing unit is adapted for measuring the known spatial position and known spatial orientation of the measuring mandrels on the test workpiece;
• wherein m=36 and n=6;
• and
• wherein at least three of the probing subsystems of the probing unit are arranged so that their measuring directions are linearly independent of one another, and remaining probing subsystems are arranged so that their rotational deviations are obtainable from one differential measurement.

A calibration device for measuring n deviations and determining m unknown spatial coordinates of a parallel kinematic manipulator having a base unit and a manipulator platform movable with respect to the base unit, the base unit being connected to the manipulator platform via a plurality of joints and a plurality of variable-length actuators, and having a workholding fixture for a tool, wherein the calibration device comprises:

• a test workpiece mountable in a defined spatial relation to the base unit;
• measuring mandrels numbering l=m/n, arranged on the test workpiece in a known spatial position and a known spatial orientation with respect to a reference spatial position and a reference spatial orientation;
• a probing unit mountable on the workholding fixture of the manipulator platform;
• n probing subsystems, each of the n probing subsystems including a distance measuring device for relative measurements, and being oriented with respect to each other of the n probing subsystems such that the probing unit is adapted for measuring the known spatial position and known spatial orientation of the measuring mandrels on the test workpiece;
• and
• a reference measuring mandrel disposed on the test workpiece, defining the reference spatial position and reference spatial orientation, and such that the measuring mandrels are arranged in the known spatial position and orientation with respect to said reference plug;
• wherein the measuring mandrels are arranged on the test workpiece such that a maximum of three of the measuring mandrels have substantially the same spatial orientation and have spatial positions that are linearly independent of one another, and wherein the remaining measuring mandrels each have different spatial orientations with respect to the maximum of three measuring mandrels.

A calibration device for measuring six deviations and determining thirty-six unknown spatial coordinates of a parallel kinematic manipulator having a base unit and a manipulator platform movable with respect to the base unit, the base unit being connected to the manipulator platform via a plurality of joints and a plurality of variable-length actuators, and having a workholding fixture for a tool, wherein the calibration device comprises:

• a test workpiece mountable in a defined spatial relation to the base unit;
• measuring mandrels numbering six, arranged on the test workpiece in a known spatial position and a known spatial orientation with respect to a reference spatial position and a reference spatial orientation;
• a probing unit mountable on the workholding fixture of the manipulator platform;
• and
• six probing subsystems, each of the six probing subsystems including a distance measuring device for relative measurements, and being oriented with respect to each other of the six probing subsystems such that the probing unit is adapted for measuring the known spatial position and known spatial orientation of the measuring mandrels on the test workpiece;
• wherein at least three of the probing subsystems of the probing unit are arranged so that their measuring directions are linearly independent of one another, and remaining probing subsystems are arranged so that their rotational deviations are obtainable from one differential measurement.