Automated work piece moment of inertia (MOI) identification system and method for same

A method for automatically identifying a moment of inertia (MOI) of a work piece comprising:

• coupling a work piece to an effector assembly, the effector assembly coupled with a robotic arm capable of six-axis motion including three-axis translation and three-axis rotation, the effector assembly includes:
• a work piece interface configured to grasp and hold the work piece;
• a torque sensor configured to measure torque transmitted from the work piece to the effector assembly;
• and
• a motion feedback sensor configured to measure motion of the work piece about each said axis, the motion feedback sensor is coupled with at least one of the effector assembly or the robotic arm;
• determining an MOI for each of three orthogonal orientations of the work piece established by the robotic arm including:
• rotating the effector assembly and the work piece about an axis parallel to a gravity vector and through a center of mass of the work piece with the robotic arm;
• measuring with the torque sensor at least a first torque as the work piece is rotating about the axis;
• measuring with the motion sensor at least a first rotation of the work piece about the axis;
• and
• identifying the MOI for the orientation according to at least the measured first torque and first rotation.

A method for automatically identifying a center of mass and a moment of inertia (MOI) of a work piece comprising:

• coupling a work piece to an effector assembly having a force/torque sensor, the effector assembly coupled proximate an end of a manipulator assembly, the manipulator assembly includes a motion feedback sensor configured to measure motion of the work piece;
• identifying the center of mass of the work piece including:
• positioning the effector assembly and the work piece in at least two different static orientations relative to a gravity vector with the manipulator assembly;
• measuring a force and a torque in the different static orientations with the force/torque sensor of the effector assembly;
• and
• identifying a work piece center of mass according to the force and torque measurements;
• and
• identifying the moment of inertia of the work piece including:
• moving the effector assembly and the work piece dynamically in a three-axis coordinate system with the manipulator assembly including at least rotation of the work piece about each of the three axes;
• measuring at least a first torque for each of the three axes as the work piece is moving with the force/torque sensor of the effector assembly;
• measuring the motion of the work piece including at least a first rotation about each of the three axes;
• and
• identifying the MOI in each of the three axis according to at least the measured first torque and first rotation about each of the three axes.

A method for automatically identifying a center of mass and a moment of inertia (MOI) of a work piece comprising:

• coupling a work piece to an effector assembly having a force/torque sensor, the effector assembly coupled proximate and end of a manipulator assembly, the manipulator assembly includes a motion feedback sensor configured to measure motion of the work piece;
• identifying the center of mass and the moment of inertia of the work piece including:
• moving the effector assembly and the work piece in a three-axis coordinate system with the manipulator assembly, said motion including at least rotation of the work piece about each of the three axes;
• measuring with the force/torque sensor of the effector assembly at least a first force and at least a first torque for each of the three axes as the work piece is moving;
• measuring with the motion feedback sensor the movement of the work piece including at least a first rotation of the workpiece about each of the three axes;
• and
• identifying the MOI and center of mass in each of the three axes according to at least the measured first force and first torque and first rotation for each of the three axes.

A system configured for manipulation of a work piece and determination of a moment of inertia (MOI) of the work piece comprising:

• a manipulator assembly including an effector assembly and a manipulator arm having two or more members interconnected with actuators at joints,
• the effector assembly is coupled with the manipulator arm proximate an end of the manipulator arm, and the effector assembly includes:
• a work piece interface configured to grasp and hold a work piece while the manipulator assembly dynamically moves the effector assembly and the work piece in a three-axis coordinate system;
• and
• a force/torque sensor configured to measure force and torque transmitted from the work piece to the effector assembly;
• a feedback motion sensor coupled with the manipulator assembly, the feedback motion sensor configured to measure motion of the work piece;
• and
• a MOI determination module in communication with the manipulator assembly and the force/torque sensor, the MOI determination module includes:
• a manipulation element, the manipulation element configured to move the manipulator arm with the actuators at joints, the effector assembly and the work piece coupled with the effector assembly dynamically through the three-axis coordinate system including rotation of the work piece at least about each of the three axes;
• a force and torque measurement element configured to measure the force and torque of the work piece in each of the three axes with the force/torque sensor;
• a feedback motion sensor element configured to measure motion of the work piece including rotation about each of the three axes with the feedback motion sensor;
• and
• an identification element in communication with the force and torque measurement element and feedback motion sensor element, the identification element configured to identify the MOI according to at least the torque measurements and motion measurements conducted as the work piece moves and rotates about each of the three axes.