Encoder based machining quality prognostics
AssigneeFord Global Technologies, LLC
InventorsYoussef Ziada, Ethan Timothy Hughey, Richard Earl Williford
Life of this patent
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Abstract
A method of measuring quality in a machining operation of a device includes measuring lost motion for at least one axis of the device during the machining operation, calculating a spindle lag of a spindle of the device during the machining operation, determining a lost motion deviation, determining a spindle lag deviation, and identifying a machining defect based on the lost motion deviation coinciding with the spindle lag deviation.
Claims20
A method of measuring quality in a machining operation of a device, the method comprising:
- measuring lost motion for at least one axis of the device during the machining operation;
- calculating a spindle lag of a spindle of the device during the machining operation;
- determining a lost motion deviation;
- determining a spindle lag deviation;
- and
- identifying a machining defect based on the lost motion deviation coinciding with the spindle lag deviation.
A method of measuring quality in a machining operation of a device including a spindle, the method comprising:
- performing a machining operation;
- measuring a first linear encoder position along a first axis during the machining operation;
- measuring a first rotary encoder position of a first motor during the machining operation, the first motor configured to move either the spindle or a workpiece along the first axis;
- calculating a difference between the first linear encoder position and the first rotary encoder position to determine a first axis lost motion;
- measuring an actual angular position of the spindle;
- comparing a desired angular position of the spindle to the actual angular position of the spindle to determine a spindle lag of a spindle;
- and
- identifying a machining defect based on a lost motion deviation coinciding with a spindle lag deviation.
A machining device comprising:
- a spindle configured to hold one of a tool or a workpiece;
- a spindle motor drivingly coupled to the spindle to rotate the spindle about a spindle axis;
- a first axis motor drivingly coupled to one of the spindle or a workpiece support and configured to move the one of the spindle or the workpiece support along a first linear axis;
- and
- a controller configured to identify a machining defect based on a first axis lost motion and a spindle lag, the first axis lost motion being lost motion along the first linear axis.
Dependencies are inferred from the claim text.