Method and apparatus for automatically tuning feedforward parameters

A method for tuning feedforward parameters in a motion control system having an actuator that controls motion of an attached mechanical member, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and the attached mechanical member;
• recording operation data associated with the actuator during the movement;
• and
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data, wherein the feedforward parameters are calculated based upon an equation relating the sum of torques acting on the actuator with angular acceleration of the actuator, wherein the operation data is inserted into the equation.

A method for tuning feedforward parameters in a motion control system having an actuator that controls motion of an attached mechanical member, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and the attached mechanical member;
• recording operation data associated with the actuator during the movement;
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data;
• and
• determining the accuracy of the calculated feedforward parameters, wherein the determining step comprises:
• calculating a theoretical motor torque based upon the calculated feedforward parameters;
• and
• calculating a coherence value based upon the theoretical motor torque and a measured motor torque command, wherein the coherence value corresponds to the degree of confidence in the accuracy of the calculated feedforward parameters.

A method for tuning feedforward parameters in a motion control system having an actuator that controls motion of an attached mechanical member, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and the attached mechanical member;
• recording operation data associated with the actuator during the movement;
• and
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data, wherein the command signals cause successive positive and negative movements of the actuator, wherein the operation data comprises a plurality of actuator velocity measurements and a plurality of actuator torque commands corresponding to the velocity measurements, and wherein the feedforward parameters are calculated based upon an equation relating the sum of torques acting on the actuator with angular acceleration of the actuator.

A method for tuning feedforward parameters in a motion control system having an actuator that controls motion of an attached mechanical member, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and the attached mechanical member;
• recording operation data associated with the actuator during the movement;
• and
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data, wherein the calculating step comprises:
• determining a model for various forces acting on the actuator;
• establishing an equation based upon the model;
• and
• calculating the feedforward parameters by inserting the operation data into the equation.

A method of automatically tuning feedforward parameters for control of an actuator in a motion control system, the method comprising:

• providing data regarding actuator movement limits;
• automatically determining a test motion routine for control of the actuator, wherein the test motion routine is configured to assist in determining feedforward parameters and is based upon the actuator movement limits;
• moving the actuator according to the test motion routine;
• and
• determining feedforward parameters based upon measurements taken during the test motion routine.

A method of automatically tuning feedforward parameters for control of an actuator in a motion control system, the method comprising:

• providing data regarding actuator movement limits;
• automatically determining a test motion routine for control of the actuator based upon the actuator movement limits;
• moving the actuator according to the test motion routine, wherein the test motion routine produces a bi-directional actuator movement, wherein the bi-directional actuator movement includes movement of the actuator with a positive velocity and movement of the actuator with a negative velocity, wherein an amount of time during which the actuator is moved with a positive velocity during the bi-directional movement is approximately equal to the amount of time during which the actuator is moved with a negative velocity during the bi-directional movement;
• and
• determining feedforward parameters based upon measurements taken during the test motion routine.

A computer readable medium having encoded thereon a method for automatically tuning feedforward parameters, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and an attached mechanical member;
• measuring operation data associated with the actuator during the movement;
• and
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data, wherein the feedforward parameters are calculated based upon an equation relating the sum of torques acting on the actuator with angular acceleration of the actuator.

A machine tool, comprising:

• an actuator having an attached mechanical member;
• a velocity sensor in communication with the actuator and adapted to sense the velocity of the actuator;
• a position command generator adapted to produce position commands to control the actuator;
• a feedforward command generator adapted to produce feedforward commands based upon a feedforward gain;
• a controller in communication with the actuator, sensor, position command generator, and feedforward command generator, and adapted to control a motion of the actuator based upon the position commands, feedforward commands, and actuator velocity;
• a feedforward tuning unit in communication with the velocity sensor, and adapted to calculate a value for the feedforward gain based upon velocity measurements from the velocity sensor;
• and
• an output device in communication with the feedforward tuning unit and adapted to communicate the calculated value for feedforward gain.

A method of automatically tuning compensation parameters for control of an actuator in a motion control system, the method comprising:

• receiving data regarding actuator movement;
• automatically determining a test motion routine for control of an actuator based upon the data received, wherein the test motion routine is configured to excite modes of behavior modeled by compensation parameters;
• moving the actuator according to the test motion routine;
• determining a sufficiency of the test motion routine based upon measurements associated with a motion;
• and
• determining values for the compensation parameters based upon measurements associated with the motion.

A method for tuning feedforward parameters in a motion control system having an actuator that controls motion of an attached mechanical member, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and the attached mechanical member;
• recording operation data associated with the actuator during the movement;
• and
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data;
• wherein the command signals cause a series of pairs of forward and reverse movements of the actuator, each forward movement of the actuator beginning from a start position, and each reverse movement returning the actuator to the start position.

A method for tuning feedforward parameters in a motion control system having an actuator that controls motion of an attached mechanical member, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and the attached mechanical member;
• recording operation data associated with the actuator during the movement;
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data;
• and
• comparing the feedforward parameters to previously calculated feedforward parameters.

A computer readable medium having encoded thereon a method for automatically tuning feedforward parameters, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and an attached mechanical member;
• measuring operation data associated with the actuator during the movement;
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data;
• and
• comparing the feedforward parameters to previously calculated feedforward parameters.

A computer readable medium having encoded thereon a method for automatically tuning feedforward parameters, the method comprising:

• applying command signals to an actuator to cause movement of the actuator and an attached mechanical member;
• measuring operation data associated with the actuator during the movement;
• calculating feedforward parameters for control of the actuator and attached mechanical member based upon the operation data;
• and
• wherein the command signals cause a series of pairs of forward and reverse movements of the actuator, each forward movement of the actuator beginning from a start position, and each reverse movement returning the actuator to the start position.