Servo control method and servo control system for feed drive system
AssigneeToshiba Kikai Kabushiki Kaisha
InventorsMinoru Hamamura, Sadaji Hayama, Jun Fujita, Takao Date, Kazuo Nagashima
Life of this patent
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Abstract
Letting a differential value of a command value of a position command to a position control loop be an input variable, a feed forward compensation value is calculated depending on the input variable and a combination of a proper vibration frequency and an attenuation constant of a vibration in a moving direction of a moving mechanism to be set in a parameter setting manner, and a feed forward compensation is effected for the command value of the position command to the position control loop by the feed forward compensation value.
Claims42
A servo control method for a feed drive system including a moving mechanism controlled with a position control loop, the servo control method comprising the steps of:
- having a differential value of a first command value of a position command to the position control loop, as a first input variable;
- calculating a first feed forward compensation value depending on the first input variable and a combination of a proper vibration frequency and an attenuation constant of a vibration in a moving direction of the moving mechanism to be set in a first parameter setting manner;
- and
- effecting a feed forward compensation for the first command value of the position command to the position control loop by the first feed forward compensation value.
A servo control method for a feed drive system including a linear movement mechanism, the servo control method comprising the steps of:
- calculating a correction value corresponding to a quantity of an elastic deformation in a linear movement direction of the linear movement mechanism depending on a combination of an inertial force and a rigidity in the linear movement direction of the linear movement mechanism;
- and
- correcting a command value of a position command by the correction value.
A servo control method for a feed drive system including a linear movement mechanism, the servo control method comprising the steps of:
- having an acceleration and a rigidity in a linear movement direction of the linear movement mechanism, as a combination of first input variables;
- calculating a first correction value corresponding to a quantity of an elastic deformation in the linear movement direction of the linear movement mechanism depending on the combination of first input variables and a mass of the linear movement mechanism to be set in a parameter setting manner;
- and
- correcting a command value of a position command by the first correction value.
A servo control method for a feed drive system including a linear movement mechanism, the servo control method comprising the steps off:
- having a command value of a torque command to a servo motor and a rigidity in a linear movement direction of the linear movement mechanism as a combination of first input variables;
- calculating a first correction value corresponding to a quantity of an elastic deformation in the linear movement direction of the linear movement mechanism depending on the combination of first input variables;
- and
- correcting a command value of a position command by the first correction value.
A servo control method for a feed drive system including a linear movement mechanism having a pair of linear movement axes perpendicular to each other and controlled with a position control loop for a feed drive to be effected with an arcuate interpolation, the servo control method comprising the steps of:
- measuring a magnitude of maximum inertial torque acting about either linear movement axis;
- calculating a correction value corresponding to an elastic deformation in a linear movement direction of the linear movement mechanism at a respective coordinate position on a basis of the magnitude of maximum inertial torque;
- and
- correcting a command value of a position control loop by the correction value.
A servo control method for a feed drive system including a linear movement mechanism, the servo control method comprising the steps of:
- performing one of a computation and a measurement of a movement position of a moving body of the linear movement mechanism including an elastic deformation due to an inertial force;
- calculating a correction value in accordance with a difference between a command value of a position command and one of a computed value and a measured value of the movement position;
- and
- correcting the command value of the position command by the correction value.
A servo control system for a feed drive system including a moving mechanism, the servo control system comprising:
- a position control loop for a position control of the moving mechanism;
- and
- first pre-compensation means for having a differential value of a first command value of a position command to the position control loop, as a first input variable, calculating a first feed forward compensation value depending on the first input variable and a combination of a proper vibration frequency and an attenuation constant of a vibration in a moving direction of the moving mechanism to be set in a first parameter setting manner, and effecting a feed forward compensation for the first command value of the position command to the position control loop by the first feed forward compensation value.
A servo control system for a feed drive system including a linear movement mechanism, the servo control system comprising:
- control means for controlling a movement position of the linear movement mechanism with a position command;
- and
- first correction means for having an acceleration and a rigidity in a linear movement direction of the linear movement mechanism, as a combination of first input variables, calculating a first correction value corresponding to a quantity of an elastic deformation in the linear movement direction of the linear movement mechanism depending on the combination of first input variables and a mass of the linear movement mechanism to be set in a parameter setting manner, and correcting a command value of the position command by the first correction value.
A servo control system for a feed drive system including a linear movement mechanism, the servo control system comprising:
- control means for controlling a movement position of the linear movement mechanism with a position command and a magnitude of torque of an associated servo motor with a torque command;
- and
- first correction means for having a command value of the torque command and a rigidity in a linear movement direction of the linear movement mechanism, as a combination of first input variables, calculating a first correction value corresponding to a quantity of an elastic deformation in the linear movement direction of the linear movement mechanism depending on the combination of first input variables, and correcting a command value of the position command by the first correction value.
A servo control system for a feed drive system including a linear movement mechanism having a pair of linear movement axes perpendicular to each other, the servo control system comprising:
- control means for controlling a feed position of the linear movement mechanism with a position command covering an arcuate interpolation;
- and
- correction means for calculating a correction value corresponding to an elastic deformation in a linear movement direction of the linear movement mechanism at a respective coordinate position on a basis of a measured magnitude of maximum inertial torque acting about an associated linear movement axis, and correcting a command value of the position command by the correction value.
A servo control system for a feed drive system including a linear movement mechanism, the servo control system comprising:
- control means for controlling a movement position of the linear movement mechanism with a position command;
- and
- correction means for calculating a correction value in accordance with a difference between a command value of the position command and one of a computed value and a measured value of a moved position of a moving body of the linear movement mechanism including an elastic deformation due to an inertial force, and correcting the command value of the position command by the correction value.
A method of controlling a servo system including a servo motor for driving a feed mechanism of a numerically controlled machine tool to provide a precise feed in accordance with a drive command supplied to the servo motor, the method comprising the steps of:
- preparing an elastic mechanical model of an associated portion of the machine tool including the feed mechanism;
- sampling a data representative of a subsequent dynamic state of the feed mechanism;
- estimating a dynamic state of the elastic mechanical model on a basis of the sampled data;
- estimating a deformation of the elastic mechanical model under the estimated dynamic state;
- and
- controlling the drive command on a way of supply to the servo motor, to eliminate a probable error of the precise feed in the subsequent dynamic state of the feed mechanism, on a basis of the estimated deformation of the elastic mechanical model.
A system for controlling a servo system including a servo motor for driving a feed mechanism of a numerically controlled machine tool to provide a precise feed in accordance with a drive command supplied to the servo motor, the system comprising:
- an elastic mechanical model of an associated portion of the machine tool including the feed mechanism;
- a sampler for sampling a data representative of a subsequent dynamic state of the feed mechanism;
- an estimator for estimating a dynamic state of the elastic mechanical model on a basis of the sampled data, and for estimating a deformation of the elastic mechanical model under the estimated dynamic state;
- and
- a controller for controlling the drive command on a way of supply to the servo motor, to eliminate a probable error of the precise feed in the subsequent dynamic state of the feed mechanism, on a basis of the estimated deformation of the elastic mechanical model.
Dependencies are inferred from the claim text.