Method for controlling force application with servo motor and appartus therewith
AssigneeFanuc Corporation
InventorsTETSUAKI KATO, KOICHI OKANDA
Life of this patent
Estimating the term…
Abstract
An applied force Td is estimated by an observer. A gain A is multiplied by a value obtained by subtracting the estimated applied force Td from commanded force Fc. From this multiplied value, product of a speed feedback amount and a gain Kv is subtracted to obtain a torque command. With this torque command Tc, servo motor (2) is driven. Since feedback control of applied force is performed, response is fast, and applied force can be accurately controlled. Feedback control of an applied force whose vibration is prevented can be performed by adjusting the gains A and Kv.
Claims10
A method for controlling force application with a servo motor, in which an applied force of a movable object driven by the servo motor to another object is controlled, comprising:
- a step of forming a force control loop with an applied force commanded to the servo motor and an applied force estimated by an observer;
- and
- a step of performing feedback control of the applied force.
An apparatus for controlling force application with a servo motor that controls an applied force of a movable object, driven by the servo motor, to another object, comprising:
- an observer estimating the applied force;
- and
- force control loop processing execution means for performing force feedback control with an applied force commanded to the servo motor and the applied force estimated by the observer.
An apparatus for controlling force application with a servo motor, comprising:
- a controller outputting a force application control command;
- applied-force estimation means for estimating an applied force produced when a movable object is driven by the servo motor and pressed to another object in accordance with force application control command from the controller;
- speed detection means for detecting an actual speed of the servo motor;
- and
- torque command means for calculating a torque command Tc outputted to the servo motor with using the following equation:
- Tc=A*(Fc−Td)−Kv*v
- and outputting the torque command to the servo motor, where A and Kv are coefficients, Fc is a force application control command outputted from the controller, Td is an applied force estimated in the applied-force estimation means, and v is speed of the servo motor detected by the speed detection means.
Dependencies are inferred from the claim text.