Classifications

• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B19/00—Programme-control systems
  • G05B19/02—Programme-control systems electric
  • G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
  • G05B19/19—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
  • G05D3/00—Control of position or direction
  • G05D3/12—Control of position or direction using feedback
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B2219/00—Program-control systems
  • G05B2219/30—Nc systems
  • G05B2219/41—Servomotor, servo controller till figures
  • G05B2219/41428—Feedforward of position and speed

Definitions

• the present invention relates to a control method of a support motor for driving a feed shaft, a robot arm, and the like of a machine tool, and more particularly to a method of performing feedforward control to improve command followability.
• feed-forward control is often used as a technique for improving command tracking performance.
• a method was generally used in which a differentiated position command was used as a speed feedforward command value, and another differentiated position command was used as a torque feedforward command value.
• FIG. 4 is a block diagram showing the configuration of the conventional system.
• the speed command Vref is obtained by multiplying the deviation between the position command 6ref and the actual position ⁇ b by a position loop gain Kp of 1.
• a value obtained by multiplying the value obtained by differentiating the position command value e re f in the differentiating unit 41 by a coefficient is set as a speed feed forward command V f f and added to the speed command V r e f.
• the deviation between the speed command Vref and the actual speed Vfb is calculated, and the speed loop process of 2 is performed to obtain the current command value Iref.
• a method is used in which a value obtained by differentiating the speed feed forward command V ff in the differentiator 42 and multiplying by the coefficient ⁇ is defined as a current feed forward If f f and adding the current feed forward I f f. According to this method, the response of the speed loop and the current loop is improved, and the response delay of the servo system is improved.
• Japanese Patent Application Laid-Open No. H10-149210 discloses a method for creating a command for a positioning control system, which has a configuration as shown in FIG.
• a method has been disclosed in which the transfer function including the mechanism is solved in reverse, and a position command is created in which the transfer function from the position command to the load position is set to 1, thereby improving command followability and achieving perfect tracking. I have.
• the symbols shown in FIG. 5 are the same as in FIG.
• An object of the present invention is to provide a servo control method that solves the above problems 1 and 2. Disclosure of the invention
• the present invention provides a servo control method using feedforward, in which the position of a load and the position of a motor are each represented by a function that can be differentiated to a higher order, and operating conditions and mechanical From the parameters, the higher-order differentiable function is determined, and the position, speed, and torque command of the motor are calculated from the determined higher-order differentiable function, and the calculated motor position, speed, and torque are calculated.
• the command value is used as a feedforward command.
• the higher-order differentiable function may be a 15th-order polynomial.
• the operating condition may be a moving distance and a moving time.
• FIG. 1 is a block diagram showing the configuration of Embodiment 1 of the present invention.
• FIG. 2 shows an embodiment of the present invention.
• FIG. 9 is a block diagram illustrating a configuration of a second embodiment.
• FIG. 3 is a flowchart illustrating the processing procedure of the present invention.
• FIG. 4 is a block diagram illustrating the configuration of Conventional Example 1.
• FIG. 5 is a block diagram illustrating the configuration of Conventional Example 2.
• FIG. 1 is a block diagram showing an embodiment of the present invention.
• 1 is a position loop proportional gain Kp
• 2 is a speed loop
• 3 is a command generation portion for calculating a motor position, speed, and torque command.
• 4 is a desired operating condition, which is stored in the memory.
• Numeral 5 indicates the parameters of the mechanism, which are stored in the memory.
• the proportional integral control is performed. Further, as described in claim 4, as the operating condition of 4, the moving S giant separation di st and the moving time te are input and stored. As the parameters of the mechanism 5, it is assumed that the motor inertia Jl, the load inertia J2, the spring constant Kc, and the damping coefficient DL are inputted and stored.
• T ref (t) J 1Xm (2) (t) + J 2X 1 (2) (t)
• the torque command value Tr ef (t) is derived by the procedure of the first embodiment. Put out.
• the controller has a mechanical model in advance, inputs the derived torque command to the mechanical model, and calculates the motor position and motor speed calculated in the model. , A feedforward command value. In this method, only the torque command needs to be input to the control calculator, and the same effect as in the first embodiment can be obtained.
• the position of the mechanism and the position of the motor are represented by a higher-order differentiable polynomial, the boundary conditions obtained from the operating conditions (moving distance and moving time), and the equation of motion of the mechanism. From the above, the coefficients of the polynomial are determined, and finally, the motor position command, motor speed command, and motor torque command are calculated, and these are used as the feedforward command values. There is an effect that it is possible to follow.
• the same command can be used even when the control system gain or the like is changed. Therefore, even when the feedforward command is calculated in advance in offline processing, the trouble of recalculation and the like is reduced. There is an effect that does not take. Industrial applicability
• a flexible structure having two or more inertia connected via a spring element can completely follow a command.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Automation & Control Theory (AREA)
• Human Computer Interaction (AREA)
• Manufacturing & Machinery (AREA)
• Control Of Electric Motors In General (AREA)
• Control Of Position Or Direction (AREA)
• Feedback Control In General (AREA)
• Manipulator (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=18768651

Family Applications (1)

Country Status (7)

Families Citing this family (12)

Citations (4)

Family Cites Families (14)

• 2000
  • 2000-09-20 JP JP2000284444A patent/JP2002091570A/ja not_active Abandoned
• 2001
  • 2001-09-10 KR KR1020037003929A patent/KR100842978B1/ko not_active Expired - Fee Related
  • 2001-09-10 EP EP01963570A patent/EP1338937A4/en not_active Withdrawn
  • 2001-09-10 US US10/380,827 patent/US20030173928A1/en not_active Abandoned
  • 2001-09-10 WO PCT/JP2001/007851 patent/WO2002025390A1/ja not_active Ceased
  • 2001-09-10 CN CNB018158528A patent/CN100343767C/zh not_active Expired - Fee Related
  • 2001-09-19 TW TW090123112A patent/TW525045B/zh not_active IP Right Cessation

Patent Citations (4)

Non-Patent Citations (1)

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