Motor control device and mechanical device

Abstract

A motor control device is provided with: a first motor (2) and a second motor (3) provided on a stand (1); a second controller (13) that determines a second deviation suppression signal in which a second motor (3) is driven such that the difference between a signal based on a second position command specifying the position of a movable element (3b) of the second motor (3) and a second motor position signal indicating the relative position of the movable element (3b) and a fixed element (3a) of the second motor (3) becomes small; a stand state estimator (15) that determines a stand model position, which is an estimated value of the absolute position of the stand (1) that is elastically deformed by the reaction force of the driving of the movable element (2b) of the first motor (2), on the basis of a reference driving force signal, which is a signal indicating the force for driving the movable element (2b) of the first motor (2); a correction amount determiner (16A) that determines a displacement correction signal on the basis of the stand model position; and a calculator (17) that determines a corrected motor drive signal for driving the second motor (3) on the basis of the displacement correction signal and the second deviation suppression signal.

Description

Technical Field

[0001] The present invention relates to a motor control device and a mechanical device for controlling a plurality of motors installed on a gantry. Background Art

[0002] Industrial machinery such as electronic component mounting machines, exposure equipment, and machine tools require high-speed and high-precision control performance. One example of an industrial machinery is a device in which two motors are installed on a gantry. In this device, the control performance of one motor may deteriorate due to the influence of the acceleration and deceleration of the other motor, and control is required to eliminate the influence between the axes.

[0003] In the interference non-interference compensation device of the positioning control system described in Patent Document 1, the interference non-interference compensator for performing interference non-interference compensation on the observed quantity of the driving body on the side affected by the interference has: a first feedforward compensator F nl (s), which is the operating amount u of the driving body on the interference occurrence side b As input, the output feedforward compensation u c , the feedforward compensation u c Used to observe the amount x of the driving body on the side affected by the disturbance lm The interference of the non-interference compensation; and the first operator, which through the first feedforward compensator F nl The output of the operation amount C1(s) of the driving body on the side affected by the disturbance is corrected.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2010-204878 Summary of the invention

[0005] However, the interference non-interference compensator of the positioning control system described in Patent Document 1 has the problem that a long time is required to adjust the compensator for non-interference of the influence between the axes. That is, the prior art has the problem that it is not possible to provide a motor control device that can adjust the compensator for non-interference of the influence between the axes in a short time and can suppress the interference between the axes.

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to obtain a motor control device capable of suppressing interference between axes and adjusting a compensator that eliminates interference between axes in a short time.

[0007] In order to solve the above-mentioned problems and achieve the purpose, the motor control device involved in the present invention has: a first motor, which is installed on the platform; a second motor, which is installed on the platform and is different from the first motor; and a second controller, which determines a second deviation suppression signal, which is a signal for driving the second motor so that the difference between the signal based on the second position instruction specifying the position of the movable part of the second motor and the second motor position signal indicating the relative position of the movable part of the second motor and the fixed part of the second motor becomes smaller. The motor control device involved in the present invention also has: a platform state estimator, which determines an estimated value of the absolute position of the platform elastically deformed by the reaction force of the driving of the movable part of the first motor, i.e., a platform model position, based on a signal indicating the force driving the movable part of the first motor, i.e., a reference driving force signal; a correction amount determiner, which determines a displacement correction signal based on the platform model position determined by the platform state estimator; and

[0008] The computing unit determines a correction motor drive signal for driving the second motor based on the displacement correction signal determined by the correction amount determiner and the second deviation suppression signal determined by the second controller.

[0009] Effects of the Invention

[0010] The motor control device according to the present invention has the effect of being able to suppress interference between axes and to adjust the compensator for eliminating the influence between axes in a short time. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a top view of a mechanical device with two electric motors.

[0012] Figure 2 is a side view of a mechanical device having two electric motors.

[0013] Figure 3 1 is a diagram showing a configuration of a system including the motor control device according to the first embodiment.

[0014] Figure 4 Yes Figure 3 The figure obtained by performing equivalent transformation.

[0015] Figure 5 This is a diagram showing the structure of the input device involved in Embodiment 1.

[0016] Figure 6 This is a Bode diagram showing a frequency response from the first deviation suppression signal to the second mechanical end relative displacement of the mechanical device used as a target in the experiment according to the first embodiment.

[0017] Figure 7This is a diagram showing the first position command.

[0018] Figure 8 This is a diagram showing experimental results comparing responses during positioning operation when the motor control device according to the first embodiment is used and when the motor control device is not used.

[0019] Fig. 9 This is a diagram showing a configuration of a system including a motor control device according to a second embodiment.

[0020] Fig.10 This is a diagram showing a processor in the case where at least part of the functions of the first controller, the detector, the second controller, the gantry state estimator, the correction amount determiner, and the calculator included in the motor control device according to the first embodiment are implemented by the processor.

[0021] Fig.11 This is a diagram showing a processing circuit in which at least part of the functions of the first controller, detector, second controller, gantry state estimator, correction amount determiner, and operator of the motor control device according to Embodiment 1 are implemented by the processing circuit. DETAILED DESCRIPTION

[0022] Hereinafter, a motor control device and a mechanical device according to an embodiment will be described in detail with reference to the drawings.

[0023] Implementation method 1.

[0024] Figure 1 is a top view of a mechanical device 100 having two electric motors. Figure 2 is a side view of a mechanical device 100 having two electric motors. Figure 1 and Figure 2 A mechanical device 100 having two electric motors is schematically shown. Figure 1 and Figure 2 The mechanical device 100 shown has a stand 1 supported by a leveling block 8, a first motor 2 and a second motor 3 fixed to the stand 1, a first driving body 4 driven by the first motor 2, and a second driving body 5 driven by the second motor 3. The second motor 3 is a motor different from the first motor 2.

[0025] The gantry 1 includes a gantry lower portion 1c, a gantry side 1a provided on the gantry lower portion 1c, and a gantry upper portion 1b provided on the gantry side 1a. The first motor 2 includes a fixing member 2a fixed to the gantry upper portion 1b and a movable member 2b moving in the length direction of the fixing member 2a. The second motor 3 includes a fixing member 3a fixed to the gantry upper portion 1b and a movable member 3b moving in the length direction of the fixing member 3a. In the first embodiment, the first motor 2 and the second motor 3 are linear motors. The first motor 2 and the second motor 3 are not limited to linear motors, and may also be rotary motors.

[0026] The first driving body 4 includes: a driving part 4a, which is provided on the movable part 2b and operates as a whole with the movable part 2b; and a working tool 4b, which is fixed to the front end of the driving part 4a. The second driving body 5 includes: a driving part 5a, which is provided on the movable part 3b and operates as a whole with the movable part 3b; and a working tool 5b, which is fixed to the front end of the driving part 5a. In embodiment 1, the working tool 4b and the working tool 5b are cutting tools. The working tool 4b and the working tool 5b are not limited to cutting tools, but can also be a robot hand. In embodiment 1, the working tool 4b processes the working object 6 provided on the lower part 1c of the platform, and the working tool 5b processes the working object 7 provided on the lower part 1c of the platform.

[0027] In the first embodiment, a mechanical device having two motors is described as a control target to facilitate understanding of the effects of the motor control device according to the first embodiment. The effects of the motor control device according to the first embodiment can also be obtained for mechanical devices having three or more motors.

[0028] Figure 3 1 is a diagram showing the structure of a system including a motor control device according to Embodiment 1. In Embodiment 1, in order to facilitate understanding of the structure of the system, matters related to the case where the deterioration of the control performance of the second motor 3 caused by the driving of the first motor 2 is suppressed are described. The motor control device according to Embodiment 1 can be applied to the case where the deterioration of the control performance of the first motor 2 caused by the driving of the second motor 3 is suppressed, and the deterioration of the control performance of the second motor 3 caused by the driving of the first motor 2 and the deterioration of the control performance of the first motor 2 caused by the driving of the second motor 3 are suppressed.

[0029] The motor control device according to the first embodiment includes a first motor 2 and a second motor 3 provided on a frame 1. The motor control device according to the first embodiment further includes a first controller 11 for determining a first deviation suppression signal T1, which drives the first motor 2 based on a first position command and a first motor position signal for determining a position of a movable part 2b of the first motor 2 so as to reduce a difference between the first position command and the first motor position signal. The movable part 2b is driven based on the first deviation suppression signal T1. In the first embodiment, the first deviation suppression signal T1 is a reference driving force signal. The motor control device according to the first embodiment further includes a detector 12 for detecting a relative position between the position of the movable part 2b of the first motor 2 and the frame 1, i.e., a relative displacement of the first motor end. The first motor position signal indicates the relative displacement of the first motor end detected by the detector 12. The transfer characteristic H1 from the relative displacement of the first motor end to the first motor position signal is expressed by the following formula (1).

[0030] [Formula 1]

[0031] H1=1 …(1)

[0032] The first controller 11 includes: an operator 11a that outputs a first position deviation signal obtained by subtracting a first motor position signal from a first position instruction; and a proportional gain output device 11b that outputs a first speed correction signal obtained by multiplying the first position deviation signal by Kpp1. The first controller 11 also includes: a differentiator 11c that differentiates the first motor position signal; and an operator 11d that outputs a first speed deviation signal based on the first speed correction signal and a signal obtained by differentiating the first motor position signal by the differentiator 11c. Specifically, the operator 11d subtracts a signal obtained by differentiating the first motor position signal by the differentiator 11c from the first speed correction signal, and outputs the first speed deviation signal. The first controller 11 also includes a first speed controller 11e that outputs a first deviation suppression signal T1 based on the first speed deviation signal. In the first embodiment, the first speed controller 11e is a PI (P: Propotional, I: Integral) controller. Transfer characteristic C of the first speed controller 11e v1 (s) is represented by the following formula (2).

[0033] [Formula 2]

[0034]

[0035] s is the Laplace operator. K vp1 is the proportional gain of speed control, K vi1is the integral gain of the speed control. The transfer characteristic C1(s) from the first motor position signal to the first deviation suppression signal T1 can be expressed by the following equation (3).

[0036] [Formula 3]

[0037]

[0038] In the first embodiment, the first controller 11 is a P-PI controller. The first controller 11 is not limited to the P-PI controller, and may be a PID (Proportional-Integral-Differential) controller.

[0039] The motor control device according to the first embodiment further includes a second controller 13 that determines a second deviation suppression signal, which drives the second motor 3 based on a second position command that determines the position of the movable part 3b of the second motor 3 and a second motor position signal so as to reduce the difference between the second position command and the second motor position signal. Further, the second controller 13 determines a second deviation suppression signal that drives the second motor 3 so as to reduce the difference between a signal based on the second position command that specifies the position of the movable part 3b of the second motor 3 and a second motor position signal that indicates the relative position of the movable part 3b of the second motor 3 and the fixed part 3a of the second motor 3. The motor control device according to the first embodiment further includes a detector 14 that detects the relative position of the movable part 3b of the second motor 3 and the frame 1, that is, the relative displacement of the second motor end. The second motor position signal indicates the relative displacement of the second motor end detected by the detector 14. The transfer characteristic H2 from the second motor end relative displacement to the second motor position signal is expressed by the following equation (4).

[0040] [Formula 4]

[0041] H2=1…(4)

[0042] The second controller 13 includes: an operator 13a, which outputs a second position deviation signal obtained by subtracting the second motor position signal from the second position instruction; and a proportional gain output device 13b, which outputs a second speed correction signal obtained by multiplying the second position deviation signal by Kpp2. The second controller 13 also includes: a differentiator 13c, which differentiates the second motor position signal; and an operator 13d, which outputs a second speed deviation signal based on the second speed correction signal and a signal obtained by the differentiator 13c by differentiating the second motor position signal. Specifically, the operator 13d subtracts the signal obtained by the differentiator 13c by differentiating the second motor position signal from the second speed correction signal, and outputs the second speed deviation signal. The second controller 13 also includes a second speed controller 13e, which outputs a second deviation suppression signal based on the second speed deviation signal. In embodiment 1, the second speed controller 13e is a PI controller, and the transfer characteristic C of the second speed controller 13e is V2 (s) is represented by the following formula (5).

[0043] [Formula 5]

[0044]

[0045] K vp2 is the proportional gain of speed control, K vi2 is the integral gain of the speed control. The transfer characteristic C2(s) from the second motor position signal to the second deviation suppression signal can be expressed by the following equation (6).

[0046] [Formula 6]

[0047]

[0048] In the first embodiment, C2(s) represented by equation (6) is the transfer characteristic of the second controller 13. In the first embodiment, the second controller 13 is a P-PI controller. The second controller 13 is not limited to the P-PI controller, but may be a PID controller.

[0049] The motor control device involved in the first embodiment also has a gantry state estimator 15, which determines an estimated value of the absolute position of the gantry upper part 1b in the gantry 1 that is elastically deformed by the driving reaction force of the movable parts 2b and the movable parts 3b, that is, the gantry model position, based on the first deviation suppression signal T1. Further, the gantry state estimator 15 determines an estimated value of the absolute position of the gantry 1 that is elastically deformed by the driving reaction force of the movable part 2b of the first motor 2, that is, the gantry model position, based on a signal representing the force driving the movable part 2b of the first motor 2, that is, the reference driving force signal. The motor control device involved in the first embodiment also has a correction amount determiner 16A, which determines a displacement correction signal based on the gantry model position determined by the gantry state estimator 15. The transfer characteristic of the gantry state estimator 15 is expressed as G s (s), the transfer characteristic of the correction amount determiner 16A is expressed as G t (s).

[0050] The motor control device according to the first embodiment further includes a calculation unit 17, which determines and outputs a correction motor drive signal for driving the second motor 3 based on the second deviation suppression signal determined by the second controller 13 and the displacement correction signal determined by the correction amount determiner 16A. Specifically, the calculation unit 17 adds the second deviation suppression signal output by the second speed controller 13e and the displacement correction signal determined by the correction amount determiner 16A to output the correction motor drive signal. The movable part 3b of the second motor 3 is driven based on the correction motor drive signal.

[0051] Next, the transfer characteristic G of the rack state estimator 15 is shown. s (s) and the transfer characteristic G of the correction amount determiner 16A t (s) export process.

[0052] P1(s) is a model representing the characteristics from the first deviation suppression signal T1 to the position of the movable part 2b of the first motor 2. P2(s) is a model representing the characteristics from the second deviation suppression signal to the position of the movable part 3b of the second motor 3. If P1(s) and P2(s) are rigid body models, P1(s) can be represented by the following equation (7), and P2(s) can be represented by the following equation (8).

[0053] [Formula 7]

[0054]

[0055] [Formula 8]

[0056]

[0057] m1 is the sum of the mass of the movable element 2 b of the first motor 2 and the mass of the first driving body 4 , and m2 is the sum of the mass of the movable element 3 b of the second motor 3 and the mass of the second driving body 5 .

[0058] P s (s) is a model showing the characteristics from the force applied to the gantry 1 to the position of the gantry upper part 1b. The force applied to the gantry 1 here is the reaction force generated by the driving of the first motor 2 and the second motor 3. If the first motor 2 and the second motor 3 are driven, the reaction force generated by the driving is transmitted to the gantry 1, and the gantry 1 is elastically deformed due to the reduction of the rigidity of the gantry 1. If the displacement of the gantry 1 is modeled by a spring mass damper, P s (s) can be expressed by the following formula (9).

[0059] [Formula 9]

[0060]

[0061] K b is the spring constant, D b is the attenuation coefficient, M b is the mass of the stand 1. As shown in equation (9), the transfer function of the stand 1 is represented by a second-order vibration system. The model of the stand 1 represented by equation (9) is assumed to include resonance characteristics, and the poles of equation (9) become complex numbers. As described above, the model of the stand 1 is represented by a second-order vibration system, thereby being able to model the stand 1 including the resonance characteristics of the stand 1. Here, in embodiment 1, the transfer function of the stand 1 is represented by the second order for simplicity, but in order to represent complex vibration characteristics, it can also be modeled by greater than or equal to the third order.

[0062] Here, the stand 1 is assumed to vibrate in a locked mode. When the stand 1 vibrates in a locked mode, the stand 1 vibrates while rotating around the leveling block 8. At this time, the stand upper portion 1b and the stand lower portion 1c are modeled to vibrate at the same frequency, the same phase, and different amplitudes. The position x of the stand upper portion 1b is u The position x of the lower part 1c of the platform can be expressed by the following equation (10): d It can be expressed by the following formula (11).

[0063] [Formula 10]

[0064] x u =Ae ζt cos(ωt+α)…(10)

[0065] [Formula 11]

[0066] xd =Be ζt cos(ωt+α)…(11)

[0067] A is the maximum amplitude of the upper part 1b of the platform, B is the maximum amplitude of the lower part 1c of the platform, ζ is the attenuation ratio, t is the time, ω is the natural angular vibration frequency, and α is the initial phase. That is, the position x of the lower part 1c of the platform d By using the position x of the upper part 1b of the platform u The platform vibration amplitude ratio P is the ratio of the maximum amplitude B of the lower part 1c to the maximum amplitude A of the upper part 1b of the platform. k =B / A, which can be expressed as the following formula (12).

[0068] [Formula 12]

[0069]

[0070] exist Figure 3 In the example, the first deviation suppression signal T1 is used to obtain the second mechanical end relative displacement x obtained by subtracting the position of the lower part 1c of the platform from the position of the movable member 3b of the second motor 3. tip The transfer function up to can be expressed by the following equation (13): wherein H1=1 and H2=1 are substituted.

[0071] [Formula 13]

[0072]

[0073] From equation (13), we get the following equation (14). According to equation (14), in order to make the second mechanical end relatively displace x tip To achieve zero, the following equation (15) can be satisfied.

[0074] [Formula 14]

[0075]

[0076] [Formula 15]

[0077]

[0078] By substituting equations (7), (8) and (9) into equation (15), the following equation (16) is obtained.

[0079] [Formula 16]

[0080]

[0081] Generally, the mass of the gantry 1 is sufficiently larger than the sum of the mass of the movable element 3 b and the mass of the second driving body 5 , so the following equation (17) is obtained. The equation (17) is an approximate equation.

[0082] [Formula 17]

[0083]

[0084] Platform vibration amplitude ratio P k Generally speaking, 0≤Pk≤1, so the following equation (18) is obtained. Equation (18) is an approximate equation.

[0085] [Formula 18]

[0086]

[0087] By substituting equation (17) and equation (18) into equation (16), equation (19) can be obtained.

[0088] [Formula 19]

[0089]

[0090] G s (s) is represented by the following formula (20), G t (s) is represented by the following formula (21).

[0091] [Formula 20]

[0092]

[0093] [Formula 21]

[0094] G t (s)=-(1-P k )C2(s)-P k m2s 2 …(twenty one)

[0095] G s (s) and P s (s) is consistent, so we know that G s (s) is a transfer function of the model of the rack 1. That is, the rack state estimator 15 estimates the position of the rack 1 based on the first deviation suppression signal T1. The rack state estimator 15 is a second-order vibration system in Embodiment 1, so the rack state estimator 15 can calculate the rack model position including the resonance characteristics of the rack 1. Therefore, the rack state estimator 15 can include the resonance characteristics of the rack 1 and perform non-interference. In addition, when the rack 1 is modeled at a third order or greater, the rack state estimator 15 is greater than or equal to the third order. As described above, the rack state estimator 15 performs a calculation represented by a transfer function including a second-order vibration system.

[0096] If the attenuation ratio of stand 1 is set to ζ n, the natural angular vibration frequency of the platform 1 is set to ω n , then formula (20) can also be expressed as the following formula (22).

[0097] [Formula 22]

[0098]

[0099] The characteristics of the gantry state estimator 15 are based on the mass M of the gantry 1 in equation (20): b , Viscous friction coefficient D b and spring constant K b , the natural angular frequency ω in formula (22) n and attenuation ratio ζ n And be determined. n In order to express the resonance of the gantry 1, the value of ζn may be set to a value greater than or equal to 0 and less than 1. The characteristics of the correction amount determiner 16A are based on the transfer characteristic C2(s) of the second controller 13, the gantry vibration amplitude ratio P k It is determined by the sum of the mass force of the movable element 3 b of the second motor 3 and the mass of the second driving body 5 , that is, m2.

[0100] In the first embodiment, a block diagram showing the configuration of a system including a motor control device is Figure 3 , but the block diagram showing the structure of the system including the motor control device according to the first embodiment is not limited to Figure 3 , which can be from Figure 3 The graph obtained by performing equivalent transformation. For example Figure 4 Yes Figure 3 The figure obtained by performing equivalent transformation. Figure 4 The motor control device shown can obtain Figure 1 The motor control device shown has the same effect.

[0101] exist Figure 4 In the system shown, Figure 3 The operator 13d is replaced by the operator 13d1. Figure 4 The system shown has a position displacement corrector 18 and a velocity displacement corrector 19. The transfer characteristic of the position displacement corrector 18 is the same as the transfer characteristic of the velocity displacement corrector 19. The transfer characteristics G of the position displacement corrector 18 and the velocity displacement corrector 19 are p It is represented by the following formula (23).

[0102] [Formula 23]

[0103] G p =1-P k …(twenty three)

[0104] Figure 4The motor control device shown in the figure has a correction amount determiner 16B. The transfer characteristic G of the correction amount determiner 16B is τ It is represented by the following formula (24).

[0105] [Formula 24]

[0106] G r =-P k m2s 2 …(twenty four)

[0107] Figure 4 G s (s) and Figure 3 G s (s) are the same. Figure 4 In the embodiment, the position displacement corrector 18 outputs a position correction signal to the operator 13a1 based on the gantry model position. The operator 13a1 outputs a second position deviation signal based on the position correction signal, the second position command and the second motor position signal. The speed displacement corrector 19 outputs a speed correction signal to the operator 13d1 based on the gantry model speed obtained by differentiating the gantry model position by the differentiator 20. The operator 13d1 outputs a second speed deviation signal based on the second speed correction signal, the speed correction signal and the signal obtained by differentiating the motor position signal by the differentiator 13c. Figure 4 Other structures in Figure 1 same.

[0108] Figure 3 The gantry state estimator 15 and the correction amount determiner 16A, and Figure 4 The parameters included in the gantry state estimator 15, the correction amount determiner 16B, the position displacement corrector 18 and the speed displacement corrector 19 are obtained from Figure 5 The input device 31 shown is input. Figure 5 1 is a diagram showing the structure of the input device 31 according to Embodiment 1. The input device 31 is a computer having a processor 31a, a storage device 31b, and an input unit 31c. The storage device 31b is implemented by, for example, a semiconductor memory. In Embodiment 1, the input unit 31c is an input key. The input unit 31c is not limited to an input key.

[0109] In the right Figure 3 The gantry state estimator 15 and the correction amount determiner 16A, and Figure 4When the parameters included in the gantry state estimator 15, the correction amount determiner 16B, the position displacement corrector 18, and the speed displacement corrector 19 are changed, the user assigns the value of the parameter to be changed using the input unit 31c to the input device 31. The processor 31a changes the value of the parameter to be changed to the value assigned by the input unit 31c. The storage device 31b can store a plurality of different parameters. The processor 31a can read the parameters stored in the storage device 31b and change the value of the parameter to be changed.

[0110] The effect of suppressing the degradation of the control performance of the second electric motor 3 by driving the first electric motor 2 was confirmed through experiments. Figure 6 This is a Bode plot showing the frequency response from the first deviation suppression signal to the second machine end relative displacement of the machine device used as the object in the experiment according to Embodiment 1. In the frequency response from the first deviation suppression signal to the second machine end relative displacement, resonances exist around 25 Hz and around 90 Hz.

[0111] use Figure 7 and Figure 8 , a diagram illustrating experimental results of comparing responses during positioning operation when the motor control device according to Embodiment 1 is used and when the motor control device is not used. Figure 7 This is a diagram showing the first position command. Figure 8 This is a diagram showing experimental results comparing responses during positioning operation when the motor control device according to the first embodiment is used and when the motor control device is not used.

[0112] Figure 8 The relative displacement of the second mechanical end when the first driving body 4 is driven by the first position command is shown. Figure 8 The solid line shows the result when the motor control device according to the first embodiment is not used for non-interference. Figure 8 The dashed line in shows the result when the motor control device according to the first embodiment performs non-interference. Figure 8In the figure, the solid line is appended with the statement "the technology of the present application is not applied" indicating that the motor control device involved in the first embodiment is not non-interfered, and the dot-dash line is appended with the statement "the technology of the present application is applied" indicating that the motor control device involved in the first embodiment is non-interfered. In this experiment, from the start of the experiment to about 50ms, the first position command is zero, and the first motor 2 and the second motor 3 are stationary. During the experimental elapsed time of about 50ms to about 280ms, the first position command gradually increases and reaches 0.3m. After the elapsed time reaches about 280ms, the first position command becomes a stable value of 0.3m. The second position command is zero from the start of the experiment to the end of the experiment.

[0113] according to Figure 8 It is clear that the motor control device according to the first embodiment performs non-interference, thereby particularly being able to suppress the relative displacement of the second mechanical end during acceleration and deceleration of the first motor 2, confirming the non-interference effect obtained by the motor control device according to the first embodiment.

[0114] As described above, the motor control device according to the first embodiment can suppress the degradation of the control performance of one of the two motors caused by driving the other motor. Figure 3 The gantry state estimator 15 and the correction amount determiner 16A, and Figure 4 The gantry state estimator 15, the position displacement corrector 18, the speed displacement corrector 19, and the correction amount determiner 16B, that is, the parameters included in the compensator for non-interference of the influences between the axes have physical meanings, so the motor control device involved in the first embodiment can determine the characteristics of the compensator for non-interference of the influences between the axes in a short time. That is, the motor control device involved in the first embodiment can suppress the interference between the axes and can adjust the compensator for non-interference of the influences between the axes in a short time.

[0115] Furthermore, the gantry state estimator 15 determines the gantry model position based on at least any one of the attenuation ratio of the gantry 1 , the attenuation coefficient of the gantry 1 , the natural angular vibration frequency of the gantry 1 , the spring constant of the gantry 1 , and the mass of the gantry 1 .

[0116] The correction amount determiner 16A determines the displacement correction signal based on at least any one of the mass of the second driving body 5 driven by the second motor 3, the moment of inertia of the second driving body 5, the mass of the movable part 3b of the second motor 3, the moment of inertia of the movable part 3b of the second motor 3, the transfer characteristics of the second controller 13, and the amplitude ratio of the vibration at two points of the platform 1, that is, the platform vibration amplitude ratio.

[0117] A signal representing the force for driving the movable part 2b of the first motor 2, i.e., a reference driving force signal; a first model driving force, i.e., an ideal driving force for causing the position of the movable part 2b of the first motor 2 to follow a signal based on a first position instruction that determines the position of the first motor 2; a first deviation suppression signal, i.e., a signal for driving the movable part 2b of the first motor 2 so that the difference between the signal based on the first position instruction and the first motor position signal becomes smaller; and a first motor driving signal calculated based on the first model driving force and the first deviation suppression signal.

[0118] Implementation method 2.

[0119] Fig. 9 1 is a diagram showing the structure of a system including a motor control device according to Embodiment 2. In Embodiment 2, a first feedforward compensator 21 for performing a first feedforward compensation is added to the first controller 11 in Embodiment 1, and a second feedforward compensator 22 for performing a second feedforward compensation is added to the second controller 13 in Embodiment 1. That is, the motor control device according to Embodiment 2 includes: a first controller 11 including a first feedback controller 11F and a first feedforward compensator 21; and a second controller 13 including a second feedback controller 13F and a second feedforward compensator 22. An operator 23 is also added. In addition, a gantry state estimator 15A is different from the gantry state estimator 15 in Embodiment 1 in that it estimates the gantry model position based on the first model driving force, which is one of the outputs of the first feedforward compensator 21. In Embodiment 2, description of the same parts as those in Embodiment 1 is omitted.

[0120] In the second embodiment, as described above, the first controller 11 includes the first feedforward compensator 21 and the first feedback controller 11F. The first feedforward compensator 21 calculates the first model position, the first model speed, and the first model driving force based on the first position command, and outputs the calculation result to the first feedback controller 11F. In the second embodiment, the first model driving force is a reference driving force signal. The reference driving force signal is not limited to the first model driving force, but may also be the sum of the first model driving force and the first deviation suppression signal, that is, the first motor driving signal.

[0121] The first model position is determined based on the first position command and the low-pass filter 21a that attenuates high-frequency components. The transfer characteristic of the low-pass filter 21a is represented by C f1(s). In the second embodiment, the low-pass filter 21a is a first-order low-pass filter. The low-pass filter 21a is not limited to a low-pass filter. The first model velocity is determined based on the first model position and the differentiator 21b that performs a differential operation. The first model driving force is a result obtained by multiplying the value obtained by differentiating the first model velocity by the differentiator 21c by the proportional gain 21d. The proportional gain 21d sets the input signal to m1 times. m1 is the sum of the mass of the first driving body 4 and the mass of the movable part 2b.

[0122] The first feedback controller 11F determines the first deviation suppression signal based on the first model position and the first motor position signal. The operator 11a2 subtracts the first motor position signal from the first model position and outputs the first position deviation signal. The operator 11d2 outputs the first speed deviation signal based on the first model speed, the first speed correction signal and the signal obtained by differentiating the first motor position signal.

[0123] The calculation unit 23 outputs a first motor drive signal based on the first deviation suppression signal and the first model drive force. The movable element 2b is driven based on the first motor drive signal.

[0124] As described above, the second controller 13 includes the second feedforward compensator 22 and the second feedback controller 13F. The second feedforward compensator 22 calculates the second model position, the second model speed, and the second model driving force based on the second position command, and outputs the calculation result to the second feedback controller 13F. The second model position is determined based on the second position command and the low-pass filter 22a that attenuates high-frequency components. The transfer characteristic of the low-pass filter 22a is expressed as C f2 (s) In Embodiment 2, the low-pass filter 22a is a first-order low-pass filter. The low-pass filter 22a is not limited to a first-order low-pass filter.

[0125] The second model speed is determined based on the second model position and the differentiator 22b that performs differential operation. The second model driving force is the result of multiplying the value obtained by differentiating the second model speed by the differentiator 22c by the proportional gain 22d. The proportional gain 22d multiplies the input signal by m2. m2 is the sum of the mass of the movable part 3b of the second motor 3 and the mass of the second driving body 5.

[0126] The second feedback controller 13F determines the second deviation suppression signal based on the second model position and the second motor position signal. The operator 13a2 subtracts the second motor position signal from the second model position and outputs the second position deviation signal. The operator 13d2 outputs the second speed deviation signal based on the second model speed, the second speed correction signal and the signal obtained by differentiating the second motor position signal.

[0127] The transfer characteristic of the second controller 13 in the second embodiment is a transfer characteristic from the second motor position signal to the second deviation suppression signal, and is expressed by equation (6).

[0128] The calculation unit 17A determines the correction motor drive signal based on the second deviation suppression signal, the second model drive force, and the displacement correction signal. The movable element 3b is driven based on the correction motor drive signal.

[0129] Note that the diagram showing the configuration of a system including the motor control device according to the second embodiment is not limited to Fig. 9 , or Fig. 9 The equivalent transformed graph.

[0130] As described above, according to the motor control device involved in embodiment 2, the gantry model position is estimated based on the first model driving force and the gantry state estimator 15A, and the displacement correction signal is determined based on the gantry model position and the correction amount determiner 16A, thereby obtaining the effect that the influence of the noise contained in the detector 12 is not included in the displacement correction signal.

[0131] Fig.10 This is a diagram of processor 91 in a case where at least a part of the functions of the first controller 11, detector 12, second controller 13, detector 14, gantry state estimator 15, correction amount determiner 16A, and operator 17 of the motor control device involved in embodiment 1 are implemented by processor 91. That is, at least a part of the functions of the first controller 11, detector 12, second controller 13, detector 14, gantry state estimator 15, correction amount determiner 16A, and operator 17 can be implemented by processor 91 executing a program stored in memory 92. Processor 91 is a CPU (Central Processing Unit), a processing system, an operation system, a microprocessor, or a DSP (Digital Signal Processor). Fig.10 A memory 92 is also shown.

[0132] When at least a part of the functions of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the calculator 17 are implemented by the processor 91, the at least part of the functions are implemented by the processor 91 and software, firmware, or a combination of software and firmware. The software or firmware is described as a program and stored in the memory 92. The processor 91 reads out the program stored in the memory 92 and executes it, thereby implementing at least a part of the functions of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the calculator 17.

[0133] When at least a part of the functions of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the computing unit 17 are realized by the processor 91, the motor control device according to the first embodiment includes a memory 92 for storing a program that finally executes at least a part of the steps executed by the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the computing unit 17. The program stored in the memory 92 can be said to cause a computer to execute at least a part of the procedure or method executed by the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the computing unit 17.

[0134] The memory 92 is, for example, a nonvolatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (registered trademark) (Electrically Erasable Programmable Read-Only Memory), a magnetic disk, a floppy disk, an optical disk, a compact disk, a mini disk, or a DVD (Digital Versatile Disk).

[0135] Fig.11 This is a diagram showing a processing circuit 93 in a case where at least a part of the functions of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the calculator 17 included in the motor control device according to the first embodiment are implemented by the processing circuit 93. That is, at least a part of the functions of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the calculator 17 can be implemented by the processing circuit 93.

[0136] The processing circuit 93 is dedicated hardware and is, for example, a single circuit, a complex circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof.

[0137] The functions of part of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A and the operator 17 can be implemented by dedicated hardware that is different from the hardware that implements the functions of the remaining parts of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A and the operator 17 possessed by the motor control device.

[0138] Regarding the multiple functions of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the calculator 17, a part of the multiple functions may be realized by software or firmware, and the rest of the multiple functions may be realized by dedicated hardware. As described above, the multiple functions of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15, the correction amount determiner 16A, and the calculator 17 can be realized by hardware, software, firmware, or a combination thereof.

[0139] Figure 4 At least a part of the functions of the arithmetic unit 11a, proportional gain output unit 11b, differentiator 11c, arithmetic unit 11d, first speed controller 11e, detector 12, arithmetic unit 13a1, proportional gain output unit 13b, differentiator 13c, arithmetic unit 13d1, second speed controller 13e, detector 14, platform state estimator 15, correction amount determiner 16B, arithmetic unit 17, position displacement corrector 18, speed displacement corrector 19 and differentiator 20 shown in the figure can be realized by a processor executing a program stored in a memory or by a processing circuit. The memory is a memory equivalent to the memory 92, the processor is a processor equivalent to the processor 91, and the processing circuit is a processing circuit equivalent to the processing circuit 93.

[0140] Fig. 9 At least a part of the functions of the first controller 11, the detector 12, the second controller 13, the detector 14, the gantry state estimator 15A, the correction amount determiner 16A, and the calculator 17A shown in the figure may be realized by a processor that executes a program stored in a memory, or may be realized by a processing circuit. The memory is a memory equivalent to the memory 92, the processor is a processor equivalent to the processor 91, and the processing circuit is a processing circuit equivalent to the processing circuit 93.

[0141] The structure shown in the above embodiment is just an example, and it is possible to combine with other well-known technologies, and it is possible to combine the embodiments with each other. It is also possible to omit or change a part of the structure without departing from the scope of the subject matter.

[0142] Description of the label

[0143] 1 platform, 1a platform side, 1b platform upper part, 1c platform lower part, 2 first motor, 2a, 3a fixed parts, 2b, 3b movable parts, 3 second motor, 4 first driving body, 4a, 5a driving part, 4b, 5b working tool, 5 second driving body, 6, 7 working object, 8 leveling block, 11 first controller, 11a, 11a2, 11d, 11d2, 13a, 13a1, 13a2, 13d, 13d1, 13d2, 17, 17A, 23 computing unit, 11b, 13b proportional gain output device, 11c, 13c, 20, 21b, 21c, 22b, 22 c differentiator, 11e first speed controller, 11F first feedback controller, 12, 14 detectors, 13 second controller, 13e second speed controller, 13F second feedback controller, 15, 15A platform state estimator, 16A, 16B correction amount determiner, 18 position displacement corrector, 19 speed displacement corrector, 21 first feedforward compensator, 21a, 22a low-pass filter, 21d, 22d proportional gain, 22 second feedforward compensator, 31 input device, 31a, 91 processors, 31b storage device, 31c input unit, 92 memory, 93 processing circuit, 100 mechanical device.

Claims

1. A motor control device, characterized in that: have: a first motor disposed on a stand; a second motor, which is disposed on the frame and is different from the first motor; a second controller for determining a second deviation suppression signal, the second deviation suppression signal being a signal for driving the second motor so that a difference between a signal based on a second position instruction specifying a position of a movable member of the second motor and a second motor position signal indicating a relative position of the movable member of the second motor and a fixed member of the second motor becomes smaller; a stage state estimator that determines a stage model position, which is an estimated value of the absolute position of the stage elastically deformed by a reaction force of the driving of the movable member of the first motor, based on a reference driving force signal that is a signal indicating a force driving the movable member of the first motor; a correction amount determiner that determines a displacement correction signal based on the gantry model position determined by the gantry state estimator; and A calculation unit determines a correction motor drive signal for driving the second motor based on the displacement correction signal determined by the correction amount determiner and the second deviation suppression signal determined by the second controller.

2. The motor control device according to claim 1, characterized in that: The platform state estimator performs calculations represented by a transfer function including a second-order vibration system.

3. The motor control device according to claim 1, characterized in that: The gantry state estimator determines the gantry model position based on at least any one of an attenuation ratio of the gantry, an attenuation coefficient of the gantry, a natural angular vibration frequency of the gantry, a spring constant of the gantry, and a mass of the gantry.

4. The motor control device according to claim 1, characterized in that: The correction amount determiner determines the displacement correction signal based on at least any one of the mass of the second driving body driven by the second motor, the moment of inertia of the second driving body, the mass of the movable part of the second motor, the moment of inertia of the movable part of the second motor, the transfer characteristics of the second controller, and the amplitude ratio of the vibration at two points of the platform, i.e., the platform vibration amplitude ratio.

5. The motor control device according to claim 1, characterized in that: The reference driving force signal is any one of an ideal driving force, i.e., a first model driving force, for causing the position of the movable part of the first motor to follow a signal based on a first position instruction that determines the position of the first motor; a first deviation suppression signal, i.e., a signal for driving the movable part of the first motor so that the difference between the signal based on the first position instruction and the first motor position signal becomes smaller; and a first motor driving signal calculated based on the first model driving force and the first deviation suppression signal.

6. A mechanical device, characterized in that: have: Electric motor; A stand for holding the motor; The motor control device according to any one of claims 1 to 4 controls the motor.

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