CN102122913A - Controller for hyperfine stepping motor - Google Patents
Controller for hyperfine stepping motor Download PDFInfo
- Publication number
- CN102122913A CN102122913A CN 201110066238 CN201110066238A CN102122913A CN 102122913 A CN102122913 A CN 102122913A CN 201110066238 CN201110066238 CN 201110066238 CN 201110066238 A CN201110066238 A CN 201110066238A CN 102122913 A CN102122913 A CN 102122913A
- Authority
- CN
- China
- Prior art keywords
- control
- stepping motor
- module
- hyperfine
- speed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Abstract
The invention discloses a controller for a hyperfine stepping motor, which comprises an external communication interface, a control signal generator and a stepping motor driver, wherein the control signal generator comprises a programmable logic device chip and a first power supply circuit, and the stepping motor driver comprises a receiving port, an output port and a second power supply circuit used for providing a driving current. By using the controller for a hyperfine stepping motor, the hyperfine speed regulation for the stepping motor is realized while the controller runs at a high speed under high subdivision condition, the starting and stopping speed is increased, the starting torque is increased and the application scope of the stepping motor is expanded.
Description
Technical field
The invention belongs to electric machines control technology, particularly a kind of hyperfine Stepping Motor Control device.
Background technology
Stepping motor is a kind of discrete telecontrol equipment, the every field that is widely used in national economy, the general purpose control method is to adopt single-chip microcomputer to control in conjunction with the method for controllor for step-by-step motor at present, the shortcoming of this control method is: 1, because the restriction of the speed of service of single-chip microcomputer, when realizing that segmentation drives, stepper motor speed is not high.2, single-chip microcomputer is by the generation of the step-by-step impulse of timer control step motor, because the temporal resolution of timer is limited, so the speed of service of stepping motor is regulated and is dispersed, bigger at interval between each step velocity, can not meet the demands in some occasions to the rate request strictness.3, because the interval of speed is bigger, cause the moment between each speed also discontinuous, step-out takes place easily.So stepping motor can only be used for simple control system.
Summary of the invention
The object of the invention is to overcome above-mentioned the deficiencies in the prior art, the invention provides a kind of hyperfine Stepping Motor Control device, speed and step number that can hyperfine control step machine.
For achieving the above object, technical scheme of the present invention is as follows:
A kind of hyperfine Stepping Motor Control device comprises external communication interface, control-signals generator, stepper motor driver, and characteristics are that described control-signals generator comprises the programmable logic device chip and first power supply circuits thereof; This programmable logic device chip comprises rate control module, decoder module, clock module, and the main control module, flash control module and the memory module that connect successively, this programmable logic device chip also comprises the output interface that is used to receive the receiving port of external control instruction and Control Parameter is changed into control signal, described control-signals generator also has the control interface agreement that is used to receive the external control instruction, meticulous speed governing algorithm and Precision Orientation Algorithm;
Described stepper motor driver comprises receiving port and output port and is used to provide second power supply circuits of drive current, described receiving port links to each other with the output port of described control-signals generator, and described output port connects described Stepping Motor Control port and links to each other.
Described decoder module is used to receive the control command that peripheral control unit that the receiving port of described control-signals generator receives is sent, and decoding obtains target velocity, target direction and target step number and imports described main control module.
Described main control module is used for speed, direction, position that described target velocity, target direction and target location and stepping motor is current and compares, obtain the running state parameter of described stepping motor as calculated: comprise the speed of service, direction, and reach described target location by the running state parameter execution.
Described rate control module is used for the storage speed change curve, and the speed of service of control motor changes.
Described clock module is used to produce the fractional frequency signal of described control-signals generator needs.
Described flash control module is used for reading control data from described memory module, and to change this control data be to export to described motor drive module behind the suitable data format.
Described memory module is used to store the drive control data of stepping motor.
Described control-signals generator adopts the EMP570 chip.
Described stepper motor driver adopts integrated chip A3973.
Compared with prior art, the invention has the beneficial effects as follows at the high-speed cruising of realizing under the high segmentation situation, realize the superfine speed governing of stepping motor simultaneously, improve and start and stop speed, improve staring torque, and can expand the range of application of stepping motor greatly, as require control occasion of rapid starting/stopping etc.
Description of drawings
Fig. 1 is the structural representation of the hyperfine Stepping Motor Control device of the present invention.
Fig. 2 is the PERCOM peripheral communication sequential chart of the hyperfine controllor for step-by-step motor of the present invention.
Fig. 3 is the motor drive ic A3973 control timing figure of the hyperfine controllor for step-by-step motor of the present invention.
Fig. 4 is motor-drive circuit figure of the present invention.
Fig. 5 is control signal transmitter internal process figure in the hyperfine controllor for step-by-step motor of the present invention.
Fig. 6 is a control-signals generator decoder module structural representation of the present invention.
Fig. 7 is a control-signals generator clock generation modular structure schematic diagram of the present invention.
Fig. 8 is stepping motor Principle of sub-division figure of the present invention.
Table 1 is a hyperfine controllor for step-by-step motor external communication protocol of the present invention.
Table 2 is step motor drive chip A3973 control protocols of the present invention.
Table 3 is DAC parameter lists.
Table 4 is parameter lists of stepping motor
Embodiment
The invention will be further described below in conjunction with the drawings and specific embodiments, but do not limit protection scope of the present invention with this.
Please consult Fig. 1 earlier, Fig. 1 is the structural representation of the hyperfine Stepping Motor Control device of the present invention.As shown in the figure, a kind of hyperfine Stepping Motor Control device comprises external communication interface, control-signals generator, stepper motor driver, and described control-signals generator comprises the programmable logic device chip and first power supply circuits thereof; This programmable logic device chip comprises rate control module 1, decoder module 2, clock module 3, and the main control module 4, flash control module 5 and the memory module 6 that connect successively, this programmable logic device chip also comprises the output interface that is used to receive the receiving port of external control instruction and Control Parameter is changed into control signal, described control-signals generator also has the control interface agreement that is used to receive the external control instruction, meticulous speed governing algorithm and Precision Orientation Algorithm;
Described stepper motor driver comprises receiving port and output port and is used to provide second power supply circuits of drive current, described receiving port links to each other with the output port of described control-signals generator, and described output port connects described Stepping Motor Control port and links to each other.
The course of work of the present invention: peripheral control unit (single-chip microcomputer for example, ARM, DSP etc.) carry out communication by the external communication interface of hyperfine controllor for step-by-step motor, shown in the PERCOM peripheral communication sequential chart and the hyperfine controllor for step-by-step motor external communication protocol of table 1 the present invention of the hyperfine controllor for step-by-step motor of Fig. 2 the present invention, hyperfine controllor for step-by-step motor receives the motion command of stepping motor, through decoding, obtain target velocity, target direction or the target step number of stepping motor.Then according to the operation of target velocity, target direction or target step number control step motor.
Stepper motor driver adopts integrated chip A3973, and integrated two 6 D/A of this chip internal can accurately realize 32 segmentations.The control timing of this chip is shown in the motor drive ic A3973 control timing figure of the hyperfine controllor for step-by-step motor of Fig. 3 the present invention, control protocol is shown in table 2 step motor drive chip of the present invention A3973 control protocol, and power unit is shown in Fig. 4 motor-drive circuit figure of the present invention.
For reaching the purpose of meticulous control, hyperfine controllor for step-by-step motor adopts 32 segmentation drive stepping motor.Two groups of electric current outputs of A3973 directly link to each other with two windings of stepping motor, for stepping motor provides drive current, inner integrated two digital to analog converters (DAC) of A3973, DAC is according to the size of input data, control A3973 is to the winding output corresponding driving electric current of stepping motor.The control data of A3973 is provided by control-signals generator, by strobe, and clk, three pin inputs of data.The A3973 control data is through detailed test, make very uniform and stable of stepping motor segmentation step pitch, be convenient control, with the control data of A3972 according to the agreement shown in the table 2, be compiled into form with the operation characteristic of stepping motor, data during according to the operation of stepping motor electric current change sequence arrangement, only need be during use according to the traffic direction of stepping motor, read the control data of A3973 successively according to different orders, and be input to A3973 according to sequential shown in Figure 3 and get final product, control signal is stored in the inside FLASH memory module 5 in the control-signals generator.
Control-signals generator is according to the order of external piloting control system device, process calculates the size and the variation tendency of the drive current of stepping motor, and according to the storage mode of size, variation tendency and the A3973 control data of the drive current of stepping motor, produce the address of reading of corresponding FLASH module 5, read the A3973 control data, convert control signal corresponding to.Output to the control interface of A3973, A3973 produces the corresponding driving electric current according to the control data of control-signals generator input, and drive stepping motor is made corresponding action.
When the drive current of step motor drive chip A3973 changes once, stepping motor just moves a step, and direction is by the sense of current decision of two windings of stepping motor.The change speed of motor drive ic A3973 drive current has determined the speed of stepping motor.The drive current change of motor drive ic A3973 is to be caused by the control data that control-signals generator is exported, control data of the every change of control-signals generator, and the drive current of A3973 just changes once.Change the speed of control-signals generator output control number, just changed the speed of service of stepping motor.
Fig. 5 is control signal transmitter internal process figure in the hyperfine controllor for step-by-step motor of the present invention, and as shown in the figure, the course of work of control-signals generator is as follows:
Control-signals generator adopts the EPM570 chip of ALTERA company, and this chip is CPLD (field programmable gate array), its function of flexible configuration as required, and programming language adopts VHDL language.Inside comprises: rate control module 1, decoder module 2, clock module 3, main control module 4, FLASH control module 5, memory module 6.
Clock module 3 is a clock generating circuit shown in Fig. 7 control-signals generator clock of the present invention generation modular structure schematic diagram, according to the clock signal of clk input, produces the fractional frequency signal that controller needs.
FLASH module 5 is read control data from memory module 6, and converts them to the suitable data form, exports to motor driver.
Memory module 6 adopts the inner integrated FLASH memory of EP3C16, is used to store the drive control data of stepping motor.
Master control module 4 is cores of entire controller, receives target velocity and target location that deciphering module 2 passes over.Obtain the memory address of control corresponding data in memory module 6.
Stepping motor segmentation control algolithm is described as follows:
(1) movement angle of stepping motor is determined
Stepping motor rotates corresponding mechanical angle according to the variation of biphase current.
f
el＝(n/4)·f
mech……………………………………………….(1)
Wherein, f
ElBe electrical degree, n is the rotate a circle step number of (360 °) synchronizing operation of electrical degree, f
MechMechanical angle.Biphase current is respectively I
A, I
Bf
ElBe exactly I
A, I
BSynthetic electrical degree.Work as I
A, I
BWhen connecting respectively or turn-offing.Specified mechanical angle of stepping motor operation, this specified mechanical angle are exactly a synchronizing operation mechanical angle.Shown in Fig. 8 stepping motor Principle of sub-division of the present invention figure, this is 90 ° of electrical degree operations, is positioned on the reference axis of electrical degree coordinate.
I
A, I
BVariation and the relation between the electrical degree as shown in Equation 2
I
A＝I
Peak·sin(f
s)，I
B＝I
Peak·cos(f
s)…………………….(2)
F wherein
sBe I
A, I
BSynthetic electrical degree.
Work as f
sBe not positioned on the reference axis, but during certain electrical degree between two reference axis, according to formula 1, mechanical angle also no longer is positioned at the synchronizing position, but is positioned at certain position in the middle of the synchronizing position.Adjust I
A, I
BSize, obtain different f
sValue just can make the mechanical angle motion of stepping motor less than the synchronizing operation angle.Reach the effect of subdividing running.
Computing formula according to the A3973 output current:
I
TRIP＝V
DAC/(Range?x?R
S)…………………….(3)
V
DAC＝[(1+DAC)x?V
REF]/64…………………….(4)
V
DACOutput voltage for A3973 internal digital analog converter.I
TRIPBe the electric current of A3973 output, size is by inner parameter DAC control, changes the value of DAC, just can be according to the size of the communication sequence change A3973 output current of A3973, the segmentation of realization stepping motor.Change I
A, I
BChange direction just can change the change direction of electrical degree, and then change the traffic direction of motor.Be convenient control, the value of DAC is compiled into form, exist in the memory module 6.Because the DAC in the described stepper motor driver has only 6 dimensions, have only 64 to change numerical value exactly, in order to guarantee subdivision accuracy, can only get wherein 32 effective numerical value of conduct, therefore can only accomplish accurate 32 segmentation.
The value of described DAC is compiled into form shown in table 3 DAC parameter list of the present invention, and this table is for existing in the memory module 6 I
A, I
BIt is zero memory headroom that DAC value when all equalling zero is stored in the address.The memory address that changes the DAC data when counterclockwise increasing according to electrical degree shown in Figure 8 increases.Main control module 4 reads the numerical value of memory module 6 successively, and converts the data format that is fit to the A3973 requirement to by the FLASH control module, and exports the A3973 of institute input to by main control module 4 controls.
(2) traffic direction of stepping motor is determined
When main control module 4 read numerical value in the memory module 6 successively, the increase and decrease of reading the address by control store module 6 changed I
A, I
BIncrease and decrease change the traffic direction of motor.
Speed governing algorithm: the algorithm when carrying out speed-regulating function.
Step motor drive chip A3973 changes the output current size according to the value of input DAC, and main control module 4 changes the speed of service of stepping motor by the pace of change of the DAC of control A3973.For guaranteeing the even running of stepping motor, when speed governing, to avoid losing the present of step, the change of speed will guarantee steadily.The steady method of adjustment of speed is speed to be divided into 32 grades, all speed class of traversal present speed and target velocity when speed is adjusted.For guaranteeing the steady of moment, the different step number of each velocity stage operation.Velocity stage and corresponding operation step number establishment form.According to the control protocol of described A3973, the output current that changes A3973 need transmit the data of 16 bit.A3973 communication highest frequency is 5Mhz.Calculate according to master clock 33MHz, the communication frequency of setting described step motor drive chip A3973 is 33/4=4.125MHz.Then control A3973 at every turn and need 16/4.125=1.45us.Corresponding clock frequency is 0.6875MHz.Among the design with 0.6875MHz as the Stepping Motor Control clock.0.6875MHz is carried out frequency division, can realize different speed class, the concrete velocity stage and the actual speed of corresponding stepping motor are as shown in table 3.Stepping motor quickens and slows down to use same speed governing algorithm.
Location algorithm: owing to will guarantee the speed smooth change of stepping motor, each velocity stage need be rotated certain step number and be guaranteed that the moment of stepping motor can not change suddenly.Especially when slowing down, guarantee that reliable step number guarantees that motor slows down in strict accordance with the speed governing algorithm.Avoid stopping operating suddenly, the moment of inertia of motor causes the stepping motor step-out, position when rotating will stepper parameter list calculate.Idiographic flow illustrates:
If current stepping motor position is p1, the target location is p2, and rotating object maximum speed grade is 30.L is the motor rotation distance, and unit is a step number.Main control module at first calculates p2-p1=L, the traffic direction of the positive and negative sign stepping motor of L.Suppose that it was 1000 steps that stepping motor rotates step number, then according to shown in the parameter list of table 4 stepping motor, stepping motor runs to velocity stage 9 needs 6694 steps of operation.In other words, 1000 steps were not enough to allow the stepping motor turn to the maximum speed grade 30 of setting, stepping motor by static begin to quicken operation after, main control module 4 calculates remaining step number in real time, and with present speed and the comparison of corresponding step number accumulated value, when the residue step number is equal to or less than the step number accumulated value of present speed, forced deceleration is to next velocity stage, and when operation was 416, motor speed can reach 13 grades, when being rotated further to 544 steps, the stepper motor speed grade can once refer to 14 grades, and 456 steps of residue are less than the step number accumulated value of 14 step velocitys, stepping motor is decelerated to velocity stage 13, when turning to for 648 steps, residue 352 goes on foot, and equals the step number accumulated value of velocity stage 12, stepping motor is decelerated to velocity stage 12, by that analogy.Make until stopping, motor just in time moved for 1000 steps.
The foregoing description just lists expressivity principle of the present invention and effect is described, but not is used to limit the present invention.Any personnel that are familiar with this technology are under spirit of the present invention and scope, and the modification to the foregoing description carries out all falls within protection scope of the present invention.
Table 1 is a hyperfine controllor for step-by-step motor external communication protocol of the present invention
LEN: the length of this secondary data:
DATA: the velocity amplitude or the rotational angle data of the motor of giving according to CMD
Table 2 is step motor drive chip A3973 control protocols of the present invention
Table 3 is DAC parameter lists
Table 4 is parameter lists of stepping motor
Claims (9)
1. a hyperfine Stepping Motor Control device comprises external communication interface, control-signals generator, stepper motor driver, it is characterized in that:
Described control-signals generator comprises the programmable logic device chip and first power supply circuits thereof; This programmable logic device chip comprises rate control module (1), decoder module (2), clock module (3), and the main control module (4), flash control module (5) and the memory module (6) that connect successively, this programmable logic device chip also comprises the output interface that is used to receive the receiving port of external control instruction and Control Parameter is changed into control signal, described control-signals generator also has the control interface agreement that is used to receive the external control instruction, meticulous speed governing algorithm and Precision Orientation Algorithm;
Described stepper motor driver comprises receiving port and output port and is used to provide second power supply circuits of drive current, described receiving port links to each other with the output port of described control-signals generator, and described output port connects described Stepping Motor Control port and links to each other.
2. a kind of hyperfine Stepping Motor Control device according to claim 1, it is characterized in that, described decoder module (2) is used to receive the control command that peripheral control unit that the receiving port of described control-signals generator receives is sent, and decoding obtains target velocity, target direction and target step number and imports described main control module (4).
3. a kind of hyperfine Stepping Motor Control device according to claim 2, it is characterized in that, described main control module (4) is used for speed, direction, position that described target velocity, target direction and target location and stepping motor is current and compares, obtain the running state parameter of described stepping motor as calculated: comprise the speed of service, direction, and reach described target location by the running state parameter execution.
4. a kind of hyperfine Stepping Motor Control device according to claim 2 is characterized in that described rate control module (1) is used for the storage speed change curve, and the speed of service of control motor changes.
5. a kind of hyperfine Stepping Motor Control device according to claim 2 is characterized in that described clock module (3) is used to produce the fractional frequency signal of described control-signals generator needs.
6. a kind of hyperfine Stepping Motor Control device according to claim 2, it is characterized in that, described flash control module (5) is used for reading control data from described memory module (6), and to change this control data be to export to described motor drive module behind the suitable data format.
7. a kind of hyperfine Stepping Motor Control device according to claim 2 is characterized in that described memory module (6) is used to store the drive control data of stepping motor.
8. a kind of hyperfine Stepping Motor Control device according to claim 1 is characterized in that, described control-signals generator adopts the EMP570 chip.
9. a kind of hyperfine Stepping Motor Control device according to claim 1 is characterized in that, described stepper motor driver adopts integrated chip A3973.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110066238 CN102122913A (en) | 2011-03-18 | 2011-03-18 | Controller for hyperfine stepping motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110066238 CN102122913A (en) | 2011-03-18 | 2011-03-18 | Controller for hyperfine stepping motor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102122913A true CN102122913A (en) | 2011-07-13 |
Family
ID=44251391
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110066238 Pending CN102122913A (en) | 2011-03-18 | 2011-03-18 | Controller for hyperfine stepping motor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102122913A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104702183A (en) * | 2015-02-16 | 2015-06-10 | 北京航天发射技术研究所 | Multifunctional universal stepping motor driver |
| CN111817623A (en) * | 2020-06-12 | 2020-10-23 | 中国科学院长春光学精密机械与物理研究所 | Motor multistage subdivision control system and method based on FPGA and storage medium |
| CN113567768A (en) * | 2021-09-09 | 2021-10-29 | 深圳市诺科科技有限公司 | Phase-loss detection circuit and method for stepping motor |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005102377A (en) * | 2003-09-24 | 2005-04-14 | Gifu Univ | Multishaft motor control system |
| CN201113878Y (en) * | 2007-07-23 | 2008-09-10 | 何跃军 | Driver |
| CN101603246A (en) * | 2009-07-08 | 2009-12-16 | 广州市麦氏电子科技有限公司 | Control system of high-speed industrial sewing machine based on CPU and FPGA structure |
| CN201749341U (en) * | 2010-06-24 | 2011-02-16 | 深圳市雷泰控制技术有限公司 | Trajectory control card |
| CN202034935U (en) * | 2011-03-18 | 2011-11-09 | 上海理工大学 | Control device for stepping motor |
-
2011
- 2011-03-18 CN CN 201110066238 patent/CN102122913A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005102377A (en) * | 2003-09-24 | 2005-04-14 | Gifu Univ | Multishaft motor control system |
| CN201113878Y (en) * | 2007-07-23 | 2008-09-10 | 何跃军 | Driver |
| CN101603246A (en) * | 2009-07-08 | 2009-12-16 | 广州市麦氏电子科技有限公司 | Control system of high-speed industrial sewing machine based on CPU and FPGA structure |
| CN201749341U (en) * | 2010-06-24 | 2011-02-16 | 深圳市雷泰控制技术有限公司 | Trajectory control card |
| CN202034935U (en) * | 2011-03-18 | 2011-11-09 | 上海理工大学 | Control device for stepping motor |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104702183A (en) * | 2015-02-16 | 2015-06-10 | 北京航天发射技术研究所 | Multifunctional universal stepping motor driver |
| CN111817623A (en) * | 2020-06-12 | 2020-10-23 | 中国科学院长春光学精密机械与物理研究所 | Motor multistage subdivision control system and method based on FPGA and storage medium |
| CN113567768A (en) * | 2021-09-09 | 2021-10-29 | 深圳市诺科科技有限公司 | Phase-loss detection circuit and method for stepping motor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202034935U (en) | Control device for stepping motor | |
| CN106697334B (en) | A kind of satellite sun wing sail plate drive control method | |
| CN101499753B (en) | Brushless servo control system and driving apparatus based on permanent magnet brushless DC motor | |
| CN203434899U (en) | High-precision servo controller used for multiple motors | |
| CN108809171B (en) | Fixed-frequency PWM full-bridge motor micro-step subdivision drive control method and circuit | |
| CN102291075B (en) | Integrated circuit for driving and control three groups of stepper motors | |
| CN103078575A (en) | Integrated multifunctional controller for low-power direct-current servomotors | |
| CN102122913A (en) | Controller for hyperfine stepping motor | |
| CN202592957U (en) | High-speed shaftless transmission printing paper feeding control system | |
| CN201403064Y (en) | Brushless servo system and driving device based on permanent magnet brushless direct current motor | |
| CN201830194U (en) | Drive control device of stepping motor | |
| CN102674121A (en) | Control system of lift door motor and control method thereof | |
| CN101299589A (en) | Stepper motor movement controller based on DDS technique | |
| CN101183173A (en) | Control method for large caliber astronomical arcs movement | |
| CN204229676U (en) | A kind of cigarette machine teaching simulated experiment platform | |
| CN105048902A (en) | Micro-stepping low-noise stepping motor driving controller | |
| CN102097973B (en) | Ultrasonic motor driving controller based on embedded chip | |
| CN202586855U (en) | Automatically rotary dining-table actuating device based on singlechip control | |
| Bangji et al. | Velocity profile algorithm realization on FPGA for stepper motor controller | |
| CN105403190A (en) | Displacement detection system of stepping machine | |
| CN201325768Y (en) | Accurately locating device of fork lifter | |
| CN1588789A (en) | Multiple mani shaft synchronous control system for asynchronous motor | |
| CN203109342U (en) | Position control device for steel rolling finishing shear line | |
| CN201674453U (en) | Controller, control device and control system of driving motor | |
| CN106933261A (en) | Position following control system and control method based on stepper drive |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20110713 |