CN103746616A - Mobile CT synchronous scanning control system and method - Google Patents

Abstract

The invention relates to a mobile CT synchronous scanning control system, wherein a master controller is used for sending run command information to a synchronous control module; the synchronous control module is used for converting the command information to controlled quantity of each driver and respectively sending the controlled quantity to a driver of a rotating frame rotary motor control module and a driver of a rotating frame horizontal motor control module; the drivers of the rotating frame rotary motor control module and the rotating frame horizontal motor control module are used for respectively driving respective motors according to the controlled quantity; encoders of the rotating frame rotary motor control module and the rotating frame horizontal motor control module are used for feeding back actual locations and speed information to the synchronous control module; and the synchronous control module is also used for calculating synchronized error and compensation of the above dual motors according to the actual locations and speed information of the motors. The invention also relates to a mobile CT synchronous scanning control method.

Description

Mobile CT synchronous scanning control system and method

[technical field]

The present invention relates to a kind of mobile CT synchronous scanning control system and method.

[background technology]

In current CT helical scanning synchronous control system, the mechanical drive train modes that adopt more, the increase of the quantity of inner part like this, not only increased cost pressure, and run counter to the original intention of mobile CT portable design, the intrinsic step problem of losing of stepping motor that mobile CT moves horizontally employing has simultaneously reduced again the synchronous precision of spiral.

Mobile CT scanner has multiple imaging pattern, and wherein a kind of is helical scanning.Under this pattern, the rotary frame that carries the image chain critical pieces such as X ray bulb, detector, data acquisition system drives by direct driving motor, carries out continuous rotation, and rotary frame moves horizontally simultaneously.These two kinds of motions have certain position corresponding relation, to reach uniform data for projection collection.In fact, no matter be above-mentioned direct driving motor or alternating current machine, in motion process, be all difficult to guarantee absolute uniform motion, speed exists fluctuation to be difficult to avoid.Therefore, in implementation process, need to adopt a kind of synchronous control technique, to realize the object of uniform sampling.Application number is that 201110273871.7 patent application has proposed the scheme that master-slave synchronisation control strategy is realized bi-motor Synchronization Control, but the intrinsic defect of master-slave synchronisation control mode is while affecting when being interfered from motor, main motor can not perception and is followed the variation from motor, synchronization accuracy is poor, has certain limitation.

Current large-scale fixation of C T scanner is in mechanical structure, rotary frame and horizontal moving bed be two separately parts independently, rotary frame and scanning bed load are differed greatly, the master-slave synchronisation control method that this structure adopts, once be disturbed from motor, main motor can not be followed the tracks of the variation from motor in time, and synchronization accuracy is poor, and limitation is very large.

[summary of the invention]

In view of this, the invention provides a kind of mobile CT synchronous scanning control system, comprise main controller, rotary frame electric rotating machine control module, the horizontal motor control module of rotary frame and synchronization control module, wherein, described rotary frame electric rotating machine control module and the horizontal motor control module of described rotary frame include driver, motor and encoder separately.Described main controller is for sending action command information to synchronization control module; The action command information that described synchronization control module sends for receiving main controller, this command information is converted to the controlled quentity controlled variable of each driver current time in rotary frame electric rotating machine control module, the horizontal motor control module of rotary frame, and this controlled quentity controlled variable is sent to respectively to rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame driver separately; The driver of described rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame is for driving motor separately according to described controlled quentity controlled variable respectively; The encoder of described rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame is used for collecting respectively position, the velocity information of above-mentioned each motor reality, and the position of described reality, velocity information are fed back to synchronization control module; Described synchronization control module is also for counting according to the position of above-mentioned each motor reality, velocity information and synchronous error transferometer the synchronous error of stating bi-motor in, then according to described synchronous error, calculate compensation rate, real-Time Compensation is to rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame, to realize the precise synchronization of bi-motor.

Described controlled quentity controlled variable comprises: position, the velocity information of horizontal each motor of motor control module of rotary frame electric rotating machine control module and rotary frame.

Described synchronous error transfer function is defined as:

${\mathrm{\ϵ}}_c=\frac{1}{1+\frac{\mathrm{\β}}{\mathrm{\α}}}{\mathrm{\ϵ}}_0=\frac{1}{1+G{C}_c}{\mathrm{\ϵ}}_0=G_c{\mathrm{\ϵ}}_0$

Wherein, Gc is synchronous error transfer function:

α＝(1+G _pyG _y)(1+G _pxG _x)

$\mathrm{\β}=C_c{G}_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+C_c{G}_x{C}_x^2(1+G_{\mathrm{py}}{G}_y)$

$G=G_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+G_x{G}_x^2(1+G_{\mathrm{py}}{G}_y).$

Described synchronization control module comprises ARM Synchronization Control plate.

Described ARM Synchronization Control plate comprises MCU unit, rotary frame electric rotating machine driver interface, the horizontal motor driver interface of rotary frame, D/A conversion unit, serial interface, jtag interface and CAN interface.

Described CAN interface is for realizing the communication between ARM Synchronization Control plate and main controller.

Described D/A conversion unit is for converting described command information to analog signal.

In view of this, a kind of method that the present invention also provides mobile CT synchronous scanning to control, comprising: synchronization control module receives the action command information that main controller sends; Synchronization control module converts the described action command information of receiving to the controlled quentity controlled variable of each driver current time in rotary frame electric rotating machine control module, the horizontal motor control module of rotary frame, and this controlled quentity controlled variable is sent to respectively to rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame driver separately; The driver of described rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame drives motor separately according to described controlled quentity controlled variable respectively; The encoder of described rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame is collected respectively position, the velocity information of above-mentioned each motor reality, and the position of described reality, velocity information are fed back to synchronization control module; Described synchronization control module counts according to the position of above-mentioned each motor reality, velocity information and synchronous error transferometer the synchronous error of stating bi-motor in, then according to described synchronous error, calculate compensation rate, real-Time Compensation is to rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame, to realize the precise synchronization of bi-motor.

Described controlled quentity controlled variable comprises: position, the velocity information of horizontal each motor of motor control module of rotary frame electric rotating machine control module and rotary frame.

Described synchronous error transfer function is defined as:

${\mathrm{\ϵ}}_c=\frac{1}{1+\frac{\mathrm{\β}}{\mathrm{\α}}}{\mathrm{\ϵ}}_0=\frac{1}{1+G{C}_c}{\mathrm{\ϵ}}_0=G_c{\mathrm{\ϵ}}_0$

Wherein, Gc is synchronous error transfer function:

α＝(1+G _pyG _y)(1+G _pxG _x)

$\mathrm{\β}=C_c{G}_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+C_c{G}_x{C}_x^2(1+G_{\mathrm{py}}{G}_y)$

$G=G_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+G_x{G}_x^2(1+G_{\mathrm{py}}{G}_y).$

Described synchronization control module comprises ARM Synchronization Control plate.

The present invention moves CT synchronous scanning control system and method, can realize the precise synchronization of bi-motor under mobile CT spiral synchronous scanning mode, improves image quality under CT helical scan mode.

[accompanying drawing explanation]

Fig. 1 is that rotary frame electric rotating machine (motor 1), the horizontal motor of rotary frame (motor 2) are at the track while scan schematic diagram in space.

Fig. 2 is the outline of straight line schematic diagram after motor 1 and motor 2 couplings.

Fig. 3 is the non-cross-coupling control system architecture diagram of Dual-motor synchronous control system.

Fig. 4 is Dual-motor synchronous control system cross-coupling control system architecture diagram.

Fig. 5 is mobile CT spiral synchronous scanning control system hardware structure figure.

Fig. 6 is ARM Synchronization Control plate hardware circuit schematic diagram.

Fig. 7 is the operation process chart that the present invention moves CT synchronous scanning control system and method.

[embodiment]

Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.

For explaining better the present invention, first synchronous error and cross-couplings synchronous error transfer function are defined.

Synchronous error:

In mobile CT bi-motor spiral motion synchronous control system, rotary frame electric rotating machine (motor 1) is continuously and smoothly along vertical plane and is rotatablely moved, the horizontal motor of rotary frame (motor 2) is at horizontal plane synchronous uniform velocity rectilinear motion, and the track while scan of such two motors in space advances in the shape of a spiral.As shown in Figure 1.Two motors are done continuously and smoothly's motion in plane separately, and the synchronized relation of the two can be used following equation expression:

$L_{r1}\left(t\right)=\frac{2\mathrm{\πr}}{\mathrm{\τ}}{L}_{r2}\left(t\right)---\left(1\right)$

In formula:

L _r1(t)-rotatablely move in the rotation arc length of circumferential surface;

L _r2(t)-rectilinear motion is at the forward travel distance of horizontal plane;

The radius of turn of r-helix;

The pitch of τ-helix.

By synchronized relation formula (1), known, in bi-motor spiral motion Synchronization Control, the essence that spiral trajectory forms can be regarded rotatablely moving and straight line that the rectilinear motion of motor 2 is coupled in XY plane motor 1 as.By this coupled relation, define synchronous error, the outline of straight line after motor 1 and motor 2 couplings as shown in Figure 2.

P in Fig. 2 ^*desired locations for any reference input, the physical location of etching system operation when P is this, θ is the angle of reference point place straight line and horizontal left side axle, Ey is the at the uniform velocity tracking error of continuous rotation motion of vertical plane, Ex is the tracking error of horizontal plane synchronous linear motion, ε is system profile errors, it is defined as the beeline of desired locations and physical location, the advantage of this definition is: cross-couplings Synchronization Control and the target of compensation be make desired locations and physical location consistent, the synchronous error model building is thus a real-time error model, has practical significance.According to the geometrical relationship of each variable shown in Fig. 3, synchronous error can be expressed as:

$\left\{\begin{array}{c}\mathrm{\θ}=\mathrm{arctag}\frac{2\mathrm{\πr}}{\mathrm{\τ}}\\ \mathrm{\ϵ}=-E_X\sin \mathrm{\θ}+E_y\cos \mathrm{\θ}\end{array}\right.---\left(2\right)$

Cross-couplings synchronous error transfer function:

Cross-couplings synchronous error transfer function is used for describing the dynamic relationship of synchronous error between non-cross-coupling control system and cross-coupling control system.Feedback control problem can be simply regarded in design by this function cross coupling compensation device as.

The non-cross-coupling control system architecture diagram of Dual-motor synchronous control system as shown in Figure 3, defines ε ₀synchronous scanning synchronous error during for non-cross-coupling control.Dual-motor synchronous control system cross-coupling control system architecture diagram as shown in Figure 4, defines ε _csynchronous scanning synchronous error during for cross-coupling control.

For simplifying the analysis, make speed ring and integration ring difference equivalent G y and Gx, the ε of motor 1 and motor 2 ₀, ε _cbe respectively:

ε ₀＝-E _xC _x+E _yC _y

$=\frac{1}{(1+G_{\mathrm{py}}{G}_y)(1+G_{\mathrm{px}}{G}_x)}\·[C_y(1+G_{\mathrm{px}}{G}_x)-G_x(1+G_{\mathrm{py}}{G}_y)]\left[\begin{array}{c}{P}_{\mathrm{dy}}\\ P_{\mathrm{dx}}\end{array}\right]---\left(3\right)$

ε _c=-E _xC _x+E _yC _y

$=\frac{1}{[(1+G_{\mathrm{py}}{G}_y)(1+G_{\mathrm{px}}{G}_x)+C_c{G}_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+C_c{G}_x{C}_x^2(1+G_{\mathrm{py}}{G}_y)]}\·[C_y(1+G_{\mathrm{px}}{G}_x)-C_x(1+G_{\mathrm{py}}{G}_y)]\left[\begin{array}{c}{P}_{\mathrm{dy}}\\ P_{\mathrm{dx}}\end{array}\right]---\left(4\right)$

Simultaneous formula (3) and formula (4) obtain synchronous error transfer function:

${\mathrm{\ϵ}}_c=\frac{1}{1+\frac{\mathrm{\β}}{\mathrm{\α}}}{\mathrm{\ϵ}}_0=\frac{1}{1+G{C}_c}{\mathrm{\ϵ}}_0=G_c{\mathrm{\ϵ}}_0---\left(5\right)$

Wherein:

α＝(1+G _pyG _y)(1+G _pxG _x)

$\mathrm{\β}=C_c{G}_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+C_c{G}_x{C}_x^2(1+G_{\mathrm{py}}{G}_y)$

$G=G_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+G_x{G}_x^2(1+G_{\mathrm{py}}{G}_y)$

In formula: definition Gc is the synchronous error transfer function between non-cross-coupling control system and cross-coupling control system, and Gc is synchronous error compensation distribution controller.From formula (5), by designing suitable compensator Gc, by distribution appended synchronization error compensation amount, give the speed ring of control loop separately, can reach the object of motor 1 and motor 2 precise synchronizations.

Be illustrated in figure 5 mobile CT spiral synchronous scanning control system hardware structure figure.This system is mainly comprised of main controller, motor 1 control module, motor 2 control modules and synchronization control module four parts.Wherein, described motor 1 control module and described motor 2 control modules adopt identical control structure, and motor 1 control module comprises driver 1, motor 1 and encoder 1; Motor 2 control modules comprise driver 2, motor 2 and encoder 2; Described synchronization control module comprises ARM(Advanced RISC Machine, senior reduced instruction set computer machine) Synchronization Control plate.

Described main controller is for sending action command information to synchronization control module.

The action command information that described synchronization control module sends for receiving main controller, is converted to this command information the controlled quentity controlled variable of motor 1, motor 2 current times, and this controlled quentity controlled variable is sent to respectively to driver 1, driver 2.

Described driver 1, driver 2 are for driving motor 1, motor 2 according to described controlled quentity controlled variable.

Described encoder 1, encoder 2 be for collecting position, the velocity information of motor 1, motor 2 reality, and the position of described reality, velocity information are fed back to synchronization control module by driver 1, driver 2 respectively.

Described synchronization control module is used for according to the motor 1 of feedback, position, the velocity information of motor 2 reality, and the synchronous error of motor 1, motor 2 is calculated in the definition of synchronous error transfer function in real time, then described synchronous error is compensated through compensator Gc, finally calculate compensation rate, real-time compensator is to motor 1 control module and motor 2 control modules, to realize the precise synchronization of bi-motor.

Be illustrated in figure 6 ARM Synchronization Control plate hardware circuit schematic diagram, this ARM Synchronization Control plate comprises MCU unit, driver 1 interface, driver 2 interfaces, D/A conversion unit, serial interface, jtag interface and CAN interface.Wherein, driver 1 interface and driver 2 interfaces are electrically connected to MCU unit by drive circuit respectively, ARM Synchronization Control plate is communicated by letter with main controller by CAN interface, serial interface mainly realize with host computer between communicate by letter, debugging, jtag interface is mainly used to the programming of the program that realizes.

Below in conjunction with Fig. 5, the course of work of Fig. 6 ARM Synchronization Control plate is described.

Described MCU unit receives the action command information that main controller sends, and described command information is sent to D/A conversion unit.

Described D/A conversion unit converts described command information to analog signal, converts the controlled quentity controlled variable of motor 1 and motor 2 current times to, and described controlled quentity controlled variable comprises position, the velocity information of position, velocity information and the motor 2 of motor 1.

Described driver 1 interface sends to driver 1 by the described controlled quentity controlled variable by motor 1, and described driver 2 interfaces send to driver 2 by the controlled quentity controlled variable of motor 2.

Described driver 1 and described driver 2 are according to the controlled quentity controlled variable of described transmission, carry out the two closed-loop controls of position and speed ring, that is, driver 1 drive motors 1 moves according to corresponding speed and position, and driver 2 drive motors 2 move according to corresponding speed and position.Encoder 1 is collected now position, the velocity information of motor 1 reality, and the position of described motor 1 reality, velocity information are fed back to ARM Synchronization Control plate by driver 1; Encoder 2 is collected now position, the velocity information of motor 2 reality, and the position of described motor 2 reality, velocity information are fed back to ARM Synchronization Control plate by driver 2.

MCU unit is by position, the velocity information of motor 2 reality of the position of motor 1 reality of encoder 1 feedback, velocity information and encoder 2 feedbacks, do the poor tracking error that draws motor 1, motor 2 with the controlled quentity controlled variable of D/A conversion unit conversion, then by the tracking error of motor 1, motor 2, give in real time synchronous error transfer function.

Described synchronous error transfer function is according to the tracking error of motor 1, motor 2, calculate the synchronous error of motor 1, motor 2, then by described synchronous error through compensator Gc compensation, finally calculate compensation rate, as the controlled quentity controlled variable in next sampling period of motor 1 and motor 2.MCU unit is issued main controller by the controlled quentity controlled variable in described next sampling period by CAN interface.

Fig. 7 is the operation process chart that the present invention moves CT synchronous scanning control method.

This flow chart be take within a sampling period as example describes:

Step S401:ARM Synchronization Control plate receives the action command information that main controller sends.

Step S402:ARM Synchronization Control plate converts the command information of the main controller of receiving to analog signal by D/A conversion unit, convert the controlled quentity controlled variable of motor 1 and motor 2 current times to, described controlled quentity controlled variable comprises position, the velocity information of position, velocity information and the motor 2 of motor 1.Then ARM Synchronization Control plate sends to driver 1 by driver 1 interface by the described controlled quentity controlled variable by motor 1, by driver 2 interfaces, the controlled quentity controlled variable of motor 2 is sent to driver 2.

Step S403: the controlled quentity controlled variable that driver 1 and driver 2 send according to ARM Synchronization Control plate, carry out the two closed-loop controls of position and speed ring, that is, driver 1 drive motors 1 moves according to corresponding speed and position, and driver 2 drive motors 2 move according to corresponding speed and position.Meanwhile, encoder 1 is collected now position, the velocity information of motor 1 reality, and the position of described motor 1 reality, velocity information are fed back to ARM Synchronization Control plate by driver 1; Encoder 2 is collected now position, the velocity information of motor 2 reality, and the position of described motor 2 reality, velocity information are fed back to ARM Synchronization Control plate by driver 2.

Step S404:ARM Synchronization Control plate is by position, the velocity information of motor 2 reality of the position of motor 1 reality of encoder 1 feedback, velocity information and encoder 2 feedbacks, do the poor tracking error that draws motor 1, motor 2 with the controlled quentity controlled variable obtaining after step S402 conversion, then by the tracking error of motor 1, motor 2, give in real time synchronous error transfer function.

Step S405: synchronous error transfer function is according to the tracking error of motor 1, motor 2, calculate the synchronous error of motor 1, motor 2, then by described synchronous error through compensator Gc compensation, finally calculate compensation rate, as the controlled quentity controlled variable in next sampling period of motor 1 and motor 2.ARM Synchronization Control plate is issued main controller by the controlled quentity controlled variable in described next sampling period by CAN interface.

Circulation according to this, at interval of sampling time T _stimer interrupt location in ARM Synchronization Control plate carries out timer to interrupt processing, carry out step S401 to step S405, calculate in real time the synchronous error between motor 1, motor 2, then calculate the controlled quentity controlled variable of next sampling period motor 1 and motor 2, finally realize the precise synchronization of bi-motor.

The present invention be take mobile CT scanner and has been proposed a kind of cross-couplings Synchronization Control scheme based on synchronous error transfer function as controlled device, and hardware and the software systems that realize this synchronization policy have been designed, realize the precise synchronization of bi-motor under mobile CT spiral synchronous scanning mode, thereby improved image quality under CT helical scan mode.

The above the specific embodiment of the present invention, does not form limiting the scope of the present invention.Various other corresponding changes and distortion that any technical conceive according to the present invention is made, all should be included in the protection range of the claims in the present invention.

Claims (11)

1. a mobile CT synchronous scanning control system, it is characterized in that, this system comprises main controller, rotary frame electric rotating machine control module, the horizontal motor control module of rotary frame and synchronization control module, described rotary frame electric rotating machine control module and the horizontal motor control module of described rotary frame include driver, motor and encoder separately, wherein:

Described main controller is for sending action command information to synchronization control module;

The action command information that described synchronization control module sends for receiving main controller, this command information is converted to the controlled quentity controlled variable of each driver current time in rotary frame electric rotating machine control module, the horizontal motor control module of rotary frame, and this controlled quentity controlled variable is sent to respectively to rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame driver separately;

The driver of described rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame is for driving motor separately according to described controlled quentity controlled variable respectively;

The encoder of described rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame is used for collecting respectively position, the velocity information of above-mentioned each motor reality, and the position of described reality, velocity information are fed back to synchronization control module;

Described synchronization control module is also for counting according to the position of above-mentioned each motor reality, velocity information and synchronous error transferometer the synchronous error of stating bi-motor in, then according to described synchronous error, calculate compensation rate, real-Time Compensation is to rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame, to realize the precise synchronization of bi-motor.

2. system according to claim 1, wherein, described controlled quentity controlled variable comprises: position, the velocity information of horizontal each motor of motor control module of rotary frame electric rotating machine control module and rotary frame.

3. system according to claim 1, wherein, described synchronous error transfer function is defined as:

${\mathrm{\ϵ}}_c=\frac{1}{1+\frac{\mathrm{\β}}{\mathrm{\α}}}{\mathrm{\ϵ}}_0=\frac{1}{1+G{C}_c}{\mathrm{\ϵ}}_0=G_c{\mathrm{\ϵ}}_0$

Wherein, Gc is synchronous error transfer function:

α＝(1+G _pyG _y)(1+G _pxG _x)

$\mathrm{\β}=C_c{G}_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+C_c{G}_x{C}_x^2(1+G_{\mathrm{py}}{G}_y)$

$G=G_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+G_x{G}_x^2(1+G_{\mathrm{py}}{G}_y).$

4. system according to claim 1, wherein, described synchronization control module comprises ARM Synchronization Control plate.

5. system according to claim 4, wherein, described ARM Synchronization Control plate comprises MCU unit, rotary frame electric rotating machine driver interface, the horizontal motor driver interface of rotary frame, D/A conversion unit, serial interface, jtag interface and CAN interface.

6. system according to claim 5, wherein, described CAN interface is for realizing the communication between ARM Synchronization Control plate and main controller.

7. system according to claim 5, wherein, described D/A conversion unit is for converting described command information to analog signal.

8. the method that mobile CT synchronous scanning is controlled, comprising:

Synchronization control module receives the action command information that main controller sends;

Synchronization control module converts the described action command information of receiving to the controlled quentity controlled variable of each driver current time in rotary frame electric rotating machine control module, the horizontal motor control module of rotary frame, and this controlled quentity controlled variable is sent to respectively to rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame driver separately;

The driver of described rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame drives motor separately according to described controlled quentity controlled variable respectively;

The encoder of described rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame is collected respectively position, the velocity information of above-mentioned each motor reality, and the position of described reality, velocity information are fed back to synchronization control module;

Described synchronization control module counts according to the position of above-mentioned each motor reality, velocity information and synchronous error transferometer the synchronous error of stating bi-motor in, then according to described synchronous error, calculate compensation rate, real-Time Compensation is to rotary frame electric rotating machine control module and the horizontal motor control module of rotary frame, to realize the precise synchronization of bi-motor.

9. method according to claim 8, wherein, described controlled quentity controlled variable comprises: position, the velocity information of horizontal each motor of motor control module of rotary frame electric rotating machine control module and rotary frame.

10. method according to claim 8, wherein, described synchronous error transfer function is defined as:

${\mathrm{\ϵ}}_c=\frac{1}{1+\frac{\mathrm{\β}}{\mathrm{\α}}}{\mathrm{\ϵ}}_0=\frac{1}{1+G{C}_c}{\mathrm{\ϵ}}_0=G_c{\mathrm{\ϵ}}_0$

Wherein, Gc is synchronous error transfer function:

α＝(1+G _pyG _y)(1+G _pxG _x)

$\mathrm{\β}=C_c{G}_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+C_c{G}_x{C}_x^2(1+G_{\mathrm{py}}{G}_y)$

$G=G_y{C}_y^2(1+G_{\mathrm{px}}{G}_x)+G_x{G}_x^2(1+G_{\mathrm{py}}{G}_y).$

11. methods according to claim 8, wherein, described synchronization control module comprises ARM Synchronization Control plate.

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