CN204374726U - A kind of digital control system based on B-spline curves high speed real-time interpolation - Google Patents

Abstract

The utility model discloses a kind of digital control system based on B-spline curves high speed real-time interpolation, comprise man-machine interaction Interface, numerical control PC CPU, numerical control motion control card, driving and actuating unit, numerically-controlled machine, pick-up unit; Described man-machine interaction Interface is made up of the touch-screen of LCD liquid crystal display, realizes the man-machine interaction dialogue of numerically-controlled machine; Described numerical control PC CPU, one end is connected with man-machine interaction Interface and realizes man-machine conversation and network communication, and the other end is connected with numerical control motion control card by PC bus, completes the B-spline curves high speed real-time interpolation motion of numerically-controlled machine.The utility model can realize high-grade, digitally controlled machine tools B-spline curves high speed real-time interpolation, improve the interpolation precision of digital control system, decrease calculated amount and the error of interpolation of B-spline curves interpolation operation, to reduce cost low, can good economic and social benefit be produced.

Description

A kind of digital control system based on B-spline curves high speed real-time interpolation

Technical field

The utility model relates to a kind of numerical control interpolation system of electromechanical integration, in particular, relates to a kind of digital control system based on B-spline curves high speed real-time interpolation.

Background technology

Along with open, Embedded numerical control device development, there is significant limitation in numerical control device in the past, be mainly manifested in system and structure:

(1) numerical control device in the past adopts traditional digital control system to be the digital control system adopting special closed system, the wherein hardware structure and software structure of digital control system, the expansion of systemic-function, repacking and maintenance are all more difficult, are generally undertaken expanding, keep in repair and debugging by production firm;

(by the restriction of motion control card and interpolation algorithm, this just makes numerical control interpolation system computation burden increase the weight of to 2 NC Interpolations in the past, and the inefficiency of numerical control interpolation system, CPU processing power will inevitably be caused limited;

(3) NC Interpolation algorithm in the past, just designs for general curve interpolating, and the validity of interpolation algorithm needs to be optimized further;

(4) numerical control interpolation system in the past, interpolation operation is complicated, the interpolation time is longer, seriously interpolation efficiency, is not the research and development of B-spline curves high-speed interpolation and design NC Interpolation disposal system specially, makes the specific aim of numerical control interpolation system and be suitable for not strong.

Summary of the invention

The utility model is limitation in order to overcome above-mentioned traditional numerical control interpolation system and deficiency, gives a kind of digital control system based on B-spline curves high speed real-time interpolation.

Technical scheme of the present invention is as follows:

Based on a digital control system for B-spline curves high speed real-time interpolation, comprise man-machine interaction Interface, numerical control PC CPU, numerical control motion control card, driving and actuating unit, numerically-controlled machine, pick-up unit; Described man-machine interaction Interface is made up of the touch-screen of LCD liquid crystal display, realizes the man-machine interaction dialogue of numerically-controlled machine; Described numerical control PC CPU, one end is connected with man-machine interaction Interface and realizes man-machine conversation and network communication, and the other end is connected with numerical control motion control card by PC bus, completes the B-spline curves high speed real-time interpolation motion of numerically-controlled machine.

Described numerical control motion control card comprises USB interface control bus, USB interface chip, RAM, B-spline curves high speed real-time interpolator, D/A conversion circuit module and difference shaping circuit module.

Particularly, described USB interface control bus adopts the pattern of serial interface bus, can ensure digital control system high speed data transfer, also can improve the real-time of digital control system transmission data simultaneously.

Described USB interface chip adopts the USB2.0CY7C68100 chip of Cypress company, realize data communication between numerical control PC CPU and DSP, described USB2.0CY7C68100 chip carries two interfaces such as command interface and fifo interface, the described command interface internal register visiting CY7C68100, the described fifo interface fifo register visiting 4 1K, easy to use, realize the high-speed transfer of data.

Described RAM is Peripheral storage module, and memory capacity is 1GB.

Described D/A conversion circuit module comprises DAC-circuit and discharge circuit, realize by the conversion of digital quantity to analog quantity, go accurately to control motor-drive circuit by analog quantity, reach numerically-controlled machine at a high speed, the requirement of high accuracy interpolation, described DAC-circuit is 16 single channels of TI company voltage that walks abreast is the imported digital to analog converter of 10V.

Described difference shaping circuit module adopts the SN75175 differential received chip of TI company, the differential signal that scrambler exports is converted to single-ended signal transmission and carries out coded treatment to the coded signal in DSP, described SN75175 differential received chip has triple gate and exports, 4 road single-ended signals are as the position feed back signal of numerical control motion control card, every road signal control A, B, C signal, realizes the position accurate feedback of numerically-controlled machine.

Described driving and actuating unit comprise driver and motor.

Particularly, described driver comprises the motor driver of x-axis, y-axis, z-axis, is made up of DRV12x motor driver, for completing x-axis, y-axis, the driving of z-axis motor.

Described motor comprises the servomotor of x-axis, y-axis, z-axis, is made up of, realizes the motion of NC Interpolation axle Sinamics V80 servo drive motor.

Described numerically-controlled machine comprises main shaft, x-axis, y-axis and z-axis, for completing high speed, the real-time interpolation of B-spline curves.

Described pick-up unit comprises photoelectric encoder and rotary transformer, for detecting the moving interpolation track of numerically-controlled machine x-axis, y-axis, z-axis.

Particularly, described numerical control PC CPU sample frequency is 300Hz.

Described B-spline curves high speed real-time interpolator comprises DSP main control module and CPLD.

Particularly, described DSP main control module adopts 32 bit DSP TMS320F2812CCS chips of TI company, have high-speed interpolation arithmetic capability and the signal handling capacity of B-spline curves, described DSP TMS320F2812CCS chip comprises the memory expansion circuit of CPU, watchdog circuit, power circuit, DSP.

Described CPLD adopts the CPLD chip MAX7000E of altera corp, by able to programme with door/or gate array and macroelement form, the feature that after having flexible in programming, system cut-off, programming information is not lost.

Further, described B-spline curves high speed real-time interpolator, for realizing the interpolation of B-spline curves, can at numerical control PC CPU enterprising line number control interpolation software and Matlab software emulation, dynamically observed precision and the error effects of interpolation curve by LCD display, do the analysis of interpolation precision and error.

The present invention compared with prior art, has the following advantages and high-lighting effect:

1) general standard interface and modular structure is adopted, comprise man-machine interaction Interface, numerical control PC CPU, numerical control motion control card, driving and actuating unit, numerically-controlled machine, pick-up unit, complete the B-spline curves high speed of numerically-controlled machine, high-precision interpolation.

2) the built-in numerical control motion control of the present invention is arranged with DSP and CPLD module, DSP has high-speed interpolation arithmetic capability and the signal handling capacity of B-spline curves, the feature that after CPLD has flexible in programming, system cut-off, programming information is not lost, by the process of DSP and CPLD module, can complete B-spline curves in real time, interpolation fast.

3) the present invention is by the planning of B-spline curves high-speed interpolation computation process, can reduce interpolation operation amount, simplify interpolation computation process, improve interpolation efficiency.

Except above these, the utility model can realize high-grade, digitally controlled machine tools B-spline curves high-speed interpolation, decreases B-spline curves error of interpolation, to reduce manufacturing cost low, can produce good economic and social benefit.

Accompanying drawing explanation

Fig. 1 is the structured flowchart of the digital control system of B-spline curves high-speed interpolation of the present invention;

Fig. 2 is the process flow diagram of B-spline curves high-speed interpolation process of the present invention;

Fig. 3 is the reference mark schematic diagram of B-spline curves high-speed interpolation of the present invention, and in figure, stain represents reference mark, and the stain in picture frame represents the reference mark selected in the preparation of reference mark scope;

Fig. 4 is the procedure chart realizing B-spline curves high-speed interpolation algorithm of the present invention;

Fig. 5 is the planning chart of B-spline curves high-speed interpolation computation process of the present invention, L in figure _i, L _i+1, L _i+3be the length of 3 adjacent planning points of interpolated point, A point is curve initial interpolated point, the node parameter u that A point is corresponding _i, B point is End of Curve interpolated point, the node parameter u that B point is corresponding _i+1, Δ u is curve interpolating increment;

Fig. 6 is the comparison diagram of B-spline curves high speed interpolation of the present invention emulation;

Fig. 7 is the process flow diagram flow chart of B-spline curves high speed interpolated data of the present invention process;

Fig. 8 is the instance graph of B-spline curves high speed real-time interpolation of the present invention;

Fig. 9 is the profile errors comparison diagram of B-spline curves high-speed interpolation of the present invention.

Embodiment

Below in conjunction with accompanying drawing, the utility model and embodiment thereof are described in further detail.

Embodiment 1:

As shown in Figure 1, a kind of digital control system based on B-spline curves high speed real-time interpolation, comprises man-machine interaction Interface, numerical control PC CPU, numerical control motion control card, driving and actuating unit, numerically-controlled machine, pick-up unit; Described man-machine interaction Interface is made up of the touch-screen of LCD liquid crystal display, realizes the man-machine interaction dialogue of numerically-controlled machine; Described numerical control PC CPU, one end is connected with man-machine interaction Interface and realizes man-machine conversation and network communication, and the other end is connected with numerical control motion control card by PC bus, completes the B-spline curves high speed real-time interpolation motion of numerically-controlled machine.

Again, the present invention adopts general standard interface and modular structure, comprise man-machine interaction Interface, numerical control PC CPU, numerical control motion control card, driving and actuating unit, numerically-controlled machine, pick-up unit, completing the B-spline curves high speed of numerically-controlled machine, high precision, high efficiency interpolation, is a distinguishing feature of the present invention.

Described numerical control motion control card comprises USB interface control bus, USB interface chip, RAM, B-spline curves high speed real-time interpolator, D/A conversion circuit module and difference shaping circuit module.

Particularly, described USB interface control bus adopts the pattern of serial interface bus, can ensure digital control system high speed data transfer, also can improve the real-time of digital control system transmission data simultaneously.

Described USB interface chip adopts the USB2.0CY7C68100 chip of Cypress company, realize data communication between numerical control PC CPU and DSP, described USB2.0CY7C68100 chip carries two interfaces such as command interface and fifo interface, the described command interface internal register visiting CY7C68100, the described fifo interface fifo register visiting 4 1K, easy to use, realize the high-speed transfer of data.

Described RAM is Peripheral storage module, and memory capacity is 1GB.

Described D/A conversion circuit module comprises DAC-circuit and discharge circuit, realize by the conversion of digital quantity to analog quantity, go accurately to control motor-drive circuit by analog quantity, reach numerically-controlled machine at a high speed, the requirement of high accuracy interpolation, described DAC-circuit is 16 single channels of TI company voltage that walks abreast is the imported digital to analog converter of 10V.

Described difference shaping circuit module adopts the SN75175 differential received chip of TI company, the differential signal that scrambler exports is converted to single-ended signal transmission and carries out coded treatment to the coded signal in DSP, described SN75175 differential received chip has triple gate and exports, 4 road single-ended signals are as the position feed back signal of numerical control motion control card, every road signal control A, B, C signal, realizes the position accurate feedback of numerically-controlled machine.

Described driving and actuating unit comprise driver and motor.

Particularly, described driver comprises the motor driver of x-axis, y-axis, z-axis, is made up of DRV12x motor driver, for completing x-axis, y-axis, the driving of z-axis motor.

Described motor comprises the servomotor of x-axis, y-axis, z-axis, is made up of, realizes the motion of NC Interpolation axle Sinamics V80 servo drive motor.

Described numerically-controlled machine comprises main shaft, x-axis, y-axis and z-axis, for completing high speed, the real-time interpolation of B-spline curves.

Described pick-up unit comprises photoelectric encoder and rotary transformer, for detecting the moving interpolation track of numerically-controlled machine x-axis, y-axis, z-axis.

Particularly, described numerical control PC CPU sample frequency is 300Hz.

Described B-spline curves high speed real-time interpolator comprises DSP main control module and CPLD.

Particularly, described DSP main control module adopts 32 bit DSP TMS320F2812CCS chips of TI company, have high-speed interpolation arithmetic capability and the signal handling capacity of B-spline curves, described DSP TMS320F2812CCS chip comprises the memory expansion circuit of CPU, watchdog circuit, power circuit, DSP.

Described CPLD adopts the CPLD chip MAX7000E of altera corp, by able to programme with door/or gate array and macroelement form, the feature that after having flexible in programming, system cut-off, programming information is not lost.

As shown in Figure 2, the step of B-spline curves high speed real-time interpolation is realized:

Step S1: start, the parameter (as reference mark, weight factor, knot vector) of input B-spline curves;

Again, the arrow value rational polynominal function of B-spline curves (nurbs curve) segmentation, its expression formula is

$p\left(u\right)=\frac{\underset{i=0}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\ω}}_i{d}_{i,k}\left(u\right)}{\underset{i=0}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\ω}}_i{N}_{i,k}\left(u\right)}=\underset{i=0}{\overset{n}{\mathrm{\Σ}}}{p}_i{N}_{i,k}\left(u\right)---\left(1\right)$

Again, in formula: d _ifor reference mark, ω _ifor weight factor.U=[u ₀, u ₁..., u _n+k+1] title U is knot vector, N _i,k ^(u)for k specification B-spline basis function (N _i,k ^(u)for k spline base function), by following formula recurrence calculation:

In formula, u _i, u _i+1, u _i+k+1all values of knot vector, constitute the knot vector of k (k+1) B-spline basis function.

Step S1-2: the reference mark determining B-spline curves high-speed interpolation;

Again, first time reads in _iindividual data point { P ₁p ₂p _i, reverse reference mark { C ₁c ₂c _i, if second time reads in i+m data point { P ₁p ₂p _i+m.

Particularly, the method at reverse reference mark is from reference mark { C ₁c ₂c _i+min, appoint and take out several somes C _i-1, C _iand C _i+m-1, C _i+m, as follows for the processing requirements at reference mark:

i-1＞i+m

(3)

i＜i+m-1

In detail, when i > 3 overlaps and data point is greater than 5, the more smooth change of curve, meets the calculating at reference mark, meets the requirement that B-spline curves determination high-speed interpolation determines reference mark.

As shown in Figure 3, for m=6, determine the reference mark of B-spline curves high-speed interpolation.

The mode at reference mark, two ends in Fig. 3 is also asymmetric, and therefore will screen the reference mark participating in controlling is C _i-1, C _iand C _i+m-1, C _i+m.

Step S1-3: the step realizing B-spline curves high-speed interpolation algorithm, as shown in Figure 4;

Step one: start to get out B-spline curves;

Step 2: B-spline curves pre-service, determines parameter increment Delta u=u _i+1-u _i;

Step 3: by u _ibe launched into t _ithe second Taylor series formula in moment;

$u_0=0,u_1=u_0+\frac{{\mathrm{\ΔL}}_0}{\sqrt{x_0^2+y_0^2+z_0^2}}---\left(4\right)$

In formula: u ₀during for i=0, the value of start node vector, u ₁for i=1 save time, the value of knot vector, x ₀, y ₀, z ₀for the initial coordinate point of curve interpolating, Δ L ₀for the arc length increment size of each interpolation cycle inner curve.

$u_{i+1}=u_i+\frac{{\mathrm{\ΔL}}_0}{\sqrt{x_i^2+y_i^2+z_i^2}}---\left(5\right)$

In formula: x _i, y _i, z _ifor knot vector u _icorresponding curve interpolating interpolation coordinate points.

ΔL ₀＝V(t)·T (6)

In formula: V (t) is the speed of feed of t B-spline curves.

Again, the computing method (p of V (t) is provided _iu () is data point corresponding in formula (1));

$V\left(t\right)=\left|\right|\frac{d{p}_i\left(u\right)}{\mathrm{dt}}\left|\right|=\left|\right|\frac{d{p}_i\left(u\right)}{\mathrm{du}}\left|\right|\frac{\mathrm{du}}{\mathrm{dt}}---\left(7\right)$

$\frac{\mathrm{du}}{\mathrm{dt}}=\frac{V\left(t\right)}{\left|\right|\frac{\mathrm{dp}\left(u\right)}{\mathrm{dt}}\left|\right|}=\frac{V\left(t\right)}{\sqrt{x_i^{\′2}+y_i^{\′2}+z_i^{\′2}}}---\left(8\right)$

Step 4: ask first order derivative;

$u_{i+1}=u_i+\frac{V\·T}{\sqrt{x_i^2+y_i^2+z_i^2}}=u_i+\frac{V\left(t\right)\·T}{\left|\frac{d{p}_i\left(u\right)}{\mathrm{dt}}\right|}---\left(9\right)$

Step 5: determine interpolation increment:

$\mathrm{\Δu}=u_{i+1}-u_i=\frac{V\left(t\right)\·T}{|\frac{{\mathrm{dp}}_i\left(u\right)}{\mathrm{dt}}{|}_{u=u_i}}>u_{\mathrm{ek}}---\left(10\right)$

In formula: u _ifor the parameter corresponding to present node position, Δ u _ifor parameter interpolation increment, u _i+1for curve interpolating is reached home the parameter corresponding to node location, u _ekfor the parameter corresponding to current interpolation plan node.

If meet above formula condition, perform step 6; Otherwise, perform from step 3;

Step 6: judged whether interpolation task, if do not complete interpolation task, then performs from step 2; If complete interpolation task, then perform step 7;

Step 7: interpolation task terminates, realizes B-spline curves high-speed interpolation.

Whether step S2: determining step S2 complete this interpolation task;

1) if do not complete this interpolation, step S1-1 is returned: determine that the step at the reference mark of B-spline curves high-speed interpolation starts interpolation and calculates;

2) if complete this interpolation, B-spline curves high-speed interpolation;

Step S3:B SPL high-speed interpolation;

As can be seen from formula (10), when other condition is certain, interpolation increment Delta u is relevant with interpolation rate V (t), can realize the Rule of judgment of B-spline curves high speed, high-precision interpolation.

Step S4:B SPL high-speed interpolation computation process is planned, as shown in Figure 5;

1) condition of B-spline curves high-speed interpolation is judged;

If formula (10) is set up, then meet the requirement of high-grade, digitally controlled machine tools high-speed interpolation.

2) treatments B SPL interpolated point

Particularly, for i interpolated point, when should meet formula (10), namely B curve interpolating reaches terminal.If there is a value u in B curve _ek, make Δ u=u _i+1-u _i> u _ek, then can differentiate that B-spline curves arrive interpolation terminal according to formula (10), B-spline curves complete interpolation.Otherwise curve exists two terminals according to speed transit case, do best optimizing process and find a best interpolated point, as last interpolated point, complete high-speed interpolation.

Again, by the planning of B-spline curves high-speed interpolation computation process, can reduce interpolation operation amount, simplify interpolation computation process, reducing the interpolation time and improve interpolation efficiency, is a distinguishing feature of the present invention.

Step S5: judge whether interpolation task all completes;

1) if do not complete whole interpolation task, the step returning step S1-3 starts interpolation and calculates;

2) if complete this interpolation, next step interpolation task is entered.

Step S6: terminate interpolation; Interpolation system completes all interpolation tasks.

Again, use the method for B-spline curves high-speed interpolations, can simplified operation, save the interpolation time.

Embodiment 2:

The experiment effect that the present invention performs, the correctness of checking B-spline curves high-speed interpolation algorithm:

Particularly, as shown in Figure 6, to curve interpolation data point x ∈ [0 2 π] random appointing, gets 60 values, calculates corresponding y value, under identical circumstances simultaneously, calculates the y value of theoretical interpolation curve and the y value of actual interpolation curve, forms former sinusoidal interpolation curve and graph of errors.

As shown in Figure 6, theoretical interpolation curve and actual interpolation curve match, and the error of theoretical interpolation curve and actual interpolation curve is less than 0.6 μm, and the algorithm demonstrating this B-spline curves high speed real-time interpolation is correct, practicable.

Embodiment 3:

Particularly, according to the B-spline curves high-speed interpolation algorithm set up, in FANUC digital control system, interpolation simulation calculation is carried out.

Again, the position vector of three-dimensional space curve is

$p(x_i,y_i,z_i)={\left\{\begin{array}{cccccccc}1& 1.5& 2.0& 4.5& 8.0& 9.0& 12.0& 14.5\\ 1& 2.0& 3.0& 3.5& 4.5& 5.0& 6.5& 7.5\\ 0.5& 1.5& 2.8& 3.2& 3.5& 4.0& 4.5& 5.8\end{array}\right\}}^{T}i=\mathrm{1,2,3},\·\·\·$

The parameter of setting B-spline curves interpolation processing, as shown in table 1.

The parameter of table 1B SPL interpolation processing

The partial data that interpolation calculates is as shown in table 2.

The data point of table 2 curve interpolating processing

Further, in FANUC digital control system, data handling procedure process flow diagram, as shown in Figure 7.

Step one: according to the requirement of B-spline curves high-speed interpolation in numerically-controlled machine, inputs a numerical control job sequence, NC program cache;

Step 2: lathe parameter (as speed of feed, interpolation cycle) is set;

Step 3: the judgement of interpolation track: if formula (10) is set up, interpolation is carried out;

Step 4: locus interpolation (carrying out interpolation by simulation parameter), error compensation (compensating by error of interpolation);

Step 5: the control interpolation data x obtaining numerically-controlled machine _i, y _i, z _i;

Step 6: control interpolation data x _i, y _i, z _isend into servo drive system, servo-drive system drives the motion of x-axis, y-axis, z-axis, completes the interpolation of B-spline curves.

Particularly, the instance graph of B-spline curves high speed real-time interpolation, as shown in Figure 8.

Further, described B-spline curves high speed real-time interpolator, for realizing the interpolation of B-spline curves, can at numerical control PC CPU enterprising line number control interpolation software and Matlab software emulation, dynamically observed precision and the error effects of interpolation curve by LCD display, do the analysis of interpolation precision and error.

Again, the present invention is by B-spline curves high speed real-time interpolator, and realizing B-spline curves high speed, high precision, high efficiency NC Interpolation, is also a distinguishing feature of the present invention.

According to the requirement that B-spline curves high speed is real-time, utilize the arbitrfary point B-spline curves interpolation parameters that NC Interpolation software and Matlab software emulation provide, make the B-spline curves profile errors figure of former B curve and this paper interpolation algorithm, as shown in Figure 9.

As can be seen from analogous diagram 9, the requirement of high-speed interpolation of the algorithm realization of B-spline curves high-speed interpolation.Although decrease profile errors from figure, the control accuracy of curve is not obvious, therefore needs error of interpolation and control accuracy, the analysis of interpolation time list, as shown in table 3.

The B-spline curves of table 3 high-speed interpolation and the analysis of virgin curve interpolation effect

Particularly, known by figure emulation 8 ~ 9 and table 3 analysis:

In the process of B-spline curves high speed real-time interpolation, interpolation precision (mm) variable quantity becomes 0.05mm from 1.0mm, the time of two kinds of curve comparison interpolations: when at number of nodes (u) be 0.1 and interpolation precision (mm) for 1.00mm time, two kinds of curve comparison interpolation times are 0.025s, when at number of nodes (u) be 0.9 and interpolation precision (mm) for 0.0315mm time, two kinds of curve comparison interpolation times are 0.0315s, there is maximal value 0.5mm and minimum value 0.002mm in the maximum error (mm) of two kinds of curve comparison interpolations, the object of interpolation is wanted in the expection so just met, namely error of interpolation is reduced, improve interpolation precision, reduce the interpolation time, meet the requirement of B-spline curves high speed real-time interpolation.

Can draw to draw a conclusion from the change of simulation curve track and the data analysis of table 3:

1), in the process of B-spline curves high-speed interpolation, error of interpolation obviously reduces, control accuracy significantly improves, and the object of interpolation is wanted in the expection so just met, and namely meets the requirement of high speed, high precision real-time interpolation.

2), in the process of B-spline curves high-speed interpolation, along with the raising of knot vector and interpolation precision, the time of B-spline curves interpolation reduces, and meets the requirement of B-spline curves high-speed interpolation.

3), simulation example shows, the realization that the simulation result of B-spline curves high-speed interpolation easily shows at the LCD of numerically-controlled machine is also dynamically observed, simulation result shows that this interpolation algorithm is better than other interpolation algorithm simultaneously, and on other numerically-controlled machine, interpolation has very strong reference.

Again, from system interpolation analogous diagram 9 and interpolation analysis of results table 3, another outstanding feature of the present invention is exactly this interpolation algorithm can realize B curve high-speed interpolation in this digital control system, meet the requirement improving interpolation precision and reduce error of interpolation simultaneously, other numerical control interpolation system has very strong reference and portability.

What finally illustrate is, above embodiment only limits in order to the technical solution of the utility model to be described, although be described the utility model by referring to preferred embodiment of the present utility model, but those of ordinary skill in the art is to be understood that, various change can be made to it in the form and details, and not depart from the spirit and scope of the present utility model that appended claims limits.

Claims (7)

1. based on a digital control system for B-spline curves high speed real-time interpolation, it is characterized in that: comprise man-machine interaction Interface, numerical control PC CPU, numerical control motion control card, driving and actuating unit, numerically-controlled machine, pick-up unit; Described man-machine interaction Interface is made up of the touch-screen of LCD liquid crystal display, realizes the man-machine interaction dialogue of numerically-controlled machine; Described numerical control PC CPU, one end is connected with man-machine interaction Interface and realizes man-machine conversation and network communication, and the other end is connected with numerical control motion control card by PC bus, completes the B-spline curves high speed real-time interpolation motion of numerically-controlled machine.

2. a kind of digital control system based on B-spline curves high speed real-time interpolation as claimed in claim 1, is characterized in that: described numerical control motion control card comprises USB interface control bus, USB interface chip, RAM, B-spline curves high speed real-time interpolator, D/A conversion circuit module and difference shaping circuit module;

1), described USB interface control bus adopts the pattern of serial interface bus, can ensure digital control system high speed data transfer, also can improve the real-time of digital control system transmission data simultaneously;

2), described USB interface chip adopts the USB2.0CY7C68100 chip of Cypress company, realize data communication between numerical control PC CPU and DSP, described USB2.0CY7C68100 chip carries two interfaces such as command interface and fifo interface, the described command interface internal register visiting CY7C68100, the described fifo interface fifo register visiting 4 1K, easy to use, realize the high-speed transfer of data;

3), described RAM is Peripheral storage module, and memory capacity is 1GB;

4), described D/A conversion circuit module comprises DAC-circuit and discharge circuit, realize by the conversion of digital quantity to analog quantity, go accurately to control motor-drive circuit by analog quantity, reach numerically-controlled machine at a high speed, the requirement of high accuracy interpolation, described DAC-circuit is 16 single channels of TI company voltage that walks abreast is the imported digital to analog converter of 10V;

5), described difference shaping circuit module adopts the SN75175 differential received chip of TI company, the differential signal that scrambler exports is converted to single-ended signal transmission and carries out coded treatment to the coded signal in DSP, described SN75175 differential received chip has triple gate and exports, 4 road single-ended signals are as the position feed back signal of numerical control motion control card, every road signal control A, B, C signal, realizes the position accurate feedback of numerically-controlled machine.

3. a kind of digital control system based on B-spline curves high speed real-time interpolation as claimed in claim 1, is characterized in that: described driving and actuating unit comprise driver and motor;

1), described driver comprises the motor driver of x-axis, y-axis, z-axis, is made up of DRV12x motor driver, and for completing x-axis, y-axis, z-axis motor drive;

2), described motor comprises the servomotor of x-axis, y-axis, z-axis, is made up of, realizes the motion of NC Interpolation axle Sinamics V80 servo drive motor.

4. a kind of digital control system based on B-spline curves high speed real-time interpolation as claimed in claim 1, is characterized in that: described numerically-controlled machine comprises main shaft, x-axis, y-axis and z-axis, for completing high speed, the real-time interpolation of B-spline curves.

5. a kind of digital control system based on B-spline curves high speed real-time interpolation as claimed in claim 1, is characterized in that: described pick-up unit comprises photoelectric encoder and rotary transformer, for detecting the moving interpolation track of numerically-controlled machine x-axis, y-axis, z-axis.

6. a kind of digital control system based on B-spline curves high speed real-time interpolation according to claim 1, is characterized in that:

Described numerical control PC CPU sample frequency is 300Hz.

7. a kind of digital control system based on B-spline curves high speed real-time interpolation according to claim 2, is characterized in that: described B-spline curves high speed real-time interpolator comprises DSP main control module and CPLD;

1), described DSP main control module adopts 32 bit DSP TMS320F2812CCS chips of TI company, have high-speed interpolation arithmetic capability and the signal handling capacity of B-spline curves, described DSP TMS320F2812CCS chip comprises the memory expansion circuit of CPU, watchdog circuit, power circuit, DSP;

2), described CPLD adopts the CPLD chip MAX7000E of altera corp, by able to programme with door/or gate array and macroelement form, the feature that after having flexible in programming, system cut-off, programming information is not lost;

3), further, described B-spline curves high speed real-time interpolator, for realizing the interpolation of B-spline curves, can at numerical control PC CPU enterprising line number control interpolation software and Matlab software emulation, dynamically observed precision and the error effects of interpolation curve by LCD display, do the analysis of interpolation precision and error.