CN105322891B - A kind of multiaxis sinusoidal vibration controls drive signal generation method - Google Patents
A kind of multiaxis sinusoidal vibration controls drive signal generation method Download PDFInfo
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- CN105322891B CN105322891B CN201510280799.9A CN201510280799A CN105322891B CN 105322891 B CN105322891 B CN 105322891B CN 201510280799 A CN201510280799 A CN 201510280799A CN 105322891 B CN105322891 B CN 105322891B
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Abstract
The invention discloses a kind of multiaxis sinusoidal vibration to control drive signal generation method.The drive signal generation method carries out data retrieval according to calculation procedure according to the frequency of sinusoidal signal to be generated, amplitude, phase and four parameters of biasing in sinusoidal data list, and the data generated after retrieval are sent with fixed frequency by DA data collecting plate cards.The sinusoidal drive signals of drive signal generation method generation are highly stable, and signal can reach continuous, smooth, smoothly transition when frequency, amplitude or phase arbitrary parameter change.
Description
Technical field
The invention belongs to spacecraft dynamic environmental test field, and in particular to a kind of multiaxis sinusoidal vibration controls drive signal
Generation method.
Background technology
In multiaxis sinusoidal vibration frequency sweep test, control system requirement is in real time to the amplitude, frequency and phase of drive signal
Position is modified, so that response meets the requirement of reference spectrum.Therefore, continuous sinusoidal drive signals how are produced, and ensure letter
It is multiaxis sinusoidal vibration control software exploitation asking of must studying and solve number to reach smooth smoothly transition when parameter updates
One of topic.Multiaxis sinusoidal vibration control drive signal generation method proposed by the present invention based on data list retrieval type, according to
Frequency, amplitude, phase and four parameters of biasing of sinusoidal signal to be generated enter line number according to calculation procedure in sinusoidal data list
According to retrieval, the data generated after retrieval are sent into board by DA data with fixed frequency and sent.This method generation
Sinusoidal drive signals are highly stable, and signal can reach when the parameters such as frequency, amplitude or phase change it is continuous, smooth,
Smoothly transition.
The content of the invention
The technical problem to be solved in the present invention is that providing a kind of multiaxis sinusoidal vibration controls drive signal generation method, with
Make the sinusoidal drive signals of generation highly stable, and signal can reach company when the parameters such as frequency, amplitude or phase change
Continuous, smooth, smoothly transition.
In order to solve the above-mentioned technical problem, the invention provides a kind of multiaxis sinusoidal vibration control drive signal generation side
Method, comprise the following steps：
Four key elements of the generation of drive signal based on sinusoidal signal：Frequency, amplitude, phase and biasing,
If current, wherein the frequency of drive signal is f ' all the wayi, amplitude is A 'i, phase is α 'i, it is biased to ζ 'i, D/A adopts
Sample frequency is Fs, for the feedback by a closed loop, it is necessary to generate new drive signal, its parameter is as follows：Frequency fi, amplitude Ai, phase
Position is αi, bias ζi(i=1,2 ...), it is in particular：
(a) it is N first by the points of computer generation one, amplitude is 1 sinusoidal fundamental wave list complete cycle：
Wherein, N is points sine wave complete cycle, value 0x80000, pt=0,1,2......, N-1.
(b) the frequency f ' of certain current drive signal all the way is obtainedi, amplitude A 'i, phaseWith biasing ζ 'iFour basic parameters
The frequency f of value and new drive signal to be generatedi, amplitude Ai, phaseWith biasing ζiFour base values, wherein phaseWith points
To represent：
Wherein, αiFor the true phase of signal, unit is radian；
(c) buffer time of driving signal frequency, amplitude and phase takes the 1/4 of the new signal cycle to be generated, biasing
Buffer time takes a steady state value, i.e.,
(d) several frequency F are sent according to DAsDetermine signal frequency, amplitude, phase and the buffer point of biasing respectively with buffer time
Number Nf(i), NA(i),Nζ(i), its value is calculated with following equation respectively：
Nf(i)=Tf(i)·Fs, NA(i)=TA(i)·Fs…………………………(5)
(e) incremental change that drive signal parameters are buffered to signal parameter value to be generated by currency is calculated, uses symbol respectively
Δf(i), ΔA(i),Δζ(i) represent, calculation formula is as follows：
(f) each frequency f ' for waiting to send several points of a new frame data is determinedi(j), amplitude A 'i(j), phaseBias ζ 'i
(j) (j=0,1,2 ...), calculation formula is as follows：
f′i(j)=f 'i+(j+1)·Δf(i), A 'i(j)=A 'i+(j+1)·ΔA(i)……··…··…(9)
Wherein i is that the way of drive signal is numbered；J is the discrete digital signal point numbering of the i roads drive signal of generation.
(g) each index in sinusoidal fundamental wave for sending several points is calculated, formula is as follows：
(h) each actual value for waiting to send several points is finally calculated：
xi(j)=A 'i(j)Sine[Sj]+ζ′i(j)…………………………··(12)
The discrete series for the drive signal that formula (12) is calculated is converted into the digital quantity under DA reference voltages respectively, so
Cyclically sequence forfeited in successively afterwards it is several in a manner of be stored in DA cachings (FIFO), DA boards are to send several frequency FsBy each point according to
The smoothing processing of device can produce continuous sinusoidal drive signals after secondary submitting and after filtering.
Multiaxis sinusoidal vibration provided by the invention controls drive signal generation method, according to the frequency of sinusoidal signal to be generated
Rate, amplitude, phase and four parameters of biasing carry out data retrieval according to calculation procedure in sinusoidal data list, by the number after retrieval
According to being handled and sent with fixed frequency by DA data collecting plate cards.The sinusoidal drive signals of this method generation are non-
It is often stable, and signal can reach continuous, smooth, smoothly transition when the parameters such as frequency, amplitude or phase change.
Brief description of the drawings
The drive signal of the tunnel difference amplitudes of Tu1Wei tri-.
The drive signal of the tunnel outs of phase of Tu2Wei tri-.
The drive signal that the tunnel frequencies of Tu3Wei tri-, amplitude and phase change.
Embodiment
A kind of multiaxis sinusoidal vibration control drive signal generation method to the present invention is further described below.
(1) drive signal generation method
Multiaxis sinusoidal vibration control needs to generate multichannel independent drive signals.The generation of drive signal is based on sinusoidal signal
Four key elements：Frequency, amplitude, phase and biasing.
If current, wherein the frequency of drive signal is f ' all the wayi, amplitude is A 'i, phase is α 'i, it is biased to ζ 'i, D/A adopts
Sample frequency is Fs, for the feedback by a closed loop, it is necessary to generate new drive signal, its parameter is as follows：Frequency fi, amplitude Ai, phase
Position is αi, bias ζi(i=1,2 ...).It is transformed into new drive signal by current drive signal, there is one section of smooth transition centre
Journey.Wait after smooth transition process terminates, DA (digital-to-analogue conversion) ends are just with new drive signal parameters stably output signal.Its is detailed
Thin formation mechanism is as follows：
(a) it is N first by the points of computer generation one, amplitude is 1 sinusoidal fundamental wave list complete cycle：
Wherein N is points sine wave complete cycle, value 0x80000, pt=0,1,2......, N-1.
(b) the frequency f ' of certain current drive signal all the way is obtainedi, amplitude A 'i, phaseWith biasing ζ 'iFour basic parameters
The frequency f of value and two-way drive signal to be generatedi, amplitude Ai, phaseWith biasing ζiFour base values, wherein phaseWith point
Count to represent (αiFor the true phase of signal, unit is radian)：
(c) change of any driving signal frequency all the way, four amplitude, phase and biasing basic parameters is not to be mutated
Interior generation, but one section of buffering course is needed, to reach the smooth transition of parameter.This section of buffering course is with parameter buffer time
To represent.The buffer time of driving signal frequency, amplitude and phase takes the 1/4 of new signal cycle to be generated, the buffering of biasing
Time takes a steady state value.I.e.
(d) several frequency F are sent according to DAsDetermine signal frequency, amplitude, phase and the buffer point of biasing respectively with buffer time
Number Nf(i), NA(i),Nζ(i).Its value is calculated with following equation respectively：
Nf(i)=Tf(i)·Fs, NA(i)=TA(i)·Fs…………·………………(5)
(e) incremental change that drive signal parameters are buffered to signal parameter value to be generated by currency is calculated, uses symbol respectively
Δf(i), ΔA(i),Δζ(i) represent.Calculation formula is as follows：
(f) each frequency f ' for waiting to send several points of a new frame data is determinedi(j), amplitude A 'i(j), phase(j) ζ ', is biasedi
(j) (j=0,1,2 ...).Calculation formula is as follows：
f′i(j)=f 'i+(j+1)·Δf(i), A 'i(j)=A 'i+(j+1)·ΔA(i)…··……··…(9)
Wherein i is that the way of drive signal is numbered；J is the discrete digital signal point numbering of the i roads drive signal of generation.
(g) each index in sinusoidal fundamental wave for sending several points is calculated.Formula is as follows：
It can be seen from formula (7)~(11) when two parameters of frequency and phase of signal change, buffer time
Interior sampling rate is also what is changed over time.Only as each frequency f ' for waiting to send several pointsiAnd phase (j)Reach fiWithWhen, sampling rate just reaches a steady state value.Now the index value of each sample point and time are linear.
(h) each actual value for waiting to send several points is finally calculated：
xi(j)=A 'i(j)Sine[Sj]+ζ′i(j)…………………………(12)
The digital quantity discrete series of the above-mentioned drive signal calculated being converted into respectively under DA reference voltages, Ran Houyi
It is secondary cyclically sequence is forfeited in it is several in a manner of be stored in DA cachings (FIFO), DA plates are to send several frequency FsEach point is sent out successively
Afterwards and the smoothing processing of device can produce continuous sinusoidal drive signals after filtering.
(2) drive signal generation emulation
According to sinusoidal drive signals formation mechanism, drive signal generation program function module has been write, and in Matlab rings
The emulation of three road drive signals has been carried out under border.Different drivings can be generated when driving signal frequency, amplitude, phase parameter regulation
Signal, general main point of following three kinds of situations：
(a) drive signal of three tunnel difference amplitudes
The tunnel difference amplitude drive signal parameters table of table 1 three
| Frequency (Hz) | Amplitude (V) | Phase (°) | |
| Drive1 | 5.0 | 2.0 | 0 |
| Drive2 | 5.0 | 4.0 | 0 |
| Drive3 | 5.0 | 6.0 | 0 |
(b) drive signal of three tunnel outs of phase
The tunnel out of phase drive signal parameters table of table 2 three
| Frequency (Hz) | Amplitude (V) | Phase (°) | |
| Drive1 | 5.0 | 4.0 | 0 |
| Drive2 | 5.0 | 4.0 | 90 |
| Drive3 | 5.0 | 4.0 | 180 |
(c) drive signal that three tunnel frequencies, amplitude and phase change
The drive signal parameters table that the tunnel frequency of table 3 three, amplitude and phase change
| Frequency changes (Hz) | Amplitude changes (V) | Phase place change (°) | |
| Drive1 | 5.0→5.5 | 2.0→2.5 | 0→0 |
| Drive2 | 5.0→5.5 | 4.0→4.5 | 0→45 |
| Drive3 | 5.0→5.5 | 6.0→5.5 | 0→90 |
1~Fig. 3 of accompanying drawing sets forth simulation result of the sinusoidal signal under different frequency, amplitude and phase condition.From
Simulation result can be seen that generation driving curve continuous and derivable at Parameters variation, reach smooth transition.
Although giving detailed description and explanation to the embodiment of the present invention above, it should be noted that
We can carry out various equivalent changes and modification to above-mentioned embodiment according to the conception of the present invention, and its caused function is made
, all should be within protection scope of the present invention during with the spirit still covered without departing from specification and accompanying drawing.
Claims (2)
1. a kind of multiaxis sinusoidal vibration controls drive signal generation method, it is characterised in that the multiaxis sinusoidal vibration control is driven
Dynamic signal creating method includes：
Four key elements of the generation of drive signal based on sinusoidal signal：Frequency, amplitude, phase and biasing,
If current, wherein the frequency of drive signal is f ' all the wayi, amplitude is A 'i, phase is α 'i, it is biased to ζ 'i, D/A sample frequencys
For Fs, for the feedback by a closed loop, it is necessary to generate new drive signal, its parameter is as follows：Frequency fi, amplitude Ai, phase be
αi, bias ζi(i=1,2 ...), it is in particular:
(a) it is N first by the points of computer generation one, amplitude is 1 sinusoidal fundamental wave list complete cycle：
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Wherein, N is points sine wave complete cycle, value 0x80000, pt=0,1,2......, N-1；
(b) the frequency f ' of certain current drive signal all the way is obtainedi, amplitude A 'i, phaseWith biasing ζ 'iFour basic parameter values and
The frequency f of two-way drive signal to be generatedi, amplitude Ai, phaseWith biasing ζiFour base values, wherein phaseWith points come table
Show：
Wherein, αiFor the true phase of signal, unit is radian；
(c) buffer time of driving signal frequency, amplitude and phase takes the 1/4 of the new signal cycle to be generated, the buffering of biasing
Time takes a steady state value, i.e.,
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(d) several frequency F are sent according to DAsDetermine signal frequency, amplitude, phase and the buffering of biasing points N respectively with buffer timef
(i), NA(i),Nζ(i), its value is calculated with following equation respectively：
Nf(i)=Tf(i)·Fs, NA(i)=TA(i)·Fs…………·………………(5)
(e) incremental change that drive signal parameters are buffered to signal parameter value to be generated by currency is calculated, respectively with symbol Δf
(i), ΔA(i),Δζ(i) represent, calculation formula is as follows：
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(f) each frequency f ' for waiting to send several points of a new frame data is determinedi(j), amplitude A 'i(j), phaseBias ζ 'i(j)(j
=0,1,2 ...), calculation formula is as follows：
f′i(j)=f 'i+(j+1)·Δf(i), A 'i(j)=A 'i+(j+1)·ΔA(i)…………·…(9)
ζ′i(j)=ζ 'i+(j+1)·Δζ(i)……………(10)
Wherein i is that the way of drive signal is numbered；J is the discrete digital signal point numbering of the i roads drive signal of generation；
(g) each index in sinusoidal fundamental wave for sending several points is calculated, formula is as follows：
(h) each actual value for waiting to send several points is finally calculated：
xi(j)=A 'i(j)Sine[Sj]+ζ′i(j)……………………………(12)
The discrete series for the drive signal that formula (12) is calculated is converted into the digital quantity under DA reference voltages, Ran Houyi respectively
It is secondary cyclically sequence is forfeited in it is several in a manner of be stored in DA cachings, DA plates are to send several frequency FsAfter each point is sent out successively and pass through
The smoothing processing of wave filter can produce continuous sinusoidal drive signals.
2. multiaxis sinusoidal vibration as claimed in claim 1 controls drive signal generation method, it is characterised in that in the frequency of signal
When two parameters of rate and phase change, sampling rate is also what is changed over time in buffer time, waits to send several points when each
Frequency f 'iAnd phase (j)Reach fiWithWhen, sampling rate just reaches a steady state value, now the index value of each sample point
It is linear with the time.
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| CN101303610A (en) * | 2008-07-04 | 2008-11-12 | 西北工业大学 | Signal discrete method for signal generating device sampling step length complicated change |
| CN101741318A (en) * | 2009-12-31 | 2010-06-16 | 中国航空工业集团公司北京长城计量测试技术研究所 | Method for controlling degree of distortion of sine vibrating table |
| CN102645585A (en) * | 2012-05-14 | 2012-08-22 | 中国航空工业集团公司北京长城计量测试技术研究所 | Synchronous rapid measuring method and device for ultralow frequency sinusoidal signal phase difference |
| CN105092197A (en) * | 2015-06-19 | 2015-11-25 | 北京航天斯达科技有限公司 | Multi-degree-of-freedom sine vibration control method and controller |
| CN106130324A (en) * | 2016-06-29 | 2016-11-16 | 韩伟 | A kind of SPWM waveform controlling method based on FPGA |
| CN106502308A (en) * | 2016-09-20 | 2017-03-15 | 江苏大学 | A kind of wave generator system of ultrasonic pulse pumping signal and production method |
-
2015
- 2015-05-28 CN CN201510280799.9A patent/CN105322891B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101303610A (en) * | 2008-07-04 | 2008-11-12 | 西北工业大学 | Signal discrete method for signal generating device sampling step length complicated change |
| CN101741318A (en) * | 2009-12-31 | 2010-06-16 | 中国航空工业集团公司北京长城计量测试技术研究所 | Method for controlling degree of distortion of sine vibrating table |
| CN102645585A (en) * | 2012-05-14 | 2012-08-22 | 中国航空工业集团公司北京长城计量测试技术研究所 | Synchronous rapid measuring method and device for ultralow frequency sinusoidal signal phase difference |
| CN105092197A (en) * | 2015-06-19 | 2015-11-25 | 北京航天斯达科技有限公司 | Multi-degree-of-freedom sine vibration control method and controller |
| CN106130324A (en) * | 2016-06-29 | 2016-11-16 | 韩伟 | A kind of SPWM waveform controlling method based on FPGA |
| CN106502308A (en) * | 2016-09-20 | 2017-03-15 | 江苏大学 | A kind of wave generator system of ultrasonic pulse pumping signal and production method |
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