CN101900554B - Method for digitally driving and detecting multi-gauge head gyroscope - Google Patents

Abstract

The invention discloses a method for digitally driving and detecting a multi-gauge head gyroscope, and belongs to the field of micro-mechanical gyroscope signal processing. The method comprises the following steps of: generating a carrier wave Vi by a digital method, simultaneously generating drive signals Vd1, Vd2,..., and VdN by a drive circuit, and loading the carrier wave Vi and the drive signals Vd1, Vd2,..., and VdN on the gauge head 1, the gauge head 2,..., and the gauge head N of the gyroscope in sequence, wherein N is more than or equal to 2; detecting drive mode capacitors C1, C2,..., and CN, adjusting the drive signals Vd1, Vd2,..., and VdN according to the detected signals so as to make the N gauge heads of the gyroscope work at resonance points; and based on the driving of the gyroscope, detecting sensitive mode capacitors C'1, C'2,..., and C'N, obtaining N angular velocity signals of the gyroscope, and according to N frequency sweeping states S1, S2,..., and SN of the gyroscope, processing the detected angular velocity signals and outputting the final angular velocity by a controller. The method is mainly characterized by locking the resonance frequency by a method of detecting the amplitude of the drive output signal by sweep frequency and has the advantages of the realization of self correction, high frequency stability and high anti-interference ability.

Description

A kind of more top header digitizing driving and detection method

One, technical field

The present invention relates to a kind of more top header digitizing driving and detection method, belong to micromechanical gyro signal process field.

Two, background technology

Micromechanical gyro is typical inertia device.It is for traditional mechanical gyro, optical fibre gyro and laser gyro, have physical dimension little, in light weight, low in energy consumption, start fast, cost is low, reliability is high and be easy to advantage such as digitizing, therefore range of application enlarges rapidly, can be used for car for guarding against side turned over, flight attitude control, attitude of satellite control, camera is anti-shake, auto-navigation system, various aspects such as Micro Aerial Vehicle.The gyro circuit is the important component part of micromechanical gyro.Traditional mimic channel because the characteristic of analog device itself is inevitably introduced temperature and floated, be difficult to accurately realize from demarcation and self calibration, and digital circuit can not exist temperature to float at calculating process, realizes easily from demarcating and self calibration yet.The micromechanical gyro driving circuit divides open loop and closed loop: the open loop driving circuit all is that the signal with fixed frequency goes to drive gyro work; Closed-loop driving circuit is to use the method for self-sustained oscillation or phaselocked loop that the gyro gauge outfit is operated on the resonance frequency.For the micromechanical gyro system, after the work, total system is floated with regard to there being serious temperature for a long time, can not be used for work for a long time so open loop drives.The number of applying for a patent is 200810223041 patent, propose a kind of micromechanical gyroscope self-exciting and drive demodulating equipment, obtain the vibration displacement voltage signal that micromechanical gyro drives mass and detects mass by input signal interface circuits, singlechip chip extracts level automatic gaining controling algorithm generation gain control signal by amplitude and passes to AGC (automatic gain control) system, AGC (automatic gain control) system produces variable voltage according to the drive displacement signal that gain control signal and input signal interface circuits send, feed back to the gyro drive end and realize gyro is driven the adjustment of signal, calculate input angular velocity in the inner demodulation of single-chip microcomputer simultaneously.This invention is used single-chip microcomputer to make signal and is handled, and can reduction system temperature float, and it is integrated to be beneficial to realization.But also exist not enough: system stability was poor when gyro gauge outfit resonance frequency deviation was big.

Three, summary of the invention

In order to overcome the defective on the prior art, the present invention proposes a kind of more top header digitizing driving and detection method, utilize the locking of the method realization gyro gauge outfit resonance frequency of frequency sweep, and in time proofread and correct driving the signal amplitude size, detect angular velocity signal simultaneously.

Consult Fig. 1, this method produces carrier wave V by numerical approach _i, produced by driving circuit simultaneously and drive signal V _D1, V _D2V _DN, with carrier wave V _iWith driving signal V _D1, V _D2V _DNBe loaded into gyro gauge outfit 1 successively, gyro gauge outfit 2 ... above the gyro gauge outfit N, N 〉=2 are detected and are driven the mode capacitor C ₁, C ₂C _N, drive signal V according to detected signal adjustment _D1, V _D2V _DN, make N gyro gauge outfit be operated in tuning-points.On the basis that gyro drives, detect responsive mode capacitor C ' ₁, C ' ₂C ' _N, obtain the angular velocity signal of N gyro

By the frequency sweep state S of controller according to N gyro ₁, S ₂S _N, handle detected angular velocity signal

Export final angular velocity

For each gyro gauge outfit n, the n value is 1,2 ..., N, its back-end circuit is mainly driven by gyro and two parts of angular velocity detection constitute.This paper except output control, is called gyro n with driving and the testing circuit of gyro gauge outfit n and its postposition.

A kind of more top header digitizing driving method comprises the steps:

Step 1: load the initial signal V that drives at gyro gauge outfit n _DnWith carrier signal V _i, the mass after the signal loading in the gyro gauge outfit can vibrate, and the amplitude of vibration is reflected as capacitor C between two pole plates _n

Wherein, drive signal V _DnFrequency be ω _DnThe inner NCO of digit chip (numerically-controlled oscillator) produces the fixed frequency sine wave signal

Handle the sinusoidal signal V that obtains simulating through rearmounted then _iThe rearmounted processing comprises D/A conversion (digital signal is to analog signal conversion), low-pass filtering, amplification process successively, and this paper rearmounted processing procedure cited below is also identical.And the digital signal of the simulating signal X correspondence of mentioning herein all is expressed as

Step 2: detect gyro gauge outfit n and drive the mode capacitor C _nBy charge amplifier or trans-impedance amplifier, carry out C/V conversion (electric capacity is to the conversion of voltage signal), will drive the plates capacitance C of mode _nVariation delta C _n, be converted into voltage signal C _An

Step 3: the voltage signal V of the gyro n that previous step is obtained _An, by A/D conversion (simulating signal is to the digital signal conversion), change into digital signal

Send into digital signal processing chip.

Step 4: the digital signal that previous step is obtained

Detect through amplitude, obtain signal

Amplitude

Step 5: data storage.For gyro n, when being in the frequency sweep process, every variation frequency once, with detected signal amplitude

Store.When gyrocontrol was worked, amplitude of every detection was all incited somebody to action

Put into storer, storage detects nearest M next driving signal amplitude M 〉=2 wherein.

Step 6: when gyro starts, frequency sweep caging n resonance frequency, the frequency control word W that it is corresponding _DnInput NCO produces driving frequency.Every frequency control word that changes then produces the amplitude-frequency correction coefficient k corresponding with frequency simultaneously _N1When gyro is worked, according to the amplitude information of monitoring, export instant correction coefficient k _N2With k _N1And k _N2Addition gets the amplitude rectification coefficient k _nExport.Output frequency sweep status word S when frequency sweep _n, S wherein _nValue 0 or 1,0 represents gyro n does not have frequency sweep, and 1 represents gyro n just in frequency sweep.Simultaneously in the reading system just at the number S of frequency sweep gyro _NumK wherein _N1, k _N2And k _nBe B position scale-of-two, B 〉=4,

Set F ₀Be the amplitude of driving force, ω _dFor driving angular frequency, m _xBe the equivalent mass of driving mode,

Be the resonance angular frequency of driving mode,

For driving the damping ratio of mode, then drive the amplitude B of mode stable oscillation _xFor:

$B_x=\frac{F_0}{m_x{\mathrm{\ω}}_x^2\sqrt{{(1-\frac{{{\mathrm{\ω}}_d}^2}{{\mathrm{\ω}}_x^2})}^2+4{\mathrm{\δ}}_x^2{\left(\frac{{\mathrm{\ω}}_d}{{\mathrm{\ω}}_x}\right)}^2}}---\left(1\right)$

The phase control word bit number of setting NCO is N, and frequency control word is W, and input clock frequency is F _Clk, output signal frequency F then _OutFor:

$F_{\mathrm{out}}=\frac{W\·F_{\mathrm{clk}}}{2^N}---\left(2\right)$

This step mainly comprises four parts:

1. total system frequency sweep state control

If experiment records minimum and the maximal value of the resonance angular frequency of gyro and is followed successively by ω _Min, ω _MaxFor any gyro gauge outfit n, got by formula 1, work as ω _d=ω _x=ω _MinThe time, B _xGet maximal value, namely detected amplitude is got maximal value, is designated as

When system started, gyro n carried out the resonance frequency of frequency sweep locking gauge outfit, S at this moment arbitrarily _Num=N.

After any gyro n frequency sweep is finished, immediately with the standard amplitude

Amplitude with this detection It is poor to get

Namely Set

Be frequency sweep criterion, and

Concrete judgement control is as follows:

(1) works as S _Num〉=h, gyro n do not carry out frequency sweep, and wherein h is that maximum is allowed frequency sweep gyro number, 1≤h N-1;

(2) work as S _Num≤ h-1, and

Gyro n does not carry out frequency sweep, and has and work as The time, adjust instant amplitude correction coefficient k _N2Adjust amplitude;

(3) work as S _Num≤ h-1, and

Gyro n carries out frequency sweep.

2. the generation of frequency control word

Circuit produces the frequency control word of change in the frequency sweep process, input NCO produces corresponding signal, according to driving the mode detected amplitude, finds the frequency control word W of maximum amplitude correspondence _Dn, export.

When gyro starts, get the frequency sweep frequency control word scope W of gyro n correspondence by formula 2 _{Min_n}～W _{Max_n}, wherein

When gyro starts the back frequency sweep, W _{Min_n}=W _{X_n}-Δ W _n, W _{Max_n}=W _{X_n}+ Δ W _n, W wherein _{X_n}Be the frequency control word of the gyro resonance frequency correspondence before this frequency sweep of gyro n,

A complete J level frequency sweep locking resonance frequency workflow is as follows:

During first order frequency sweep, frequency control word is from W _{Min_n}Beginning is every the time Δ T bigger range delta W that adds up _N1, input NCO produces and drives signal input gyro gauge outfit, waits stable back to gather amplitude, sends into storer, through K _N1After inferior, then gather K _N1+ 1 drives amplitude

By controller relatively

Find out maximal value and its corresponding frequency control word W _N11≤Δ W wherein _N1≤ 0.5 (W _{Max_n}-W _{Min_n}), K _N1＞(W _{Max_n}-W _{Min_n})/Δ W _N1, Δ T＞2 π/ω _{X_min}, M=K _N1+ 1.

Carry out second level frequency sweep then, swept frequency range is from W _N1-Δ W _N1To W _N1+ Δ W _N1, every the time Δ T Δ W that adds up _N2, input NCO produces and drives signal input gyro gauge outfit, waits stable back to gather amplitude, through K _N2, inferior after, gather K _N2+ 1 drives amplitude

Find out amplitude maximal value and its corresponding frequency control word W _N21≤Δ W wherein _N2＜0.5 Δ W _N1, K _N2＞2 Δ W _N1/ Δ W _N2, M=K _N2+ 1.

Carry out third level frequency sweep by same process then, fourth stage frequency sweep ... J level frequency sweep, then the frequency control word W of detected maximum amplitude correspondence in the J level frequency sweep _NJThe frequency control word W of resonance frequency correspondence then _Dn=W _NJOutput.

3. amplitude-frequency correction coefficient k _N1Generation

k _N1Be accompanied by the variation of frequency sweep process medium frequency control word and change.

Pushed away by formula 1 and 2, when the resonance, i.e. ω _d=ω _x, detected amplitude:

${\stackrel{\·\·}{V}}_{\mathrm{mn}}=\frac{G_n}{W_{\mathrm{dn}}^2}---\left(3\right)$

Wherein, G _nBe constant, W _DnFrequency control word during for resonance.Work as ω _Dn=ω _MinThe time,

Get maximal value Be decided to be the standard amplitude, at this moment the respective frequencies control word

By formula 3 the amplitude-frequency correction coefficient of frequency control word when being W is:

$k_{n1}=2^B\·(1-\frac{W_{\min \_n}^2}{W^2})---\left(4\right)$

4. instant correction coefficient k _N2Be created in gyro frequency sweep n the time, with k _N2Zero clearing.When gyro n does not have frequency sweep, whenever detect and once drive amplitude

All with the standard amplitude

Compare: when

k _N2Basis in original value adds Δ k _n, Δ k wherein _n〉=1; When

k _N2Basis in original value subtracts Δ k _n

Step 7: the frequency control word W of the resonance frequency correspondence that step 6 is obtained _nInput NCO, control NCO produce and drive signal

Step 8: with the driving signal of step 7 generation

With the correction coefficient K that produces in the step 6 _n, send into the amplitude rectification module, the driving signal behind the output calibration

Then:

${\stackrel{\·\·}{V}}_{\mathrm{dn}}={\stackrel{\·\·}{V}}_{0\mathrm{dn}}\·(1+\frac{k_n}{2^B})---\left(5\right)$

Step 9: the rearmounted processing.Digital drive signals after previous step must be proofreaied and correct

Through D/A converter, behind low-pass filter and the amplifier, form the final signal V that drives _Dn, be added on the gyro gauge outfit n.

A kind of more top header detection method comprises the steps:

Step 1: the responsive mode capacitor C of detection gyro gauge outfit n ' _nBy charge amplifier or trans-impedance amplifier, carry out C/V conversion, with responsive mode capacitor C ' _nVariation delta C ' _n, be converted into voltage signal V _Bn

Step 2: the voltage signal V that previous step is obtained _Bn, by the A/D conversion, change into digital signal

Output.

Step 3: use carrier signal V _iThe digital signal that previous step is obtained

Carry out demodulation, get signal

Step 4: the signal that previous step is obtained Adopt the logical or low-pass filter elimination radio-frequency component of band, then obtain signal

Step 5: use the driving signal that NCO directly produces in the more top header digitizing driving method step 7

The signal that previous step is obtained

Carry out demodulation, get signal

Step 6: the signal that previous step is obtained

Adopt low-pass filtering elimination radio-frequency component, obtain angular velocity signal

Step 7: the angular velocity signal that previous step is obtained

Drive the frequency sweep status word S that step 6 obtains in the implementation method with gyro _n, carry out computing, obtain final angular velocity signal

${\stackrel{\·\·}{V}}_{\mathrm{\Ω}}=\frac{\underset{n=1}{\overset{N}{\mathrm{\Σ}}}{S}_n\·{\stackrel{\·\·}{V}}_{\mathrm{\ωn}}}{S_{\mathrm{num}}}---\left(6\right)$

Advantage of the present invention is:

1. can realize self-correcting.For with a kind of gyro, when the frequency sweep precision being made as when multistage, the locking certainly in the time of can realizing the frequency large-scope change, and do not need artificial a large amount of debugging, and allow to occur bigger mismachining tolerance, be convenient to commercial production.

2. frequency stability is good.The frequency of all signals of entire circuit all depends on crystal oscillator, and crystal oscillator has very high frequency stability.The stability of this programme itself does not rely on the phase matching degree that gyro drives, and it can realize the locking of wide range of frequencies drift, so be more suitable for working under the long-time and changeable environment.

3. good in anti-interference performance.When gyro is subjected to sudden interference, as the violent impulse of emergentness, because the driving signal of native system is produced by chip internal, the amplitude regulation and control are to gradually change, and do not carry out frequency sweep simultaneously in the work and the stable output of maintenance at any time, so be subjected to very little interference.

Four, description of drawings

Fig. 1 more top header system works block diagram

Fig. 2 gyro n fundamental diagram

Five, embodiment

It is 3, n value 1,2,3 that this example adopts the micromechanical gyro gauge outfit to count N.The resonance angular frequency scope ω of three gyro gauge outfits _XminTo ω _Xmax, ω wherein _Xmin=2 π 2990rad/s, ω _Xmax=2 π 3010rad/s.The quality factor of gyro are Q _x=1000, m _x=m _y=10 ^-6Kg, driving force F ₀=10 ^-6N, carrier frequency is 100KHz.32 of the phase control words of numeral NCO, clock frequency F _ClkBe 1MHz.Digital signal processing chip is FPGA.The sample frequency of A/D and D/A conversion is 1MHz, 16 of sampling resolutions.

Specific implementation divides gyro to drive and angular velocity detection two parts:

A kind of more top header digitizing driving method comprises the steps:

Step 1: load carrier signal V at gyro gauge outfit n _iWith driving signal V _Dn, the gyro gauge outfit can be vibrated at directions X after the signal loading, and the amplitude of vibration is reflected as two capacitor C between the pole plate _n

The driving signal V that loads when system starts _D1=V _D2=V _D3=2sin (2 π 2990t) V.

Carrier signal produces frequency 100KHz sine wave signal by the inner NCO of digit chip

Then

T=0/10 wherein ⁶, 1/10 ⁶, 2/10 ⁶, and the time t in the digital signal is identical below this example.Will

Handle the sinusoidal signal V that obtains simulating through back-end circuit _i=5sin (2 π 10 ⁵T).

Step 2: detect gyro gauge outfit n and drive the mode capacitor C _nBy charge amplifier, carry out the C/V conversion, with Δ C _n, be converted into voltage signal V _An, adopt differential mode to detect electric capacity, feedback capacity C _Fn=1pf, then output voltage is:

$V_{\mathrm{an}}=\frac{2\mathrm{\Δ}{C}_n}{C_{\mathrm{fn}}}{V}_i=\frac{2\×0.2\sin (2\mathrm{\π}\·2990t)\mathrm{pf}}{\mathrm{lpf}}\×5\sin (2\mathrm{\π}\·{10}^{5}t)V=\sin (2\mathrm{\π}\·2990t)\sin (2\mathrm{\π}\·{10}^{5}t)V---\left(1\right)$

Step 3: the voltage signal V that previous step is obtained _An, by the A/D conversion, change into digital signal If voltage+1V transforms digital signal value 2 ¹⁴, then

Amplitude 2 ¹⁴

Step 4: the digital signal that previous step is obtained Detect through amplitude, obtain signal amplitude

The current amplitude of three gyros then

Step 5: data storage.In the frequency sweep process, every variation frequency is once deposited and is once driven signal amplitude.Amplitude of every detection when steady operation is all incited somebody to action Put into storer, deposit nearest 128 and drive signal amplitude.For gyro n, the driving signal amplitude of 128 corresponding detections is followed successively by;

Step 6: when gyro starts, frequency sweep locking resonance frequency, the frequency control word W that it is corresponding _DnInput NCO produces and drives signal.Every frequency control word that changes then produces the amplitude-frequency correction coefficient k corresponding with frequency simultaneously _N1When gyro is worked, according to amplitude information, export instant correction coefficient k _N2With k _N1And k _N2Addition gets the amplitude rectification coefficient k _nExport.Output frequency sweep status word S when frequency sweep _n, simultaneously in the reading system just at the number S of frequency sweep gyro _NumK wherein _N1, k _N2And k _nAll be 16 scale-of-two, S _Num=S ₁+ S ₂+ S ₃

This step mainly comprises four parts:

1. total system frequency sweep state control

For any gyro gauge outfit n, work as ω _d=ω _x=ω _MinThe time, B _xGet maximal value, namely detected amplitude is got maximal value, is made as

When system started, 3 gyros all carried out frequency sweep locking resonance frequency, S at this moment _Num=3.

After the whole startups of 3 gyros are finished, when any gyro n is worked, instant amplitude with standard amplitude 20000 and this detection

It is poor to get

Then

Set frequency sweep criterion

To any gyro n, concrete judgement control is as follows:

(1) works as S _Num〉=2, gyro n does not carry out frequency sweep;

(2) work as S _Num≤ 1, and

Gyro n does not carry out frequency sweep, and has and work as

The time, adjust instant amplitude correction coefficient k _N2Adjust amplitude;

(3) work as S _Num≤ 1, and Gyro n carries out frequency sweep.

When gyro n carries out frequency sweep, S _n=1; Otherwise, S _n=0.

2. the generation of frequency control word

Circuit produces the frequency control word of change in the frequency sweep process, input NCO produces corresponding signal, according to driving the mode detected amplitude, finds the frequency control word W of maximum amplitude correspondence _Dn, export.

If ω _Min=2 π 2990rad/s, ω _Max=2 π 3010rad/s.When gyro starts, the frequency sweep frequency control word scope W of any gyro n correspondence _{Min_n}～W _{Max_n}, wherein

When gyro starts the back frequency sweep, W _{Min_n}=W _{X_n}-Δ W _n, W _{Max_n}=W _{X_n}+ Δ W _n, W wherein _{X_n}Be the frequency control word of the gyro resonance frequency correspondence before this frequency sweep of gyro n,

Be made as 128 in this example.Adopt the level Four frequency sweep during startup, for gyro 1, complete level Four frequency sweep locking resonance frequency workflow is as follows:

First order frequency sweep, frequency control word are from 12841952, and each interval time 1 μ s progressively increases 4096, progressively increases 21 times, up to 12927968.Each frequency variation all can be with a maximum amplitude storage, after this frequency sweep finishes, find maximal value and its corresponding frequency control word, be 12884960 (respective frequencies 3000.1353Hz) as frequency control word, determine that then second level frequency sweep frequency control word scope is 12880864 (12884960-4096)～12889056 (12884860+4096).

Second level frequency sweep, the original frequency control word is 12880864, each interval time 1 μ s frequency control word adds 256, add 32 times, find the corresponding frequency control word of maximum amplitude, as 12880370, determine third level swept frequency range 12880114 (12880370-256)～12880626 (1284370+256);

Third level frequency sweep, the original frequency control word is 12880114, each interval time 1 μ s frequency control word adds 16, add 32 times, find the corresponding frequency control word of maximum amplitude, as 12880365, true word fourth stage swept frequency range 12880349 (12880365-16)～12880381 (12880365+16);

Fourth stage frequency sweep, original frequency control word are 12880349, and each interval time 1 μ s frequency control word adds 1, adds 32 times, finds the corresponding frequency control word W of maximum amplitude ₁=12880363,12880363 input NCO are produced sine wave, the resonance frequency of gyro gauge outfit 1 is 2998.9432Hz at this moment.

Equally, the resonance frequency of caging 2,3 is 2996.6482Hz, 3001.9348Hz, respective frequencies control word W ₂=12870506 and W ₃=12893212.Then the resonance angular frequency of three gyros is ω _X1=2 π 2998.9432rad/s, ω _X2=2 π 2996.6482rad/s, ω _X3=2 π 3001.9348rad/s.

To any gyro n, after system works because of

During frequency sweep, swept frequency range is W _{Min_n}=W _{X_n}-128 to W _{Max_n}=W _{X_n}+ 128, W wherein _{X_n}Be the driving frequency control word before the frequency sweep.Then from top third level frequency sweep, carry out the secondary frequency sweep up to the locking resonance frequency.

3. amplitude-frequency correction coefficient k _N1Generation

k _N1Be accompanied by the variation of frequency sweep process medium frequency control word and change.

When resonance, i.e. ω _d=ω _x, detected amplitude:

${\stackrel{\·\·}{V}}_{\mathrm{mn}}=\frac{G_n}{W_{\mathrm{dn}}^2}---\left(2\right)$

Wherein, G _nBe constant, W _DnFrequency control word during for resonance.Work as ω _Dn=ω x _MinThe time, Get maximal value

Be decided to be the standard amplitude, be made as 20000, at this moment respective frequencies control word W _{Min_n}=12841952.

Getting frequency control word by formula 2 is W _DnThe time the amplitude-frequency correction coefficient be:

$k_{n1}=\frac{2^{16}\·{12841952}^2}{W_{\mathrm{dn}}^2}---\left(3\right)$

To gyro 1, frequency control word is 12880363 o'clock, k ₁₁=390; To gyro 2, frequency control word is 12870506 o'clock, k ₂₁=290; To gyro 3, frequency control word is 12893212 o'clock, k ₃₁=520.

4. instant correction coefficient k _N2Generation

When gyro frequency sweep n, with k _N2Zero clearing.When gyro n does not have frequency sweep, whenever detect and once drive amplitude

All with the standard amplitude

Compare: when

k _N2Basis in original value adds 1; When

k _N2Basis in original value subtracts 1.

When just frequency sweep finished, driving frequency equaled resonance frequency, then k ₁₂=k ₂₂=k ₃₂=0.So k ₁=390, k ₂=290, k ₃=520.

Step 7: the frequency control word W that previous step is obtained _D1, W _D2, W _D3Input NCO produces and drives signal

The signal amplitude of setting NCO is 20000, then has:

Step 8: with the signal of previous step generation

K with the generation of the 6th step _nSend into the amplitude rectification module successively, output signal

When just frequency sweep finished, driving frequency equaled resonance frequency, then has:

Step 9: the rearmounted processing.Will Through D/A converter, low-pass filter, amplifier are converted into simulating signal V _Dn, be added on the gauge outfit gyro n.If 2 ¹⁴Be converted into+1V voltage, then:

A kind of more top header detection method comprises the steps:

Step 1: the responsive mode capacitor C of detection gyro gauge outfit n ' _nBy charge amplifier or trans-impedance amplifier, adopt differential mode to carry out the C/V conversion, with C ' _nVariation delta C ' _n, be converted into voltage signal V _Bn, can be expressed as:

$V_{\mathrm{bn}}=-\frac{2\mathrm{\Δ}{C}_n^{\′}}{C_{\mathrm{fn}}^{\′}}{V}_i---\left(4\right)$

C ' _FnBe feedback capacity, Δ C ' _nBe capacitance change, V _iBe carrier wave.

If through the signal after amplifying be:

ω _iBe carrier frequency,

For driving signal phase, ω _DnBe driving signal frequency, V ₀Be signal amplitude, K _nBe the detection angular velocity signal of gyro n (ω), establish the motion of angle of stability speed, and K _n(ω)=0.1+ δ _n, δ _nBe stochastic error.If ω _i=2 π 10 ⁵Rad/s, V ₀=5V.

Step 2: the voltage signal V that previous step is obtained _Bn, by the A/D conversion, change into digital signal

Step 3: use carrier signal V _iThe digital signal that previous step is obtained

Carry out demodulation, namely

With

Pursue sampled point and multiply each other, get signal

Then:

For being carried in the carrier phase on the gyro n, be consistent in order to make three gyros, make carrier phase difference

Step 4: the signal that previous step is obtained

Adopt the logical or low-pass filter elimination radio-frequency component of band, then obtain signal

Wherein

Set filter gain, make G ₁(ω)=G ₂(ω)=G ₃(ω)=20000, then

Step 5: use the driving signal that NCO directly produces in the gyro driving method step 7

The signal that previous step is obtained

Carry out demodulation,

In order to guarantee three gyro output signal unanimities, make phase differential

Then have:

Step 6: the signal that previous step is obtained

Adopt low-pass filtering elimination radio-frequency component, obtain angular velocity signal

If the gain of low-pass filter is 1/20000, then:

Step 7: angular velocity control output.

${\stackrel{\·\·}{V}}_{\mathrm{\Ω}}=\frac{S_1\·{\stackrel{\·\·}{V}}_{\mathrm{\ω}1}+S_2\·{\stackrel{\·\·}{V}}_{\mathrm{\ω}2}+S_3\·{\stackrel{\·\·}{V}}_{\mathrm{\ω}3}}{S_{\mathrm{num}}}---\left(8\right)$

When not having the gyro frequency sweep, ${\stackrel{\·\·}{V}}_{\mathrm{\Ω}}=\frac{{\stackrel{\·\·}{V}}_{\mathrm{\ω}1}+{\stackrel{\·\·}{V}}_{\mathrm{\ω}2}+{\stackrel{\·\·}{V}}_{\mathrm{\ω}3}}{3}=\frac{20000(K_1\left(\mathrm{\ω}\right)+K_2\left(\mathrm{\ω}\right)+K_3\left(\mathrm{\ω}\right))}{3};$

As and when gyro 1 frequency sweep is only arranged, ${\stackrel{\·\·}{V}}_{\mathrm{\Ω}}=\frac{{\stackrel{\·\·}{V}}_{\mathrm{\ω}2}+{\stackrel{\·\·}{V}}_{\mathrm{\ω}3}}{2}=10000(K_2\left(\mathrm{\ω}\right)+K_3\left(\mathrm{\ω}\right));$

As and when only having gyro 1 not have frequency sweep, then ${\stackrel{\·\·}{V}}_{\mathrm{\Ω}}={\stackrel{\·\·}{V}}_{\mathrm{\ω}1}=20000K_1\left(\mathrm{\ω}\right).$

Claims (2)

1. a more top header digitizing driving method is characterized in that comprising the steps:

Step 1: load driver signal V on gyro gauge outfit n _DnInitial value and carrier signal V _i, the mass after the signal loading among the gyro gauge outfit n can vibrate, and the amplitude of vibration is reflected as and drives the mode capacitor C _n

Wherein, drive signal V _DnFrequency be ω _DnThe inner NCO of digital signal processing chip (numerically-controlled oscillator) produces the fixed frequency sine wave signal

Handle the sinusoidal signal V that obtains simulating through rearmounted then _iThe rearmounted processing comprises D/A conversion (digital signal is to analog signal conversion), low-pass filtering, amplification process successively, and rearmounted processing procedure cited below is also identical; And the digital signal of simulating signal X correspondence all is expressed as

Step 2: detect gyro gauge outfit n and drive the mode capacitor C _nBy charge amplifier or trans-impedance amplifier, carry out C/V conversion (electric capacity is to the conversion of voltage signal), will drive the mode capacitor C _nVariation delta C _n, be converted into voltage signal V _On

Step 3: the voltage signal V of the gyro n that previous step is obtained _On, by A/D conversion (simulating signal is to the digital signal conversion), change into digital signal

Send into digital signal processing chip;

Step 4: the digital signal that previous step is obtained

Detect through amplitude, obtain signal amplitude

Step 5: data storage; For gyro n, when being in the frequency sweep process, every variation frequency once, with detected signal amplitude

Store; When gyro n steady operation, amplitude of every detection is all incited somebody to action

Put into storer, storage detects nearest M next driving signal amplitude

M 〉=2 wherein;

Step 6: when gyro n starts, frequency sweep caging n resonance frequency, frequency control word W during with resonance _DnInput NCO produces driving frequency; Every frequency control word that changes then produces the amplitude-frequency correction coefficient k corresponding with frequency simultaneously _N1When gyro n works, according to the amplitude information of monitoring, export instant correction coefficient k _N2With k _N1And k _N2Addition gets the amplitude rectification coefficient k _nExport; Output frequency sweep status word S when frequency sweep _n, S wherein _nValue 0 or 1,0 represents gyro n does not have frequency sweep, and 1 represents gyro n just in frequency sweep; Simultaneously in the reading system just at the number S of frequency sweep gyro _NumK wherein _N1, k _N2And k _nBe B position scale-of-two, B 〉=4,

Set F ₀Be the amplitude of driving force, ω _dFor driving angular frequency, m _xBe the equivalent mass of driving mode,

Be the resonance angular frequency of driving mode,

For driving the damping ratio of mode, then drive the amplitude B of mode stable oscillation _xFor:

$B_x=\frac{F_0}{m_x{\mathrm{\ω}}_x^2\sqrt{{(1-\frac{{\mathrm{\ω}}_d^2}{{\mathrm{\ω}}_x^2})}^2+4{\mathrm{\δ}}_x^2{\left(\frac{{\mathrm{\ω}}_x}{{\mathrm{\ω}}_x}\right)}^2}}---\left(1\right)$

The frequency plot control word figure place of setting NCO is N _p, frequency control word is W, input clock frequency is F _Clk, output signal frequency F then _OutFor:

$F_{\mathrm{out}}=\frac{W\·F_{\mathrm{clk}}}{2^{N_p}}---\left(2\right)$

This step mainly comprises four parts:

First: total system frequency sweep state control

If experiment records minimum and the maximal value of the resonance angular frequency of gyro n and is followed successively by ω _Min, ω _MaxFor any gyro gauge outfit n, got by formula 1, work as ω _d=ω _x=ω _MinThe time, B _xGet maximal value, namely detected amplitude is got maximal value, is designated as

When system started, gyro n carried out the resonance frequency of frequency sweep locking gauge outfit, S at this moment arbitrarily _Num=N;

After any gyro n frequency sweep is finished, immediately with the standard amplitude

Amplitude with this detection

It is poor to get

Namely

Set

Be frequency sweep criterion, and

Concrete judgement control is as follows:

(1) works as S _Num〉=h, gyro n do not carry out frequency sweep, and wherein h is that maximum is allowed frequency sweep gyro number, 1≤h≤N-1;

(2) work as S _Num≤ h-1, and

Gyro n does not carry out frequency sweep, and has and work as

The time, adjust instant correction coefficient k _N2Adjust amplitude;

(3) work as S _Num≤ h-1, and

Gyro n carries out frequency sweep;

Second portion: the generation of frequency control word

Circuit produces the frequency control word of change in the frequency sweep process, input NCO produces corresponding signal, according to driving mode detected amplitude, frequency control word W when finding resonance _Dn, export;

When gyro starts, get the frequency sweep frequency control word scope W of gyro n correspondence by formula 2 _{Min_n}～W _{Max_n}, wherein

When gyro starts the back frequency sweep, W _{Min_n}=W _{X_n}-Δ W _n, W _{Max_n}=W _{X_n}+ Δ W _n, W wherein _{X_n}Be the frequency control word of the gyro resonance frequency correspondence before this frequency sweep of gyro n,

A complete J level frequency sweep locking resonance frequency workflow is as follows:

During first order frequency sweep, frequency control word is from W _{Min_n}Beginning is every the time Δ T bigger range delta W that adds up _N1, 1≤Δ W wherein _N1≤ 0.5 (W _{Max_n}-W _{Min_n}), input NCO produces and drives signal input gyro gauge outfit n, waits stable back to gather amplitude, sends into storer, through K _N1After inferior, then gather K _N1+ 1 drives amplitude By controller relatively

Find out maximal value and its corresponding frequency control word W _N1K wherein _N1＞(W _{Max_n}-W _{Min_n})/Δ W _N1, Δ T＞2 π/ω _{X_min}, this process M=K _N1+ 1;

Carry out second level frequency sweep then, swept frequency range is from W _N1-Δ W _N1To W _N1+ Δ W _N1, every the time Δ T Δ W that adds up _N2, 1≤Δ W wherein _N2＜0.5 Δ W _N1, input NCO produces and drives signal input gyro gauge outfit n, waits stable back to gather amplitude, through K _N2After inferior, gather K _N2+ 1 drives amplitude

Find out amplitude maximal value and its corresponding frequency control word W _N2K wherein _N2＞2 Δ W _N1/ Δ W _N2, this process M=K _N2+ 1;

Carry out third level frequency sweep by same process then, fourth stage frequency sweep ... J level frequency sweep, then the frequency control word W of detected maximum amplitude correspondence in the J level frequency sweep _NJFrequency control word W during resonance then _Dn=W _NJOutput;

Third part: amplitude-frequency correction coefficient k _N1Generation

k _N1Be accompanied by the variation of frequency sweep process medium frequency control word and change;

Pushed away by formula 1 and 2, when the resonance, i.e. ω _d=ω _x, detected amplitude:

${\stackrel{\·\·}{V}}_{\mathrm{mn}}=\frac{G_n}{W_{\mathrm{dn}}^2}---\left(3\right)$

Wherein, G _nBe constant, W _DnFrequency control word during for resonance; Work as ω _Dn=ω _MinThe time,

Get maximal value

Be decided to be the standard amplitude, at this moment the respective frequencies control word

By formula 3 the amplitude-frequency correction coefficient of frequency control word when being W is:

$k_{n1}=2^B\·(1-\frac{W_{\min \_n}^2}{W^2})---\left(4\right)$

The 4th part: instant correction coefficient k _N2Generation

When gyro n frequency sweep, with k _N2Zero clearing; When gyro n does not have frequency sweep, whenever detect and once drive amplitude All with the standard amplitude Compare: when

k _N2Basis in original value adds Δ k _n, Δ k wherein _n〉=1; When

k _N2Basis in original value subtracts Δ k _n

Step 7: frequency control word W during resonance that step 6 is obtained _DnInput NCO, control NCO produce and drive signal

Step 8: with the driving signal of step 7 generation

With the correction coefficient k that produces in the step 6 _n, send into the amplitude rectification module, the driving signal behind the output calibration

Then:

${\stackrel{\·\·}{V}}_{\mathrm{dn}}={\stackrel{\·\·}{V}}_{0\mathrm{dn}}\·(1+\frac{k_n}{2^B})---\left(5\right)$

Step 9: the rearmounted processing; Digital drive signals after previous step must be proofreaied and correct Through D/A converter, behind low-pass filter and the amplifier, form and drive signal V _DnEnd value, be added on the gyro gauge outfit n.

2. the more top header detection method based on the described more top header digitizing of claim 1 driving method comprises the steps:

Steps A: the responsive mode capacitor C of detection gyro gauge outfit n ' _nBy charge amplifier or trans-impedance amplifier, carry out C/V conversion, with responsive mode capacitor C ' _nVariation delta C ' _n, be converted into voltage signal V _Bn

Step B: the voltage signal V that steps A is obtained _Bn, by the A/D conversion, change into digital signal Output;

Step C: use carrier signal V _iThe digital signal that step B is obtained

Carry out demodulation, get signal

Step D: the signal that step C is obtained

Adopt the logical or low-pass filter elimination radio-frequency component of band, then obtain signal

Step e: use the driving signal that NCO directly produces in the described more top header digitizing driving method step 7

The signal that step D is obtained

Carry out demodulation, get signal

Step F: the signal that step e is obtained Adopt low-pass filtering elimination radio-frequency component, obtain angular velocity signal

Step G: the angular velocity signal that step F is obtained

The frequency sweep status word S that obtains with described more top header digitizing driving method step 6 _n, carry out computing, obtain final angular velocity signal

${\stackrel{\·\·}{V}}_{\mathrm{\Ω}}=\frac{\underset{n=1}{\overset{N}{\mathrm{\Σ}}}{S}_n\·{\stackrel{\·\·}{V}}_{\mathrm{\ωn}}}{S_{\mathrm{num}}}---\left(6\right).$

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