RU2555215C1 - Compensation-type accelerometer - Google Patents

Abstract

FIELD: measurement equipment.SUBSTANCE: compensation-type accelerometer includes a sensitive element, an angle sensor, a phase detector of negative feedback and an integrating amplifier. A reference voltage generator is connected both to the input of the angle sensor and to the input of the phase detector of negative feedback. The comparator output is connected in series via information inputs to the torque sensor input through a level converter, a pair of waiting synchronous generators, a reversible binary counter, an adding binary counter, the output of which is connected to one of the inputs of the comparison circuit, a threshold element, an electronic key, a current generator connected to the input of the electronic key. An auxiliary frequency generator is connected to inputs of the comparator, the pair of waiting synchronous generators, the adding binary counter and the reversible binary counter. One of the outputs of the phase detector of negative feedback is connected to the input of the torque sensor through a filter. To the comparator input there introduced is a stabilising circuit containing two outlines, the input of which is connected to the output of the phase detector of negative feedback. The output of the reversible binary counter is a digital output of the compensation-type accelerometer.EFFECT: possible measurement of accelerations; a compensation-type accelerometer operates in an autooscillation mode, with astatism and with enlarged band-pass and considerable quick action.3 dwg

Description

The invention relates to measuring equipment and is intended for use in compensation type devices with a digital output in stabilization, navigation and guidance systems. It can find application in devices for measuring mechanical values of the compensation type.

A device for measuring accelerations is known (RF patent No. 2098833, class 6 G01P 15/13, publ. 10.12.97) containing a sensing element including two stationary electrodes and a movable plate, three amplifiers, two resistors, with the output of the first the amplifier is connected to the first resistor, and the input of the second amplifier is connected to the second resistor and is the output of the device. To increase the noise immunity when exposed to electrical noise, a reference voltage source, an electric signal generator, two transistor pairs, three resistors, two capacitors are introduced into it, which allow compensation of electrical noise due to the coverage of the amplifier with negative feedback.

The disadvantage of this device is the low accuracy of the measurement, since the choice of gain with hard negative feedback is limited by the condition of stability of the system.

The closest in technical solution is a compensation accelerometer (described in US Pat. RF. Compensation accelerometer, RU 2397498 C1, publ. In the invention bulletin 20.08.2010, No. 23), containing a sensitive element, the angular position of which is fixed by an angle sensor, integrating amplifier, torque sensor, electronic key, threshold element, additional integrating amplifier included in the negative feedback, negative feedbacks are introduced, one from the output of the angle sensor to the input of the adder through sequentially connecting the integrating amplifier, phase negative feedback detector, voltage-current converter, and the other from the output of the negative feedback phase detector to the adder input through a smoothing filter sequentially connected to the information inputs, an additional integrating amplifier, comparator, level converter, a couple of synchronous latches generators, reversible binary counter, comparison circuit, threshold element, electronic key, the input of which is connected to the output of the generator current, the second input of the comparison circuit is connected to the output of the summing binary counter, and the additional inputs of the comparator, waiting for synchronous generators, the summing binary counter, the reversing binary counter are connected to the output of the auxiliary frequency generator, the additional inputs of the angle sensor, the phase detector of negative feedback are connected to the output the reference voltage generator, and the output of the adder is connected to the input of the torque sensor, the outputs from the reversible binary counter and voltage converter current are respectively the digital and analog output of the compensation accelerometer.

The disadvantage of such a compensation accelerometer is the low accuracy of the measurement, due to the accuracy of the integrating analog amplifiers and the threshold element. In addition, the accuracy of the measurement depends on the parameters of the electronic key circuit that selects the information. The main error of the device is associated with the finiteness of the charge time of the capacitor of the integrating amplifier. This error leads to an aperture error inherent in a similar sampling and information processing scheme.

An object of the present invention is to expand the bandwidth of a compensation accelerometer and increase the measurement accuracy.

, (где Т - постоянная времени, n - параметр, связанный с запасом по фазе Δφ зависимостью

, s - оператор преобразования Лапласа), и на вход компаратора стабилизирующая цепь, содержащая два контура, с отставанием по фазе, с передаточной функцией

(где T₂>T₁, Т₁, T₂ - постоянные времени стабилизирующей цепи), и выход реверсивного двоичного счетчика является цифровым выходом компенсационного акселерометра.The problem is solved due to the fact that in the compensation accelerometer containing a sensitive element, the angular position of which is fixed by the angle sensor, a negative feedback phase detector connected to the output of the angle sensor through an integrating amplifier, a reference voltage generator, the outputs of which are connected to the inputs of the angle sensor and negative feedback phase detector, connected in series through information inputs from the output of the comparator to the input of the comparison circuit, level converter, steam waiting synchronous generators, a reversible binary counter, as well as a summing binary counter, the output of which is connected to one of the inputs of the comparison circuit, a threshold element, the output of which is connected to one of the inputs of the torque sensor via an electronic key, and the input to the output of the comparison circuit, the current generator connected to the electronic key input, an auxiliary frequency generator connected to the comparator inputs, pairs of standby synchronous generators, a summing binary counter and a reversible binary counter are input in the phase detector of negative feedback to one of the inputs of the torque sensor filter with transfer function

, (where T is the time constant, n is the parameter associated with the phase margin Δφ as

, s is the Laplace transform operator), and to the input of the comparator a stabilizing circuit containing two circuits, with a phase lag, with a transfer function

(where T ₂ > T ₁ , T ₁ , T ₂ are the time constants of the stabilizing circuit), and the output of the reversible binary counter is the digital output of the compensation accelerometer.

The introduction into the compensation accelerometer of two negative feedbacks, one of which contains a filter and the other a stabilizing circuit, with two circuits with a phase lag, allows you to create a device for measuring accelerations of increased accuracy, operating in self-oscillating mode, with astatism in deviation and speed, with expanded bandwidth and significant performance. In addition, the introduction of a stabilizing circuit into the compensation accelerometer eliminates the appearance of an aperiodic component, which ultimately affects the accuracy of the acceleration measurement.

The invention is illustrated by drawings, where Fig. 1 shows a functional diagram of a compensation accelerometer, Fig. 2 shows a simulation diagram of a compensation accelerometer, and Fig. 3 shows the simulation results of a compensation accelerometer.

(где Т - постоянная времени, n - параметр, связанный с запасом по фазе Δφ зависимостью

, s - оператор преобразования Лапласа). Другой выход ФДООС 4 соединен с входом стабилизирующей цепи 7. Стабилизирующая цепь 7 содержит два контура с отставанием по фазе с передаточной функцией

(где T₂>T₁, Т₁,Т₂ - постоянные времени стабилизирующей цепи). Выход стабилизирующей цепи 7 соединен с входом компаратора 8. Выход компаратора 8 соединен с входом преобразователя уровня 9, выходы которого соединены с входами пары ждущих синхронных генераторов (ЖСГ) 10 и 11. Выходы ЖСГ 10 и 11 соединены с входами реверсивного двоичного счетчика 12. Выход реверсивного двоичного счетчика 12 соединен с входом схемы сравнения 13. Другой вход схемы сравнения 13 соединен с выходом суммирующего двоичного счетчика 14. Выход схемы сравнения 13 соединен с входом с порогового элемента 15. Выход порогового элемента 15 соединен с входом электронного ключа 16, другой вход электронного ключа 16 соединен с выходом генератора тока 17. Выход электронного ключа 16 соединен с одним из входов датчика момента 18, другой вход которого соединен с выходом фильтра 6. Дополнительные входы компаратора 8, ЖСГ 10 и 11, реверсивного двоичного счетчика 12, суммирующего двоичного счетчика 14 соединены с выходом генератора вспомогательной частоты 19.The compensation accelerometer contains a sensing element 1, the angular deviation of which is recorded by the angle sensor 2. The output of the angle sensor 2 is connected to the input of the integrating amplifier 3. The output of the integrating amplifier 3 is connected to the input of the phase negative feedback detector 4 (FDOOS). Additional inputs of the angle sensor 2, FDOOS 4 are connected to the output of the reference voltage generator 5 (GON). One of the outputs FDOOS 4 is connected to the input of the filter 6 with the transfer function

(where T is the time constant, n is the parameter associated with the phase margin Δφ dependence

, s is the Laplace transform operator). Another output FDOOS 4 is connected to the input of the stabilizing circuit 7. The stabilizing circuit 7 contains two circuits with a phase lag with the transfer function

(where T ₂ > T ₁ , T ₁ , T ₂ are the time constants of the stabilizing chain). The output of the stabilizing circuit 7 is connected to the input of the comparator 8. The output of the comparator 8 is connected to the input of the level 9 converter, the outputs of which are connected to the inputs of a pair of waiting synchronous generators (ZhSG) 10 and 11. The outputs of the ZhSG 10 and 11 are connected to the inputs of the reversible binary counter 12. Output a reverse binary counter 12 is connected to the input of the comparison circuit 13. Another input of the comparison circuit 13 is connected to the output of the summing binary counter 14. The output of the comparison circuit 13 is connected to the input from the threshold element 15. The output of the threshold element 15 is connected the input of the electronic key 16, the other input of the electronic key 16 is connected to the output of the current generator 17. The output of the electronic key 16 is connected to one of the inputs of the torque sensor 18, the other input of which is connected to the output of the filter 6. Additional inputs of the comparator 8, ZhSG 10 and 11, reverse binary counter 12, a summing binary counter 14 connected to the output of the auxiliary frequency generator 19.

The internal contents of the PDEOS, the comparator, waiting synchronous generators, a reversible binary counter, a comparison circuit, a threshold element, a summing binary counter, a level converter, an adder, an integrating amplifier, differentiating filters and an integrator are given in the book: P. Horowitz, W. Hill. The art of circuitry. M .: Mir, t1-3, 1993; N.T. Bodywork. Dynamics of automatic control systems. M .: Engineering, 1968.

, осуществляет стабилизацию параметров компенсационного акселерометра. Отрицательная обратная связь, введенная с выхода датчика угла 2 на один из входов датчика момента 18 и содержащая интегрирующий усилитель 3, ФДООС 4, стабилизирующую цепь 7, содержащую два контура, с отставанием по фазе, передаточной функцией

, компаратор 8, преобразователь уровня 9, пару ЖСГ 10 и 11, реверсивный двоичный счетчик 12, схему сравнения 13, пороговый элемент 15, электронный ключ 16, обеспечивает различное быстродействие компенсационного акселерометра при различном входном воздействии и астатизм по отклонению и по скорости.Compensation accelerometer works as follows. Under the action of the acceleration W on the sensing element 1, made in the form of a pendulum, the inertial moment equal to m · l · W (where m, l is the mass and length of the pendulum) acts. Under the influence of this moment, the sensor 1 is deflected, which is detected by the angle sensor 2, the field windings of which are connected to the output of the GON 5. The signal from the angle sensor 2, after amplification by the integrating amplifier 3, is fed to the input of FDOOS 4. Using FDOOS 4 and GON 5 the phase of deviation of the sensing element 1 is highlighted, and at the output of FDOOS 4 the signal will always be in antiphase of the deviation of the sensitive element 1. The signal from the output of FDOOS 4 in the form of voltage is fed to the input of the filter 6, and then to one of the inputs of the torque sensor 1 8. One of the outputs FDOOS 4 is connected to the input of the stabilizing circuit 7. The stabilizing circuit 7, containing two circuits with a phase lag, provides low speed with low input acceleration and high speed with significant acceleration (Fig.3). The output of the stabilizing circuit 7 is connected to the input of the comparator 8. In the comparator 8, the signal from the output of the stabilizing circuit 7 is compared with the signal of the selected signal that is stable in frequency and amplitude from the output of the auxiliary frequency generator 19. If the signal from output 7 is more than the triangular voltage from the output of the auxiliary generator frequency 19, then at the output of comparator 8 there will be a high logic level, if less, then at the output of comparator 8 there will be a low logic level. The signal level from the output of the comparator 8 depends on the phase of the deviation of the sensitive element 1. The signal from the output of the comparator 8 in the form of a level is fed to the input of the level 9 converter, and then to the inputs of the waiting synchronous generators 10 and 11, which with the help of the auxiliary frequency generator 19 provide signals to the form of a pulse for each impact of the input signal (from the output of the level 9 converter) equal to "1". The reversible binary counter 12, by a signal from the auxiliary frequency generator 19, counts the single pulses coming from the output of the waiting synchronous generator 10, and subtracts the pulses coming from the output of the waiting synchronous generator 11. The reverse binary counter 12 represents the positive information in the direct code, and the negative information in additional code, and the conversion of the additional code is carried out by the comparison circuit 13 and the summing binary counter 14. After a logical comparison of the signals in the circuit compared 13, the signal from output 13 is fed to the input of the threshold element 15, and then in the form of a level to the input of the electronic key 16. The parameters of the electronic key 16 are stabilized by the current generator 17. At the output of the electronic key 16 there will be pulses, the number of which is proportional to the binary code supplied to the input of the comparison circuit 13. The input of the torque sensor 18 receives signals from the output of the filter 6 and from the output of the electronic key 16. The signal fed to the current winding of the torque sensor 18 will be with a sign of the sign of the reversible binary s etchika 12. Yield reversible binary counter 12 is the output of the digital code compensating accelerometer. Negative feedback implemented from the output of the angle sensor 2 to the input of the torque sensor 18 and containing an integrating amplifier 3, FDOOS 4 and filter 6, with a transfer function

, stabilizes the parameters of the compensation accelerometer. Negative feedback introduced from the output of the angle sensor 2 to one of the inputs of the torque sensor 18 and containing an integrating amplifier 3, FDOOS 4, a stabilizing circuit 7 containing two circuits, with a phase lag, the transfer function

, a comparator 8, a level 9 converter, a couple of ZhSGs 10 and 11, a reversible binary counter 12, a comparison circuit 13, a threshold element 15, an electronic key 16, provides different speed of the compensation accelerometer for various input effects and astatism in deviation and speed.

Modeling an analog model of a compensation accelerometer (Fig. 2) with parameters: T = 0.2 s, with the width of the ambiguity zone of the threshold element equal to ± 0.01, and the simulation results are presented in Fig. 3. From the analysis of transients it follows that the device is stable (filter 6 provides stability) and at the model output we have discrete signals whose frequency depends on the device parameters.

The introduction of two negative feedbacks into the compensation accelerometer allows you to create a device for measuring accelerations with astatism, operating in a self-oscillating mode, with an expanded bandwidth and significant speed.

Claims (1)

A compensation accelerometer containing a sensor whose angular position is fixed by an angle sensor, a negative feedback phase detector connected to the output of the angle sensor through an integrating amplifier, a reference voltage generator, the outputs of which are connected to the inputs of the angle sensor and the negative feedback phase detector, connected in series information inputs from the output of the comparator to the input of the comparison circuit - level converter, a couple of waiting synchronous generators, reversible a binary counter, as well as a summing binary counter, the output of which is connected to one of the inputs of the comparison circuit, a threshold element, the output of which is connected to one of the inputs of the torque sensor via an electronic key, and the input to the output of the comparison circuit, a current generator connected to the input of the electronic key Auxiliary frequency generator connected to the comparator inputs, pairs of waiting synchronous generators, a summing binary counter and a reversible binary counter, characterized in that phase detectors are introduced into it ora negative feedback to one of the torque sensor input filter with a transfer function $$W\left(s\right)=\frac{T\cdot s+\mathrm{one}}{\frac{T}{n}\cdot s+\mathrm{one}}$$

(where T is the time constant, n is the parameter associated with the phase margin $$\Delta \varphi$$

addiction $$\Delta \varphi =\arcsin \frac{n-\mathrm{one}}{n+\mathrm{one}}$$

, s is the Laplace transform operator), and to the input of the comparator a stabilizing circuit containing two circuits, with a phase lag, with a transfer function $$W\left(s\right)=\frac{{\left(T_2\cdot s+\mathrm{one}\right)}^2}{{\left(T_{\mathrm{one}}\cdot s+\mathrm{one}\right)}^2}$$

(where T ₂ > T ₁ , T ₁ , T ₂ are the time constants of the stabilizing circuit), and the output of the reversible binary counter is the digital output of the compensation accelerometer.

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