RU2411522C1 - Compensation accelerometre - Google Patents

Abstract

FIELD: instrument making.

SUBSTANCE: accelerometre includes two local feedbacks of opposite signs. Positive feedback is formed from the amplifier output to voltage-current converter input through phase detector of positive feedback and filter of upper frequencies. Integrating negative feedback is formed on the amplifier output to input of adder subsequently via information inputs through phase detector of negative feedback, integrating amplifier, signal varying speed limit device, comparator unit, level converter, pair of triggered synchronous generators, reversible binary counter, comparison diagram, trigger, electronic switch the input of which is connected to the current generator output. Output of reversible binary counter is digital output of compensation accelerometre.

EFFECT: invention allows enlarging the pass band and improving accuracy.

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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.

Known compensation accelerometer (AS No. 742801, published in Bulletin of the Invention No. 23, 1980), comprising a sensor element, an angle sensor, an integrating feedback amplifier, a torque sensor, an additional integrating amplifier, an electronic key, a threshold element. Moreover, the first output of the angle sensor is connected through an integrating feedback amplifier to the moment sensor, and the second output of the angle sensor through a threshold element and an additional integrating amplifier is connected to the control input of the electronic key.

The disadvantage of a compensation accelerometer 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 accuracy of the compensation accelerometer depends on integrating analog amplifiers, a threshold element and an electronic key included in the feedback. The main error of the device for measuring acceleration 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.

The closest in technical solution is a device for measuring accelerations (RF patent No. 21565625 C1, G01P 15/13, published in Bulletin No. 11, 04/20/2001) containing a sensing element, an angle sensor, an amplifier and a torque sensor, local positive feedback the communication of which is introduced from the amplifier output to the input of the torque sensor through a series-connected phase detector of positive feedback and a voltage-current converter. Local negative feedback is introduced from the output of the angle sensor to the sensor input moment, through a series-connected phase detector of negative feedback, a high-pass filter and a voltage-current converter. Negative integrating feedback is introduced from the output of the phase detector of negative feedback to the input of the torque sensor and contains serially connected integrating amplifier, a comparator, waiting synchronous generators, a reversible binary counter, an additional code to direct converter, a collection circuit (OR), a binary multiplier, a smoothing filter , a sign switch and a synchronization circuit, the outputs of which are inputs for the comparator and waiting synchronous generators. The second output of the comparator is connected to the second input of the reversible binary counter via a standby synchronous generator, while the second output of the reversible binary counter is connected to the second input of the sign switch and the second input of the collection circuit, the output of which is the output of the digital code of the device. In addition, the device contains a reference voltage generator, the outputs of which are inputs for an angle sensor, a phase detector of positive and negative feedbacks.

The disadvantage of the device for measuring acceleration is the dependence of the accuracy of the measurement of acceleration on the spread of transmission coefficients in local positive and negative feedbacks.

The objective of the present invention is to expand the bandwidth of the compensation accelerometer and improve the accuracy of measurement.

This is achieved due to the fact that in the compensation accelerometer containing the sensor element, the angular position of which is fixed by the angle sensor, local positive feedback from the amplifier output to the input of the first voltage-current converter through the positive feedback phase detector and high-pass filter, local negative feedback communication from the output of the amplifier to the input of the second voltage-current converter through a negative feedback phase detector, as well as a comparator integrating the amplifier, Eversive binary counter, reference voltage generator, the outputs of which are connected to the inputs of the angle sensor and phase detectors of positive and negative feedback, which integrates negative feedback from the amplifier output to the adder input sequentially through the information inputs through the negative feedback phase detector, which integrates amplifier, signal rate limiter, comparator, level converter, a couple of standby synchronous generators, reversible binary counter ir, comparison circuit, trigger, electronic key, the input of which is connected to the output of the current generator, the second input of the comparison circuit connected to the output of the summing binary counter, and additional inputs of the comparator, waiting for synchronous generators, a reversing binary counter and summing binary counter connected to the auxiliary generator frequency, the outputs of the first and second voltage-current converters are connected to the input of the adder, the output of which is connected to the input of the torque sensor, as well as the output of the phase detector -negative feedback connected to an input of the second voltage-current converter via a differentiating element and the output of the reversible counter is a binary digital output compensating accelerometer.

Introduction to the local negative feedback of the differentiating link, and to the negative integrating feedback of the integrating amplifier and the rate limiter of the signal change allows increasing the measurement accuracy and expanding the passband and creating a compensation accelerometer with deviation astatism.

Figure 1 shows a functional diagram of a compensation accelerometer; figure 2 is a structural diagram of a compensation accelerometer; figure 3, 4 - transients in the compensation accelerometer with a single input exposure of a different sign (negative and positive, respectively).

The compensation accelerometer contains a sensor 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 amplifier 3. One output of the amplifier 3 is connected to the input of the phase negative detector 4 (FDOOS), and the other output of the amplifier 3 is connected to the input of the phase positive feedback detector 5 (FDOS). Additional inputs of the angle sensor 2, FDOOS 4, FDPOS 5 are connected to the output of the reference voltage generator 6 (GON). The output of FDOS 5 is connected to the input of the high-pass filter 7, the output of which is connected to the input of the first voltage-current converter 8. One of the outputs of the FDOS 4 is connected to the input of the differentiating link 9, the output of which is connected to the input of the second voltage-current converter 10. Outputs from the first and the second voltage-current converters 8 and 10 are connected to the input of the adder 11. Another output FDOOS 4 is connected to the input of the integrating amplifier 12, the output of which is connected to the input of the speed limiter signal 13. The output of the speed limiter from changing the signal 13 is connected to the input of the comparator 14, the output of which is connected to the input of the level converter 15, the outputs of which are connected to the inputs of a pair of standby synchronous generators (ZhSG) 16 and 17. The outputs of the ZhSG 16 and 17 are connected to the inputs of the reversible binary counter 18. The output of the reversible binary the counter 18 is connected to the input of the comparison circuit 19. Another input of the comparison circuit 19 is connected to the output of the summing binary counter 20. The output of the comparison circuit 19 is connected to the input of the trigger 21. The output of the trigger 21 is connected to the input of the electronic key 22, the other in One of which is connected to the output of the current generator 23. The output of the electronic key 22 is connected to the input of the adder 11. The output of the adder 11 is connected to the input of the torque sensor 24. Additional inputs of the comparator, ZhSG 16 and 17, the reversible binary counter 18 and the summing binary counter 20 are connected to the output auxiliary frequency generator 25.

The internal contents of the FDOOS, FDOS, comparator, waiting synchronous generators, a reversible binary counter, a comparison circuit, a summing binary counter, a level converter, a signal rate limiter, a filter, an integrating amplifier and voltage-current converters are given in the book: P. Horowitz, U. Hill The art of circuitry. M .: World, t 1-3, 1993.

Compensation accelerometer works as follows.

Under the action of acceleration on the sensing element 1, made in the form of a pendulum, the inertial moment acts. Under the influence of this moment, the sensor 1 deviates, which is detected by the angle sensor 2, the windings, the excitations of which are connected to the output of GON 6. The signal from the angle sensor 2 after amplification by amplifier 3 is fed to the inputs FDOOS 4 and FDPOS 5. Using FDOOS 4, FDPOS 5 and GON 6, the deviation phase of the sensitive element 1 is highlighted. At the output of FDOOS 4, the signal will always be in antiphase of the deviation of the sensitive element 1, and at the output of FDOS 5 in the phase of deviation 1. The signal from the output of FDOS 5 in the form of a voltage goes to the input of the filter top their frequencies are 7, and then to the input of the first voltage-current converter 8. The voltage from the output of FDOOS 4 is supplied to the input of the differentiating link 9, and then to the input of the second voltage-current converter 10 and, after converting to 10, to the input of the adder 11. High-pass filter 7, included in the positive feedback, is designed to eliminate the compensating effect of the positive negative feedback and stabilizes the parameters of the compensation accelerometer. The signal from FDOOS 4 in the form of a voltage is supplied to the input of the integrating amplifier 12. The voltage from the output of the integrating amplifier 12 is fed to the input of the speed limiter of the signal 13 and from the output 12 to the input of the comparator 14. In the comparator 14, the signal from the output of the speed limiter of the signal changes 13 with a signal isolated from a signal that is stable in frequency and amplitude from the output of the auxiliary frequency generator 25. If the signal from the output of the rate limiter of signal change 13 will be greater than the triangular voltage from the output and 25, the output of comparator 14 will be logic high, if less, then the output of the comparator 14 - a low logic level. The signal level from the output of the comparator 14 depends on the phase of the deviation of the sensing element 1 communication. The signal from the output of the comparator 14 in the form of a level is fed to the input of the level converter 15, and then to the inputs of the waiting synchronous generators 16 and 17, which, using the auxiliary frequency generator 25, give signals in the form of a pulse for each action of the input signal (from the output of the level 15 converter) equal to "1". The reversible binary counter 18 counts the single pulses coming from the output of the standby synchronous generator 16, and subtracts the pulses coming from the output of the standby synchronous generator 17. Reverse binary counter 18 represents positive information in the direct code, and negative in the additional code, and the conversion of the additional code is carried out by the comparison circuit 19 and the summing binary counter 20. After a logical comparison of the signals in the comparison circuit 19, the signal from the output 19 goes to the input of the trigger 21 and then in the form of a level at the input of the electronic key 22. The current generator 23 stabilizes the parameters of the electronic key 22. At the output 22 there will be pulses, the number of which is proportional to the binary code supplied to the input of the comparison circuit 19. A signal is received from the current winding of the moment sensor 24 the output of the adder 11 with the sign of the sign of the reversible binary counter 18. The output of the reversible binary counter 18 is the output of the digital code of the compensation accelerometer.

The introduction of local positive feedback with a high-pass filter and local negative feedback with a differentiating element into the compensation accelerometer, as well as negative integrating feedback with an integrating amplifier and a signal rate limiter, allows stabilizing the local feedback parameters, increasing the measurement accuracy and expanding the passband. In addition, the introduction of an integrating amplifier into the negative feedback circuit allows the creation of a compensation accelerometer with deviation astatism.

The simulation results of the compensation accelerometer with the width of the ambiguity zone of the threshold element included in the feedback equal to 0.01, are presented in figure 3 and figure 4 (respectively, when the input exposure is less than zero and more than zero). From the analysis it follows that the compensation accelerometer with implemented feedbacks is stable and a digital code is implemented in the integrating negative feedback, which is proportional to the input action.

Claims (1)

A compensation accelerometer containing a sensor whose angular position is fixed by an angle sensor, local positive feedback from the amplifier output to the input of the first voltage-current converter through a positive feedback phase detector and high-pass filter, local negative feedback from the amplifier output to the input of the second converter voltage-current through a phase detector of negative feedback, as well as a comparator, an integrating amplifier, a reversible binary counter, a gene a reference voltage ator, the outputs of which are connected to the inputs of the angle sensor and phase detectors of positive and negative feedback, characterized in that integrating negative feedback from the amplifier output to the adder input is introduced sequentially through the information inputs through the negative feedback phase detector, the integrating amplifier , signal change rate limiter, comparator, level converter, a couple of waiting synchronous generators, a reversible binary counter, a circuit is compared a trigger, an electronic key, the input of which is connected to the output of the current generator, the second input of the comparison circuit connected to the output of the summing binary counter, and additional inputs of the comparator, waiting for synchronous generators, a reversing binary counter and summing binary counter connected to the auxiliary frequency generator, outputs the first and second voltage-current converters are connected to the input of the adder, the output of which is connected to the input of the torque sensor, as well as the output of the negative phase detector tnoj connection coupled to an input of the second voltage-current converter via a differentiating element and the output of the reversible counter is a binary digital output compensating accelerometer.

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