Hardware-software device for multichannel conversion and recording of analog signals
FIELD: electronic engineering.
SUBSTANCE: for each channel device has digital signal converter, block for setting conversion digitization frequency, conversion level adjustment block, block for transferring electric signals to physical values, block for observing converted signals, block of precision of signal conversion, block of signal conversion time, block for disabling unused channels, block for synchronization of analog signals, visualization block, converted signal recording block. Device allows to convert signals of different levels, to change digitization frequency and conversion time, to disable unused channels, transfer sensors signals to physical values with consideration of sensors scales, observe signals at different scales, appropriate to levels of converted signals, to measure precision of recording of converted signals.
EFFECT: higher efficiency.
The invention relates to measurement devices, namely, devices carrying out the registration of signals from electrical sensors, and can be used for recording the various electrical signals.
In many industries there is a need for reception of analog signals with electrical sensors. For this purpose established the analog and digital devices to record all of them analog signals.
Using an electric sensors produce many dimensions, in particular to measure the pressure in the flow and pulsation. So, for example, electrical sensors, pressure pulsations are widely used in the testing of aircraft engines. Similar devices used for testing and debugging compressors.
The tendency to increase the load-speed compressor and a corresponding increase in peripheral speed and rotation speed leads to expansion of the frequency range of measurements. In particular, when conducting research aimed at improving the efficiency of the speed compressors and having in its composition stage supersonic flow in relative motion, it is necessary to improve the accuracy and information content of the measured parameters during the measurements, use the AMB low-inertia electric sensors with a frequency range up to 100 kHz, have the appropriate modern devices to collect analog data, digital conversion and subsequent processing of the received data. So, when visualization of the flow structure in the flow part of the compressor by measuring the pressure pulsation fast-response sensors with the subsequent construction of the Isobar require simultaneous multi-channel registration of coming with them to analog signals.
Known Analog magnetic device A2-1214/A2-914, manufactured by SONY Magnescale Inc., which is a 14-channel magnetic recorder and records the signals on the tape.
The disadvantage of this device is the necessity of using additional blocks for digital conversion of the analog signal when performing secondary processing. In addition, this magnetic device has a frequency range of 0...40 kHz, which limits the scope of its application.
Known Multichannel digital device MSX16”, which provides “Multilevel digital diagnostic system for GTD”, presented in patent U.S. No. N 1006, G 01 B 7/16, from 27.03.1990, collect analog data from strain gauges or other electrical sensors.
The disadvantage of this technical solution is the limit of the frequency range (Δf=0...25 kHz) nevozmojnosti synchronous polling of sensors used.
The closest technical solution to the proposed and adopted for the prototype is a Digital device SIR-1000W”, catalog PRODUCT CATALOG 2003", which has multiple input and allows polling of electrical sensors, the sampling rate is reduced in proportion to the number of channels used. It has a frequency range of 160 kHz with 4-channel input, 80 kHz with 8-channel input and 40 kHz with 16-channel input.
The main disadvantage of this device is the limitation on the sampling rate and its decrease with increasing numbers of channels, as well as the inability of the organization synchronous read analog data from a large number of sensors. The absence of these features does not allow to use this device to build instantaneous contours of pressure in the channels of the rotating impeller of the compressor, and also does not allow simultaneous survey of fast-response pressure transducers when used for the study of unsteady and unstable processes, for example, in the aircraft engine and the compressor.
The objective of the proposed technical solution is to increase the efficiency of the device by ensuring accuracy and high sampling rate conversion and registrazioneworld analog signals at their simultaneous intake with fast-response sensors.
The technical result is achieved in the inventive hardware-software device that allows multi-channel conversion of analog signals simultaneously received from the signal sources. This hardware-software device is provided with a control unit of the level conversion signal for each channel, the block frequency sample rate conversion of incoming signals, the block transfer of electrical signals into physical quantities, the unit of observation for the converted signals, block precision conversion signal, the block length of signal conversion, block off unused channels, block reception of signals, the synchronization unit analog signals, while the power level control signal for each channel is connected to a unit change of sampling rate conversion, which is connected to the power monitor signal and to block off unused channels, and the unit conversion accuracy of the signals connected to unit specify the duration of the conversion signals, and a unit of translation of electrical signals into physical quantities connected with the registration unit signals, and the synchronization unit analog signals.
Ripple static and total pressures measured motionless mA is inertinite sensors in the speed of the compressor, have broadband, polyharmonically composition. The frequency of the first harmonic of the AC signal pressure is equal to the repetition frequency of the blades, the frequency of the second and subsequent harmonics of the signal reflects the nature of pressure changes in the interscapular channels, the structure of the traces and disturbances in the flow generated by the rotation of the impeller. For analysis of the nature of the processes in the interscapular channels is sufficient to have information in a spectrum of frequencies including the fifth harmonic signal. When the rotational speed of the rotor 200 Hz and the number of blades at level 50 this corresponds to a frequency of 100 kHz.
Currently recording of analog signals with fast-response pressure sensors are produced using a multi-channel magnetic devices having the frequency range of 40 kHz (with dynamic error ±12%), which gives a satisfactory averaged and instantaneous paintings currents, determined by the contour of the pressure in each interscapular channel impellers of the compressor.
The construction of isolines of pressure produced using complex programs tied to specific computers with multi-channel analog-to-digital Converter with reduced sampling rate. Processing sensor data produced by introducing successively analog signal registered by each of the sensors. Taco is the way of introduction information is a lengthy process and allows construction of contour only after testing. In addition, this method of collecting and processing information requires additional system clock, which reduces the possibilities for the introduction of the useful signal.
To transition to a more modern system of collection and processing of low-inertia data with a higher accuracy and resolution, you need a device that provides high resolution digital conversion of an analog signal and input it into the computer.
The duration of one revolution of the rotor is hundredths and thousandths of a second, and the time it takes one blade, 100 times less, and to monitor the detachment of the boundary layer, having a thickness commensurate with the thickness of the profile, you must have several points on the time interval Δt=1...3 ISS. During the measurements, as experience shows, it is impossible to predict in advance the form of a signal from a particular sensor. Therefore, the sampling frequency must be high enough to ensure a high quality signal conversion of any form. In the study of the flow stream speed compressors to increase the information content of the measurement system and get a more complete view about the changes in the structure of the flow in separate channels of the impeller of the compressor when changing the PE the ima work on the flow and momentum, check signal must provide the necessary number of points for each step interscapular channel impeller of the compressor.
The structure of the flow is multi-zone and contains jumps seals, and formed and descending vortices in the separation of the flow inside the channel and track for the blades. When digital recording of an analog signal at each point along the path of the compressor, this condition must be fulfilled. This is especially important when unstable flow blades, for example, near the border of steady work, as in this case, it is necessary to consider the instantaneous flow patterns, and the averaged pattern of the flow give the wrong idea about the processes occurring in the wheel.
In this regard, for the study of unsteady effects must synchronous readout of the signal from the sensors in order to avoid misconceptions about the changes in current, which may occur due to phase shift.
The claimed hardware-software device for multichannel conversion of analog signals is a standard card that provide signal conversion with 12-bit resolution. Connecting such devices to a personal computer allows you to get multi-channel Converter and recorder analog signals. Synchronization circuit boards carry out the special program.
The claimed hardware-software device for multi-channel conversion and reception of analog signals allows you to:
- convert the signal at various levels;
to change the sample rate conversion in the range Δf=1000...1000000 Hz;
- translating electrical impulses into physical values taking into account the static calibrations of each of the sensors;
- to observe the signal in different scales, corresponding to the level of the converted signal;
to change the accuracy of the recording of the converted signal;
to change the duration of the conversion;
- disable unused channels;
register for signal excluding a DC component.
All these functions are provided with special software blocks, the action of which is initiated by the appropriate buttons.
Figure 1 shows a diagram of the inventive hardware and software devices for multichannel conversion of analogue signals.
Figure 2 is a view of the signal from the sensor current impulses generated by serial passage of turnovers, converted using the hardware and software of the device.
Figure 3 shows the signals from the two fast-response pressure sensors that are installed above the working blade with successive passage of the jet, the x adjacent channels, and converted using the hardware and software of the device.
Figure 4 shows the signals appearing in the gauge is full and the gauge static pressure in the nozzle to determine the velocity uctuation, converted using the hardware and software of the device.
Figure 5 shows a view of a signal from the pulse sensor repetition frequency of the blades of the impeller of the compressor caused by consecutive passage of two adjacent blades and converted using the hardware and software of the device.
Hardware-software device for multi-channel conversion and reception of analog signals, which are depicted in figure 1, contains sensors 1-12 analog signals, block 13 frequency sample rate conversion of incoming signals, the block 14 of the regulation of the level conversion signal for each channel, block 15 transfer of electrical signals into physical quantities, unit 16 monitoring converted signals, block 17 precision conversion signal, the block 18 the duration of the conversion signal, the block 19 to disable unused channels, the block 20 registration signals, block 21 synchronization of analog signals. While the sensors are analog signals 1-12 connected to the block 13 frequency sample rate conversion post the surrounding signals, unit 14 regulation of the level conversion signal for each channel, as well as block 15 translating electrical impulses into physical quantities and unit 16 monitoring converted signals, block 17, which specifies the accuracy of the transformation, which, in turn, is connected with the block 18 the duration of the conversion and unit 19 to disable unused channels, as well as block 20 registration signals and block 21 synchronization signals.
Hardware-software device for multichannel conversion of analogue signals is as follows:
Before you begin set the parameters of our conversion, such as sampling rate, number of points in implementations, the number of decimal places in the numbers after the conversion. Getting started units connected to the computer, perform by pressing “start”, and then produce a rendered view of the signals from the connected measuring electrical appliances. If necessary, make the change of signal level and corresponding change of the settings of the scales in the Windows of the oscilloscope (not shown). In accordance with the tasks of the research and nature of the detected processes, choose the mode of work of conversion signals that meet the requirements:
- regard or disregard the constant component;
- take into account or not the coefficients that convert electrical signals into physical values;
- produce a switching signal.
Record file made in Microsoft Excel in dialog mode.
The claimed hardware-software device for multi-channel conversion and reception of analog signals using ready analog-to-digital Converter and a personal computer for simultaneous multi-channel conversion and reception of analog signals for subsequent secondary processing allows contouring of the pressure in the flow part of the compressor for the study of unsteady flow patterns. At the same time extend the frequency range of the measurement system. Also, this device allows for a study of the structure of flow in compressors with high speed and high frequency blades. Moreover, it outperforms the previously used device register analog data, for example, using an analog multichannel magnetic device and processing the received data with the help of a special computer, the operating frequency range exceeding more than 25 times and in as many times exactly converted the analog I signal, and digital multi-channel recording of signals of any electrical sensors produce synchronously.
Hardware-software unit (APU) for multi-channel conversion and reception of analog signals, including a signal source, a digital signal Converter, a unit of rendering the converted signal, the recording unit of the converted signal, the block of secondary processing, characterized in that it is equipped for all channels by block frequency sample rate conversion of incoming signals, the control unit of the level conversion signal for each channel, the block transfer of electrical signals into physical quantities, the unit of observation for the converted signals, block precision conversion signal, the block length of signal conversion, block off unused channels, block reception of signals, the synchronization unit analog signals while the power level control signal for each channel is connected to a unit change of sampling rate conversion, which is connected to the power monitor signals and block off unused channels, the block precision conversion signal is connected to the unit set the duration of the conversion signals, and block transfer electric is practical signals in physical quantities connected with block reception of signals and a synchronization unit analog signals.
SUBSTANCE: device has base address selector, registers, delay elements, elements of OR groups, OR elements, memory block, reverse counter, comparator.
EFFECT: higher speed of operation.
FIELD: measuring technologies.
SUBSTANCE: method includes setting tolerance for controlled parameter, measuring physical value, associated with said controlled parameter, with numeric characteristic of its value, then measured value is compared to its tolerated values (tolerances for controlled parameter), and decision concerning level of match of measurement results to tolerances for parameter is taken, when determining tolerance for controlled parameter an affiliation function is set for phrase "parameter on basis of measurements in tolerance", and during taking of decision trustworthiness of phrase is evaluated, expressed in non-precise measure, as value of affiliation function, matching value of measured parameter.
EFFECT: higher trustworthiness.
SUBSTANCE: device has control trigger, random pulse generators, block for forming program of functioning of modeled multimode system, working modes and technological mode blocks, operation time counters, random pulses generators, OR block, orders counters.
EFFECT: broader functional capabilities.
SUBSTANCE: system has nine registers, four address selectors, triggers, AND elements, OR elements and delay elements.
EFFECT: higher speed.