RU2124741C1 - Ultrasound computer-aided station - Google Patents

Abstract

FIELD: seismic reconnaissance equipment for investigation of rocks, concrete and other materials. SUBSTANCE: device has vibrator, which is connected to generator of sounding pulses, receiver of vibrations with preliminary and power amplifiers, analog-to-digital converter and computer as device for control, processing and storing information. In addition device has clock oscillator, optical isolation unit, and signal processor. Clock oscillator is connected to circuit for starting signal processor and generator of sounding pulses, which is supplied by high- voltage power supply. Optical isolation unit is connected between clock oscillator and generator of sounding pulses to achieve galvanic isolation. Signal processor, which is connected to computer through interface, sets modes of power amplifier, analog-to-digital converter and is equipped with synchronization unit which is connected to clock oscillator, and buffer memory unit which stores data received from analog-to-digital converter and results of processing. EFFECT: increased functional capabilities. 1 dwg

Description

 The invention relates to seismic exploration and can be used to study rocks, concrete and other materials.

 Known borehole digital geoacoustic station [1], containing a source and receiver of elastic oscillations with an amplifier, a generator, control, processing and recording devices, an analog-to-digital converter, an information input unit, synchronization and control units, an initial installation circuit, three memory units, three a counter, the output of each of which is connected to the first input of the corresponding memory block, an arithmetic-logic device, a display memory block and a digital-to-analog converter and an electron connected in series o-ray tube, while the input of the source of elastic vibrations is connected to the output of the generator, the output of the receiver of elastic vibrations is connected in series with the input of the amplifier and an analog-to-digital converter, the output of which is connected to the input of the processing device, the outputs of which are connected to the inputs of the arithmetic device and registration devices and control, the outputs of the latter are connected to the inputs of the generator, processing device, analog-to-digital Converter and the second inputs of the memory block, the third inputs of which are connected to the output ohm of the arithmetic device, and the outputs with the input of the arithmetic-logic device, the outputs of the information input unit are connected to the inputs of the arithmetic device of the synchronization unit, the outputs of which are connected to the inputs of the initial setup circuit and the control unit, and the outputs of the latter are connected to the input of each counter, to the second input of each from which the output of the initial installation circuit is connected.

 The disadvantages of this device are the inability to fully digitally process the signal, including its accumulation and filtering, insufficient noise immunity and efficiency.

 Also known is a borehole digital geoacoustic station [2], which contains a borehole source of elastic vibrations connected to a generator and downhole receivers of elastic vibrations with amplifiers, an analog-to-digital converter, a control and recording device, two memory units, a digital computer, synchronization and input units information. The station is additionally equipped with a start-up circuit, a ground-based transmitter and receiver, a digital-to-analog converter, interfaces of a radiation system and a reception system, a time-amplitude analyzer, a multiplexer, additional downhole receivers with amplifiers, a decoder and a video animation device, the generator input being connected to the output of the starting circuit, the input of which is connected to the output of a ground-based receiver connected by radio wave communication with a ground-based transmitter, the input of which is connected to the output of a digital-analogue an educator whose input is connected to the output of the radiation system interface, the input of which is connected to the first output of the synchronization unit, the first input of which is connected to the output of the reception system interface, the input of which is connected to the output of the second memory block, the input of which is connected to the output of the analog-to-digital converter, input which is connected to the output of the time-amplitude analyzer, the input of which is connected to the output of the multiplexer, to the input of which borehole receivers of elastic vibrations are connected through amplifiers, the second input of the synchronization unit The input is connected to the first output of the control device, the input of which is connected to the first output of the information input unit, the second output of the synchronization unit is connected to the first input of the first memory unit, the second input of which is connected to the output of the decoder, the input of which is connected to the second output of the information input unit, second output the control device is connected to the second input of the digital computer, the first output of which is connected to the input of the video animation device, the second output of which is connected to the registration device.

 They coincide with the essential features of the claimed invention — an elastic oscillation source connected to a generator with a start-up circuit, elastic oscillation receivers with signal amplifiers, an analog-to-digital converter, a computer as a device for controlling, processing and recording information. Therefore, this analogue, as the closest to the claimed, is taken as a prototype.

 The disadvantages of the prototype are the lack of the ability to process signals (digital filtering, accumulation, etc.) in the "real time" mode, which leads to a decrease in noise immunity, as well as the lack of the possibility of operations with floating point numbers, which limits the dynamic range of signal registration, the hardware dependence of the length digitized signal from RAM size.

 The aim of the invention is to improve the signal-to-noise ratio. Acceleration of the processing of information and the depth of the survey, which is especially important when solving engineering and geophysical problems in conditions of buildings under construction or in operation.

 This goal is achieved by the fact that in an ultrasonic computerized station containing an elastic oscillation source connected to a probe pulse generator, an elastic oscillation receiver with preliminary and main amplifiers, an analog-to-digital converter and a computer as an information control, processing and recording device, an external clock a generator, an optocoupler isolation unit and a signal processor, the clock generator being located on the block of analog devices and connected to the signal trigger circuit Nogo process and sounding pulse generator, which is powered by a high voltage source; the optocoupler isolation unit, which is also located on the block of analog devices, couples the clock generator and the probe pulse generator and ensures their galvanic isolation, and the signal processor, located on the digital processing and control unit and connected through the interface to the control computer, sets the modes of the main amplifier, analog -digital converter and is equipped with a synchronization unit associated with a clock generator on the block of analog devices, and a buffer memory in which data is accumulated, digits together with the analog-to-digital converter and processing results.

 The block of analog devices includes a clock generator, optocoupler isolation, an amplifier-driver, a probe pulse generator, a matching device, a unit of preliminary amplifiers, attenuators, and analog filters.

 The digital processing and control unit includes a synchronization unit, a main amplifier, an analog-to-digital converter, a buffer memory, a signal processor, and a computer.

 The drawing shows a functional diagram of an ultrasonic computerized station.

 The station contains a clock generator 1, which through an optocoupler isolation 2 and an amplifier-driver 3 is connected to a probe pulse generator 4 connected through a matching device 6 to a source of elastic vibrations 7; n ultrasonic vibration receivers 9 are connected to a node of preliminary amplifiers 10 connected through attenuators 11 and analog filters 12 to programmable main amplifiers 13, the outputs of which are connected to an analog-to-digital converter 14, which is connected through a buffer memory (RAM) 15 to the signal processor 16 and Computer 17. The input of the synchronization node 8 is connected to the clock generator 1, and the output to the signal processor 16.

 As a source of elastic vibrations 7 and a receiver of elastic vibrations 9, piezocrystalline and piezoceramic transducers can be used. The generator 4 can be made in the form of a pulsed thyristor generator, powered by a high voltage from a power supply 5.

 As a computer 17 can be used mini-computers such as "Note book", convenient for operations in the field. The signal processor 16, the programmable main amplifier 13, the analog-to-digital converter 14 and the buffer memory 15 can be made on the basis of known standard elements and nodes.

 Ultrasonic computerized station operates as follows.

 The clock generator 1 block of analog devices generates pulses that synchronize the operation of the system. The pulses are fed to the optocoupler isolation unit 2, at the output of which there is an amplifier-driver 3. The generated trigger pulse is used to open the thyristor generator of probing pulses 4, the high voltage for which comes from the high-voltage generator of the power supply unit 5. The probe pulse is supplied through the matching unit 6 to the piezoelectric transducer 7.

 The pulse of the clock generator is also fed to the input of the synchronization unit 8 of the digital processing and the control unit. From this moment, the process of registering the signal coming from the piezoelectric transducer 9 begins. The signal is amplified by a preliminary amplifier 10. The gain of the preliminary stage is set by a manual step attenuator 11. Next, the signal is filtered by an analog filter 12. The coefficient of the main amplifier 13 is set programmatically. An analog-to-digital converter 14 converts the amplified signal to the channel number specified by the program. The result of digitization is placed in the buffer RAM 15 and processed by the signal processor 16 (DSP). The considered process is repeated as many times as indicated in the accumulation counter of the control program. At the request of the host computer program 17, the processing results are transmitted for visualization and storage on a magnetic computer medium.

 The block of analog devices and the block of digital processing and control are powered by the block 18. The general power supply of the station can be carried out both from an alternating current main 220 V and from a direct current source + 12V.

 Sources 7 and receivers 9 of elastic vibrations can be located both on the surface of the object and inside it, for example, in wells and boreholes.

 The use of the signal processor 16 can significantly increase the efficiency and speed of digital signal processing, expand the possible set of manipulations with the signal, such as various types of signal accumulation, its digital filtering. All this leads to a significant increase in the useful signal against the background of interference, increases the size of the base of possible ultrasonic measurements.

 The use of optocoupler isolation improves the reliability of the device, since it prevents the possible hit of high voltage and impulse noise on low-voltage computer circuits and DSP.

 The use of an autonomous clock generator provides a wide selection of station operating modes: in standby, single, periodic mode, which expands the capabilities of the station.

Sources of information
1. USSR author's certificate N 1242881, G 01 V 1/40 dated 01/02/1985.

 2. RF patent N 2050012, G 01 V 1/40 dated 03.24.1992.

Claims (1)

 An ultrasonic computerized station containing an elastic oscillation source connected to a probe pulse generator, an elastic oscillation receiver with preliminary and main amplifiers, an analog-to-digital converter and a computer as a device for controlling, processing and recording information, characterized in that a clock generator is additionally introduced into it , an optocoupler isolation unit and a signal processor, the clock generator being connected to the probe generator through the optocoupler isolation and the driver amplifier pulses connected through a matching device to a source of elastic vibrations, n ultrasonic vibrations receivers are connected to a preliminary amplifier assembly connected through attenuators and analog filters with programmable main amplifiers, the outputs of which are connected to an analog-to-digital converter, which is connected via a buffer memory to a signal processor and a control computer, while the input of the synchronization node is connected to the clock generator, and the output to the signal processor.