SU1420383A1 - Method of determining velocity of ultrasound propagation in bone tissue through soft tissue - Google Patents

Abstract

The invention relates to non-destructive testing by ultrasound methods and can be used in medicine for monitoring the state of human bone tissue and for testing in flaw detection of materials and structures in a liquid medium. The purpose of the invention is to increase the productivity of determining the speed of ultrasound propagation in bone tissue through soft tissues. The method consists in emission of ultrasonic vibrations by the first group of transducers located at the same distance from each other on one straight line, into the bone tissue through soft tissues, received by the second group of transducers located at the same distance from each other on the same straight line, ultrasound signals, which pass through bone tissue and soft tissues, determine the difference between the arrival times of ultrasound signals averaged over all successive pairs of transducers of the second group, Torah group of transducers and receiving the first group, and determining the average of all consecutive pairs of the transducers of the first group of the difference of arrival times of the ultrasonic signals, and determining the velocity of ultrasound propagation in the bone by the formula given in the description. 1 il. i

Description

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ISOPRESIS refers to the non-disruption of its control by ultrasonic methods and can be used in medicine for monitoring the state of human bone tissue by measuring the speed of propagation of ultrasonic oscillations in bone tissue through soft tissue and for flaw detection during control of materials and structures in liquid medium.

The purpose of the invention is to enhance the functionality and increase the productivity of changes in the speed of races of the country ()} and ultrasound in the bone tissue through soft tissues.

The drawing shows a block diagram of a device for implementing the proposed method.

The device contains multielement 11) emerase. 1, 1, mounted on the study (1 () 2, serially connected unit 3, unit 4 of the excitation generators and transmitting multiplexer 5, serially connected to the multiplex multiplexer 6, unit 7 of forming time intervals, digital meter 8 time and 1 intervals. storage unit 9. api | 1) methico-L (:

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Indicator 11. The outputs of the transmitting multiplexer 5 and the inputs of the receiving multiplexer 6 are connected to two groups of N conversion elements of the multi-element converter 1. The additional outputs of the control unit 3 are connected to the inputs of the storage unit 9, the transmitting multiplexer 5 and the receiving multiplexer 6.

The method is carried out as follows.

The converter elements of the multielement converter are located on the same straight line. Each group contains N transducers located at one pack distance d from each other, and at each measurement on the test object is used as an emitter when sounding in one direction and as a receiver when sounding in the opposite direction. In this case, the receiver is fixed at the receiver | x 1nn over all successive pairs of presses) braz (; difference, for the first rpyiHibi and for the second group of long-transducers.

Speed of ultrasound is determined by iio for0

not the speed of ultrasound propagation in the bone tissue; VT is the propagation speed of ultrasound on soft tissues.

Control unit 3 generates the boreiness of rectangular voltage pulses shifted in time relative to each other by the same interval. The delays between the pulses are chosen so as to ensure the propagation of the front of the object being excited in the object under study (T) (2 ultrasonic waves at an angle, close to the IMM to the optimum angle of ultrasound injection into the object under study 2. Control sequence and pulses starts with the appropriate delays the excitation generators located in the block 4 of the excitation generators. The voltage pulses from the output of the block 4 of the excitation generators arrive at the input of the transducer 1, its multiplexer B. The multiplexer 5 receives sigpal Y, which acts throughout the entire time of the first measurement.At the signal Y, the first group of converter elements of the multi-element converter 1 is connected to the transmitted multiplexer 5, which excites voltage from the excitation generator unit 4.

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the expander 1 generates ultrasonic vibrations that propagate in the object under study 2 and are received by the second group of transducer elements of the multi-element transducer 1. The multi-element transducer 1 converts the ultrasonic vibrations into electrical signals that go to the receiving multiplexer 6. The presence of the control the input of the receiving multiplexer 6 signal Y ensures the passage of electrical signals from the first and last converting elements of the second group of transducer nyh elements 7 forming the input block of time slots. The latter generates two rectangular pulses from the two electrical signals that are listening to it, the time distance between which corresponds to the difference in arrival times of the electrical signals. From the output of the time interval shaping unit 7, the measured time interval enters the measuring instrument of 8 time intervals, which determines the digital value time interval t between the time of arrival of the signal from the first and N-ro converting elements of the second group of converting elements of the multi-element transform 1. The digital value is recorded in the storage unit 9 and is stored with Fi n, -m, u) the end of the operation cycle of the device, iaievi the 3-engraving unit again generates r1 () 1.-lep ters of the right angle niji.x UMiiy. The voltage-shifted ibcoBs that trigger the excitation generators located in block 4 of the excitation generators. The excitation pulses from block 4 of the excitation generators through the transmit multiplexer 5 are sent to many. 1st converter 1. With this signal; | Y is not generated and the second group of transducer glands of the multi-element transducer 1 is connected to block 4 of the excitation generators. Multi-element transducer 1 generates ultrasonic vibrations that propagate in the object under study 2 and are received by the first group of transducer elements of the multi-element transducer 1. Multi-element transducer 1 converts ultrasonic fluctuations in the electrical signals that are fed to the receiving multin: 1exor 6. At the same time, on the control signal during the reception (about the multiplexer 6, the Y signal from the control unit 3 is absent, which ensures the passage of electrical signals: 1s from the first and the last transformative elements to the input of the time interval formation unit 7. The time interval formation unit 7 forms It has two electrical signals, a measurable time interval, which is measured from an 8 time interval meter. A digital 8 time interval meter determines a digital value of a time interval with. the arrival of the signal from the first and N-ro converting elements of the first group of converting elements of the electronic-electronic converter 1. The digital value is recorded in the zeromized block 9 and stored in it until the end of the device operation cycle. In storage unit 9, the velocity of ultrasound propagation in human tissues (VV 1540 m / s), the number N of transducer elements in each rpyinie, and the distance d between adjacent transducers in the group are prerecorded. According to the signal from the control unit 3, these values, as well as the measured time intervals "and T, are read into the arithmetic logic unit 10, which is calculated

with q; 2 T-, 4j ×

Гг, 4-1Г (1) -уЬ - (-т-) п - (- T-) J

where the rate of ultrasound propagation in the bone tissue;

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melts averaged over all pic, arctic. For the first pair of transducers of the first group, the difference f, the arrival times of ultrasonic signals according to the formula t, 1), the difference C of the arrival times of the ultrasonic signals averaged over all serial pairs of transducers of the second group, F e / (N - 1) and the speed Vx of the ultrasonic oscillations in the bone tissue according to the formula (I). The calculated value of the speed x of ultrasonic vibrations in the bone tissue is displayed on the digital indicator 11, after which the operation cycle of the device ends. Then the progressive cycle of operation of the device is repeated many times.

Claims (1)

Invention Formula A method for determining the speed of paccipocT-ultrasound wound in bone tissue through soft tissues, which consists in emitting ultrasonic pulsed oscillations, receiving ultrasonic vibrations transmitted through bone and soft tissues, and determining the speed of ultrasound propagation in the bone tissue by the time of ultrasound propagation and a predetermined speed of ultrasound propagation in soft tissues, characterized in that, in order to expand the functional capabilities and increase the productivity of speed measurements ultrasound propagation, emit ultrasonic pulse oscillations by the first group of N transducers located at the same distance d from each other on the same straight line, receive the transmitted oscillations by the second group of N converters. those located at the same distance d from each other on the same direct, fix the difference t of times of ultrasonic oscillations travel averaged over all serial pairs of transducers of the second group, emit ultrasonic and impulse oscillations by the second group of N transforms ovateley take oscillation past the first group of N transducers, fixed averaged over all successive pairs of transducers of the first group difference H, vre.men arrival of the ultrasonic vibration and at speed. 1 ultrasound in the bone tissue is determined by 1 / speed of ultrasound propagation in soft tissues.