ITTO990624A1 - DEVICE TO CARRY OUT NON-DESTRUCTIVE ANALYSIS ON STRUCTURE OF BUILDING MATERIALS. - Google Patents

Description

DESCRIPTION

of the patent for industrial invention

The present invention relates to a device for carrying out non-destructive analyzes on structures or building materials.

Devices are known for carrying out non-destructive tipc analyzes on building structures or materials in which an electronic unit cooperates with one (or more) sensors that can be coupled to a building structure / building material (for example a load-bearing wall, a partition wall, a beam , a pillar, a concrete block, a brick, etc.) and suitable to be used for the detection of static and dynamic characteristics of the structure / building material. For example, devices of the aforementioned type are known in which an electronic unit supplies impulsive signals to a first transducer for the emission of ultrasounds in the structure or building material and cooperates with a second transducer (or possibly with the same transducer) for the detection ultrasound transmitted through the building structure or building material. The electronic unit is able to analyze the received ultrasonic signal to detect static and dynamic characteristics (propagation speed, dynamic elastic modulus, attenuation of the structure or material) of the structure or building material.

Other devices are also known in which an electronic control unit cooperates with sensors (for example strain gauges, crack gauges, accelerometer inclinometers) suitable for detecting static characteristics of a building structure.

Each known type of device is therefore dedicated to carrying out a determined analysis and is provided with a certain number of specific sensors and an electronics dedicated to processing the signals generated by the sensors.

To carry out different analyzes, therefore, different devices are required with a corresponding increase in cost.

The object of the present invention is to provide a device for carrying out non-destructive analyzes on building structures or materials which is extremely flexible and therefore allows it to be easily reconfigured and / or enhanced to perform the functions of various traditional devices.

A further object of the present invention is to provide a device for carrying out non-destructive analyzes on structures or building materials that is able to use the computing, data management and visualization potential of an already existing processing unit, in particular a personal computer. For example, the computing potential of the personal computer can be advantageously used to carry out tomographic and spectral processing of the detected data.

The preceding object is achieved by the present invention since it relates to a device for carrying out non-destructive analyzes on structures or building materials of the type described in claim 1.

The invention will now be illustrated with reference to the attached drawings which represent a preferred non-limiting embodiment in which:

Figure 1 schematically illustrates a device for carrying out non-destructive analyzes on building structures or materials made according to the dictates of the present invention;

Figure 2 details a first electronic module of the device of figure 1;

Figure 3 details a second electronic module of the device of figure 1;

Figure 4 details a third electronic module of the device of figure 1;

Figure 5 illustrates a logic block diagram of operation of the device according to the present invention; And

Figure 6 illustrates an example of graphic representation provided by the device of the present invention.

In Figure 1, 1 indicates as a whole a device for carrying out non-destructive analyzes on structures or building materials.

The device 1 comprises an electronic unit 2 (shown schematically) housed in a portable container (not shown) and comprising an internal data communication line 5 (local BUS) communicating with a plurality of electrical connectors 7 (shown schematically), each of which is adapted to carry a respective electronic module 9 (schematically represented) making an electrical connection between lines of the BUS 5 and of output terminals of the module 9.

In a typical application example, the maximum number of modules 9 is eight; however it remains clear how different configurations are possible using a greater (or lesser) number of modules 9.

The local BUS 5 is able to allow bidirectional data communication between the various modules 9 and is also able to allow the modules 9 to be powered by providing each module with a stabilized power supply voltage Val generated by a power supply circuit 11. Preferably, but not exclusively, the power supply circuit 11 is adapted to convert a direct voltage supplied by a battery 13 (in particular a rechargeable type 7 battery, for example a nickel-cadmium battery) carried by the container (not shown) into a stabilized voltage ( for example ± 12 V and / or ± 5V) for the power supply of the modules 9. The power supply circuit 11 can also be adapted to convert an alternating mains voltage (220 Volt) into the stabilized voltage used for the power supply of the modules 9 and / or to recharge the battery 13.

Each module 9 is dedicated to a specific function and, in particular, the device 1 comprises a module 9a for transmitting and receiving data connected, through a communication channel 16, with a personal computer 18 (for example an IBM compatible personal computer ) comprising a central processing unit 19 and peripheral units such as video 20, keyboard 21, mouse 22 and printer 23. As will be clearer in the following description, the personal computer 18 supports a control SOFTWARE that can be used for managing the modules 9. The communication channel 16 can comprise any means suitable for allowing bidirectional data communication between the electronic unit 2 and the personal computer 18, for example a cable for serial / parallel communication, a telephone line, a radio bridge, etc.

The modules 9 also comprise instrumentation modules, for example an exciter module 9t communicating with transducers 25 which can be coupled to a building structure or a building material 26 (shown schematically) for the generation and transmission of ultrasonic signals u (t) in the building structure / in the building material 26 and a receiver module 9r communicating with transducers 29 which can be coupled to the building structure 26 for the reception of ultrasonic signals present in the building structure / in the building material 26.

Each instrumentation module can receive and send data and signals (analog and / or digital) to and from the local BUS 5; each instrumentation module can also be activated or deactivated according to the needs of the moment to obtain energy savings.

The building structure 26 generically comprises a complete building structure (for example a bridge) or a portion of a structure, for example a beam / masonry, a stone and / or decorative element, etc. The building structure 26 can also be made of various materials such as reinforced concrete, bricks, stone, metal, wood, etc. The device according to the present invention can also operate with a building material 26, ie with a portion of building material (a brick, a concrete block, a single beam, etc.) separated from the building structure and preferably analyzed in the laboratory.

With particular reference to Figure 2, the module 9a for data transmission and reception is illustrated in detail.

The module 9a comprises a microcontroller circuit 31 which communicates with the data line 5 through a separation circuit (current BUFFER) 33.

The microcontroller circuit 31 also communicates with the communication channel 16 through an interface circuit 35 adapted to allow the translation of data and the bidirectional data exchange between the microcontroller 31 and the communication channel 16.

The interface circuit 35 can comprise a plurality of interface circuits which can be used in an alternative way and are suitable for allowing data exchange according to different formats and / or according to different transmission modes; by way of non-limiting example, the interface circuit 35 may comprise:

■ an interface circuit 35s adapted to allow serial data communication; ■ an interface circuit 35p adapted to allow parallel data communication; ■ an interface circuit 35m (MODEM) adapted to allow the transmission of data through a telephone line (this circuit can be advantageously used if the personal computer 18 is located in a remote place with respect to the place where the electronic unit 2 is located; and

■ an interface circuit 35ir adapted to allow data communication by transmitting a beam of infrared radiation (this circuit can be advantageously used if the personal computer 18 is located at a short distance from the electronic unit 2).

The personal computer 18 is obviously provided with a suitable interface circuit 18i (Figure 1) adapted to receive the data coming from the communication channel 16 and adapted to translate such data into the format that can be used inside the personal computer 18 itself.

The microcontroller circuit 31 also cooperates with an EEPROM memory 37 and a FLASH memory 38; preferably, but not exclusively, the FLASH memory 38 can be internal to the microcontroller circuit 31. It is however clear that the flash memory 38 may not be present.

Typically the EEPROM memory 37 contains calibration data of the electronic unit 2 while the FLASH memory 38 (if present) contains program data of the microcontroller 31.

The microcontroller circuit 31 performs the following main functions:

■ reception and storage of measurement data fed out on the local BUS 5 by the various instrumentation modules 9;

■ translation of the measurement data supplied at the output of the various instrumentation modules 9 on the BUS 5 into a communication protocol that can be interpreted by the personal computer 18; and ■ transferring the translated data to the interface circuit 35 for their transmission to the personal computer 18.

The microcontroller circuit 31 performs a series of auxiliary functions including:

■ generation of reference signals for the various instrumentation modules 9;

■ generation of control signals for the various instrumentation modules 9;

■ recording and management of the setting parameters from the various instrumentation modules 9 (this recording can be carried out on the EEPROH 37 memory); And

■ detection of the instrumentation modules 9 inserted in the respective connectors 7 (the aforesaid function, also called PLUG & PLAY, allows the microcontroller circuit 31 to always know how many and which instrumentation modules 9 communicate with the local BUS 5 and are active).

Analog reference signals (for example a voltage) can also be generated by a circuit 42 communicating with the local BUS 5.

With particular reference to Figure 3, an instrumentation module 9t of the exciter type is shown, suitable for supplying single pulses of voltage Vpk to the transducer 25 for generating the ultrasonic signals u (t).

The 9t module comprises a continuous / continuous converter circuit 50 (DC / DC converter) adapted to convert an input voltage Vin (typically the maximum voltage supplied by the power supply circuit 11) into an output voltage Vout whose value can be adjusted according to of driving signals SEL_V fed to the converter circuit 50 by a control circuit 51; in particular, the converter circuit 50 is adapted to supply at the output several discrete voltage values, for example 5 Volt, 10 Volt, 50 Volt and 100 Volt.

The module 9t further comprises an energy storage circuit 52 connected in input to the output of the converter circuit 50 and adapted to store a predefined quantity of electric charge generated by the circuit 50; the stored electric charge value can be adjusted as a function of control signals SEL_Q fed to the storage circuit 51 by a control circuit 53; in particular, the storage circuit 52 comprises a plurality of individually selectable capacitors (not shown) having different capacities, each capacitor being adapted to be powered by the voltage Vout to store a predetermined quantity of charge.

A voltage multiplier circuit 55 is interposed between the output of the energy storage circuit 52 and the input of a damper circuit 57 whose output is in turn connected to the transducer 25.

The voltage multiplier circuit 55 is able to realize, following a driving signal TRIG, the discharge of the energy contained in the energy storage circuit 52 by supplying at the output a single voltage pulse Spk supplied to the transducer 25 (for example of the type resonant) cooperating with the damper circuit 57. Conveniently, but not exclusively, the voltage multiplier circuit 55 comprises a voltage step-up transformer (not shown) which can be connected by closing an electronic switch (for example a field effect transistor - not shown) with a charged capacitor (not shown) of the energy storage circuit 52.

The Spk pulse is a high voltage pulse (conveniently voltage of the order of 1000-1500 volts peak) whose energy is a function of the charge stored in the circuit 52 and whose voltage is a function of the voltage supplied by the circuit 50.

The driving signal TRIG is supplied to the circuit 55 by a control circuit 59. A further control circuit 61 cooperates with the damper circuit 57 (of known type, for example of the resistive type) which can be switched on / off on the basis of a driving signal EN / DIS coming from the control circuit 61 itself.

A plurality of driving signals are thus generated by the control circuits 51, 53, 59 and 61 for the configuration and control of the circuits 50, 52, 55 and 57. The control circuits 51, 53, 59 and 61 in turn they respond to command data from the local BUS 5.

In particular, by means of command data coming from the local bus 5 and applied to the respective control circuits 51, 53, 59 and 61, the following can be regulated:

■ the pulse voltage (by means of command data fed to the control circuit 51); ■ pulse energy (by means of command data supplied to control circuit 53);

■ the instant of application of the pulse (by means of command data fed to the control circuit 59); And

■ any damping applied to the pulse (by means of command data fed to the control circuit 61). With particular reference to Figure 4, the receiver module 9r adapted to receive ultrasonic signals present in the building structure 26 is illustrated in detail.

In particular, the receiver module 9r comprises: ■ a coupling circuit 61a connected at the input with the transducer 29 and able to provide, alternatively, a direct or alternating coupling with the transducer 29 on the basis of a DC / AC driving signal coming from local BUS 5;

■ an adjustable attenuator circuit 63 input connected to the coupling circuit 61a and controlled by means of pilot signals SEL_GAIN coming from the local BUS 5;

■ a pre-amplifier and impedance adapter circuit 64 connected in input to the output of the attenuator circuit 63 and having fixed gain (for example 0 dB or -40 dB); the circuit 64 also has the function of an impedance separator;

■ an insertable low-pass filter 65 (or more insertable low-pass filters connected in cascade) connected in input with an output of the pre-amplifier circuit 64 and controlled by driving signals coming from the local BUS 5;

■ a linear measurement amplifier 68 input connected to the output of the filter 65 and having an output connected to a first input 66a of a first selector circuit 66;

■ a logarithmic amplifier 69 connected in input to the output of the filter 65 and having an output connected to a second input 66b of the selector circuit 66. - the first selector circuit 66 is controlled by signals coming from the local bus 5; ■ a digitizer circuit 71 connected in input with the output of the selector circuit 66 and communicating, through a control logic 73, with the local bus 5.

In this way, the digitizer circuit 71 can receive in input, according to the input selected by the selector circuit 66:

■ the output signal to filter 65 subjected to linear amplification (input 66a); And

■ the output signal to filter 65 subjected to logarithmic amplification (input 66b).

The outputs of the linear amplifier 68 and of the logarithmic amplifier 69 also communicate with the first and second inputs 74a, 74b of a second selector 74 which communicates at the output with a trigger circuit 75 cooperating with the control logic 73. The second circuit selector 74 is controlled by signals coming from the local bus 5.

The trigger circuit 75 is adapted to detect the first significant peak of the received signal in order to calculate the time (flight time) elapsed between the generation of the ultrasonic signal (in the transducer 25) and the detection of the signal transmitted through the building structure / the building material. Preferably the detection of the first peak is carried out on the signal fed at the output of the logarithmic amplifier 69 (selector 74 arranged in the position 74b) since the logarithmic amplification allows to better highlight the presence of the first peak; however, it remains clear that, if the signal supplied at the output of the transducer 29 has a high value and clearly distinguishable peaks, the detection of the first peak can also be carried out on the signal supplied at the output of the linear amplifier 68 (selector 74 arranged in the position 74a).

Figure 5 illustrates the block diagram of the operations carried out by the personal computer 18 operating with the electronic unit 2.

Initially, a block 100 is reached which controls an initialization phase during which a data exchange is carried out with the electronic unit 2 to detect how many and which active electronic modules 9 are connected to the local BUS 5; as previously mentioned, this function is performed with the aid of the microcontroller circuit 31 which controls which modules are connected to the local BUS by transferring the information on the modules to the personal computer 18 through the communication channel 16.

Block 100 also controls the presentation on the video 20 of the information relating to the modules connected to the local BUS 5; this information can, for example, be represented graphically by icons (not shown) which represent the active modules connected to the local BUS 5.

Block 100 is followed by a block 110 which makes it possible to choose a module (or more modules) for carrying out a certain type of non-destructive type of measurement. For example, the pair of modules 9t, 9r for measuring the transmission characteristics of the building structure / building material 26 can be selected (with manual command given by means of a mouse 22 or keyboard 21).

Block 110 is followed by a block 120 which makes a video presentation of the setting parameters of the selected module (or modules).

This presentation is conveniently carried out in a graphical environment (Figure 6) by means of which various control elements can be represented which are suitable for modifying the setting parameters of the module; for example, if modules 9t, 9r are selected, control elements can be selected (for example linear control elements whose cursor can be positioned using the mouse 22) with which they can be adjusted (module 9t):

■ the output voltage Vout of the converter circuit 50 (control element C1);

■ the electric charge value stored in the circuit 52 (control element C2);

■ the instant of application of the voltage pulse (control element C3); And

■ the presence of any damping (control element C4).

It is also possible to modify the setting parameters of the module 9r such as the type of coupling introduced by the circuit 61a, the attenuation introduced by the circuit 63, the number of low pass filters 65 inserted and the type of amplification (linear or logarithmic) to be applied to the signal. fed at the filter outlet 65.

Block 120 is followed by a block 130 which detects the user commands (given, for example, by means of the mouse 22) for modifying the setting parameters; these user commands are translated into suitable command signals by a block 140 following block 130 and sent, through the communication channel 16, to the electronic unit 2 where the microcontroller 31 responds to the command signals generating the command data that generate the control signals SEL_V, SEL_Q, TRIG, EN / DIS (module 91) for the control of the converter circuit 50, of the energy storage circuit 52, of the voltage multiplier circuit 55 of the damper circuit 57 and the driving signals for the control of the coupling circuit 61a, of the attenuator circuit 63, of the filter 65 and for the selection of the type of amplification (linear or logarithmic),

In this way the setting parameters of modules 9a and 9r are modified remotely from the personal computer 18.

Following the operations of blocks 130, 140 (or parallel to them) a block 150 receives the measurement data coming from the instrumentation modules 9. The instrumentation modules 9 in fact send the results of the measurements on the local BUS 5 where such the results are transferred to the microcontroller 31 which translates them into a suitable format and transfers them, through the communication channel 16, to the personal computer 18 which performs (block 150) the presentation of the results of these measurements.

With regard to modules 9t, 9r, the following results can be presented:

■ crossing time of the ultrasonic pulse generated by the voltage pulse Vpk;

■ digitalized waveform FO of the ultrasonic signal transmitted by the building structure 26; And

■ spectral attenuation and / or alteration.

Block 150 is followed by a block 160 which verifies whether the measurement in progress is to be considered finished; in the negative (measurement still in progress) block 160 is followed by block 120 for a further modification of the parameters and for carrying out a new measurement. In the positive case (measurement completed) block 160 is followed by a plurality of individually selectable blocks including:

* a block 170 for the analysis of the results of the measurement previously carried out;

■ a block 180 for activating a plurality of utility functions;

■ a block 190 for activating a plurality of program and data access protection functions; And

■ a block 195 for printing and / or consulting the user manual of the device 1.

Blocks 170, 180, 190 and 195 are followed by a block 200 which awaits a user command for the end of the procedure; in the negative case it returns to block 160, otherwise the program is exited.

In use, a user places the electronic unit 2 near the building structure / building material 26 on which the non-destructive measurements are to be carried out and connects, for example, the transducers to the building structure / building material 26. In particular, the transducers 25 and 29 are arranged on the building structure 26 and a procedure for selecting the measurement modules (block 110) to be used is then started by means of the personal computer 18. Following the selection of the module (or modules), and therefore following the selection of the type of measurement to be carried out, the setting parameters of the modules are set (blocks 130 and 140). The setting of the parameters is carried out, in a graphic environment (figure 6), on the personal computer 18 through which remote control signals are sent which pass on the communication channel 16 and on the local BUS 5 reaching the electronic unit 2 where they are modified for example, the settings of the converter circuit 50, of the energy storage circuit 52, of the voltage multiplier circuit 55 and of the damper circuit 57. The settings of the receiver module 9r can also be changed. In the example of embodiment relating to modules 9t and 9r, a selected capacitor (not shown) of the circuit 52 is charged with a predetermined voltage Vout and then discharged, at a predetermined instant, on the voltage multiplier which produces a voltage pulse at the output. Vpk applied, with a possible damping, to the transducer 25 which in turn produces an ultrasonic pulse applied to the building structure 26. The ultrasonic pulse passes through the building structure / building material 26 and is received by the transducer 29; the entity of the ultrasonic signal received depends on the transmission characteristics of the building structure / building material which are in turn a function of static and dynamic structural characteristics. Hollow cracks or fractures in the building structure / building material 26 prevent good transmission of the ultrasonic signal. The signal received by the transducer 29 is optionally filtered, pre-amplified, filtered and subsequently can be amplified in a linear or logarithmic way. The trigger circuit 75 receives in input a signal on which the first pic is detected to perform (in a known way) the calculation of the time interval (flight time) between the emission of the signal by the transducer 25 and the reception. of the signal itself by the transducer -29 in order to calculate the propagation speed of the ultrasonic signal in the building structure / building material 26. The signal received and amplified in a linear or logarithmic way can also be digitized and the waveform digitized Fo can be represented on video 20.

The measurement results can then be analyzed.

From the above the advantages of the device according to the present invention are clear since:

■ the modular construction using the local BUS 5 on which various modules 9 can be arranged allows the creation of a flexible instrument that can be easily reconfigured and / or enhanced by adding and / or replacing modules; ■ the electronic unit is controlled in an automated way by the personal computer 18 by means of a software (or an equivalent hardware) which performs the functions of figure 5 - a real "virtual instrument" is thus obtained through which it is possible to set the parameters measure and perform a non-destructive measure by operating on the personal computer 18;

■ the device according to the present invention also has a low cost since all the control part is resident on the personal computer 18 which is of a commercial type, and can be used for other purposes thus allowing a convenient amortization of costs; and ■ all the storage, data processing and graphic presentation potentials present on a personal computer are also exploited.

Finally, it is clear that modifications and variations can be made to the device described without however departing from the scope of protection of the present invention.

R I V E N D I C A Z I O N I

1.- Device for carrying out non-destructive analyzes on structures or building materials characterized by the fact that it includes:

an electronic unit (2); and

a processing unit (18) communicating with said electronic unit (2) through a communication channel (16);

said electronic unit (2) comprising:

- at least one local data line (5);

- a plurality of electronic modules (9,9a, 9r, 9t) connectable (7) to said local data line (5);

said plurality of electronic modules comprising at least one instrumentation module (9r, 9i) adapted to carry out a non-destructive measurement on a structure or on a building material (26); said measure being at least settable by means of remote commands coming from said processing unit (18);

said instrumentation module (9r, 9i) being able to supply measurement data to said processing unit (18).

2.- Device according to Claim 1, characterized in that said processing unit comprises a personal computer (18).

3.- Device according to Claim 1 or 2, characterized in that said processing unit comprises:

- display means (120) adapted to present, on a video unit (20) of said processing unit, (18) setting parameters of at least one selected module (9r ,: 9t) (110);

- setting means (130, 140) which respond to user commands (22) for changing the setting parameters; said setting means (130,140) being able to translate the user commands introduced into command signals sent, through said communication channel (16), to said electronic unit (2) which responds to said command signals by generating the respective signals piloting, (SEL_V, SEL_Q, TRIG, EN / DIS and SEL_GAIN) for the control of said modules (9r, 9t).

4.- Device according to Claim 3, characterized by the fact that said display means (120) are adapted to provide on said video unit (20) a graphic presentation by means of which control elements (C1-C5) which can be used to modify said setting parameters.

5.- Device according to any one of the preceding claims, characterized in that the said processing unit comprises:

- monitoring means (150) of measurement data coming from the instrumentation modules (9) suitable for receiving and translating said measurement data by presenting, on a video unit (20) of said processing unit, the results of the measurements carried out by modules themselves.

6.- Device according to any one of the preceding claims, characterized in that the said processing unit (18) comprises initialization means (100) suitable for carrying out a data exchange with the said electronic unit (2) to detect the active electronic modules (9) connected to the local data line (5).

7.- Device according to any one of the preceding claims, characterized in that said modules comprise a module (9a) for data transmission and reception provided with a microcontroller circuit (31) communicating with said local data line (5) and with the communication channel (16) through interface means (35); said microcontroller circuit (31) being able to perform at least one of the following functions:

■ reception and storage of measurement data fed out on the local data line (5) by the instrumentation modules (9);

■ translation of the measurement data fed out from the instrumentation modules (9) into a communication protocol that can be interpreted by said processing unit (18); And

■ transfer of translated data towards said interface means (35) for their transmission towards the processing unit (18).

8.- Device according to any one of the preceding claims, characterized in that said instrumentation modules (9) comprise a module of the exciter type (9t) suitable for supplying single voltage pulses (Vpk) to a first transducer (25) for generation of the ultrasonic signals u (t); said first transducer (25) being coupled to a building structure (26) or to a building material (26).

9, - Device according to Claim 8, characterized in that said exciter module (9t) comprises:

a continuous / continuous converter circuit (50) adapted to convert an input voltage (Vin) into an output voltage (Vout) whose value can be adjusted as a function of driving signals (SEL_V) related to said remote commands coming from said processing unit (18);

an energy storage circuit (52) connected in input to the output of said converter circuit (50) and adapted to store a predefined quantity of electric charge; the stored electric charge value being adjustable as a function of driving signals (SEL_Q) correlated to said remote commands coming from said processing unit (18); And

a voltage multiplier circuit (55) interposed between the output of said energy storage circuit (52) and said first transducer (25); said voltage multiplier circuit (55) being able to perform, following a driving signal (TRIG) related to said remote commands coming from said processing unit (18), the discharge of the energy contained in the energy storage circuit ( 52) supplying said first transducers (25) with a single voltage pulse (Spk). 10.- Device according to any one of the preceding claims, characterized in that said instrumentation modules (9) comprise a module of the receiver type (9r) cooperating with a second transducer (29) for the detection of ultrasonic signals present in the building structure or in the building material (26).

11.- Device according to claim 10; characterized in that said receiver-type module (9r) comprises:

at least one amplifier circuit (68, 69} receiving in input a signal generated by the second transducer (29);

a trigger circuit (75) communicating at the input with the output of said amplifier circuit and able to detect the first significant peak of the signal fed to its input in order to calculate the time elapsed between the generation of the ultrasonic signal and the detection of the signal transmitted through the building structure / building material.

12. A device according to Claim 11, characterized in that said amplifier circuit (68, 69) comprises a linear amplifier (68).

13. A device according to Claim 11, characterized in that the said amplifier circuit (68, 69) comprises a logarithmic amplifier (69).

14.- Device according to Claim 11, characterized in that it further comprises, arranged between said second transducer (29) and said amplifier circuit (68, 69), at least one of the following circuits:

- a coupling circuit (61a) connected in input with the said second transducer (29) and adapted to provide, alternatively, a direct or alternating coupling with the second transducer (29) on the basis of driving signals (AC / DC) related to said remote commands coming from said processing unit (18);

an adjustable attenuator circuit (63 receiving in input a signal coming from said second transducer (29) and controllable by driving signals (SEL_GAIN) correlated to said remote commands coming from said processing unit (18);

- a pre-amplifier circuit (64) receiving in input a signal coming from said second transducer (29);

- at least one low-pass filter of the insertable type (65) receiving in input a signal coming from said second transducer (29).

Claims (1)

15.- Device for carrying out non-destructive analyzes on structures or building materials, substantially as described and illustrated with reference to the attached drawings,