RU2378984C2 - Device for control and evaluation of physiological processes - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to devices of medico-biological purpose, intended for registration and evaluation of fast-proceeding physiological reactions, emerging as response to produced stimuli. Device contains microcontroller, analogue-digital converter (ADC), first commutator, sensors of breast breathing, abdominal breathing, skin-galvanic response, arterial pressure, cardio-vascular activity, sensor of motor activity, power unit, preliminary amplifiers, signal amplifiers, filters, first and second digital-analogue converters (DAC), tool amplifier and unit of connection with personal computer, supplied with galvanic attenuator. Via amplifiers and filters sensors are connected with corresponding inputs of commutator whose controlling input is connected with first microcontroller bus, and output - with first input of tool amplifier. Second input of tool amplifier is connected to output of first DAC, third input - to output of second DAC, and output - to ADC input. Inputs of first and second DAC and group of inputs-outputs of ADC are connected with second microcontroller bus, whose third bus is connected to unit of connection with personal computer. Additional channel has possibility of connection to its input of face mimics sensor, piezoplethysmogram or variable component of skin-galvanic response and includes second electronic commutator, to whose outputs subchannels of processing of signals from corresponding sensor are connected. First subchannel includes successively connected preliminary amplifier and filter, second subchannel - preliminary amplifier, filter, signal amplifier and additional filter, and outputs of subchannels via third electronic commutator are connected to first commutator input. Controlling input of third commutator is connected with microcontroller.

EFFECT: registration of maximal number of physiological parametres and ensuring objectivity of obtained information.

2 cl, 2 dwg

Description

FIELD OF THE INVENTION

The invention relates to medicine, in particular to devices for biomedical use, designed to record and evaluate the fast-flowing physiological reactions of a person arising in response to the incentives presented to him (questions, objects, photographs, etc.). The invention can be used to implement a psychophysiological method for identifying hidden information during surveys, forensic psychophysiological examinations, during proceedings on the facts of abuse, corruption, theft. The proposed device is a functionally complete unit and is used for receiving, amplifying, converting, and transmitting for further processing to a personal computer the physiological parameters of the tested person: tonic and phase components of electric skin resistance, chest and abdominal breathing, blood pressure, cardiovascular activity (plethysmogram, photoplethysmogram), motor activity (tremor and facial expression sensor).

State of the art

To conduct psychophysiological studies in medicine and other fields, various devices for monitoring and analyzing human physiological reactions are widely used, which include polygraphs, voice stress analyzers, strain gauges, etc. These devices record and process human responses to stimuli that they perceive.

Devices for controlling, storing and transmitting registered information are known from foreign patent literature, see, for example, EP 0212278. The known device comprises a microprocessor, a decoder, an information receiving unit, an analog-to-digital converter (ADC), a switch, a heart rate sensor, a shaper signal. This device, however, due to the small number of analyzed physiological parameters has a low reliability.

From US Pat. No. 4,940,059, a polygraph with improved registration of a cardiac signal is known, which uses blood pressure information along with a heart rate.

From international application WO 03/057003 a non-invasive polygraph based on optical analysis is known. The device generates a series of pulses in the laser, infrared range, these pulses are reflected from the subject, fed to a receiver connected to the processor, analyzed, information is displayed.

One of the latest foreign developments is the device disclosed in publication US 2007270659, this device allows you to remotely detect false information in the information received from the test subject using at least one physiological parameter transmitted at a distance. The interpreter uses a polygraph to evaluate.

Among domestic developments, one can distinguish the device according to patent RU 2010326, which uses a whole range of parameters: the parameters of the dynamics of cardiovascular activity, respiration, and galvanic skin reaction. The device contains a microprocessor, an information receiving unit, sensors of physiological parameters.

Closest to the present invention is a device for monitoring and evaluating physiological parameters according to patent RU 2203614. The known device contains a microcontroller, an ADC, a switch, sensors for chest respiration, abdominal respiration, galvanic skin reaction, blood pressure, cardiovascular activity, a sensor of motor activity, power supply, pre-amplifiers, signal amplifiers, filters, digital-to-analog converters (DACs), instrumental amplifier and PC interface, sleep adjoint galvanic isolation. The sensors through amplifiers and filters are connected to the corresponding inputs of the switch, the control input of which is connected to the first bus of the microcontroller, and the output to the first input of the instrument amplifier, the second input of the instrument amplifier is connected to the output of the first DAC, the third input to the output of the second DAC, and the output to the input of the ADC, the inputs of the first and second DACs and the group of ADC inputs and outputs are connected to the second bus of the microcontroller, the third bus of which is connected to the interface unit with a personal computer. This device allows you to obtain data on the presence in the received information of false information with a sufficiently high reliability. However, the known device uses a limited number of parameters, it does not provide the ability to select parameters for evaluation. In this regard, the reliability of the conclusion obtained using this device is insufficient.

Summary of the invention

The problem to which the invention is directed is to create a device for monitoring and evaluating physiological processes using the maximum number of physiological parameters, selecting parameters, in particular during the test, for subsequent evaluation by degree of significance and providing undoubted objectivity to the conclusion obtained with its help.

In addition, the invention allows for operation both in stationary and in the field.

In addition, the invention improves the reliability of the information obtained by connecting channels for obtaining information about the different components of one parameter.

The technical result is achieved due to the fact that in the device for monitoring and evaluating physiological processes containing a microcontroller, an ADC, a first switch, sensors for chest respiration, abdominal respiration, galvanic skin reaction, blood pressure, cardiovascular activity, a motor activity sensor, a power supply , preamplifiers, signal amplifiers, filters, the first and second DACs, instrumentation amplifier and a personal computer interface unit equipped with galvanic isolation, while the sensor ki through amplifiers and filters are connected to the corresponding inputs of the first switch, the control input of which is connected to the first bus of the microcontroller, and the output to the first input of the instrument amplifier, the second input of the instrument amplifier is connected to the output of the first DAC, the third input to the output of the second DAC, and the output - to the ADC input, the inputs of the first and second DACs and the group of ADC inputs and outputs are connected to the second bus of the microcontroller, the third bus of which is connected to the interface unit with a personal computer, an additional cable is used with the possibility of connecting a facial expression sensor, a piezoplethysmogram sensor or a galvanic skin reaction to its input and including a second electronic switch, to the outputs of which are connected signal processing subchannels from the corresponding sensor, the first subchannel includes a preamplifier and a filter connected in series, the second one is a preliminary an amplifier, a filter, a signal amplifier and an additional filter, and the outputs of the subchannels through a third electronic switch, the control input connected to the mic controller, connected to the input of the first switch. The facial expression sensor is equipped with elastic straps with an adjustable length ending with latches for mounting the sensor on the person’s head, and a cap that is able to contact the person’s head and, through the spring, act on the button connected to the piezoelectric element, the conclusions of which are the output of the sensor.

Description of drawings

The invention will be better understood from the following description with reference to the drawings, in which:

figure 1 presents the functional diagram of the device,

figure 2 shows a General view of the sensor facial expressions.

Description of a preferred embodiment of the invention

The device for monitoring and evaluating physiological processes 1 is designed to work in conjunction with a personal computer (not shown), which provides processing and display of the received information, its recording, storage, printing of test results.

The device 1 contains a microcontroller 2, an ADC 3, a first switch 4, a chest breathing sensor 6, an abdominal breathing sensor 5, a galvanic skin reaction sensor 7, a blood pressure sensor 8, a cardiovascular activity sensor 9, a motor activity sensor 10, a power supply 11 , pre-amplifiers 12-19, signal amplifiers 20-22, filters 23-33, first and second DACs 34 and 35, instrumental amplify 36 and a unit for interfacing 37 with a personal computer equipped with galvanic isolation. Sensors 5-10 through pre-amplifiers 12-16 and 19, filters 23-29 and 33 and signal amplifiers 20 and 22 are connected to the corresponding inputs of the first switch 4, the control input of which is connected to the first bus of the microcontroller 38, and the output to the first input of the instrument amplifier 36, the second input of the instrumentation amplifier 36 is connected to the output of the first DAC 34, the third input is to the output of the second DAC 35, and the output is to the input of the ADC 3, the inputs of the first and second DACs 34 and 35, and the group of inputs / outputs of the ADC 3 are connected to the second bus 39 of microcontroller 2, the third bus 40 of which is connected ana interface unit 37 with a personal computer. An additional channel introduced into the device according to the invention has the ability to connect to its input a facial expression sensor 41, an additional piezoplethysmogram sensor or an additional sensor for skin-galvanic reaction (not shown). The additional channel includes a second electronic switch 42, to the outputs of which sub-channels of signal processing from the corresponding sensor are connected. The first subchannel includes a preamplifier 17 and a filter 30 connected in series, the second channel includes a preamplifier 18, a filter 31, a signal amplifier 21 and an additional filter 32. The outputs of the subchannels through the third electronic switch 43 are connected to the input of the first switch 4. The control input of the third switch 43 is connected to the output of the microcontroller 2.

Sensor 41 facial expressions is designed to record indicators of motor activity of the muscles of the face of a person. The sensor 41 is equipped with elastic straps 44 with adjustable length, ending with latches 45 for mounting the sensor 41 on the head of the subject, and a cap 46 that can contact the person’s head, and through a spring (not shown) to act on the button 47 connected to the piezoelectric element, the conclusions of which are the output of the sensor 41. A cable with a connector is connected to the housing of the sensor 41. The pressure perceived by cap 46 is transmitted through the spring to button 47. An electrical signal proportional to the derivative of the force exerted on the button is output from the sensor via a cable. The elements of the sensor housing 41 are made of an aluminum alloy with a protective oxide decorative coating.

Instead of a face expression sensor 41, a piezoelectric plethysmogram or tremor sensor or a skin-galvanic reaction sensor (a variable component) can be connected to an additional channel.

The sensor 10 of motor activity is designed to record indicators of motor activity of a person. It consists of two sensor elements mounted under the legs of the chair, and a connecting cable with a connector. The body of the sensor element is made of two steel plates separated by a washer of porous rubber. The basis of the sensor element is a piezoelectric element glued to the inner surface of one of the metal plates. To transfer the force to the piezoelectric element from the opposite plate, a rubber disk is glued to it. Sensor elements are connected in parallel.

The skin-galvanic reaction sensor 7 is designed to record changes in skin resistance. The sensor 7 is fixed with fasteners on the fingers of the hands of the subject.

The sensors for chest 5 and abdominal 6 breathing are structurally identical and consist of a housing in which there is a variable capacitor and an electronics board, two levers, as well as clamps connected to the levers by elastic belts. The latches are connected by a chain, with the help of which the sensor can be fixed on the chest cage of any size.

The blood pressure sensor is a pear with an exhaust valve, with a tee attached to it, connecting tubes with a pneumatic connector and a rubber cuff.

The piezo plethysmogram sensor is designed to register peripheral vascular blood flow indices. The sensor is equipped with a fastener for mounting on a person’s finger. The pressure perceived by the cap is transmitted through the spring to the button connected to the piezoelectric element. An electrical signal proportional to the derivative of the force applied to the button is output through the cable. The photoplethysmogram sensor is mounted on the finger in the same way. Perceived by the photodiode mounted on the sensor body, the infrared light flux penetrating the peripheral blood vessels in the finger is converted into an electrical signal proportional to the light power of this flux and is output from the sensor through a cable connecting it to the corresponding channel of the device.

The device is used as follows.

The outputs of the sensors through the amplifiers 13-17 and 20-22 and the filters are alternately connected through the switch 4 to the input of the instrumental amplifier 36 (an amplifier with an adjustable gain). From the output of the instrumentation amplifier 36, the signal is fed to a 12-bit ADC 3.

The instrumental amplifier 36 allows you to match the amplitude of the signals of the sensors 5-10 and 41 with the input range of the ADC 3. In addition, the amplifier 36 serves to compensate for the constant component of the signals of the sensors, for which voltage from the first DAC 34 is supplied to one of the inputs.

The first switch 4, the ADC 36, the first and second DACs 34 and 35 are controlled by the microcontroller 2 via standard buses 38, 39. The gain and offset values for each channel are transmitted to the microcontroller 2 from a personal computer via channel 40. The microcontroller 2 performs primary processing of the sensor signals and then it transmits digital information from the computer via channel 40, which includes the interface unit 37 with the personal computer, made according to the optocoupler galvanic isolation circuit. Power is supplied to the device circuit through an isolating converter 44, providing galvanic isolation, from the power source. To monitor the health of the sensors and connecting cables, a test signal is generated that is sent to the channels of all sensors except the blood pressure sensor 8. The blood pressure channel processes the signal of the cardiovascular activity indicator. The signal from the pressure sensor 8 is fed to the input of the pre-amplifier 19, through a filter 33 and a signal amplifier 22 to the first switch 4 and the microcontroller 2 for further processing. The channel of motor activity (tremor) processes the signal of the indicator of motor activity. The signal from the sensor 10 through the amplifier 16 and the active second-order filter 29 passes to the microcontroller 2 for further processing. The plethysmogram channel processes the signal of the cardiovascular activity indicator. The signal from the sensor 9 passes through an amplifier 15, an active filter of the second order 27, passes for further processing to the microcontroller 2. An additional universal channel allows the connection of a sensor of a variable component of the skin-galvanic reaction or a piezoelectric sensor (sensor 41 facial expressions, an additional plethysmogram sensor, motor activity ) The choice of the type of sensor can be carried out by the operator using the service program directly in the process or before the test. The signal from the selected sensor is fed to the second electronic switch 42 and then divided into two subchannels, each of which is adapted to process the signal from the corresponding sensor. The signal from the piezoelectric sensor, for example, the facial expression sensor 41, is processed in the first subchannel. He goes to the pre-amplifier 17, which performs the coordination of the high resistance of the sensor and input circuits with subsequent stages. Next, the signal passes through an active second-order filter 30 and enters through the switches 43 and 4 for further processing. The second subchannel is designed to process a signal from a skin-galvanic reaction sensor. A voltage proportional to the skin resistance passes through the preamplifier 18, the first-order low-pass active filter 31, the signal amplifier 21, through the second-order low-pass active filter 32, the third and first switches 43 and 4 for long-distance processing.

Before turning on the device, appropriate sensors are placed on various parts of the body of the subject to record physiological parameters. The skin-galvanic reaction sensor 7, made in the form of two electrodes, is fixed on the index ring fingers of one of the hands. Sensors of chest and abdominal breathing 6 and 5 strengthen on the chest and in the diaphragm. The plethysmographic sensor 9 is fixed on the middle finger. The sensor of motor activity 10 is strengthened under the chair on which the subject is seated. Blood pressure sensor 8 is placed on the arm above the vessel.

In the process of testing, the test subject is presented with a series of test questions at regular intervals. These questions relate to inclinations, abilities, personal qualities and have a neutral, verification and control character. Upon presentation of control questions, the answer to which does not correspond to the real situation, an emotional outburst occurs, which after a short period of time is expressed in an abrupt change in indicators. Measurements are made continuously and information about them is transmitted through the processing circuit to microcontroller 2 and then to a personal computer. The personal computer accumulates and processes the received data and, in accordance with the program laid down, prints out a preliminary report and a polygram.

The microcontroller 2 receives and processes information from a personal computer according to the exchange protocol. In addition, it provides storage of gain and bias values for each measuring channel, power management, selection of the measuring channel, reception of the conversion results and the output of the conversion results to a personal computer, as well as the generation of a test signal to monitor the health of sensors and connecting wires.

The personal computer is implemented as a package of application programs integrated into a single environment and providing the following functions: input of signals of controlled physiological processes and their visualization (or their parameters) in the form of graphs in real time, saving the entered data for subsequent work with them, viewing polygrams (saved data in graphic form) in the dialogue mode, output to the printing device of the received polygram (in whole or in fragments), simultaneous viewing of surveys, input from the keyboard of additional markers in a real-time system, mathematical data processing and generation of the examination protocol in tabular form, viewing, correction and printing of the generated protocol, creating a library of questionnaires and their use in the process of conducting a psychophysiological examination, automatic selection of questions, having the greatest emotional significance for the subject, writing and subsequent editing by the operator of the conclusion of the survey tions, printing.

Industrial applicability

The device’s circuitry uses standard elements, known and described in the patent literature, sensors (except for the original ones disclosed here) and blocks. All elements of the device circuit are manufactured industrially. The galvanic isolation unit is made on the optocoupler channel AD307-FD256, the model of the 6000 series CAMBASIC is used as a microcontroller. It is not a problem for a specialist to make and use the presented device, taking into account the information above.

Therefore, the invention meets the condition of industrial applicability.

Claims (2)

1. A device for monitoring and evaluating physiological processes, containing a microcontroller, an analog-to-digital converter (ADC), a first switch, sensors for chest respiration, abdominal respiration, galvanic skin reaction, blood pressure, cardiovascular activity, a motor activity sensor, a power supply, preamplifiers, signal amplifiers, filters, first and second digital-to-analog converters (DACs), instrumentation amplifier and a personal computer interface unit equipped with galvanic isolation while the sensors through amplifiers and filters are connected to the corresponding inputs of the first switch, the control input of which is connected to the first bus of the microcontroller, and the output is from the first input of the instrument amplifier, the second input of the instrument amplifier is connected to the output of the first DAC, the third input to the output of the second DAC and the output is to the ADC input, the inputs of the first and second DACs and the group of ADC inputs and outputs are connected to the second bus of the microcontroller, the third bus of which is connected to the interface unit with a personal computer, which differs the fact that an additional channel is introduced into it with the ability to connect a facial expression sensor, a piezoplethysmogram sensor, or a sensor of a variable component of the skin-galvanic reaction, including a second electronic switch, the outputs of which are connected to the first and second subchannels of signal processing from the corresponding sensor, while the first subchannel includes a pre-amplifier and a filter connected in series, the second includes a pre-amplifier, a filter, a signal amplifier and an additional filter, and the outputs subchannels through the third electronic switch, the control input connected to the microcontroller, connected to the input of the first switch. 2. The device according to claim 1, characterized in that the facial expression sensor includes elastic straps with an adjustable length ending with latches for mounting the sensor on the subject’s head, and a cap that can contact the subject’s head and, through the spring, act on the button connected to the piezoelectric element whose outputs are the output of the sensor.

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