Method and device for detecting motion of object

Abstract

The invention relates to a method and a device for detecting object motion, which adopt an inertia force sensor with preset strain and convert signals output by the sensor into information units with different physical characteristics through multiple modulation and a frequency division network. The measuring system is sensitive, stable, small in size, anti-interference, low in power consumption, high in signal-to-noise ratio and good in damping and frequency response characteristics. Heart pulsation and respiratory movement can be detected without touching a human body, important human body vital movement information can be obtained in a very simple and convenient mode, and a new technical approach is provided for medical diagnosis and health monitoring. Tiny vibration of buildings and machines can be detected, and a simple and convenient tool is provided for quantitatively knowing the environment; some abnormal information of crustal movement can be found, and a beneficial detection means is provided for disaster prevention and natural science research.

Description

Technical Field

[0001] This invention pertains to measurement technology, and specifically relates to a method and apparatus for detecting the motion of an object. Background Technology

[0002] Motion parameters are important physical quantities of universal interest in the natural world and human activities. Currently, various methods and devices exist for detecting object motion, such as methods utilizing electromagnetic induction and moving-coil sensors; methods using the relative displacement between a permanent magnet and a magnetic sensing element to generate signals and Hall effect sensors; methods measuring changes in capacitance or inductance accompanying motion and capacitive or inductive sensors; and methods directly contacting piezoelectric films to sense motion information and contact motion detectors, etc. Researchers have been continuously striving to find more sensitive, stable, wider frequency response, and lower power consumption and cost-effective methods and devices for detecting object motion. Summary of the Invention

[0003] The purpose of this invention is to provide a sensitive, reliable, low-power, and low-cost technical solution for detecting object motion information, so as to meet people's needs in medical diagnosis and monitoring, safety monitoring, earthquake early warning, and related scientific research and engineering activities.

[0004] The technical solution of the present invention is to use a piezoelectric film (2) attached to the surface of an elastic strip (1). One end of (1) is fixed, and the other end of (1) can vibrate freely. An object (3) is attached to the end of (1) that can vibrate freely. Under the action of gravity on (3), (1) bends, and the end of the strip (1) attached to (3) undergoes displacement perpendicular to the surface of (1). The ratio of the displacement to the distance between the two ends of (1) is greater than 0.05. In this continuous deformation state of (1), (2) together with (1) and (3) constitutes a sensor (4) for acquiring object motion information, such as... Figure 1 (1) The distance between the two endpoints is a. Under the gravity of (3), the vertical displacement of the freely movable endpoint of (1) is b, b / a > 0.05. Figure 2 The elastic strip (1) has a width between 0.1 micrometers and 10 centimeters, a length between 0.2 micrometers and 20 centimeters, and a thickness between 0.1 micrometers and 0.5 millimeters; (1) is a strip of polymeric organic material, or a strip of metallic material, or a cantilever beam made of semiconductor material, such as Figure 3 The electrical signal output by sensor (4) enters the frequency converter (5), which changes the frequency, and then enters the audio amplifier (6). The speaker (7) or headphones (8) are connected to (6) to emit sound information that can be perceived by hearing and is related to the motion state of the object, such as... Figure 4The electrical signal output by the sensor (4) may enter a precision detector (9) composed of an operational amplifier, semiconductor diode, resistor, and capacitor to separate the motion information, such as... Figure 5 The electrical signal output from the precision detector (9) enters one or more bandpass filters (10) with different bandwidths and center frequencies connected in parallel at the input. The (10) decomposes the motion information output from (9) into one or more specific bandwidth spectral information. The output of (10) is connected to an oscilloscope (11), a digital voltmeter (12), or a voltage comparator (13) with a light-emitting diode display to display the signal characteristics of a specific frequency band, such as... Figure 6 (9) The output electrical signal may enter the signal amplitude modulator (14). (9) is connected to one input terminal of the signal amplitude modulator (14), and the audio signal generator (15) is simultaneously connected to the other input terminal of (14). At the output terminal of (14), the signal obtained by amplitude modulation of the motion information output by (9) on the audio carrier of a specific frequency is obtained. This signal emits sound related to the motion information through the speaker (16) or headphones (17), such as Figure 7 (9) The output electrical signal is either input to an oscilloscope (18), a digital voltmeter (19), or a voltage comparator (20) with a light-emitting diode display, to directly display the acquired object motion information, such as... Figure 8 .

[0005] Compared with existing technologies, the method and device provided by this invention have good frequency response and damping characteristics, high sensitivity, low power consumption, and anti-interference. They can detect heartbeats and respiratory movements without contacting the human body, and can monitor minute vibrations of buildings and machines in a simple way. They can also help detect certain abnormal information of earth movement, and provide a useful measurement tool for medical monitoring and diagnosis, engineering and technical activities, and natural science research. Attached Figure Description

[0006] Figure 1 A schematic diagram of the changes in the spatial shape of the sensor before and after the attachment of the object (3). The top is before the attachment (3) and the bottom is after the attachment (3).

[0007] Figure 2 A side view showing the changes in sensor shape before and after attachment to object (3). The top view is before attachment (3), and the bottom view is after attachment (3).

[0008] Figure 3 A schematic diagram of a cantilever beam structure made of semiconductor material:

[0009] Figure 4 A schematic diagram of a method for converting motion information into sound signals;

[0010] Figure 5A diagram illustrating how motion information is extracted from the signal output by the sensor;

[0011] Figure 6 A schematic diagram of a motion information spectrum analysis method;

[0012] Figure 7 A schematic diagram of a method for converting motion information into sound signals;

[0013] Figure 8 A schematic diagram of a method for directly acquiring motion information;

[0014] Figure 9 A schematic diagram of a device for detecting the motion of an object;

[0015] Figure 10 Schematic diagram of sensor and information processing circuit connection method;

[0016] Figure 11 A schematic diagram of the circuit configuration of a frequency converter;

[0017] Figure 12 A schematic diagram of a circuit that converts motion information into sound signals; Detailed Implementation

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: A device for detecting the motion of an object includes a sensor (4), or includes a frequency converter (5), or includes an audio amplifier (6), or includes a speaker (7) or headphones (8), or includes a precision detector (9), or includes one or more bandpass filters (10) with different bandwidths and center frequencies connected in parallel at their input terminals, or includes an oscilloscope (11) or digital voltmeter (12) connected to the output terminal of (10), or a voltage comparator (13) with a light-emitting diode display, or includes a carrier amplitude modulator (14) and an audio signal generator (15), and a speaker (16) or headphones (17) connected to the output terminal of (14), or includes an oscilloscope (18) connected to the output terminal of (9), or a digital voltmeter (19), or a voltage comparator (20) with a light-emitting diode display, such as Figure 9 . Figure 9 The sensor (4) described herein is connected directly or via an electrical signal amplifier (21), or via a wireless signal transmitting-receiving component (22), to a frequency converter (5) or a precision detector (9), or to an oscilloscope (23) or a digital voltmeter (24) or a voltage comparator (25) with a light-emitting diode display, as described above. Figure 10The frequency converter (5) consists of n precision active full-wave rectifiers (27) connected in series through resistor-capacitor couplers (26), where n takes the value 1, 2, 3, 4, 5, 6, 7 or 8, respectively multiplying the electrical signal output by the sensor (4) by 2, 4, 8, 16, 32, 64, 128 or 256 times. Figure 11 The bandpass filter (10) includes an active bandpass filter with a center frequency of 1.5 ± 1 Hz, or an active bandpass filter with a center frequency of 0.3 ± 0.2 Hz. The carrier amplitude modulator (14) includes an analog switch (28), the control terminal of which is connected to the audio signal generator (15), the input terminal of which is connected to the output terminal of (9), the output terminal of which is connected to the input terminal of the audio amplifier (29), and the output terminal of which is connected to the speaker (30) or the headphones (31), such as Figure 12 . Figure 9 The device shown includes a permanent magnet for detecting the motion of an object.

Claims

1. A method for detecting the motion of an object, comprising a piezoelectric film (2) attached to the surface of an elastic strip (1), wherein one end of (1) is fixed and the other end of (1) can vibrate freely, characterized in that... An object (3) is attached to one end of (1) that can vibrate freely. Under the influence of gravity on (3), (1) bends and the end of the thin sheet (1) attached to (3) is displaced perpendicular to the surface of (1). The displacement is greater than 0.05 compared to the distance between the two ends of (1). (2) together with (1) and (3) constitutes a sensor (4) for obtaining motion information of the object under this continuous deformation state of (1), as shown in Figure 1. The distance between the two ends of (1) is a. Under the influence of gravity on (3), the vertical displacement of the freely movable end of (1) is b. b / a>0.05, as shown in Figure 2.

2. The elastic strip sheet (1) of claim 1 has a width between 0.1 micrometers and 10 centimeters, a length between 0.2 micrometers and 20 centimeters, and a thickness between 0.1 micrometers and 0.5 millimeters; (1) is a sheet of polymer organic material, or a sheet of metal material, or a cantilever beam made of semiconductor material, as shown in Figure 3.

3. The electrical signal output by the sensor (4) of claim 1 enters the frequency converter (5) to change the frequency and then enters the audio amplifier (6). The speaker (7) or the earphone (8) is connected to (6) to emit sound information related to the motion state of the object that can be perceived by hearing, as shown in Figure 4. The electrical signal output by the sensor (4) may also enter the precision detector (9) composed of an operational amplifier, a semiconductor diode, a resistor and a capacitor to separate the motion information therein, as shown in Figure 5.

4. The electrical signal output from the precision detector (9) enters one or more bandpass filters (10) with different bandwidths and center frequencies connected in parallel at the input terminals. The (10) decomposes the motion information output from (9) into one or more specific bandwidth spectral information. The output terminal of (10) is connected to an oscilloscope (11), a digital voltmeter (12), or a voltage comparator (13) with a light-emitting diode display to display the signal characteristics of a specific frequency band, as shown in Figure 6. The electrical signal output from (9) may also enter a signal amplitude modulator (14). The (9) and the signal amplitude modulator (14) is connected to one input terminal, and the audio signal generator (15) is simultaneously connected to the other input terminal of (14). The output terminal of (14) obtains a signal whose motion information output by (9) modulates the specific frequency audio carrier. This signal emits sound related to the motion information through a speaker (16) or headphones (17), as shown in Figure 7. The electrical signal output by (9) either enters an oscilloscope (18), a digital voltmeter (19), or a voltage comparator (20) with a light-emitting diode display to directly display the acquired object motion information, as shown in Figure 8.

5. A device for detecting the motion of an object, characterized in that: This includes The sensor (4), or includes a frequency converter (5), or includes an audio amplifier (6), or includes a speaker (7) or headphones (8), or includes a precision detector (9), or includes one or more bandpass filters (10) with different bandwidths and center frequencies connected in parallel at the input, or includes an oscilloscope (11) or digital voltmeter (12) connected to the output of (10), or a voltage comparator (13) with a light-emitting diode display, or includes a carrier amplitude modulator (14) and an audio signal generator (15), and a speaker (16) or headphones (17) connected to the output of (14), or includes an oscilloscope (18) connected to the output of (9), or a digital voltmeter (19), or a voltage comparator (20) with a light-emitting diode display, as shown in FIG9.

6. The device for detecting the motion of an object as described in claim 5, comprising a sensor (4) connected directly or via an electrical signal amplifier (21), or via a wireless signal transmitting-receiving component (22), to a frequency converter (5) or a precision detector (9), or to an oscilloscope (23), a digital voltmeter (24), or a voltage comparator (25) with a light-emitting diode display, as shown in FIG10.

7. The frequency converter (5) included in the device for detecting the motion of an object according to claim 5 is composed of n precision active full-wave rectifiers (27) connected in series through resistor-capacitor couplers (26), where n takes the value 1, 2, 3, 4, 5, 6, 7 or 8, respectively performing frequency multiplication processing on the electrical signal output by the sensor (4) by 2, 4, 8, 16, 32, 64, 128 or 256 times, as shown in Figure 11.

8. The bandpass filter (10) in the device for detecting the motion of an object according to claim 5 includes an active bandpass filter with a center frequency of 1.5±1 Hz, or includes an active bandpass filter with a center frequency of 0.3±0.2 Hz.

9. The carrier amplitude modulator (14) in the device for detecting the motion of an object according to claim 5 includes an analog switch (28), the control terminal of (28) is connected to an audio signal generator (15), the input terminal of (28) is connected to the output terminal of (9), the output terminal of (28) is connected to the input terminal of an audio amplifier (29), and the output terminal of (29) is connected to a speaker (30) or an earphone (31), as shown in Figure 12.

10. The device for detecting the motion of an object as claimed in claim 5, comprising a permanent magnet.

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