Metal positioning device and method

Abstract

The invention discloses a metal positioning device and method, and belongs to the technical field of metal detection and positioning, and the device comprises a power module, a signal generation module, a signal conditioning module, a microcontroller module, a display module, a transmitting coil and a receiving coil. The power supply module is electrically connected with the signal generation module, the signal conditioning module, the microcontroller module and the display module and supplies power to the signal generation module and the transmitting coil and is used for generating an alternating current signal and applying the alternating current signal to the transmitting coil; the transmitting coil is used for generating and transmitting alternating electromagnetic waves; the number of the receiving coil is one, the receiving coil and the transmitting coil are distributed in the space, and magnetic field density lines of the receiving coil and the transmitting coil intersect, so that the receiving coil can receive electromagnetic waves transmitted by the transmitting coil and generate induced voltage. The design is simplified, the production cost is reduced, the testing and detecting process is simplified, and convenience and rapidness are achieved.

Description

Technical Field

[0001] The present application relates to the technical field of metal detection and positioning, and in particular to a metal positioning device and method. Background Art

[0002] In the prior art, metal object detectors are mostly used in military, security and engineering fields. In the military field, metal object detectors can be used to detect metal explosives buried underground; in the security field, they can be used to detect dangerous metal products carried on the person or hidden in item boxes; in the engineering field, they can be used to detect buried metal objects such as metal pipes.

[0003] The metal locating devices currently on the market are all based on the principle of electromagnetic field induction. First, an alternating electromagnetic field is generated by an alternating current through a transmitting coil, and then the receiving coil receives the electromagnetic wave and generates an induced voltage. Finally, the magnitude of the induced voltage is determined to locate the metal object. In the absence of target metal, the induced voltage on the receiving coil is close to zero. In the presence of a metal object, there is an induced voltage on the receiving coil. In existing technical solutions, multiple receiving coils may usually be required, and two steps are required to complete the positioning, which brings inconvenience to on-site positioning or detection personnel. Summary of the invention

[0004] One of the purposes of the present application is to solve the problems of the prior art and provide a metal positioning device and method.

[0005] To achieve the above objectives, the technical solution adopted in the present application is: a metal positioning device, comprising a power supply module, a signal generating module, a signal conditioning module, a microcontroller module, a display module, a transmitting coil and a receiving coil; the power supply module is electrically connected to the signal generating module, the signal conditioning module, the microcontroller module and the display module respectively and supplies power; the signal generating module is connected to the transmitting coil to generate an AC signal and apply it to the transmitting coil; the transmitting coil is used to generate and transmit alternating electromagnetic waves, and there is one transmitting coil; there is one receiving coil, and the receiving coil and the transmitting coil are distributed in space, and the magnetic field density lines of the two intersect, so that the receiving coil can receive the electromagnetic wave emitted by the transmitting coil and generate an induced voltage, and the receiving coil includes a receiving coil located in the same plane and wound in the same direction, and the receiving coil is wound and arranged in the same direction from the starting end to the end; the transmitting coil and the receiving coil are coupled to each other; the signal conditioning module is electrically connected to the receiving coil and the microcontroller module, so as to amplify the generated induced voltage and send it to the microcontroller module for sampling; the microcontroller module outputs the sampling result to the display module.

[0006] Preferably, a metal positioning method specifically includes the following steps: S1. When there is no metal in the detection space, the transmitting coil is driven to generate an alternating magnetic field, and the microcontroller samples and displays the current induced magnetic field strength value; S2. When there is metal in the detection space, the electromagnetic field distribution near the receiving coil will be changed, and the microcontroller samples the current induced magnetic field strength value; S3. When the difference between the current sampling value and the first sampling value exceeds a certain threshold, the display module displays the offset and alarms to prompt the presence of a metal object.

[0007] Preferably, the power module includes a power storage unit, a DC power adapter, a power filter and a power regulator; the power filter is used to reduce noise and interference in the power supply; the power regulator is used to stabilize the power supply and improve the performance of the device.

[0008] Preferably, the signal generating module comprises an oscillator unit and an amplifying unit, the oscillator unit emits an oscillation signal, and the amplifying unit amplifies the input signal.

[0009] Preferably, the signal conditioning module comprises a signal transmission unit and a signal processing unit, the signal transmission unit is used to receive and transmit data signals, and the signal processing unit is used to process the data signals.

[0010] Preferably, the transmitting coil forms a projection on the plane where the receiving coil is located.

[0011] Preferably, the starting end of the receiving coil has a plurality of nodes for selection of output.

[0012] Preferably, the end of the receiving coil has a plurality of nodes for optional output.

[0013] Preferably, the selection of the starting output node and the terminal output node of the receiving coil is controlled by a switch.

[0014] Compared with the prior art, the beneficial effects of this application are: (1) By ensuring that the transmitting coil and the receiving coil intersect in a vertical plane, so that the magnetic field density lines of the two coils intersect, the magnetic induction intensity of the metal object can be measured. The difference between the subsequent measured values ​​and the first test value is used as a reference, and the zero adjustment step is omitted. This application simplifies the design, reduces production costs, and simplifies the test detection process, making it convenient and quick. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a system block diagram of the metal positioning device of the present invention.

[0016] Figure 2 It is a flow chart of the metal positioning method of the present invention.

[0017] Figure 3 The present invention is a structural schematic diagram of a metal positioning device switch device connected to a receiving coil. DETAILED DESCRIPTION

[0018] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0019] In the description of the present application, it should be noted that directional words, such as the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of narrating the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and cannot be understood as limiting the specific scope of protection of the present application.

[0020] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0021] One of the preferred embodiments of the present application is as follows: Figure 1 to Figure 2 As shown, a metal positioning device includes a power supply module, a signal generating module, a signal conditioning module, a microcontroller module, a display module, a transmitting coil and a receiving coil; The power supply module is electrically connected to the signal generation module, the signal conditioning module, the microcontroller module, and the display module respectively to supply power; The signal generating module is connected to the transmitting coil and is used to generate an AC signal and apply it to the transmitting coil; The transmitting coil is used to generate and transmit alternating electromagnetic waves; there is one transmitting coil, which can generate an alternating electromagnetic field after receiving the AC signal input by the signal generating module; There is one receiving coil, and the receiving coil and the transmitting coil are distributed in space, and the magnetic field density lines of the two intersect, so that the receiving coil can receive the electromagnetic wave emitted by the transmitting coil and generate an induced voltage; the receiving coil includes a receiving coil located in the same plane and wound in the same direction, and the receiving coil is wound and arranged in the same direction from the starting end to the end. The transmitting coil and the receiving coil are coupled to each other to ensure that there is an overlapping and intersecting part between the receiving coil and the transmitting coil in the vertical space, so that the magnetic field density lines of the receiving coil and the transmitting coil can intersect. According to Faraday's law of electromagnetic induction, the measurement of magnetic field induction can be realized. Compared with the prior art, the present invention omits the zeroing link, which not only simplifies the design and reduces the production cost, but also simplifies the detection process, which is convenient and quick.

[0022] The signal conditioning module is electrically connected to the receiving coil and the microcontroller module; it is used to amplify, filter and shape the induced voltage generated by the receiving coil to facilitate sampling by the microcontroller; The microcontroller module outputs the sampling results to the display module.

[0023] A metal positioning method, the specific steps are as follows: Step 1: When there is no metal in the detection space, drive the transmitting coil to generate an alternating magnetic field, and sample and display the current induced magnetic field strength value through the microcontroller; Specifically, when there is no metal object, the positioning device is turned on, the signal generating module generates an AC signal to act on the transmitting coil, the transmitting coil generates an alternating magnetic field, the receiving coil generates an induced voltage and sends it to the signal conditioning module for processing, and the microcontroller samples and displays it through the display module; Step 2: When there is metal in the detection space, the electromagnetic field distribution near the receiving coil will change, and the current induced magnetic field strength value will be sampled by the microcontroller; specifically, when a metal object approaches the positioning device of the present invention, the electromagnetic field distribution of the original space will be destroyed, and the signal sampled by the microcontroller will be different from the original signal; Step 3: When the difference between the current sampling value and the first sampling value exceeds a certain threshold, the display module displays the offset and issues an alarm to indicate the presence of a metal object; specifically, when the difference between the two signals exceeds a certain threshold, the difference is displayed to indicate the presence of a metal object in the space.

[0024] The power module includes a power storage unit, a DC power adapter, a power filter, and a power regulator. An unstable power supply will reduce the sensitivity of the metal detector, reduce the detector's ability to respond to small or low-density metal targets, and make the detector unable to accurately identify smaller metal objects. In addition, unstable power supply will cause other electronic components of the metal detector to malfunction. Components such as circuit boards, sensors, and control systems may be damaged due to power problems, affecting the overall performance of the device. This reduces the reliability and accuracy of detection. The power regulator is used to stabilize the power supply and improve the performance of the device. The power filter can help reduce noise and interference in the power supply and improve the stability of the metal detector. The power module uses a DC power supply with an input voltage of 12V, 24V or 36V, an output voltage of 5V and 12V, etc. The output current varies depending on the usage. For example, the current required by the control circuit is generally smaller than the current required by the sensing circuit.

[0025] The signal generation module includes an oscillator unit and an amplifier unit. The oscillator unit sends out an oscillation signal. The oscillator unit adopts an LC tuning circuit (inductor, capacitor) to adjust the resonant frequency of the oscillator by selecting appropriate inductor and capacitor values. The internal feedback network sends part of the output signal back to the input end to form positive feedback, so that the system generates self-excited oscillation, thereby stably outputting high-frequency signals; the amplifier unit amplifies the input signal to maintain the oscillation process and ensure that the output signal has sufficient amplitude and stability.

[0026] The signal conditioning module includes a signal transmission unit and a signal processing unit. The signal transmission unit is used to receive and transmit data signals, and the signal processing unit is used to process data signals. The processed signal is transmitted to the microcontroller module, and the microcontroller module outputs the sampling result to the display module. Specifically, the microcontroller module and the small signal processing unit both include a processor, and the processor model is CMS8S6990SSOP24.

[0027] The transmitting coil forms a projection on the plane where the receiving coil is located, the receiving coil includes all the projections, the receiving coil includes part of the projections, the receiving coils are symmetrically distributed around the projections, and the receiving coils are asymmetrically distributed around the projections.

[0028] The starting end of the receiving coil has multiple nodes for optional output, and the end of the receiving coil has multiple nodes for optional output. The selection of the output node at the starting end of the receiving coil can be controlled by a switch, and the selection of the output node at the end of the receiving coil can be controlled by a switch. The switch can be an integrated analog switch / multiplexer, a discrete component field effect transistor or triode, or a manually controlled dip switch.

[0029] In this embodiment, if Figure 3As shown, in the absence of a metal object to be tested, the transmitting coil is driven to generate an alternating magnetic field. The optimal configuration combination and initial value of the switch are determined according to the following steps: U1 starts to conduct from channel 0, U2 conducts channel ch0, the output terminals com0 and com1 between U1 and U2 are conditioned and sampled by the conditioning circuit, and the sampled value Value0 is recorded.

[0030] Change the channel number of U2 in sequence, repeat the previous step, and record the sampled values ​​Value1, Value2, ..., value7.

[0031] Determine the smallest number among Value0, Value1, ..., Value7 as V0 and its position (corresponding to the channel number of U2) Change the channel number of U1 in sequence and repeat the above two steps until all 8 channels of U1 are passed through, then 8 data V0, V1...V7 and their respective positions (corresponding to the channel number of U2) will be obtained.

[0032] The smallest number among V0, V1...V7 is used as the initial value, and its position in the 8 data is determined at the same time, and this position corresponds to the channel number of U1. So far, the optimal combination of the switch device corresponding to the receiving coil and its corresponding initial voltage value can be determined. The optimal channel combination and initial voltage value can be stored in the EEPROM of the MPU so that they can be directly called when the device is turned on next time, shortening the time for the device to start self-test.

[0033] The channel configuration to determine the best combination of U1 and U2 and the initial value of the coil can also be set as a self-test function, which is implemented by the program execution key function.

[0034] The selection of U1 and U2 channels is controlled by the microprocessor through address lines A2, A1, and A0.

[0035] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A metal positioning device, characterized in that: include: Power module, signal generation module, signal conditioning module, microcontroller module, display module, transmitting coil and receiving coil; The power supply module is electrically connected to the signal generating module, the signal conditioning module, the microcontroller module, and the display module respectively to supply power; The signal generating module is connected to the transmitting coil and is used to generate an AC signal and apply it to the transmitting coil; The transmitting coil is used to generate and transmit alternating electromagnetic waves, and there is one transmitting coil; There is one receiving coil, and the receiving coil and the transmitting coil are distributed in space, and the magnetic field density lines of the two intersect, so that the receiving coil can receive the electromagnetic wave emitted by the transmitting coil and generate an induced voltage; the receiving coil includes a receiving coil located in the same plane and wound in the same direction, and the receiving coil is wound in the same direction from the starting end to the end; The transmitting coil and the receiving coil are coupled to each other; The signal conditioning module is electrically connected to the receiving coil and the microcontroller module so as to amplify the generated induced voltage and send it to the microcontroller module for sampling; The microcontroller module outputs the sampling result to the display module.

2. A metal positioning method according to claim 1, characterized in that: The following steps are involved: S1. When there is no metal in the detection space, the transmitting coil is driven to generate an alternating magnetic field, and the microcontroller samples and displays the current induced magnetic field strength value; S2. When there is metal in the detection space, the electromagnetic field distribution near the receiving coil will change, and the current induced magnetic field strength value will be sampled by the microcontroller; S3. When the difference between the current sampling value and the first sampling value exceeds a certain threshold, the display module displays the offset and issues an alarm to indicate the presence of a metal object.

3. A metal positioning device as claimed in claim 1, characterized in that: The power module includes a power storage unit, a DC power adapter, a power filter and a power regulator; The power supply filter is used to reduce noise and interference in the power supply; The power regulator is used to stabilize the power supply and improve the performance of the device.

4. A metal positioning device as claimed in claim 1, characterized in that: The signal generating module comprises an oscillator unit and an amplifying unit. The oscillator unit sends out an oscillation signal, and the amplifying unit amplifies an input signal.

5. A metal positioning device as claimed in claim 1, characterized in that: The signal conditioning module includes a signal transmission unit and a signal processing unit. The signal transmission unit is used to receive and transmit data signals, and the signal processing unit is used to process the data signals.

6. A metal positioning device as claimed in claim 1, characterized in that: The transmitting coil forms a projection on the plane where the receiving coil is located.

7. A metal positioning device as claimed in claim 1, characterized in that: The starting end of the receiving coil has a plurality of nodes for selection of output.

8. A metal positioning device as claimed in claim 1, characterized in that: The end of the receiving coil has a plurality of nodes for optional output.

9. A metal positioning device as claimed in claim 1, characterized in that: The selection of the starting output node and the terminal output node of the receiving coil is controlled by a switch.

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