Novel internal structure force sensor

Abstract

The utility model discloses a novel internal structure force sensor, and belongs to the technical field of force sensors. Comprising a packaging shell, a three-layer sensing layer structure, a signal processing circuit and a wireless transmission module. Each sensing layer structure is composed of a rigid supporting layer, a first flexible sensing layer, a second flexible sensing layer, a third flexible sensing layer, a temperature compensation layer and a piezoelectric sensing layer which are used for measuring force in the X direction, force in the Y direction and force in the Z direction and high-frequency dynamic force. And the signal processing circuit comprises a strain gauge signal acquisition module, a piezoelectric material signal acquisition module, a temperature compensation module and a signal output module, and is used for acquiring, processing and outputting signals. And the wireless transmission module wirelessly transmits the processed signal to external equipment. According to the multi-dimensional force sensor, the multi-layer composite structure is compact in design and easy to integrate into various devices, the temperature compensation design effectively eliminates the influence of temperature change on the measurement result, the stability and the reliability of the sensor are improved, and high-precision and high-sensitivity multi-dimensional force measurement is realized.

Description

Technical Field

[0001] This utility model relates to the field of force sensor technology, and in particular to a novel internal structure force sensor. Background Technology

[0002] Force sensors are widely used in robotics, medical equipment, industrial automation, and other fields to measure static and dynamic forces. Existing force sensors have limitations in sensitivity, accuracy, and temperature compensation, especially in multidimensional force measurement and high-frequency dynamic force measurement. This invention solves these problems through an innovative multi-layer composite structure design, combining a flexible sensing layer, a rigid support layer, a piezoelectric sensing layer, and a temperature compensation layer. It provides a novel internal structure force sensor with high precision, high sensitivity, and temperature compensation functionality. Utility Model Content

[0003] The purpose of this invention is to provide a novel internal structural force sensor that solves the technical problems of existing force sensors in terms of temperature drift, multidimensional force measurement, high-frequency dynamic force measurement, signal transmission, and structural complexity.

[0004] To achieve the above objectives, this utility model provides a novel internal structural force sensor, including a packaged shell. Inside the packaged shell, three sensing layers are arranged in sequence. The three sensing layers are electrically connected to a signal processing circuit and a wireless transmission module arranged in sequence at the bottom. The bottom of the wireless transmission module is closely attached to the packaged base plate. The two sides of the packaged base plate are fixedly connected to the packaged shell by packaged nails.

[0005] Preferably, the first sensing layer structure is a combination of a rigid support layer, a flexible sensing layer, a temperature compensation layer, and a piezoelectric sensing layer;

[0006] The second sensing layer structure is a combination of a rigid support layer, a flexible sensing layer, a temperature compensation layer, and a piezoelectric sensing layer.

[0007] The second sensing layer structure is a combination of a rigid support layer, a flexible sensing layer, a temperature compensation layer, and a piezoelectric sensing layer.

[0008] Preferably, the internal structure of the rigid support layer is a mesh structure or a honeycomb structure.

[0009] Preferably, the first flexible sensing layer, the second flexible sensing layer, and the third flexible sensing layer are made of polyimide film, and strain gauges in the X, Y, and Z directions are printed on the first flexible sensing layer, the second flexible sensing layer, and the third flexible sensing layer, respectively.

[0010] Preferably, the temperature compensation layer is made of copper or a gold-bonded material.

[0011] Preferably, the piezoelectric sensing layer is made of lead zirconate titanate (PZT) material.

[0012] Preferably, the signal processing circuit includes a strain gauge signal acquisition module, a piezoelectric material signal acquisition module, a temperature compensation module, and a signal output module;

[0013] The strain gauge signal acquisition module is used to acquire the signals of the strain gauges in the flexible sensing layer;

[0014] The piezoelectric material signal acquisition module is used to acquire signals from the piezoelectric material in the piezoelectric sensing layer;

[0015] The temperature compensation module is used to compensate for the impact of temperature changes on the measurement results;

[0016] The signal output module is used to output the processed signal to an external device.

[0017] Therefore, the novel internal structural force sensor of this invention, employing the above-described structure, has the following beneficial effects:

[0018] (1) This utility model is easy to integrate into various devices through multi-layer composite structure design. Combining flexible sensing layer and rigid support layer, it significantly improves the measurement accuracy of sensor and can accurately measure force in the X, Y and Z directions. The introduction of piezoelectric sensing layer enables sensor to sense high-frequency dynamic force and expands the application range of sensor.

[0019] (2) The temperature compensation layer and temperature compensation module of this utility model effectively eliminate the influence of temperature changes on the measurement results, improve the stability and reliability of the sensor, and perform well, especially in environments with large temperature changes.

[0020] (3) The flexible sensing layer of this utility model measures the force in the X, Y and Z directions respectively, and the piezoelectric sensing layer measures the high-frequency dynamic force, realizing the synchronous measurement of multi-dimensional forces and meeting the needs of complex application scenarios.

[0021] (4) The wireless transmission module of this utility model realizes real-time wireless transmission of signals, which facilitates remote monitoring and data acquisition, reduces wiring complexity, and improves the flexibility and applicability of the sensor.

[0022] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of a novel internal force sensor according to the present invention;

[0024] Figure Labels

[0025] 1. Encapsulation shell, 2. Rigid support layer, 3. Flexible sensing layer one, 3a. Flexible sensing layer two, 3b. Flexible sensing layer three, 4. Temperature compensation layer, 5. Piezoelectric sensing layer, 6. Signal processing circuit, 7. Wireless transmission module, 8. Encapsulation pin, 9. Encapsulation base. Detailed Implementation

[0026] The technical solution of this utility model will be further described below with reference to the accompanying drawings and embodiments.

[0027] Unless otherwise defined, the technical or scientific terms used in this utility model shall have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "first," "second," and similar terms used in this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0028] Example

[0029] like Figure 1 As shown, this utility model provides a novel internal structural force sensor, as detailed below:

[0030] The encapsulation shell 1 has three layers of sensing layer structure arranged in sequence inside. The three layers of sensing layer structure are electrically connected to the signal processing circuit 6 and the wireless transmission module 7 arranged in sequence at the bottom. The bottom of the wireless transmission module 7 is closely attached to the encapsulation base plate 9. The two sides of the encapsulation base plate 9 are fixedly connected to the encapsulation shell 1 by encapsulation nails 8.

[0031] The first sensing layer structure is a combination of a rigid support layer 2, a flexible sensing layer 3, a temperature compensation layer 4, and a piezoelectric sensing layer 5.

[0032] The second sensing layer structure is a combination of a rigid support layer 2, a flexible sensing layer 3a, a temperature compensation layer 4, and a piezoelectric sensing layer 5.

[0033] The third sensing layer structure is a combination of a rigid support layer 2, a flexible sensing layer 3b, a temperature compensation layer 4, and a piezoelectric sensing layer 5. Each of the above layers is bonded together with an adhesive (such as epoxy resin).

[0034] The internal structure of the rigid support layer 2 is a mesh structure or a honeycomb structure.

[0035] Flexible sensing layer 1 (3), flexible sensing layer 2 (3a), and flexible sensing layer 3 (3b) are all made of polyimide film, and strain gauges in the X, Y, and Z directions are printed on flexible sensing layer 1 (3), flexible sensing layer 2 (3a), and flexible sensing layer 3 (3b), respectively.

[0036] Temperature compensation layer 4 is made of copper or nickel alloy.

[0037] The piezoelectric sensing layer 5 is made of lead zirconate titanate (PZT) material.

[0038] The signal processing circuit 6 includes a strain gauge signal acquisition module, a piezoelectric material signal acquisition module, a temperature compensation module, and a signal output module.

[0039] The strain gauge signal acquisition module is used to acquire signals from the strain gauges in the flexible sensing layer.

[0040] The piezoelectric material signal acquisition module is used to acquire signals from the piezoelectric material in the piezoelectric sensing layer.

[0041] The temperature compensation module is used to compensate for the impact of temperature changes on the measurement results.

[0042] The signal output module is used to output the processed signal to an external device.

[0043] The wireless transmission module 7 is used to wirelessly transmit the processed signal to an external device.

[0044] The encapsulation pin 8 is used to fix the encapsulation base plate 9 to the encapsulation shell 1.

[0045] The packaging base plate 9 is located at the bottom of the sensor and is used to support the wireless transmission module 7 and the signal processing circuit 6.

[0046] Since the signal processing circuits described above all use existing devices, and signal processing circuits are common knowledge in the field, and can be arranged in various ways to form circuit diagrams, they will not be shown here.

[0047] The following demonstrates the operating steps of the strain gauge signal acquisition module, piezoelectric material signal acquisition module, temperature compensation module, and signal output module:

[0048] Strain gauge signal acquisition module:

[0049] Strain gauge R1 / R2 → Wheatstone bridge → Instrumentation amplifier → Low-pass filter → Σ-Δ ADC → MCU / DSP; the existing Wheatstone bridge consists of four resistors, with R1 / R2 serving as two strain gauges and R3 / R4 as fixed resistors. The instrumentation amplifier can be an ADI AD620 or a TI INA128; the low-pass filter is a first-order RC filter; the Σ-Δ ADC can be an ADI AD7124 or a TI ADS1248.

[0050] Specifically, strain gauge R1 → Wheatstone bridge (V+) → instrumentation amplifier (IN+).

[0051] Strain gauge R2 → Wheatstone bridge (V-) → Instrumentation amplifier (IN-);

[0052] Fixed resistor R3 → Wheatstone bridge (V+);

[0053] Fixed resistor R4 → Wheatstone bridge (V-);

[0054] Instrumentation amplifier (OUT) → Low-pass filter (IN);

[0055] Low-pass filter (OUT) → Σ-Δ type ADC (AIN+).

[0056] Piezoelectric material signal acquisition module:

[0057] Piezoelectric material → charge amplifier → operational amplifier → bandpass filter → SAR ADC → MCU / DSP; the charge amplifier uses the existing ADI AD549 or TI OPA129; the operational amplifier uses the existing ADI OP07 or TI OPA227; the bandpass filter is a second-order RC filter; the SAR ADC uses ADI AD7685 or TI ADS8860.

[0058] Specifically, piezoelectric materials → charge amplifier (IN-);

[0059] Charge amplifier (OUT) → Operational amplifier (IN+);

[0060] Operational amplifier (OUT) → bandpass filter (IN);

[0061] Bandpass filter (OUT) → SAR ADC (AIN+).

[0062] Temperature compensation module:

[0063] Temperature sensor → I2C / SPI interface → MCU / DSP; the temperature sensor uses Maxim's DS18B20 or TI's TMP117 from existing technologies; the microcontroller (MCU) or DSP uses ST's STM32 series or TI's TMS320 series.

[0064] Specifically, temperature sensor (DQ) → MCU / DSP (GPIO)

[0065] MCU / DSP (I2C / SPI) → Temperature sensor (SCL / SDA).

[0066] Signal output module:

[0067] MCU / DSP → SPI / I2C interface → Wireless transmission module;

[0068] MCU / DSP → Operational Amplifier → Analog Output;

[0069] The wireless transmission module uses Nordic's nRF52840 or TI's CC2640; the operational amplifier for analog signal output uses ADI's OP07.

[0070] Specifically, MCU / DSP (SPI / I2C) → Wireless transmission module (MOSI / MISO / SCK)

[0071] MCU / DSP (DAC_OUT) → Operational Amplifier (IN+)

[0072] Operational amplifier (OUT) → Analog output.

[0073] The antenna portion of the wireless transmission module can be embedded in an external encapsulation layer.

[0074] Therefore, this utility model adopts a novel internal structure force sensor, which is compact through a multi-layer composite structure design, is easy to integrate into various devices, and the temperature compensation design effectively eliminates the influence of temperature changes on the measurement results, improves the stability and reliability of the sensor, and realizes high-precision and high-sensitivity multidimensional force measurement.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solution of this utility model, and these modifications or equivalent substitutions cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of this utility model.

Claims

1. A novel internal structure force sensor characterized by, The package shell is internally sequentially arranged with three layers of sensing layer structures, the three layers of sensing layer structures are respectively electrically connected with a signal processing circuit and a wireless transmission module sequentially arranged at the bottom, the wireless transmission module is tightly attached to the packaging bottom plate, and the packaging bottom plate is fixedly connected with the packaging shell through packaging nails on both sides.

2. A novel internal structural force sensor according to claim 1, characterized in that: The first layer of sensing layer structure is a combination of a rigid support layer, a flexible sensing layer one, a temperature compensation layer and a piezoelectric sensing layer. The second layer of sensing layer structure is a combination of a rigid support layer, a flexible sensing layer two, a temperature compensation layer and a piezoelectric sensing layer. The second layer of sensing layer structure is a combination of a rigid support layer, a flexible sensing layer three, a temperature compensation layer and a piezoelectric sensing layer.

3. A novel internal structure force sensor according to claim 2, characterized in that: The internal structure of the rigid support layer is a net-like structure or a honeycomb-like structure.

4. A novel internal structural force sensor according to claim 2, characterized in that: The flexible sensing layer one, the flexible sensing layer two and the flexible sensing layer three adopt polyimide film, and the flexible sensing layer one, the flexible sensing layer two and the flexible sensing layer are respectively printed with strain gauges in X, Y and Z directions.

5. A novel internal structural force sensor according to claim 2, characterized in that: The temperature compensation layer adopts copper or gold material.

6. A novel internal structural force sensor according to claim 2, characterized by: The piezoelectric sensing layer adopts lead zirconate titanate (PZT) material.

7. A novel internal structural force sensor according to claim 2, characterized by: The signal processing circuit includes a strain gauge signal acquisition module, a piezoelectric material signal acquisition module, a temperature compensation module and a signal output module. The strain gauge signal acquisition module is used to acquire the signal of the strain gauge in the flexible sensing layer. The piezoelectric material signal acquisition module is used to acquire the signal of the piezoelectric material in the piezoelectric sensing layer. The temperature compensation module is used to compensate the influence of temperature change on the measurement results. The signal output module is used to output the processed signal to an external device.

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