Eddy current type force sensor

Abstract

The invention provides an eddy current type force sensor. The eddy current type force sensor comprises a signal acquisition circuit board and a metal structural member, the signal acquisition circuit board is detachably connected with the metal structural member, and a plurality of eddy current induction areas are formed between the signal acquisition circuit board and the metal structural member; the metal structural member is used for generating deformation under the action of force and driving the signal acquisition circuit board to generate displacement; the signal acquisition circuit board is used for generating and outputting sine wave signals corresponding to the eddy current induction areas when displacement is generated, and the frequency of the sine wave signals is used for representing the size of the six-dimensional component of the force, so that the acquisition precision of the eddy current type force sensor is improved, and the cost of the eddy current type force sensor is reduced.

Description

Technical Field

[0001] This application relates to the field of force sensor technology, and more specifically, to an eddy current force sensor. Background Technology

[0002] With the increasing integration of robots with their environment, six-dimensional force sensors provide multi-dimensional force and torque feedback, enabling robots to interact with the environment and humans more intelligently and safely, significantly improving the reliability, adaptability, and safety of robots in complex tasks.

[0003] Currently, six-dimensional force sensors are mainly strain gauge type six-dimensional force sensors, which require the additional use of strain gauges to meet force measurement requirements, increasing costs. Furthermore, the resistance value of strain gauges will creep and drift under static conditions, requiring repeated calibration to maintain accuracy, resulting in high maintenance costs. The resistance value of strain gauges is also easily affected by ambient temperature, leading to lower accuracy in complex environmental conditions, requiring complex compensation circuits to eliminate temperature drift.

[0004] Therefore, the design of six-dimensional force sensors in the existing technology has certain limitations. Summary of the Invention

[0005] The purpose of this application is to address the shortcomings of the prior art by providing an eddy current force sensor to solve the practical problem of the limitations in the design of existing six-dimensional force sensors.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: In a first aspect, embodiments of this application provide an eddy current force sensor, which includes: a signal acquisition circuit board and a metal structural component; The signal acquisition circuit board is detachably connected to the metal structure, and multiple eddy current induction areas are formed between the signal acquisition circuit board and the metal structure. The metal structural component is used to deform under the action of force and drive the signal acquisition circuit board to generate displacement. The signal acquisition circuit board is used to generate and output sinusoidal signals corresponding to each eddy current induction region when displacement is generated. The frequency of the sinusoidal signal is used to characterize the magnitude of the six-dimensional components of the force.

[0007] As an optional implementation, the signal acquisition circuit board includes: a first signal acquisition circuit board and a second signal acquisition circuit board; Multiple first eddy current induction regions are formed between the first signal acquisition circuit board and the metal structural component; Multiple second eddy current induction regions are formed between the second signal acquisition circuit board and the metal structural component; The first signal acquisition circuit board is used to generate and output a first sine wave signal corresponding to each first eddy current induction region when displacement is generated. The frequency of the first sine wave signal is used to characterize the three translational components of the force. The second signal acquisition circuit board is used to generate and output a second sine wave signal corresponding to each second eddy current induction region when displacement is generated. The frequency of the second sine wave signal is used to characterize the three rotational components of the force.

[0008] As an optional implementation, the first signal acquisition circuit board includes: a first signal acquisition circuit and a first planar coil; When the AC signal passes through the first planar coil, the first signal acquisition circuit board acts as the first electrode plate, and the metal structural component acts as the second electrode plate. The first signal acquisition circuit board and the metal structural component form multiple first equivalent inductances. The first signal acquisition circuit is used to acquire the inductance change of each first equivalent inductor when the first signal acquisition circuit board is displaced, and to generate and output the first sine wave signal corresponding to each first equivalent inductor based on the inductance change of each first equivalent inductor.

[0009] As an optional implementation, the second signal acquisition circuit board includes: a second signal acquisition circuit and a second planar coil; When the AC signal passes through the second planar coil, the second signal acquisition circuit board acts as the third electrode plate, and the metal structural component acts as the fourth electrode plate. The second signal acquisition circuit board and the metal structural component form multiple second equivalent inductances. The second signal acquisition circuit is used to acquire the inductance change of each second equivalent inductor when the second signal acquisition circuit board is displaced, and to generate and output the second sine wave signal corresponding to each second equivalent inductor based on the inductance change of each second equivalent inductor.

[0010] As an optional implementation, the first signal acquisition circuit includes: a first amplification module and a first frequency selection module; The power supply terminal of the first amplification module is connected to the power supply voltage, the input terminal of the first amplification module is connected to the first output terminal of the first frequency selection module, the first output terminal of the first amplification module is connected to the input terminal of the first frequency selection module, and the second output terminal of the first amplification module is grounded. The second output terminal of the first frequency selection module is grounded.

[0011] As an optional implementation, the first signal acquisition circuit further includes: a first coupling module and a second coupling module; The input terminal of the first coupling module is connected to the first output terminal of the first frequency selection module, and the output terminal of the first coupling module is connected to the input terminal of the first amplification module. The input terminal of the second coupling module is connected to the first output terminal of the first amplification module, and the output terminal of the second coupling module is connected to the input terminal of the first frequency selection module.

[0012] As an optional implementation, the first amplification module includes: a first transistor, a first resistor, a second resistor, a third resistor, a fourth resistor, and a first capacitor; The base of the first transistor is connected to the output terminal of the first coupling module, the first terminal of the first resistor, and the first terminal of the second resistor. The collector of the first transistor is connected to the first terminal of the fourth resistor and the input terminal of the second coupling module. The emitter of the first transistor is connected to one end of the third resistor and one end of the first capacitor. The second terminal of the first resistor and the second terminal of the fourth resistor are connected to the power supply voltage; The second terminal of the second resistor, the second terminal of the third resistor, and the second terminal of the first capacitor are grounded.

[0013] As an optional implementation, the first frequency selection module includes: a second capacitor, a third capacitor, and a first inductor, wherein the first inductor is one of a plurality of first equivalent inductors formed by the first signal acquisition circuit board and the metal structure. The first terminal of the second capacitor and the first terminal of the first inductor are both connected to the output terminal of the second coupling module; The second terminal of the second capacitor and the first terminal of the third capacitor are grounded. The second terminal of the third capacitor and the second terminal of the first inductor are both connected to the input terminal of the first coupling module.

[0014] As an optional implementation, the first coupling module includes: a fourth capacitor; The first terminal of the fourth capacitor is connected to the first output terminal of the first frequency selection module; The second terminal of the fourth capacitor is connected to the input terminal of the first amplification module.

[0015] As an optional implementation, the second coupling module includes: a fifth capacitor; The first terminal of the fifth capacitor is connected to the first output terminal of the first amplification module; The second terminal of the fifth capacitor is connected to the input terminal of the first frequency selection module.

[0016] The beneficial effects of this application are: This application provides an eddy current force sensor, which includes a signal acquisition circuit board and a metal structural component. The signal acquisition circuit board and the metal structural component are detachably connected, and multiple eddy current sensing regions are formed between the signal acquisition circuit board and the metal structural component. Under the action of force, the metal structural component deforms, causing the signal acquisition circuit board to displace. During this displacement, the distance and overlapping area between the signal acquisition circuit board and the metal structural component change. Based on the eddy current effect, a sinusoidal signal corresponding to each eddy current sensing region is generated and output. The frequency of the sinusoidal signal corresponding to each eddy current sensing region represents the magnitude of the six-dimensional force component. By accurately calculating the six-dimensional force component through the frequency of the sinusoidal signal and the linear matrix relationship of the six-dimensional force component, the acquisition accuracy of the eddy current six-dimensional force sensor is improved, and the cost of the eddy current six-dimensional force sensor is reduced. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 1 ; Figure 2 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 2 ; Figure 3 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 3 ; Figure 4 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 4 ; Figure 5 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 5 .

[0019] Reference numerals: Signal acquisition circuit board: 10; Metal structural component: 20; First signal acquisition circuit board: 11; Second signal acquisition circuit board: 12; First planar coil: Z-COIL; Second planar coil: T-COIL; First amplification module: 13; First frequency selection module: 14; First coupling module: 15; Second coupling module: 16; First transistor: Q1; First resistor: R1; Second resistor: R2; Third resistor: R3; Fourth resistor: R4; First capacitor: C1; Second capacitor: C2; Third capacitor: C3; First inductor: L1; Fourth capacitor: C4; Fifth capacitor: C5. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the accompanying drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.

[0021] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0022] It should be noted that the term "comprising" will be used in the embodiments of this application to indicate the presence of the features declared thereafter, but does not exclude the addition of other features.

[0023] In the field of force sensors, six-dimensional force sensors enable robots to interact with the environment and humans more intelligently and safely by providing multi-dimensional force and torque feedback. Currently, six-dimensional force sensors are mainly strain gauge type, requiring the additional use of strain gauges to meet force measurement needs, increasing costs. Furthermore, the resistance of strain gauges tends to creep and drift under static conditions, requiring repeated calibration to maintain accuracy, resulting in high maintenance costs. The resistance of strain gauges is also susceptible to ambient temperature, leading to lower accuracy in complex environments and necessitating complex compensation circuits to eliminate temperature drift. In other words, the design of existing six-dimensional force sensors has certain limitations.

[0024] Based on the above-mentioned problems, this application provides an eddy current force sensor that utilizes the eddy current effect between the signal acquisition circuit board and the metal structural component to measure the force on the metal structural component, thereby improving the acquisition accuracy of the eddy current force sensor and reducing its cost.

[0025] Figure 1 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 1 ,like Figure 1 As shown, the eddy current force sensor includes: a signal acquisition circuit board 10 and a metal structural component 20.

[0026] The signal acquisition circuit board 10 is detachably connected to the metal structure 20, and multiple eddy current induction areas are formed between the signal acquisition circuit board and the metal structure 20.

[0027] Optionally, refer to Figure 1 In the eddy current force sensor, the metal structure 20 is the component that directly bears the external force. The signal acquisition circuit board 10 is detachably connected to the metal structure 20. When the metal structure 20 is subjected to force, it transmits the force to the connected signal acquisition circuit board 10.

[0028] When the signal acquisition circuit board 10 and the metal structure 20 are assembled together with screws, multiple eddy current induction regions are formed between the signal acquisition circuit board 10 and the metal structure 20, that is, the eddy current effect is formed.

[0029] The metal structural component 20 is used to deform under the action of force and drive the signal acquisition circuit board 10 to move.

[0030] Optionally, the metal structural component 20 deforms under the action of external force, and drives the signal acquisition circuit board 10 connected to the metal structural component 20 to move, so that the distance and overlapping area between the metal structural component 20 and the signal acquisition circuit board 10 change, thereby changing the eddy current induction state between the metal structural component 20 and the signal acquisition circuit board 10.

[0031] The signal acquisition circuit board 10 is used to generate and output sinusoidal signals corresponding to each eddy current induction region when displacement is generated. The frequency of the sinusoidal signal is used to characterize the magnitude of the six-dimensional components of the force.

[0032] Optionally, when the signal acquisition circuit board 10 generates displacement, the distance and overlapping area between the signal acquisition circuit board 10 and the metal structure 20 in each eddy current sensing region change. Based on the eddy current effect, a sinusoidal signal corresponding to each eddy current sensing region is generated and output. The sinusoidal signal corresponding to each eddy current sensing region is used to characterize the magnitude of the six-dimensional component of the force.

[0033] Specifically, as the distance and overlapping area between the signal acquisition circuit board 10 and the metal structure 20 change, the frequency of the sinusoidal signal corresponding to each eddy current induction area changes. The frequency of the sinusoidal signal has a linear matrix relationship with the six-dimensional components of the force. Based on the frequency of the sinusoidal signal, the force on the metal structure 20 can be accurately measured.

[0034] In this embodiment, the eddy current force sensor includes a signal acquisition circuit board and a metal structural component. The signal acquisition circuit board and the metal structural component are detachably connected, and multiple eddy current sensing regions are formed between them. Under the action of force, the metal structural component deforms, causing the signal acquisition circuit board to displace. During this displacement, the distance and overlapping area between the signal acquisition circuit board and the metal structural component change. Based on the eddy current effect, a sinusoidal signal corresponding to each eddy current sensing region is generated and output. The frequency of the sinusoidal signal corresponding to each eddy current sensing region characterizes the magnitude of the six-dimensional force component. By accurately calculating the six-dimensional force component using the frequency of the sinusoidal signal and the linear matrix relationship of the six-dimensional force component, the acquisition accuracy of the eddy current six-dimensional force sensor is improved, and the cost of the eddy current six-dimensional force sensor is reduced.

[0035] Figure 2 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 2 ,like Figure 2 As shown, the signal acquisition circuit board 10 includes a first signal acquisition circuit board 11 and a second signal acquisition circuit board 12.

[0036] Multiple first eddy current sensing regions are formed between the first signal acquisition circuit board 11 and the metal structure 20; multiple second eddy current sensing regions are formed between the second signal acquisition circuit board 12 and the metal structure 20.

[0037] Optionally, refer to Figure 2After the signal acquisition circuit board 10 and the metal structure 20 are assembled together, multiple first eddy current induction regions are formed between the first signal acquisition circuit board 11 and the metal structure 20, and multiple second eddy current induction regions are formed between the second signal acquisition circuit board 12 and the metal structure 20.

[0038] The first signal acquisition circuit board 11 is used to generate and output the first sine wave signal corresponding to each first eddy current induction region when displacement is generated. The frequency of the first sine wave signal is used to characterize the three translational components of the force.

[0039] Optionally, when external forces (including forces along the X-axis) Force along the Y-axis Force along the Z-axis The three translational components and the torque about the X-axis Torque around the Y-axis Torque around the Z-axis When the three rotational components of the electric eddy current (EV) act on the six-dimensional force sensor, the metal structural component 20 undergoes corresponding deformation according to the type of force.

[0040] Among them, the metal structural component 20 is subjected to translational force (including force along the X-axis). Force along the Y-axis Force along the Z-axis Translational deformation occurs, and rotational torque (including torque about the X-axis) is applied. Torque around the Y-axis Torque around the Z-axis This can cause torsional or bending deformation.

[0041] The first signal acquisition circuit board 11 undergoes linear displacement in the X / Y / Z directions due to the translational deformation of the metal structure 20. The distance and overlapping area between the first signal acquisition circuit board 11 and the metal structure 20 change in each first eddy current induction region. Based on the eddy current effect, a first sine wave signal corresponding to each first eddy current induction region is generated and output. This first sine wave signal is used to characterize the force along the X-axis. Force along the Y-axis Force along the Z-axis The three translation components.

[0042] The second signal acquisition circuit board 12 is used to generate and output the second sine wave signal corresponding to each second eddy current induction region when displacement is generated. The frequency of the second sine wave signal is used to characterize the three rotational components of the force.

[0043] Optionally, the second signal acquisition circuit board 12 undergoes angular displacement in the X / Y / Z directions due to the torsional or bending deformation of the metal structure 20. The distance and overlapping area between the second signal acquisition circuit board 12 and the metal structure 20 in each second eddy current sensing region also change. Based on the eddy current effect, a second sine wave signal corresponding to each second eddy current sensing region is generated and output. The second sine wave signal corresponding to each second eddy current sensing region is used to characterize the torque around the X-axis. Torque around the Y-axis Torque around the Z-axis The three rotational components.

[0044] In this embodiment, the signal acquisition circuit board includes a first signal acquisition circuit board and a second signal acquisition circuit board. The first signal acquisition circuit board forms multiple first eddy current induction regions with the metal structural component, and the second signal acquisition circuit board forms multiple second eddy current induction regions with the metal structural component. When displacement occurs, the first signal acquisition circuit board generates and outputs a first sine wave signal corresponding to each of the first eddy current induction regions. The frequency of the first sine wave signal represents the three translational components of the force. Similarly, when displacement occurs, the second signal acquisition circuit board generates and outputs a second sine wave signal corresponding to each of the second eddy current induction regions. The frequency of the second sine wave signal represents the three rotational components of the force. This eliminates cross-interference between the translational and rotational components of the force, improving measurement accuracy.

[0045] As an optional implementation, the first signal acquisition circuit board 11 includes: a first signal acquisition circuit and a first planar coil Z-COIL.

[0046] When the AC signal passes through the first planar coil Z-COIL, the first signal acquisition circuit board 11 serves as the first electrode plate and the metal structure 20 serves as the second electrode plate. The first signal acquisition circuit board 11 and the metal structure 20 form multiple first equivalent inductances.

[0047] Optionally, continue to refer to Figure 2 The first signal acquisition circuit board 11 includes a first signal acquisition circuit and multiple first planar coils Z-COILs. The first signal acquisition circuit is a three-point LC resonant circuit. After power-on, when an AC signal passes through the first planar coils Z-COILs, the first signal acquisition circuit board 11 acts as the first electrode, and the metal structure 20 acts as the second electrode. The AC signal passing through the first planar coils Z-COILs generates an eddy current effect on the surface of the metal structure 20, forming multiple first equivalent inductances between the first signal acquisition circuit board 11 and the metal structure 20.

[0048] The first signal acquisition circuit is used to acquire the inductance change of each first equivalent inductor when the first signal acquisition circuit board 11 generates displacement, and to generate and output the first sine wave signal corresponding to each first equivalent inductor based on the inductance change of each first equivalent inductor.

[0049] Optionally, the first signal acquisition circuit acquires the inductance change of each first equivalent inductor when the first signal acquisition circuit board 11 is displaced. The inductance of each first equivalent inductor changes with the change in the distance and overlapping area between the first signal acquisition circuit board 11 and the metal structure 20 when the first signal acquisition circuit board 11 is displaced.

[0050] The first signal acquisition circuit generates and outputs a first sine wave signal corresponding to each first equivalent inductor based on the inductance change of each first equivalent inductor, so as to characterize the magnitude of the translation force, i.e., the three translation components of the force, through the frequency of the first sine wave signal.

[0051] The inductance of the first equivalent inductance is related to the distance between the first signal acquisition circuit board 11 and the metal structure 20 when the circuit board 11 is displaced. and overlapping area The relationship is expressed by the following formula:

[0052]

[0053] in, The first equivalent inductance is the inductance corresponding to the distance between the first signal acquisition circuit board 11 and the metal structure 20 when the first signal acquisition circuit board 11 is displaced. The first planar coil, Z-COIL, has its own inductance. The first proportionality constant is determined by the geometric parameters (number of turns, wire diameter, etc.) of the first planar coil Z-COIL and the material of the metal structural component 20. The distance between the first signal acquisition circuit board 11 and the metal structure 20 when the circuit board is displaced. The preset fit index, The first equivalent inductance is the inductance corresponding to the overlapping area between the first signal acquisition circuit board 11 and the metal structure 20 when the first signal acquisition circuit board 11 is displaced. The overlapping area between the first signal acquisition circuit board 11 and the metal structure 20 when the circuit board 11 is displaced.

[0054] Accordingly, the first sinusoidal signal corresponding to the first equivalent inductance generated by the first signal acquisition circuit includes the spacing-related frequency corresponding to the first equivalent inductance. and the frequency related to the overlapping area Among them, the spacing-related frequency corresponding to the first equivalent inductance. and the frequency related to the overlapping area All of these are oscillation frequencies.

[0055] The spacing-related frequency corresponding to the first equivalent inductance and the frequency related to the overlapping area The distance between the first signal acquisition circuit board 11 and the metal structure 20 when the circuit board 11 is displaced and overlapping area The relationship is expressed by the following formula:

[0056]

[0057] in, The pitch-related frequency corresponding to the first equivalent inductance. The frequency related to the overlapping area corresponding to the first equivalent inductance. The distance between the first equivalent inductance and the metal structure 20 when the first signal acquisition circuit board 11 is displaced. The corresponding inductance, The first equivalent inductance is the overlapping area between the first signal acquisition circuit board 11 and the metal structure 20 when the first signal acquisition circuit board 11 is displaced. The corresponding inductance. and It is the capacitor in the LC resonant circuit.

[0058] The frequency related to the spacing corresponding to the first equivalent inductance and the frequency related to the overlapping area The frequency change can accurately measure the magnitude of the translational force in the X, Y, and Z directions on the metal structural component 20.

[0059] In this embodiment, the first signal acquisition circuit board includes a first signal acquisition circuit and a first planar coil. When an AC signal passes through the first planar coil, the first signal acquisition circuit board acts as a first electrode plate, and the metal structural component acts as a second electrode plate. The first signal acquisition circuit board and the metal structural component form multiple first equivalent inductors. When the first signal acquisition circuit board undergoes displacement, the first signal acquisition circuit acquires the inductance change of each first equivalent inductor and generates and outputs a first sine wave signal corresponding to each first equivalent inductor based on the inductance change of each first equivalent inductor. By accurately acquiring the inductance change of each first equivalent inductor when the first signal acquisition circuit board undergoes displacement, the first signal acquisition circuit outputs the first sine wave signal corresponding to each first equivalent inductor. The three translational components of the force are determined by the frequency of the first sine wave signal.

[0060] As an optional implementation, the second signal acquisition circuit board 12 includes: a second signal acquisition circuit and a second planar coil T-COIL.

[0061] When the AC signal passes through the second planar coil T-COIL, the second signal acquisition circuit board 12 acts as the third electrode plate, and the metal structure 20 acts as the fourth electrode plate. The second signal acquisition circuit board 12 and the metal structure 20 form multiple second equivalent inductors.

[0062] Optionally, continue to refer to Figure 2 The second signal acquisition circuit board 12 includes a second signal acquisition circuit and multiple second planar coils T-COIL. The second signal acquisition circuit is also a three-point LC resonant circuit. After power-on, when the AC signal passes through the second planar coils T-COIL, the second signal acquisition circuit board 12 acts as the third plate, and the metal structure 20 acts as the fourth plate. The AC signal passing through the second planar coils T-COIL generates eddy currents on the surface of the metal structure 20, forming multiple second equivalent inductances between the second signal acquisition circuit board 12 and the metal structure 20.

[0063] The second signal acquisition circuit is used to acquire the inductance change of each second equivalent inductor when the second signal acquisition circuit board 12 generates displacement, and to generate and output the second sine wave signal corresponding to each second equivalent inductor based on the inductance change of each second equivalent inductor.

[0064] Optionally, the second signal acquisition circuit acquires the inductance change of each second equivalent inductor when the second signal acquisition circuit board 12 is displaced. The inductance of each second equivalent inductor changes with the change in the distance and overlapping area between the second signal acquisition circuit board 12 and the metal structure 20 when the second signal acquisition circuit board 12 undergoes torsional or bending deformation.

[0065] The second signal acquisition circuit generates and outputs a second sine wave signal corresponding to each second equivalent inductor based on the inductance change of each second equivalent inductor, so as to characterize the three rotational components of the force through the frequency of the second sine wave signal.

[0066] The inductance of the second equivalent inductor is related to the distance between the second signal acquisition circuit board 12 and the metal structure 20 when the circuit board 12 undergoes torsional or bending deformation. and overlapping area The relationship is expressed by the following formula:

[0067]

[0068] in, The second equivalent inductance is the inductance corresponding to the distance between the second signal acquisition circuit board 12 and the metal structure 20 when the second signal acquisition circuit board 12 is displaced. The inductance of the second planar coil T-COIL is its own. The second proportionality constant is determined by the geometric parameters (number of turns, wire diameter, etc.) of the second planar coil T-COIL and the material of the metal structural component 20. The distance between the second signal acquisition circuit board 12 and the metal structure 20 when it is twisted or bent. The preset fit index, The second equivalent inductance is the inductance corresponding to the overlapping area of ​​the second signal acquisition circuit board 12 and the metal structure 20 when the second signal acquisition circuit board 12 is twisted or bent. The overlapping area between the second signal acquisition circuit board 12 and the metal structure 20 when it is twisted or bent.

[0069] Accordingly, the second sinusoidal signal corresponding to the second equivalent inductance generated by the second signal acquisition circuit includes the spacing-related frequency corresponding to the second equivalent inductance. and the frequency related to the overlapping area Among them, the spacing-related frequency corresponding to the second equivalent inductance and the frequency related to the overlapping area All of these are oscillation frequencies.

[0070] The spacing-related frequency corresponding to the second equivalent inductance and the frequency related to the overlapping area The distance between the second signal acquisition circuit board 12 and the metal structure 20 when the circuit board twists or bends. and overlapping area The relationship is expressed by the following formula:

[0071]

[0072] in, The spacing-dependent frequency corresponding to the second equivalent inductance. The frequency corresponding to the overlapping area of ​​the second equivalent inductance. The distance between the second equivalent inductance and the metal structure 20 when the second signal acquisition circuit board 12 is twisted or bent. The corresponding inductance, The second equivalent inductance is the overlapping area of ​​the metal structure 20 when the second signal acquisition circuit board 12 is twisted or bent. The corresponding inductance. and It is the capacitor in the LC resonant circuit.

[0073] The frequency related to the spacing corresponding to the second equivalent inductance and the frequency related to the overlapping area The frequency change can be used to accurately measure the magnitude of the rotational torque in the X, Y, and Z directions on the metal structural component 20.

[0074] In this embodiment, the second signal acquisition circuit board includes a second signal acquisition circuit and a second planar coil. When an AC signal passes through the second planar coil, the second signal acquisition circuit board acts as the third electrode plate, and the metal structural component acts as the fourth electrode plate. The second signal acquisition circuit board and the metal structural component form multiple second equivalent inductors. When the second signal acquisition circuit board undergoes displacement, the second signal acquisition circuit acquires the inductance change of each second equivalent inductor and generates and outputs a second sine wave signal corresponding to each second equivalent inductor based on the inductance change of each second equivalent inductor. By accurately acquiring the inductance change of each second equivalent inductor when the second signal acquisition circuit board undergoes torsion or bending, the second signal acquisition circuit outputs the second sine wave signal corresponding to each second equivalent inductor. The frequency of the second sine wave signal determines the three rotational components of the force.

[0075] Figure 3 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 3 ,like Figure 3 As shown, the first signal acquisition circuit includes a first amplification module 13 and a first frequency selection module 14.

[0076] The power supply terminal of the first amplification module 13 is connected to the power supply voltage. The input terminal of the first amplification module 13 is connected to the first output terminal of the first frequency selection module 14. The first output terminal of the first amplification module 13 is connected to the input terminal of the first frequency selection module 14. The second output terminal of the first amplification module 13 is grounded. The second output terminal of the first frequency selection module 14 is grounded.

[0077] Optionally, refer to Figure 3 The first signal acquisition circuit is a three-point LC resonant circuit, including a first amplification module 13 and a first frequency selection module 14. The first amplification module 13 is used to provide initial gain, and the first frequency selection module 14 is used to select the frequency through the LC loop. When the first signal acquisition circuit is powered on, the noise signal is selected by the LC loop in the first frequency selection module 14 and amplified by the first amplification module 13 to gradually establish oscillation.

[0078] Specifically, the power supply terminal of the first amplification module 13 is connected to the power supply voltage, i.e., +VCC. The input terminal of the first amplification module 13 is connected to the first output terminal of the first frequency selection module 14 to amplify the feedback signal after frequency selection by the LC circuit in the first frequency selection module 14. The first output terminal of the first amplification module 13 is connected to the input terminal of the first frequency selection module 14, transmitting the amplified signal back to the LC circuit in the first frequency selection module 14 to gradually establish oscillation. The second output terminal of the first amplification module 13 and the second output terminal of the first frequency selection module 14 are both grounded.

[0079] In this embodiment, the first signal acquisition circuit includes a first amplification module and a first frequency selection module. The power supply terminal of the first amplification module is connected to a power supply voltage, its input terminal is connected to the first output terminal of the first frequency selection module, its first output terminal is connected to the input terminal of the first frequency selection module, its second output terminal is grounded, and its second output terminal is grounded. The first amplification module provides initial gain, and the first frequency selection module selects the frequency through an LC loop. When the first signal acquisition circuit is powered on, the noise signal is selectively fed back to the first amplification module by the LC loop in the first frequency selection module and amplified by the first amplification module, gradually establishing oscillation.

[0080] Figure 4 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 4 ,like Figure 4 As shown, the first signal acquisition circuit also includes a first coupling module 15 and a second coupling module 16.

[0081] The input terminal of the first coupling module 15 is connected to the first output terminal of the first frequency selection module 14, and the output terminal of the first coupling module 15 is connected to the input terminal of the first amplification module 13; the input terminal of the second coupling module 16 is connected to the first output terminal of the first amplification module 13, and the output terminal of the second coupling module 16 is connected to the input terminal of the first frequency selection module 14.

[0082] Optionally, refer to Figure 4 The first coupling module 15 is connected to the first amplification module 13 and the first frequency selection module 14 respectively. Specifically, the input terminal of the first coupling module 15 is connected to the first output terminal of the first frequency selection module 14, and the output terminal is connected to the input terminal of the first amplification module 13. The first coupling module 15 is used to couple the feedback signal after frequency selection by the first frequency selection module 14 through the LC loop to the input terminal of the first amplification module 13.

[0083] The input terminal of the second coupling module 16 is connected to the first output terminal of the first amplification module 13, and the output terminal is connected to the input terminal of the first frequency selection module 14. The second coupling module 16 is used to couple the signal amplified by the first amplification module 13 into the LC circuit of the first frequency selection module 14.

[0084] In this embodiment, the first signal acquisition circuit further includes a first coupling module and a second coupling module. The input terminal of the first coupling module is connected to the first output terminal of the first frequency selection module, and the output terminal is connected to the input terminal of the first amplification module; the input terminal of the second coupling module is connected to the first output terminal of the first amplification module, and the output terminal is connected to the input terminal of the first frequency selection module. The first coupling module couples the feedback signal after frequency selection by the first frequency selection module through the LC loop to the input terminal of the first amplification module, and the second coupling module couples the signal amplified by the first amplification module into the LC loop of the first frequency selection module.

[0085] Figure 5 A schematic diagram of the structure of the eddy current six-dimensional force sensor provided in the embodiments of this application. Figure 5 ,like Figure 5 As shown, the first amplification module 13 includes: a first transistor Q1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, and a first capacitor C1.

[0086] The base of the first transistor Q1 is connected to the output terminal of the first coupling module 15, the first terminal of the first resistor R1, and the first terminal of the second resistor R2. The collector of the first transistor Q1 is connected to the first terminal of the fourth resistor R4 and the input terminal of the second coupling module 16. The emitter of the first transistor Q1 is connected to one terminal of the third resistor R3 and one terminal of the first capacitor C1. The second terminals of the first resistor R1 and the fourth resistor R4 are connected to the power supply voltage. The second terminals of the second resistor R2, the third resistor R3, and the first capacitor C1 are grounded.

[0087] Optionally, refer to Figure 5 The base of the first transistor Q1 is connected to the output terminal of the first coupling module 15, the first terminal of the first resistor R1, and the first terminal of the second resistor R2, respectively. The collector is connected to the first terminal of the fourth resistor R4 and the input terminal of the first frequency selection module 14, respectively. The emitter is connected to one terminal of the third resistor R3 and one terminal of the first capacitor C1, respectively. The second terminal of the first resistor R1 and the second terminal of the fourth resistor R4 are connected to the power supply voltage +VCC. The second terminal of the second resistor R2, the second terminal of the third resistor R3, and the second terminal of the first capacitor C1 are grounded.

[0088] In the first amplification module 13, the first transistor Q1 is an amplification device used to amplify the feedback signal output from the LC circuit of the first frequency selection module 14 in order to maintain oscillation.

[0089] In this embodiment, the first amplification module includes a first transistor, a first resistor, a second resistor, a third resistor, a fourth resistor, and a first capacitor. The base of the first transistor is connected to the output terminal of the first coupling module, the first end of the first resistor, and the first end of the second resistor. The collector is connected to the first end of the fourth resistor and the input terminal of the second coupling module, respectively. The emitter is connected to one end of the third resistor and one end of the first capacitor, respectively. The second ends of the first and fourth resistors are connected to a power supply voltage, while the second ends of the second, third, and first resistors are grounded. The first transistor is an amplifying device that amplifies the feedback signal output from the LC circuit of the first frequency selection module to maintain oscillation.

[0090] As an optional implementation, the first frequency selection module 14 includes: a second capacitor C2, a third capacitor C3, and a first inductor, wherein the first inductor is one of a plurality of first equivalent inductors formed by the first signal acquisition circuit board 11 and the metal structure 20.

[0091] The first terminal of the second capacitor C2 and the first terminal of the first inductor are both connected to the output terminal of the second coupling module 16; the second terminal of the second capacitor C2 and the first terminal of the third capacitor C3 are grounded; the second terminal of the third capacitor C3 and the second terminal of the first inductor are both connected to the input terminal of the first coupling module 15.

[0092] Optionally, continue to refer to Figure 5 One of the multiple first equivalent inductors formed by the first signal acquisition circuit board 11 and the metal structure 20 is used as the first inductor in the first frequency selection module 14, and the second capacitor C2, the third capacitor C3 and the first inductor form an LC circuit.

[0093] Specifically, the first terminal of the second capacitor C2 and the first terminal of the first inductor are both connected to the output terminal of the second coupling module 16 to receive the amplified signal. The second terminal of the second capacitor C2 and the first terminal of the third capacitor C3 are grounded, and the second terminal of the third capacitor C3 and the second terminal of the first inductor are both connected to the input terminal of the first coupling module 15 to output a frequency-selected feedback signal to the first amplification module 13 through the first coupling module 15.

[0094] In this embodiment, the first frequency selection module includes a second capacitor, a third capacitor, and a first inductor. The first inductor is one of a plurality of first equivalent inductors formed by the first signal acquisition circuit board and the metal structural component. The first terminals of the second capacitor and the first inductor are both connected to the output terminal of the second coupling module. The second terminals of the second and third capacitors are grounded, and the second terminals of the third capacitor and the first inductor are both connected to the input terminal of the first coupling module. The second capacitor, the third capacitor, and the first inductor form an LC circuit, and the feedback signal after frequency selection by the LC circuit is coupled to the input terminal of the first amplification module through the first coupling module.

[0095] As an optional implementation, the first coupling module 15 includes a fourth capacitor C4.

[0096] The first terminal of the fourth capacitor C4 is connected to the first output terminal of the first frequency selection module 14; the second terminal of the fourth capacitor C4 is connected to the input terminal of the first amplification module 13.

[0097] Optionally, continue to refer to Figure 5The first terminal of the fourth capacitor C4 serves as the input terminal of the first coupling module 15 and is connected to the first output terminal of the first frequency selection module 14 to receive the feedback signal after frequency selection by the LC circuit of the first frequency selection module 14. The second terminal of the fourth capacitor C4 serves as the output terminal of the first coupling module 15 and is connected to the input terminal of the first amplification module 13 to couple the feedback signal after frequency selection by the LC circuit of the first frequency selection module 14 to the input terminal of the first amplification module 13, so that the first amplification module 13 amplifies the feedback signal after frequency selection by the LC circuit of the first frequency selection module 14.

[0098] In this embodiment, the first coupling module includes a fourth capacitor. The first end of the fourth capacitor is connected to the first output terminal of the first frequency selection module, and the second end is connected to the input terminal of the first amplification module. The fourth capacitor couples the frequency-selected feedback signal from the LC circuit of the first frequency selection module to the input terminal of the first amplification module, so that the first amplification module amplifies the frequency-selected feedback signal from the LC circuit of the first frequency selection module.

[0099] As an optional implementation, the second coupling module 16 includes a fifth capacitor C5.

[0100] The first terminal of the fifth capacitor C5 is connected to the first output terminal of the first amplification module 13; the second terminal of the fifth capacitor C5 is connected to the input terminal of the first frequency selection module 14.

[0101] Optionally, continue to refer to Figure 5 The first end of the fifth capacitor C5 serves as the input terminal of the second coupling module 16 and is connected to the first output terminal of the first amplification module 13 to receive the signal amplified by the first amplification module 13. The second end of the fifth capacitor C5 serves as the output terminal of the second coupling module 16 and is connected to the input terminal of the first frequency selection module 14 to couple the signal amplified by the first amplification module 13 to the LC circuit of the first frequency selection module 14, so that the LC circuit of the first frequency selection module 14 selects the frequency of the amplified signal and feeds it back to the first amplification module 13, gradually establishing oscillation.

[0102] In this embodiment, the second coupling module includes a fifth capacitor. The first end of the fifth capacitor is connected to the first output terminal of the first amplification module, and the second end is connected to the input terminal of the first frequency selection module. The signal amplified by the first amplification module is coupled to the LC circuit of the first frequency selection module through the fifth capacitor, so that the LC circuit of the first frequency selection module selects the frequency of the amplified signal and feeds it back to the first amplification module, gradually establishing oscillation.

[0103] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. An eddy current force sensor, characterized in that, include: Signal acquisition circuit boards and metal structural components; The signal acquisition circuit board is detachably connected to the metal structure, and multiple eddy current induction areas are formed between the signal acquisition circuit board and the metal structure. The metal structural component is used to deform under the action of force and drive the signal acquisition circuit board to generate displacement. The signal acquisition circuit board is used to generate and output sinusoidal signals corresponding to each eddy current induction region when displacement is generated. The frequency of the sinusoidal signal is used to characterize the magnitude of the six-dimensional components of the force.

2. The eddy current force sensor according to claim 1, characterized in that, The signal acquisition circuit board includes: a first signal acquisition circuit board and a second signal acquisition circuit board; Multiple first eddy current induction regions are formed between the first signal acquisition circuit board and the metal structural component; Multiple second eddy current induction regions are formed between the second signal acquisition circuit board and the metal structural component; The first signal acquisition circuit board is used to generate and output a first sine wave signal corresponding to each first eddy current induction region when displacement is generated. The frequency of the first sine wave signal is used to characterize the three translational components of the force. The second signal acquisition circuit board is used to generate and output a second sine wave signal corresponding to each second eddy current induction region when displacement is generated. The frequency of the second sine wave signal is used to characterize the three rotational components of the force.

3. The eddy current force sensor according to claim 2, characterized in that, The first signal acquisition circuit board includes: a first signal acquisition circuit and a first planar coil; When the AC signal passes through the first planar coil, the first signal acquisition circuit board acts as the first electrode plate, and the metal structural component acts as the second electrode plate. The first signal acquisition circuit board and the metal structural component form multiple first equivalent inductances. The first signal acquisition circuit is used to acquire the inductance change of each first equivalent inductor when the first signal acquisition circuit board is displaced, and to generate and output the first sine wave signal corresponding to each first equivalent inductor based on the inductance change of each first equivalent inductor.

4. The eddy current force sensor according to claim 2, characterized in that, The second signal acquisition circuit board includes: a second signal acquisition circuit and a second planar coil; When the AC signal passes through the second planar coil, the second signal acquisition circuit board acts as the third electrode plate, and the metal structural component acts as the fourth electrode plate. The second signal acquisition circuit board and the metal structural component form multiple second equivalent inductances. The second signal acquisition circuit is used to acquire the inductance change of each second equivalent inductor when the second signal acquisition circuit board is displaced, and to generate and output the second sine wave signal corresponding to each second equivalent inductor based on the inductance change of each second equivalent inductor.

5. The eddy current force sensor according to claim 3, characterized in that, The first signal acquisition circuit includes: a first amplification module and a first frequency selection module; The power supply terminal of the first amplification module is connected to the power supply voltage, the input terminal of the first amplification module is connected to the first output terminal of the first frequency selection module, the first output terminal of the first amplification module is connected to the input terminal of the first frequency selection module, and the second output terminal of the first amplification module is grounded. The second output terminal of the first frequency selection module is grounded.

6. The eddy current force sensor according to claim 5, characterized in that, The first signal acquisition circuit further includes: a first coupling module and a second coupling module; The input terminal of the first coupling module is connected to the first output terminal of the first frequency selection module, and the output terminal of the first coupling module is connected to the input terminal of the first amplification module. The input terminal of the second coupling module is connected to the first output terminal of the first amplification module, and the output terminal of the second coupling module is connected to the input terminal of the first frequency selection module.

7. The eddy current force sensor according to claim 6, characterized in that, The first amplification module includes: a first transistor, a first resistor, a second resistor, a third resistor, a fourth resistor, and a first capacitor; The base of the first transistor is connected to the output terminal of the first coupling module, the first terminal of the first resistor, and the first terminal of the second resistor. The collector of the first transistor is connected to the first terminal of the fourth resistor and the input terminal of the second coupling module. The emitter of the first transistor is connected to one end of the third resistor and one end of the first capacitor. The second terminal of the first resistor and the second terminal of the fourth resistor are connected to the power supply voltage; The second terminal of the second resistor, the second terminal of the third resistor, and the second terminal of the first capacitor are grounded.

8. The eddy current force sensor according to claim 6, characterized in that, The first frequency selection module includes: a second capacitor, a third capacitor, and a first inductor, wherein the first inductor is one of a plurality of first equivalent inductors formed by the first signal acquisition circuit board and the metal structure; The first terminal of the second capacitor and the first terminal of the first inductor are both connected to the output terminal of the second coupling module; The second terminal of the second capacitor and the first terminal of the third capacitor are grounded. The second terminal of the third capacitor and the second terminal of the first inductor are both connected to the input terminal of the first coupling module.

9. The eddy current force sensor according to claim 6, characterized in that, The first coupling module includes: a fourth capacitor; The first terminal of the fourth capacitor is connected to the first output terminal of the first frequency selection module; The second terminal of the fourth capacitor is connected to the input terminal of the first amplification module.

10. The eddy current force sensor according to claim 6, characterized in that, The second coupling module includes: a fifth capacitor; The first terminal of the fifth capacitor is connected to the first output terminal of the first amplification module; The second terminal of the fifth capacitor is connected to the input terminal of the first frequency selection module.

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