A force measuring device based on the height variation of three deformable circular elements

Abstract

The present invention relates to a force measuring device based on the height variation of three deformable circular elements. The device comprises a housing, three deformable circular elements, a load-bearing unit, a connecting plate, a plate pair, a base plate, a laser rangefinder, and a display control module. The base of the deformable circular elements is fixed to the base plate after being rotated through a specific angle. The deformable circular elements can change the height of their static configuration under the action of external forces. The load-bearing unit is mounted on top of the three deformable circular elements. The laser rangefinder is mounted on one side of the housing with its detection direction facing upward. The laser rangefinder is electrically connected to the display control module on the housing. The display control module calculates and determines the magnitude of the external force based on a predetermined functional relationship curve between the external force and the height of the three deformable circular elements. This technical solution provides a high-precision, lightweight, and economical force measurement solution, significantly improving the practicality and popularity of force measuring devices.

Description

Technical Field

[0001] The present invention relates to the technical field of force measurement, in particular to a force measuring device based on the height change of three deformable circular elements. Background Art

[0002] With the advancement of science and technology and the improvement of people's living standards, the demand for high-performance force measuring devices is increasing. These devices have been widely used in many fields such as industrial automation, medical diagnosis, food production, biomechanics, etc. Common force measuring devices include magnetic induction force measuring devices, piezoelectric force measuring devices, and fiber optic force measuring devices. Although these force measuring devices perform well in specific scenarios, they still face many challenges in terms of accuracy, weight, and cost. Current force measuring devices usually rely on complex sensor systems or mechanical structures to achieve force measurement, which not only makes the device heavier, but also makes the manufacturing and maintenance costs high, limiting its application in a wider range of fields. In addition, although some high-precision force measuring devices can provide reliable measurement results, their complex structure makes the operation and maintenance process cumbersome. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a force measuring device based on the height change of three deformable circular elements. Through its unique design, the force measuring device provides a high-precision, lightweight and economical force measuring solution, which significantly improves the practicality and popularity of the force measuring device.

[0004] To achieve the above-mentioned purpose, the present invention adopts the following technical solution: a force measuring device based on the height change of three deformable circular elements, comprising a housing (1), a first deformable circular element (9), a second deformable circular element (10), a third deformable circular element (11), a load bearing unit (18), a first connecting plate (3), a second connecting plate (4), a third connecting plate (5), a fourth connecting plate (6), a fifth connecting plate (7), a first plate pair (13), a second plate pair (14), a third plate pair (15), a fourth plate pair (16), a fifth plate pair (17), a bottom plate (12), a laser distance measuring device, The instrument (8) and the display control module (2) are provided, wherein the bottoms of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are fixed on the bottom plate (12) after being rotated, and are firmly fixed by the fourth connecting plate (6), the fifth connecting plate (7), the first plate pair (13), and the second plate pair (14); the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) change the height of their static configuration under the action of an external force, and different static configuration heights correspond to different external forces; the carrier The load bearing unit (18) is installed on the top of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11), and is integrated into one piece by the first connecting plate (3), the second connecting plate (4), the third connecting plate (5), the third plate pair (15), the fourth plate pair (16), and the fifth plate pair (17), so as to ensure that when an external force is applied, the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are subjected to force synchronously, thereby maintaining the consistency of height change; the laser rangefinder (8) is installed on The laser rangefinder (8) is electrically connected to a display control module (2) on the housing to transmit real-time measurement data to the display control module (2). The display control module (2) calculates and determines the magnitude of the external force based on a predetermined functional relationship curve between the external force and the heights of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11).

[0005] In a preferred embodiment, the functional relationship curve between the external force and the height of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is obtained by solving the static equilibrium equation of the three deformable circular elements;

[0006] The first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are deformed under the action of a vertical external force. Since the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) all follow the theoretical model between the external force and the displacement of the top of the circular element, a coordinate system is established at this time. The bottoms of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are fixed at the origin of the Cartesian coordinate system, and the tops are subjected to pressure or tension on the y-axis. In view of the fact that the subsequent theoretical analysis is similar for deformable circular elements when subjected to tension or pressure, pressure is used as an example for theoretical analysis. In the initial state without the action of external force, the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are not affected by internal force or torque. When pressure is applied, When at the top of the circular element, the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) generate internal force and torque to balance the pressure; as the pressure is applied, the heights of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) decrease until the system reaches a new equilibrium state; the energy functional of the right half of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is expressed as:

[0007]

[0008] Wherein, i=1, 2, 3 represent the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11), respectively; the bending stiffness K of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is i =EI i , E is the elastic modulus, I i is the corresponding moment of inertia, i=1, 2, 3; respectively determined by the elastic modulus and the moment of inertia; s1, s2 and s3 respectively represent the arc lengths of the first deformable circular element (9), the second deformable circular element (10) and the third deformable circular element (11), the bottom of the first deformable circular element (9), the second deformable circular element (10) and the third deformable circular element (11). and is the origin of the natural coordinates; the deflection angles of any point on the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) relative to the x-axis are expressed by θ1(s1), θ2(s2), and θ3(s3), respectively, and θ'i (s i )=dθ i / ds i (i=1,2,3) represents the curvature, and the component of the internal force along the x direction is given by and The three components of the pressure applied to the top of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are respectively and The internal moment at the bottom of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is given by The internal moment at the top is represented by M(πR i )=K i θ' i (πR i )(i=1,2,3); the constraint condition in the energy functional reflects the symmetry of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) with respect to the y-axis; finally, the energy functional is restated as:

[0009]

[0010] Where, Right now Where ξ1, ξ2 and ξ3 are different small positive parameters, and the first-order variation of W is expressed as:

[0011]

[0012] Taking into account the arbitrariness of η1(s1), η2(s2) and η3(s3), the equilibrium equations for the right half of the first deformable circular element (9), the second deformable circular element (10) and the third deformable circular element (11) are derived as follows:

[0013]

[0014] Where i = 1, 2, 3; In addition, the deformable circular element satisfies the non-stretchable condition

[0015] x i ′(s i )=cosθ i (s i ),y i ′(s i )=sinθ i (s i )

[0016] By combining the following conditions, the equilibrium configurations of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) under different external forces are numerically solved; first, a differential equation group and a continuity condition are considered, wherein the continuity condition includes variables (θ1, θ'1, x1, y1, θ2, θ'2, x2, y2, θ3, θ'3, x3, y3); the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) should be continuous; in addition, the boundary conditions must also be met: θ i (0)=0,y i (0)=0,x i (0)=0,x i (πR i )=0,θ i (πR i )=π(i=1,2,3), and numerically solve the equilibrium states of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) by integrating the continuity conditions;

[0017] According to the above equation, the relationship between the displacement of the top of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) and the applied pressure is derived; the initial heights of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are 2R1, 2R2, and 2R3, respectively; due to their connection structure, under the partial pressure and Under the action of the partial pressures, the tops of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) will undergo the same downward displacement; by numerically solving the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) under the application of these partial pressures, the displacement Δy of the tops of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is further calculated:

[0018]

[0019] Where i = 1, 2, 3;

[0020] The displacement and applied pressure of the top of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are derived. and The relationship between the pressure applied by the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is determined by measuring the displacement of the top of the circular element. Since the displacements of the tops of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are the same, the total pressure is indirectly calculated by accumulating the pressures applied to the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11). A similar approach is also applicable to analyzing tension situations.

[0021] In a preferred embodiment, by adjusting the bending stiffness of the deformable circular element, the functional relationship between the top displacement of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) and the applied external force can be changed, thereby achieving the adjustment of the measurement range of the force measuring device.

[0022] In a preferred embodiment, the display control module (2) comprises a display screen, which is embedded in one side of the housing, and the display control module displays the calculated external force value on the display screen.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The force measuring device measures external forces based on the principle that three deformable circular elements change their static configuration height under the action of external forces. It has a simple structure and low production cost, is lightweight and easy to operate, and exhibits high accuracy and reliability during the measurement process.

[0025] (2) To accommodate different measurement ranges, the force measuring device can be manufactured by adjusting the dimensional parameters of the three deformable circular elements or using materials with a larger elastic modulus. This flexibility enables the device to meet a variety of measurement requirements.

[0026] (3) The force measuring device has excellent structural stability and a long service life. It has high repeatability, strong environmental adaptability, and is very easy to install and replace. These characteristics make the device highly durable and easy to maintain in practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 1 is a schematic diagram of the structure of a force measuring device according to an embodiment of the present invention;

[0028] Figure 2 1 is a schematic diagram of the overall structure of a force measuring device according to an embodiment of the present invention;

[0029] Figure 3Schematic diagram of the connection structure of the first deformable circular element, the second deformable circular element, and the third deformable circular element inside the force measuring device in an embodiment of the present invention;

[0030] Figure 4 1 is a force analysis diagram of the first deformable circular element, the second deformable circular element, and the third deformable circular element under pressure in an embodiment of the present invention;

[0031] Figure 5 is a force analysis diagram of the first deformable circular element, the second deformable circular element, and the third deformable circular element under tension in an embodiment of the present invention;

[0032] Figure 6 Graph showing the functional relationship between the displacement changes of the first deformable circular element, the second deformable circular element, and the third deformable circular element and the external force in the embodiment. DETAILED DESCRIPTION

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0035] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form, and it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0036] like Figure 1-6As shown, this embodiment provides a force measuring device based on the height change of three deformable circular elements, including a housing 1, a first deformable circular element 9, a second deformable circular element 10, a third deformable circular element 11, a load-bearing unit 18, a first connecting plate 3, a second connecting plate 4, a third connecting plate 5, a fourth connecting plate 6, a fifth connecting plate 7, a first plate pair 13, a second plate pair 14, a third plate pair 15, a fourth plate pair 16, a fifth plate pair 17, a base plate 12, a laser rangefinder 8 and a display control module 2. The bottoms of the first deformable circular element 9, the second deformable circular element 10 and the third deformable circular element 11 are fixed to the base plate after being rotated by a specific angle, and are firmly fixed by the fourth connecting plate 6, the fifth connecting plate 7 and the first plate pair 13 and the second plate pair 14; the first deformable circular element 9, the second deformable circular element 10 and the third deformable circular element 11 can change the height of their static configuration under the action of external force, and at different The load-bearing unit 18 is mounted on the top of the three deformable circular elements and is integrated into one body through the first connecting plate 3, the second connecting plate 4, the third connecting plate 5 and the third plate pair 15, the fourth plate pair 16, and the fifth plate pair 17 to ensure that when an external force is applied, the first deformable circular element 9, the second deformable circular element 10, and the third deformable circular element 11 can be subjected to force synchronously, thereby maintaining consistency in height changes. The laser rangefinder 8 is mounted on one side of the housing 1 with its detection direction facing upward to measure changes in the height of the deformable circular elements. The laser rangefinder 8 is electrically connected to the display control module 2 on the housing to transmit real-time measurement data to the display control module. The display control module 2 calculates and determines the magnitude of the external force based on a predetermined functional relationship curve between the external force and the heights of the first deformable circular element 9, the second deformable circular element 10, and the third deformable circular element 11.

[0037] In this embodiment, the functional relationship curve between the external force and the height of the first deformable circular element 9, the second deformable circular element 10, and the third deformable circular element 11 is obtained by solving the static equilibrium equation of the first deformable circular element 9, the second deformable circular element 10, and the third deformable circular element 11;

[0038] like Figure 4 、 5As shown, the first deformable circular element 9, the second deformable circular element 10, and the third deformable circular element 11 are deformed under the action of a vertical external force. Since each deformable circular element follows the theoretical model between the external force and the displacement of the top of the circular element, a coordinate system is established at this time. The bottoms of the first deformable circular element 9, the second deformable circular element 10, and the third deformable circular element 11 are fixed at the origin of the Cartesian coordinate system, and the tops are subjected to pressure or tension on the y-axis. In view of similar theoretical analysis for deformable circular elements when they are subjected to tension or pressure, pressure is used as a case for theoretical analysis. At the same time, taking into account the symmetry of the deformable circular element with respect to the y-axis, in order to simplify the analysis, we only study the configuration of its right half. In the initial state without external force, the three deformable circular elements are not affected by internal forces or torques. When pressure is applied When the circular element is placed on top of the circular element, the three deformable circular elements generate internal forces and torques to balance the pressure. As pressure is applied, the height of the circular element decreases until the system reaches a new equilibrium state. At this point, the energy functional of the right half of the three deformable circular elements can be expressed as:

[0039]

[0040] Where i = 1, 2, 3 represent three deformable circular elements. The bending stiffness K of each deformable circular element is i =EI i (E is the elastic modulus, I i is the corresponding moment of inertia, i = 1, 2, 3) is determined by the elastic modulus and moment of inertia respectively. s1, s2 and s3 are the arc lengths of the three circular elements. The bottom of each circular element is and The deflection angle of any point on each circular element relative to the x-axis is expressed by θ1(s1), θ2(s2) and θ3(s3), respectively. i (s i )=dθ i / ds i (i=1,2,3) represents the curvature, and the component of the internal force along the x direction is given by and The three components of the pressure applied to the top of the circular element are and The internal moment at the bottom of the circular element is given by The internal moment at the top is represented by M(πR i )=K i θ' i (πR i)(i=1,2,3). The constraints in the energy functional reflect the symmetry of the circular element with respect to the y-axis. Finally, the energy functional can be reformulated as:

[0041]

[0042] Where, Assume that each circular element curve undergoes a small virtual deformation, i.e. Where ξ1, ξ2 and ξ3 are different small positive parameters, the first-order variation of W can be expressed as:

[0043]

[0044] Taking into account the arbitrariness of η1(s1), η2(s2) and η3(s3), the equilibrium equations for the right half of the three deformable circular elements are derived as follows:

[0045]

[0046] Where i = 1, 2, 3. In addition, the deformable circular element satisfies the non-stretchable condition

[0047] x i ′(s i )=cosθ i (s i ),y i ′(s i )=sinθ i (s i )

[0048] By combining the following conditions, the equilibrium configurations of the three deformable circular elements under different external forces can be numerically solved. First, the system of differential equations and the continuity conditions are considered. These conditions include that the variables (θ1, θ'1, x1, y1, θ2, θ'2, x2, y2, θ3, θ'3, x3, y3) should be continuous on each deformable circular element. In addition, the boundary conditions must be met: θ i (0)=0,y i (0)=0,x i (0)=0,x i (πR i )=0,θ i (πR i )=π(i=1,2,3), and by integrating these conditions, the equilibrium state of the three deformable circular elements can be numerically solved;

[0049] In this embodiment, the radius of the third deformable circular element 11 is 2 cm, the thickness is 0.62 mm, the width is 1.6 cm, and the elastic modulus is 2.75 GPa; the radius of the second deformable circular element 10 is 3 cm, the thickness is 0.94 mm, the width is 1.8 cm, and the elastic modulus is 2.75 GPa; the radius of the first deformable circular element 9 is 4 cm, the thickness is 1.26 mm, the width is 2 cm, and the elastic modulus is 2.75 GPa; the overall length of the entire force sensor is 120 mm, the width is 100 mm, and the height is 120 mm.

[0050] According to the above equation, the relationship between the top displacement of the deformable circular element and the applied pressure can be derived. The initial heights of the three deformable circular elements are 2R1, 2R2 and 2R3 respectively. Due to their connection structure, the partial pressure and Under the action of , the tops of these deformable circular elements will have the same downward displacement. By numerically solving the deformable circular elements under these partial pressures, the displacement Δy of the tops of the deformable circular elements can be further calculated:

[0051]

[0052] Wherein, i=1, 2, 3.

[0053] The displacement of the top of the three deformable circular elements and the applied pressure can be deduced from the equation and The relationship between the top displacement of the circular element and the applied pressure can be indirectly determined by measuring the displacement of the top of the circular element. Since the displacement of the tops of the three deformable circular elements is the same, the total pressure can be indirectly calculated by adding the pressures on the three deformable circular elements. A similar approach is also applicable to analyzing tension situations.

[0054] like Figure 6 As shown, the displacement of the top of the three deformable circular elements shows a nonlinear relationship with the applied external force. It can be concluded that the pressure measurement range of the force sensor is 0-18N, the measurement accuracy is 1.9%, and the tension measurement range is 0-26N, and the measurement accuracy is 1.7%.

[0055] By changing the bending stiffness of the elastic circle, the functional relationship between the first deformable circular element 9, the second deformable circular element 10, the third deformable circular element 11 and the applied external force can be changed, thereby adjusting the measuring range of the force measuring device.

[0056] From the above analysis, it can be seen that the force measuring device provided by the present invention can accurately measure external forces. When no external force is applied, the load-bearing unit 18 is in its original state, and the laser rangefinder 8 measures the initial heights of the first deformable circular element 9, the second deformable circular element 10, and the third deformable circular element 11. When an external force is applied to the load-bearing unit, the heights of the first deformable circular element 9, the second deformable circular element 10, and the third deformable circular element 11 will change in a consistent manner. At this time, the laser rangefinder 8 measures the height of the deformable circular elements after the external force is applied, and transmits the changed height data to the display control module 2. The display control module 2 performs calculations based on the nonlinear relationship between the displacement of the tops of the three deformable circular elements and the applied external force, thereby determining the applied external force and displaying the calculation results on the display screen of the display control module 2.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other manner. Any person skilled in the art may utilize the above-disclosed technical content to modify or modify the present invention into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention remain within the scope of protection of the present invention.

Claims

1. A force measuring device based on the height variation of three deformable circular elements, characterized in that: The invention comprises a housing (1), a first deformable circular element (9), a second deformable circular element (10), a third deformable circular element (11), a load bearing unit (18), a first connecting plate (3), a second connecting plate (4), a third connecting plate (5), a fourth connecting plate (6), a fifth connecting plate (7), a first plate pair (13), a second plate pair (14), a third plate pair (15), a fourth plate pair (16), a fifth plate pair (17), a bottom plate (12), a laser rangefinder (8) and a display control module (2), wherein the first deformable circular element (9), the second deformable circular element (10), the third deformable circular element (11) and the load bearing unit (18) are connected to each other. The bottoms of the deformable circular element (10) and the third deformable circular element (11) are fixed on the bottom plate (12) after being rotated, and are firmly fixed by the fourth connecting plate (6), the fifth connecting plate (7), the first plate pair (13), and the second plate pair (14); the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) change the height of their static configuration under the action of external force, and different static configuration heights correspond to different external forces; the load bearing unit (18) is installed on the first deformable circular element The first deformable circular element (9), the second deformable circular element (10), and the top of the third deformable circular element (11) are connected to each other and integrated into one piece by a first connecting plate (3), a second connecting plate (4), a third connecting plate (5), a third plate pair (15), a fourth plate pair (16), and a fifth plate pair (17) to ensure that when an external force is applied, the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are subjected to force synchronously, thereby maintaining the consistency of height change; the laser rangefinder (8) is installed on one side of the housing (1), and its The detection direction is upward to measure the height changes of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11); the laser rangefinder (8) is electrically connected to the display control module (2) on the housing to transmit real-time measurement data to the display control module (2); the display control module (2) calculates and determines the magnitude of the external force based on a predetermined functional relationship curve between the external force and the heights of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11).

2. A force measuring device based on height variation of three deformable circular elements according to claim 1, characterized in that: The functional relationship curve between the external force and the height of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is obtained by solving the static equilibrium equations of the three deformable circular elements; The first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are deformed under the action of a vertical external force. Since the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) all follow the theoretical model between the external force and the displacement of the top of the circular element, a coordinate system is established at this time. The bottoms of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are fixed at the origin of the Cartesian coordinate system, and the tops are subjected to pressure or tension on the y-axis. In view of the fact that the subsequent theoretical analysis is similar for deformable circular elements when subjected to tension or pressure, pressure is used as an example for theoretical analysis. In the initial state without the action of external force, the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are not affected by internal force or torque. When pressure is applied, When at the top of the circular element, the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) generate internal force and torque to balance the pressure; as the pressure is applied, the heights of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) decrease until the system reaches a new equilibrium state; the energy functional of the right half of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is expressed as: Wherein, i=1, 2, 3 represent the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11), respectively; the bending stiffness K of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is i =EI i , E is the elastic modulus, I i is the corresponding moment of inertia, i=1, 2, 3; respectively determined by the elastic modulus and the moment of inertia; s1, s2 and s3 respectively represent the arc lengths of the first deformable circular element (9), the second deformable circular element (10) and the third deformable circular element (11), the bottom of the first deformable circular element (9), the second deformable circular element (10) and the third deformable circular element (11). and is the origin of the natural coordinates; the deflection angles of any point on the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) relative to the x-axis are expressed by θ1(s1), θ2(s2), and θ3(s3), respectively, and θ′ i (s i )=dθ i / ds i (i=1,2,3) represents the curvature, and the component of the internal force along the x direction is given by and The three components of the pressure applied to the top of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are respectively and The internal moment at the bottom of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is given by The internal moment at the top is represented by M(πR i )=K i θ′ i (πR i )(i=1,2,3); the constraint condition in the energy functional reflects the symmetry of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) with respect to the y-axis; finally, the energy functional is restated as: Where, Right now Where ξ1, ξ2 and ξ3 are different small positive parameters, and the first-order variation of W is expressed as: Taking into account the arbitrariness of η1(s1), η2(s2) and η3(s3), the equilibrium equations for the right half of the first deformable circular element (9), the second deformable circular element (10) and the third deformable circular element (11) are derived as follows: Where i = 1, 2, 3; In addition, the deformable circular element satisfies the non-stretchable condition x′ i (s i )=cosθ i (s i ),y′ i (s i )=sinθ i (s i ) By combining the following conditions, the equilibrium configurations of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) under different external forces are numerically solved; first, a differential equation group and a continuity condition are considered, wherein the continuity condition includes variables (θ1, θ′1, x1, y1, θ2, θ′2, x2, y2, θ3, θ′3, x3, y3); the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) should be continuous; in addition, the boundary conditions must also be met: θ i (0)=0,y i (0)=0,x i (0)=0,x i (πR i )=0,θ i (πR i )=π(i=1, 2, 3), and numerically solving the equilibrium states of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) by integrating the continuity conditions; The relationship between the top displacement of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) and the applied pressure is derived; the initial heights of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are 2R1, 2R2, and 2R3, respectively; due to their connection structure, under partial pressure and Under the action of the partial pressures, the tops of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) will undergo the same downward displacement; by numerically solving the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) under the application of these partial pressures, the displacement Δy of the tops of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is further calculated: Where i = 1, 2, 3; The displacement and applied pressure of the top of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are derived. and The relationship between the pressure applied by the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) is determined by measuring the displacement of the top of the circular element. Since the displacements of the tops of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) are the same, the total pressure is indirectly calculated by accumulating the pressures applied to the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11).

3. A force measuring device based on height variation of three deformable circular elements according to claim 2, characterized in that: By adjusting the bending stiffness of the deformable circular element and changing the functional relationship between the top displacement of the first deformable circular element (9), the second deformable circular element (10), and the third deformable circular element (11) and the applied external force, the measurement range of the force measuring device can be adjusted.

4. A force measuring device based on height variation of three deformable circular elements according to claim 1, characterized in that: The display control module (2) comprises a display screen embedded in one side of the housing, and the display control module displays the calculated external force value on the display screen.

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