A kind of integrated cross beam type six-dimensional force sensor elastomer

Abstract

The application relates to the technical field of sensors and discloses an integrated cruciform beam type six-dimensional force sensor elastic body which comprises an integrated outer ring annular fixed base, a center loading table and four elastic sensitive beams; the outer ring annular fixed base is a flange type annular structure, and mounting through holes for sensor fixed mounting are uniformly distributed on the circumference of the outer ring annular fixed base; the center loading table is located at the center axis position of the outer ring annular fixed base, the application can paste resistance strain gauges in different strain sensitive areas and form a Wheatstone full-bridge circuit, three-direction force signals and three-direction torque signals are respectively collected, six-dimensional force structure decoupling is realized, the mutual interference of inter-dimension forces is effectively reduced, the decoupling precision and the measurement precision are improved, and the elastic body can improve the dynamic response performance of the sensor while ensuring the overall structure rigidity.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and in particular to an integrated crossbeam type six-dimensional force sensor elastomer. Background Technology

[0002] Six-dimensional force sensors can simultaneously detect forces (Fx, Fy, Fz) in three directions and torques (Mx, My, Mz) in three directions within a spatial coordinate system. They are core components for acquiring force feedback information in fields such as robot interaction, precision assembly, aerospace, and intelligent manufacturing. The elastic body, as the core sensing element of the six-dimensional force sensor, directly determines the sensor's key performance indicators such as stiffness, sensitivity, decoupling performance, and dynamic characteristics through its structural form.

[0003] Currently, various structural forms of six-dimensional force sensor elastomers have been developed both domestically and internationally. Typical structures include cross-beam structures, Stewart platform structures, and layered ring structures. Among them, the layered ring structure six-dimensional force sensor elastomer (such as the invention patent with publication number CN106768522A) achieves force measurement through a combination of radial beams, circumferential beams, and circumferential supports. However, this type of structure usually suffers from problems such as a large number of component layers, high processing and assembly difficulty, and insufficient structural compactness.

[0004] On the other hand, while conventional cross-beam elastomers are relatively simple in structure, they generally suffer from the problem of balancing stiffness and sensitivity, and exhibit severe interdimensional coupling during multidimensional force measurement, making it difficult to simultaneously meet the requirements of high dynamic response and high-precision measurement. Therefore, designing a six-dimensional force sensor elastomer that is simple in structure, balances stiffness and sensitivity, and has good decoupling performance has significant engineering application value for improving the overall performance of six-dimensional force sensors. Summary of the Invention

[0005] The purpose of this invention is to solve the problems of complex structure, high processing difficulty, difficulty in balancing stiffness and sensitivity, and severe interdimensional coupling in existing six-dimensional force sensor elastomers. The invention proposes an integrated crossbeam type six-dimensional force sensor elastomer, which improves detection sensitivity while ensuring high stiffness and dynamic performance of the sensor, and achieves a simple and compact structure, integrated processing and convenient installation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] An integrated cross-beam type six-dimensional force sensor elastomer includes an integrally formed outer ring fixing base, a central loading platform, and four elastic sensing beams.

[0008] The outer ring fixing base is a flange-type ring structure, and mounting through holes for fixing and installing the sensor are evenly distributed on the circumference of the outer ring fixing base.

[0009] The central loading platform is located at the central axis of the outer ring fixed base and is used to receive and load the measured six-dimensional spatial force and torque.

[0010] The four elastic sensitive beams are evenly orthogonally distributed on the circumference of the outer ring fixed base, and adjacent elastic sensitive beams are perpendicular to each other;

[0011] The inner end of the elastic sensitive beam is fixedly connected to the side of the central loading platform, and the outer end of the elastic sensitive beam is fixedly connected to the inner wall of the outer ring fixed base, so that the elastic sensitive beam forms a cross-spoke symmetrical support structure between the central loading platform and the outer ring fixed base.

[0012] Each of the elastic sensitive beams is provided with strain concentration through holes, which are used to concentrate the stress of the elastic sensitive beams into the strain sensitive areas on both sides of the strain concentration through holes. The strain sensitive areas are used to attach resistance strain gauges to collect strain signals.

[0013] Preferably, the central loading platform is a regular quadrilateral block structure, and the four elastic sensitive beams are fixedly connected to the four sides of the central loading platform respectively.

[0014] Preferably, the end face of the central loading stage is provided with four threaded mounting holes for connecting and fixing with the test piece and a weight-reducing through hole.

[0015] Preferably, the strain concentration through-hole is a horizontal through-hole penetrating both sides of the elastic sensitive beam, and / or a vertical through-hole penetrating the upper and lower surfaces of the elastic sensitive beam.

[0016] Preferably, the strain concentration through hole is any one of a cylindrical hole, an elliptical cylindrical hole, and a waist-shaped cylindrical hole.

[0017] Preferably, each of the elastic sensitive beams has two sets of strain concentration through holes, one set of which is located at the inner end of the elastic sensitive beam and the other set of which is located at the outer end of the elastic sensitive beam.

[0018] Preferably, each of the elastic sensitive beams is provided with four strain concentration through holes, which are divided into two groups: one horizontal through hole and three vertical through holes. The horizontal through hole is close to the inner end of the elastic sensitive beam connected to the central loading platform, and the three vertical through holes are close to the outer end of the elastic sensitive beam connected to the outer ring fixed base.

[0019] Preferably, the elastic sensitive beam is a rectangular beam with a uniform cross-section, or a variable cross-section beam that is wide at both ends and narrow in the middle along its length.

[0020] Preferably, the elastomer is made of aerospace aluminum alloy, stainless steel or titanium alloy and is formed by one-piece milling.

[0021] The beneficial effects of this invention are as follows:

[0022] 1. This invention achieves structural decoupling of six-dimensional forces. By employing an orthogonal symmetrical cross-spoke structure, with four elastic sensitive beams distributed perpendicularly in pairs, resistance strain gauges can be attached to different strain-sensitive regions to form a Wheatstone full-bridge circuit. This circuit collects force signals and torque signals in three directions, respectively, thereby achieving structural decoupling of six-dimensional forces. This effectively reduces mutual interference between forces in different dimensions and improves decoupling and measurement accuracy.

[0023] 2. This invention effectively balances the stiffness and sensitivity of the sensor. Through an integrated cross-spoke structure design, the elastomer maintains overall structural stiffness while enhancing the sensor's dynamic response performance. Simultaneously, strain-concentrating through-holes are incorporated into the elastic sensitive beam, concentrating strain in the strain-sensitive area. This improves detection sensitivity without reducing structural stiffness, thus achieving a balance between stiffness and sensitivity and addressing the difficulty of achieving both in traditional elastomers.

[0024] 3. The present invention has a simple and compact structure, and is convenient to process and install. The elastomer of the present invention adopts an integrated structural design, which can be formed by one-time milling without assembly, avoiding the loss of precision caused by assembly errors and reducing processing costs and cycle time; the outer ring fixed base adopts a flange structure, which can be used to fix the sensor by bolts, with strong adaptability and convenient installation; compared with the layered ring structure, the present invention has fewer structural layers, smaller volume, and lower processing difficulty.

[0025] 4. The invention has good structural symmetry and strong resistance to eccentric loads. The overall structure of the invention has good symmetry and strong resistance to eccentric loads. By rationally arranging the positions of the elastic sensitive beams, the force and moment action paths in all directions are balanced, which is beneficial to improving structural stability and measurement consistency. It can be applied to six-dimensional force measurement under complex working conditions such as robotics and precision assembly. Attached Figure Description

[0026] Figure 1 This is a three-dimensional structural diagram of an integrated crossbeam-type six-dimensional force sensor elastomer proposed in an embodiment of the present invention;

[0027] Figure 2 This is a front structural schematic diagram of an integrated crossbeam-type six-dimensional force sensor elastomer proposed in an embodiment of the present invention.

[0028] In the figure: 1-Outer ring fixed base, 2-Central loading platform, 3-Elastic sensitive beam, 4-Mounting through hole, 5-Strain concentration through hole, 6-Threaded mounting hole, 7-Weight reduction through hole. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0030] Reference Figures 1 to 2 An integrated cross-beam type six-dimensional force sensor elastomer includes an integrally formed outer ring fixed base 1, a central loading platform 2, and four elastic sensitive beams 3.

[0031] The outer ring fixing base 1 is a flange-type ring structure. The outer ring fixing base 1 has mounting through holes 4 evenly distributed on its circumference for fixing and installing the sensor. In this embodiment, there are 8 mounting through holes 4, and the sensor can be fixedly installed on the mounting base by bolts.

[0032] The central loading platform 2 is a regular quadrilateral block structure located at the central axis of the outer ring fixed base 1. The end face of the central loading platform 2 is provided with four threaded mounting holes 6 for fixed connection with the test piece and for bearing and loading the measured spatial six-dimensional force and torque. The central loading platform 2 is also provided with a weight reduction through hole 7.

[0033] The four elastic sensitive beams 3 are evenly orthogonally distributed on the circumference of the outer ring fixed base 1, and adjacent elastic sensitive beams 3 are perpendicular to each other, forming a cross-shaped structure.

[0034] The inner ends of the four elastic sensitive beams 3 are fixedly connected to the four sides of the central loading platform 2 one by one, and the outer ends of the elastic sensitive beams 3 are fixedly connected to the inner wall of the outer ring fixed base 1, so that the elastic sensitive beams 3 form a cross-spoke symmetrical support structure between the central loading platform 2 and the outer ring fixed base 1.

[0035] Each of the elastic sensitive beams 3 is provided with a strain concentration through hole 5, which is used to concentrate the stress of the elastic sensitive beam 3 on the strain sensitive area on both sides of the strain concentration through hole 5. The strain sensitive area is used to attach resistance strain gauges to collect strain signals.

[0036] In a preferred embodiment of the present invention, the strain concentration through hole 5 is a horizontal through hole penetrating both sides of the elastic sensitive beam 3, and / or a vertical through hole penetrating the upper and lower surfaces of the elastic sensitive beam 3.

[0037] In a preferred embodiment of the present invention, the strain concentration through hole 5 is any one of a cylindrical hole, an elliptical cylindrical hole, and a waist-shaped cylindrical hole.

[0038] In a preferred embodiment of the present invention, each elastic sensitive beam 3 has two sets of strain concentration through holes 5, one set of strain concentration through holes 5 is located at the inner end of the elastic sensitive beam 3, and the other set of strain concentration through holes 5 is located at the outer end of the elastic sensitive beam 3.

[0039] In a preferred embodiment of the present invention, each of the elastic sensitive beams 3 is provided with four strain concentration through holes 5. The four strain concentration through holes 5 are divided into two groups: one horizontal through hole and three vertical through holes. The horizontal through hole is close to the inner end of the elastic sensitive beam 3 connected to the central loading platform 2, and the three vertical through holes are close to the outer end of the elastic sensitive beam 3 connected to the outer ring fixed base 1.

[0040] In a preferred embodiment of the present invention, the elastic sensitive beam 3 is a rectangular beam with a uniform cross-section, or a variable cross-section beam that is wide at both ends and narrow in the middle along the length direction.

[0041] In a preferred embodiment of the present invention, the elastomer is made of aerospace aluminum alloy, stainless steel or titanium alloy and is formed by one-piece milling.

[0042] In a preferred embodiment of the present invention, the elastomer may be made of materials such as 7075 aerospace aluminum alloy, 304 stainless steel or TC4 titanium alloy.

[0043] In use, resistance strain gauges are attached to the strain-sensitive areas of each elastic sensitive beam 3 to form six sets of Wheatstone full-bridge circuits, which are used to collect force signals in the three directions of Fx, Fy, and Fz, and torque signals in the three directions of Mx, My, and Mz, respectively. When the six-dimensional force or torque to be measured is applied to the central loading stage 2, the elastic sensitive beam 3 deforms, and the strain gauges convert the deformation into resistance changes, which are then output as corresponding electrical signals through the Wheatstone bridge to realize the measurement of the six-dimensional force and torque. The orthogonal and symmetrical arrangement of the structure effectively reduces the mutual interference between the dimensions.

[0044] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An integrated cross-beam type six-dimensional force sensor elastomer, characterized in that, It includes an integrally formed outer ring fixed base (1), a central loading platform (2), and four elastic sensitive beams (3); The outer ring fixed base (1) is a flange-type ring structure with mounting through holes (4) evenly distributed on its circumference for fixing and installing the sensor. The central loading platform (2) is located at the central axis of the outer ring fixed base (1); The four elastic sensitive beams (3) are evenly distributed on the circumference of the outer ring fixed base (1) and are adjacent to each other perpendicularly; The inner end of the elastic sensitive beam (3) is fixedly connected to the side of the central loading platform (2), and the outer end of the elastic sensitive beam (3) is fixedly connected to the inner wall of the outer ring fixed base (1) to form a cross-spoke symmetrical support structure. Each of the elastic sensitive beams (3) is provided with a strain concentration through hole (5) to concentrate the stress of the elastic sensitive beam (3) on the strain sensitive area on both sides of the strain concentration through hole (5).

2. The integrated cross-beam type six-dimensional force sensor elastomer according to claim 1, characterized in that, The central loading platform (2) is a regular quadrilateral block structure, and the four elastic sensitive beams (3) are fixedly connected to the four sides of the central loading platform (2) respectively.

3. The integrated cross-beam type six-dimensional force sensor elastomer according to claim 1, characterized in that, The end face of the central loading platform (2) is provided with four threaded mounting holes (6) and a weight reduction through hole (7).

4. The integrated cross-beam type six-dimensional force sensor elastomer according to claim 1, characterized in that, The strain concentration through hole (5) is a horizontal through hole penetrating both sides of the elastic sensitive beam (3), and / or a vertical through hole penetrating the upper and lower surfaces of the elastic sensitive beam (3).

5. The integrated cross-beam type six-dimensional force sensor elastomer according to claim 1, characterized in that, The strain concentration through hole (5) can be any one of a cylindrical hole, an elliptical cylindrical hole, or a waist-shaped cylindrical hole.

6. The integrated cross-beam type six-dimensional force sensor elastomer according to claim 1, characterized in that, Each of the elastic sensitive beams (3) has two sets of strain concentration through holes (5), one set of strain concentration through holes (5) is located at the inner end of the elastic sensitive beam (3), and the other set of strain concentration through holes (5) is located at the outer end of the elastic sensitive beam (3).

7. The integrated cross-beam type six-dimensional force sensor elastomer according to claim 1, characterized in that, The elastic sensitive beam (3) is a rectangular beam with a uniform cross-section, or a variable cross-section beam that is wide at both ends and narrow in the middle along the length direction.

8. An integrated cross-beam type six-dimensional force sensor elastomer according to any one of claims 1-7, characterized in that, The elastomer is integrally milled from aerospace aluminum alloy, stainless steel or titanium alloy.

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