Six-dimensional force-controlled touch probe and method of measurement

Abstract

The present application relates to the technical fields of six-dimensional force sensor, and particularly provides a six-dimensional force control contact type measuring sensor and a measuring method. The six-dimensional force control contact type measuring sensor comprises a body, a strain assembly arranged in the body, and a strain release assembly arranged between the body and the strain assembly. The strain assembly comprises a strain seat sliding up and down in the body. The strain assembly further comprises a strain piece fixed in a through hole of the strain seat. An elastic piece supports the strain seat in the cavity of the body, and forms a strain space between the strain seat and the cavity bottom of the body. The strain release assembly comprises an air cavity arranged on the strain seat, which significantly improves the precision stability and service life of the sensor under continuous operation. The sensor reduces the invasion of external pollutants, and is particularly suitable for high-cleanliness or high-humidity industrial scenes. The heat dissipation efficiency of the sensor is positively correlated with the measuring frequency, and the heat dissipation efficiency is automatically improved under high-frequency working conditions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of six-dimensional force sensors, in particular to a six-dimensional force control contact type measurement sensor and a measurement method. BACKGROUND

[0002] A six-dimensional force sensor, also known as a six-dimensional force and torque sensor or a six-axis force sensor, is an advanced sensor that can simultaneously measure three force components (Fx, Fy, Fz) and three torque components (Mx, My, Mz). It provides a function similar to human touch for robots, enabling robots to perceive and adapt to changes in the external environment, thereby completing more complex and delicate tasks. It is the core component of robot compliant control and operation. The core structure of the six-dimensional force sensor is usually composed of an elastic body, a strain gauge (or a piezoelectric crystal sensitive element), a circuit part and a signal processing unit. The strain gauge is contacted by three branch points on three sensitive points of the main shell, and after being stressed, it sends a six-dimensional force analysis to the sensitive element and obtains a sensitive signal.

[0003] However, the elastic body, strain gauge and circuit part are arranged in the main shell and are fully sealed, and the sensitive components work frequently in a multi-dimensional contact signal mode, which causes the sensitive elements to be difficult to release heat in a small sealed environment. High temperature environment can cause strain gauge temperature drift, resulting in signal distortion or even zero drift, affecting service life. SUMMARY

[0004] To solve the above problems, the present application provides a six-dimensional force control contact type measurement sensor, which comprises a body, a strain assembly arranged in the body, and a strain release assembly arranged between the body and the strain assembly. The strain assembly comprises a strain seat sliding up and down in the body, and the strain assembly further comprises a strain piece fixed in the through hole of the strain seat. The strain piece protrudes from the top of the body. The body is filled with an elastic piece which supports the strain seat in the cavity of the body. The strain space is formed between the strain seat and the cavity bottom of the body. The strain release assembly comprises an air cavity opened on the strain seat. The strain release assembly further comprises a first air duct opened on the cavity bottom of the body and corresponding to the air cavity. When the strain seat moves relative to the strain space and triggers the sensing end, the air cavity is pressed relative to the first air duct, and the hot air is discharged to the outside of the body through the first air duct.

[0005] As a further preferred, the top of the body is provided with a sealing cover, and a through hole is opened on the sealing cover. The top of the strain piece protrudes upward above the through hole.

[0006] As a further preferred, a plurality of connecting holes are arranged in the annular array between the body and the sealing cover. The connecting holes are arranged around the periphery of the trigger part.

[0007] As a further preferred embodiment, the bottom of the body has a ring array of several lower positioning holes, and the bottom surface of the strain element has a ring array of several upper positioning holes. The lower positioning holes correspond one-to-one with the bottom of the upper positioning holes. The elastic element includes a spring seat elastically supported between the upper positioning holes and the lower positioning holes at the same position. The spring seat includes a moving rod filled in the upper positioning hole and a guide seat filled in the lower positioning hole. The moving rod is inserted into the guide seat, and a spring is sleeved around the moving rod and the guide seat. One end of the spring abuts upward in the upper positioning hole, and the other end of the spring abuts downward in the lower positioning hole.

[0008] As a further preferred embodiment, the bottom periphery of the strain seat is provided with a chamfered surface, a first annular groove is formed on the chamfered surface, a second annular groove is formed on the bottom edge of the body, and the elastic element further includes an elastic plate filled between the first annular groove and the second annular groove.

[0009] As a further preferred embodiment, the chamfered surface is provided with a distance space from the cavity wall of the body, so that the elastic plate is in the shape of a trumpet with the opening facing downwards, and a trumpet cavity is formed between the elastic plate and the cavity bottom of the body.

[0010] As a further preferred embodiment, the strain relief assembly also includes a second air passage formed at the bottom of the body and corresponding vertically to the bottom horn cavity of the elastic plate. The other end of the second air passage is connected to the first air passage, and the first air passage gradually slopes downward toward the outer wall of the body.

[0011] The present invention also discloses a detection method, comprising the following steps:

[0012] S1. Connect the six-dimensional force-controlled contact measurement sensor to the equipment in the operating environment through the connection hole and rubber pad;

[0013] S2. When the bottom of the body is subjected to force, the rubber pad is compressed, and the strain gauge touches the equipment in the environment, causing the drive strain gauge to slide downward within the body, compressing the elastic element below, such as a spring or silicone body, and squeezing the air in the strain space. At this time, the displacement of the strain gauge triggers a measurement signal.

[0014] S3. The compressed air chamber causes the high-temperature airflow to be discharged at high speed through the downward-sloping first air passage;

[0015] S4. The chamfered surface pulls down the elastic plate, compressing and enlarging its horn cavity, increasing the air pressure and volume, so that the trapped hot air is forced into the first air passage through the second air passage. The second air passage and the first air passage form a multi-channel exhaust channel, improving exhaust efficiency, and at the same time completing signal detection.

[0016] The advantages of this invention compared to the prior art are:

[0017] A strain gauge is installed within the sensor body, sliding within it. Utilizing the strain gauge's mobility, a first air channel extends from the bottom of the body cavity to the outside. When the strain gauge is subjected to external force, each trigger signal from the sensor head forces the body to expel hot air, forming a passive heat dissipation mechanism synchronized with the measurement action. By linking the strain gauge's strain action with the air cavity and the first air channel to form a compressed air cooling structure, synchronous triggering of measurement and heat dissipation is achieved: each time the strain gauge contacts the measured object, its downward movement not only completes the mechanical signal acquisition but also simultaneously compresses the air cavity, expelling the high-temperature airflow through the first air channel. Upon resetting, it draws in external cold air, completely eliminating heat accumulation within the sealed cavity. This purely mechanical structure achieves zero-power heat dissipation, eliminating signal distortion caused by temperature drift and significantly improving the sensor's accuracy, stability, and lifespan under continuous operation. Simultaneously, it maintains a fully sealed state, reducing the intrusion of external contaminants, making it particularly suitable for high-cleanliness or high-humidity industrial environments. Its heat dissipation efficiency is positively correlated with the measurement frequency; under high-frequency conditions, heat dissipation efficiency automatically increases, forming an adaptive thermal management closed loop. Attached Figure Description

[0018] Figure 1 A schematic diagram of the external structure of a six-dimensional force-controlled contact measurement sensor provided for an embodiment of the present invention;

[0019] Figure 2 A top-view planar structural diagram of a six-dimensional force-controlled contact measurement sensor provided for an embodiment of the present invention;

[0020] Figure 3 A six-dimensional force-controlled contact measurement sensor provided for embodiments of the present invention comprises... Figure 2 A schematic diagram of the front view after sectioning A.

[0021] Figure 4 A schematic diagram of a six-dimensional force-controlled contact measurement sensor with the sealing cover and trigger part removed, provided for an embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of a disassembled six-dimensional force-controlled contact measurement sensor provided for an embodiment of the present invention.

[0023] In the figure: 10, body; 110, sealing cover; 20, strain assembly; 210, strain seat; 2102, first annular groove; 2103, chamfered surface; 2104, elastic plate; 2105, distance space; 111, through hole; 112, lower positioning hole; 113, second annular groove; 220, strain element; 2202, upper positioning hole; 230, strain space; 30, strain release assembly; 310, air cavity; 320, first air passage; 330, second air passage; 40, spring seat; 410, moving rod; 420, guide seat; 430, spring. Detailed Implementation

[0024] The above and other embodiments and advantages of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0025] In one implementation, such as Figures 1-5 As shown:

[0026] This embodiment provides a six-dimensional force-controlled contact measurement sensor, including a body 10, a strain component 20 disposed within the body 10, and a strain release component 30 disposed between the body 10 and the strain component 20. The strain component 20 includes a strain seat 210 that slides vertically within the body 10. It should be noted that the strain seat 210 is existing technology, and it typically has at least three support points on its circumference, each with a strain gauge. The outer ends of these three strain gauges contact the cavity wall of the body to trigger a signal. A strain circuit board is also disposed on the strain seat 210, and the circuit board and strain gauges constitute a six-dimensional force-sensitive signal (existing technology will not be elaborated upon). The present invention proposes that the strain component 20 further includes… A strain element 220 is fixed in the through hole 111 of the strain seat 210. The strain element 220 protrudes from the top of the body 10. An elastic element is filled inside the body 10. The elastic element supports the strain seat 210 on the upper part of the inner cavity of the body 10, and forms a strain space 230 between the strain seat 210 and the bottom of the cavity of the body 10. The strain release assembly 30 includes an air cavity 310 opened on the strain seat 210. The strain release assembly 30 also includes a first air channel 320 opened at the bottom of the cavity of the body 10 and corresponding vertically with the air cavity 310. When the strain seat 210 is strained relative to the strain space 230 and triggers the sensing end, the air cavity 310 is also compressed relative to the first air channel 320, so that the hot air is discharged to the outside of the body 10 through the first air channel 320.

[0027] When the bottom of the body 10 is subjected to force, the strain element 220 connected to the environment will touch the assembled environmental equipment, thereby causing the drive strain seat 210 to slide downward in the body 10, compressing the elastic element below such as a spring or silicone body and squeezing the air in the strain space 230. At this time, the displacement of the strain element 220 triggers the measurement signal; the synchronous linkage achieves the following technical effect: the downward movement of the strain seat 210 causes the air cavity 310 at its bottom to form a piston-type compressed air structure with the first air passage 320 at the bottom of the body cavity - the volume of the air cavity 310 is reduced, thereby forcing the high temperature gas emitted by the strain circuit board to be discharged outside the body 10 through the through first air passage 320. For example, each time a part is picked up on the robot assembly line, and the part provides a reaction force to the bottom of the body 10, the strain gauge 210 contacts the robot's connector and instantly transmits the reaction force to the strain gauge of the strain gauge 210, thus completing the acquisition of the force signal. At the same time, as the strain gauge 210 moves towards the bottom of the cavity of the body 10, the compression action of the air cavity 310 also discharges the hot air accumulated in the cavity of the body 10 during the previous measurement. When the external force is removed, the elastic element automatically pushes the strain gauge 210 back to its original position, and the volume of the air cavity 310 increases to draw in low-temperature air from the outside, realizing internal airflow circulation. Each contact measurement forces a hot air discharge and cold air replacement, forming a passive heat dissipation mechanism synchronized with the measurement action. By forming a related compressed air cooling structure with the strain gauge 210, the air chamber 310, and the first air channel 320, the measurement and heat dissipation are synchronously triggered: each time the strain gauge 210 contacts the object being measured, it moves down to not only complete the mechanical signal acquisition, but also simultaneously compresses the air chamber 310 so that the high-temperature airflow inside it is discharged from the body 10 through the first air channel 320, and draws in external cold air when resetting, completely eliminating the heat accumulation in the sealed cavity; this pure mechanical structure achieves zero-power heat dissipation, eliminates signal distortion caused by temperature drift, and significantly improves the accuracy, stability and service life of the sensor under continuous operation; at the same time, it maintains the fully sealed state of the body, reducing the intrusion of external contaminants, and is especially suitable for high-cleanliness or high-humidity industrial scenarios; its heat dissipation efficiency is positively correlated with the measurement frequency, and the heat dissipation efficiency automatically improves under high-frequency operating conditions, forming an adaptive thermal management closed loop.

[0028] like Figure 1 , Figure 3As shown, the top of the body 10 is provided with a sealing cover 110, and a through hole 111 is opened on the sealing cover 110. The top of the strain element 220 protrudes upward above the through hole 111. The sealing cover 110 ensures that the interior of the body 10 is basically closed. When the object being measured comes into contact with the bottom of the body 10, the strain element 220 protruding from the through hole 111 presses against the detection head. The strain element 220 senses the reaction force and transmits the reaction force to the strain seat 210. The strain seat 210 transmits the force to the strain gauge (existing technology) to obtain a signal. When the strain seat 210 is compressed and descends, the elastic element is compressed and shortened. At the same time, the hot air inside the body 10 is discharged to the outside of the body 10 through the first air passage 320. The hot air discharge and signal sensing are combined to achieve the purpose of releasing heat while triggering the signal.

[0029] like Figures 3 to 5 As shown, the bottom of the body 10 has a ring array of several lower positioning holes 112, and the bottom surface of the strain element 220 has a ring array of several upper positioning holes 2202. The lower positioning holes 112 correspond one-to-one with the bottom of the upper positioning holes 2202. The elastic element includes a spring seat 40 elastically supported between the upper positioning holes 2202 and the lower positioning holes 112 at the same position. The spring seat 40 includes a moving rod 410 filled in the upper positioning hole 2202 and a guide seat 420 filled in the lower positioning hole 112. The moving rod 410 is inserted into the guide seat 420, and the moving rod 410 and the guide seat 420 are aligned. A spring 430 is sleeved around the outer periphery of the seat 420. One end of the spring 430 is held upward against the upper positioning hole 2202, and the other end of the spring 430 is held downward against the lower positioning hole 112. The moving rod 410 and the guide seat 420 form a miniature piston relationship. When the strain seat 210 descends, it pushes the moving rod 410 down along the guide seat 420, which improves the stability of the strain seat 210 and compresses the spring 430, making it shorter. When the triggering force on the strain seat 210 disappears, the spring 430 returns to its length and pushes the moving rod 410 upward to reset. The moving rod 410 then pushes the strain seat 210 to reset.

[0030] like Figures 3 to 5As shown, the bottom periphery of the strain relief seat 210 is provided with a chamfered surface 2103, and a first annular groove 2102 is provided on the chamfered surface 2103. A second annular groove 113 is provided on the bottom edge of the body 10. The elastic element also includes an elastic plate 2104 filled between the first annular groove 2102 and the second annular groove 113. The chamfered surface 2103 is provided with a distance space 2105 from the cavity wall of the body 10, so that the elastic plate 2104 is in the shape of a trumpet with its opening facing downward, and a trumpet cavity is formed between the elastic plate 2104 and the cavity bottom of the body 10. The strain release assembly 30 also includes a second air passage 330 provided on the cavity bottom of the body 10 and corresponding to the bottom trumpet cavity of the elastic plate 2104. The other end of the second air passage 330 is connected to the first air passage 320, and the first air passage 320 gradually slopes downward toward the outer wall of the body 10.

[0031] The strain relief assembly 30 also includes a second air passage 330 located at the bottom of the cavity of the body 10 and corresponding vertically to the bottom horn cavity of the elastic plate 2104. The other end of the second air passage 330 is connected to the first air passage 320, and the first air passage 320 gradually slopes downward toward the outer wall of the body 10.

[0032] When the object being tested comes into contact with the strain gauge 220 protruding from the through hole 111, the strain gauge seat 210 is driven by downward pressure to displace the chamfered surface 2103 at its bottom downwards. The downward movement of the strain gauge seat 210 compresses the air chamber 310, forcing the hot air inside the body 10 to be discharged synchronously through the first air passage 320. At the same time, the chamfered surface 2103 presses down on the elastic plate 2104, causing it to continue to deform and enlarge in a trumpet shape, while approaching the first air passage 320. That is, by utilizing the increased volume of the trumpet cavity, the hot air inside the cavity is discharged into the second air passage 330 in a short time. With the connection between the second air passage 330 and the first air passage 320, the speed of hot air discharge is increased. The combination of the first air passage 320 and the second air passage 330 forms a multi-channel exhaust channel, improving exhaust efficiency and utilizing gravity. The rapid outward emission of hot gas, driven by the elastic plate 2104, incorporates heat from the bottom edge—areas inaccessible to traditional sensors—into the circulation system, improving cooling efficiency in dead zones by 200%. The design and horn-shaped configuration of the elastic plate 2104 allow it to recover its shape and move upwards during negative feedback, simultaneously assisting the spring seat 40 in its upward reset. The reverse force exerted on the strain gauge 210 during its shape recovery, combined with the force exerted by the spring seat 40 pushing the strain gauge 210 in reverse reset, doubles the reset capability of the strain gauge 210. Furthermore, the compression deformation of the elastic plate 2104 provides pressure to the second air passage 330, further enhancing hot gas emission efficiency.

[0033] The present invention also discloses a detection method, comprising the following steps:

[0034] S1. Connect the six-dimensional force-controlled contact measurement sensor to the equipment in the operating environment via the connection hole 50 and the rubber pad;

[0035] S2. When the bottom of the body 10 is subjected to force, the rubber pad is compressed, and the strain element 220 touches the equipment in the environment, thereby causing the drive strain seat 210 to slide downward within the body 10, compressing the elastic element below, such as a spring or silicone body, and squeezing the air in the strain space 230. At this time, the displacement of the strain element 220 triggers a measurement signal.

[0036] S3. The compressed air chamber 310 causes the high-temperature airflow to be discharged at high speed through the downwardly inclined first air passage 320;

[0037] S4. The chamfered surface 2103 pulls down the elastic plate 2104, which compresses and enlarges the horn cavity, increasing the air pressure and volume, so as to force the trapped hot air into the first air passage 320 through the second air passage 330. The second air passage 330 and the first air passage 320 form a multi-channel exhaust channel, improving exhaust efficiency and simultaneously completing signal detection.

[0038] The above orientation references do not represent the specific orientations of each component in this implementation scheme. This implementation scheme is only for the convenience of describing the scheme and to make relative descriptions based on the orientations of the references. In reality, the specific orientations of each component are based on their actual installation and use, as well as the orientation descriptions that are customary to those skilled in the art. This is hereby stated.

[0039] The specific embodiments described above further illustrate the inventive purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, or improvements made by those skilled in the art within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A six-dimensional force-controlled contact measurement sensor, characterized in that, The system includes a body (10), a strain assembly (20) disposed within the body (10), and a strain release assembly (30) disposed between the body (10) and the strain assembly (20). The strain assembly (20) includes a strain seat (210) that slides up and down within the body (10). The strain assembly (20) also includes a strain element (220) fixed within a through hole (111) of the strain seat (210). The strain element (220) protrudes from the top of the body (10). An elastic element is filled within the body (10), which supports the strain seat (210) against the upper part of the inner cavity of the body (10). This creates a strain space (230) between the strain seat (210) and the bottom of the cavity of the body (10). The strain release assembly (30) includes an air cavity (310) opened on the strain seat (210) and a first air channel (320) opened at the bottom of the cavity of the body (10) and corresponding vertically to the air cavity (310). When the strain seat (210) strains relative to the strain space (230) and triggers the sensing end, it also compresses the air cavity (310) relative to the first air channel (320), allowing hot air to be discharged outside the body (10) through the first air channel (320). The top of the body (10) is provided with a sealing cap (110), and a through hole (111) is provided on the sealing cap (110). The top of the strain element (220) protrudes upward above the through hole (111). Multiple connection holes (50) are arranged in a ring array between the body (10) and the sealing cover (110), and the connection holes (50) surround the periphery of the trigger part (2201). The cavity bottom of the body (10) has a ring array of several lower positioning holes (112), and the bottom surface of the strain element (220) has a ring array of several upper positioning holes (2202). The lower positioning holes (112) correspond one-to-one with the bottom of the upper positioning holes (2202). The elastic element includes a spring seat (40) elastically supported between the upper positioning holes (2202) and the lower positioning holes (112) at the same position. The spring seat (40) includes a moving rod (410) filled in the upper positioning hole (2202) and a guide seat (420) filled in the lower positioning hole (112). The moving rod (410) is inserted into the guide seat (420), and a spring (430) is sleeved around the moving rod (410) and the guide seat (420). One end of the spring (430) abuts upward in the upper positioning hole (2202), and the other end of the spring (430) abuts downward in the lower positioning hole (112). The strain gauge (210) has a chamfered surface (2103) on its bottom periphery. A first annular groove (2102) is provided on the chamfered surface (2103). A second annular groove (113) is provided on the bottom edge of the body (10). The elastic element also includes an elastic plate (2104) filled between the first annular groove (2102) and the second annular groove (113). The chamfered surface (2103) is provided with a distance space (2105) from the cavity wall of the body (10), so that the elastic plate (2104) is in the shape of a trumpet with its opening facing downwards, and a trumpet cavity is formed between the elastic plate (2104) and the cavity bottom of the body (10).

2. A six-dimensional force-controlled contact measurement sensor according to claim 1, characterized in that, The strain relief assembly (30) also includes a second air passage (330) formed at the bottom of the body (10) and corresponding to the bottom horn cavity of the elastic plate (2104). The other end of the second air passage (330) is connected to the first air passage (320), and the first air passage (320) gradually slopes downward toward the outer wall of the body (10).

3. A detection method, employing the six-dimensional force-controlled contact measurement sensor as described in claim 2, characterized in that, Includes the following steps: S1. Connect the six-dimensional force-controlled contact measurement sensor to the equipment in the operating environment through the connection hole (50) and the rubber pad; S2. When the bottom of the body (10) is subjected to force, the rubber pad is compressed, and the strain element 220 touches the equipment in the environment, thereby causing the drive strain seat (210) to slide downward in the body (10), compressing the elastic element below such as a spring or silicone body and squeezing the air in the strain space (230). At this time, the displacement of the strain element (220) triggers the measurement signal: S3. The compressed air chamber (310) causes the high-temperature airflow to be discharged at high speed through the downwardly inclined first air passage (320); S4. The chamfered surface (2103) presses down on the elastic plate (2104) to compress and enlarge its horn cavity, thereby increasing the air pressure and volume. This allows the trapped hot air to be forced into the first air passage (320) through the second air passage (330). The second air passage (330) and the first air passage (320) together form a multi-channel exhaust passage, improving exhaust efficiency and simultaneously completing signal detection.

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