A screw-on sensor and measurement method

Abstract

This invention discloses a screw-on sensor and its measurement method, relating to the field of sensor technology. The screw cap of the screw-on sensor is connected to a take-up reel via arc-shaped end-face teeth, enabling unidirectional transmission by winding the rope into the reel. The screw cap and an elastic body are connected via triangular end-face teeth to form unidirectional transmission. A V-shaped resistance strain gauge is provided on the outer surface of the elastic body to receive torque changes caused by its deformation. A power supply module and a signal acquisition and processing module within the base are connected to the V-shaped resistance strain gauge to form a full-bridge circuit, converting the resistance change of the strain gauge into a bridge strain voltage for output. An inertial measurement unit is also provided within the base for measuring angles and accelerations. This screw-on sensor can be applied to motion recognition, gait detection, and other fields. By being installed on shoelaces, it can provide reliable information for human motion measurement and, compared to commercially available shoelace screws, has a compact structure and a long service life.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, specifically to a rotary sensor and a measurement method thereof. Background Technology

[0002] IMU-based wearable motion sensors have been widely used in the field of human motion measurement. Compared with traditional marker-based motion capture systems, wearable motion sensors have significant advantages in terms of cost and portability.

[0003] The challenge of wearable motion sensors lies in achieving a reliable connection with the human body and selecting the appropriate connection point. Sensors on common wrist-worn devices tend to shift with body movement, and wrist movements don't accurately reflect full-body motion. Therefore, mounting the sensor to a shoe provides a more secure connection, allowing the sensor to directly participate in lower limb or full-body movements and more accurately measure motion.

[0004] Commonly integrated sensors in footwear include pressure sensors for measuring plantar pressure and inertial sensors for motion detection. Both require modifications to the shoe's construction to integrate the sensors, necessitating the involvement of shoe manufacturers. Furthermore, altering the shoe's construction can reduce its performance. Additionally, the high dynamic load on the sensors during human activity can shorten their lifespan.

[0005] Therefore, there is a need to design an intelligent screw-on sensor that can be fixed to the shoe upper by shoelaces for motion sensing to replace the pressure sensor on the sole of the foot. The screw-on sensor measures changes in shoelace tension and combines this with data collected by the IMU unit to reflect human movement. Summary of the Invention

[0006] The purpose of this invention is to provide a screw-on sensor and measurement method to solve the problems of unreliable connection between wearable sensors and the human body in the prior art, which cannot reflect the whole body movement of the human body well, as well as the problems of pressure sensors and inertial sensors integrated into footwear requiring changes to the shoe structure and low sensor durability, and the tension detection problem of rope-driven robots.

[0007] To achieve the above objectives, the specific technical solution adopted by the present invention is as follows:

[0008] In a first aspect, the present invention provides a screw-on sensor, comprising a screw cap, a protective housing, an elastomer, a take-up reel, a base, and a mounting seat.

[0009] The lower surface of the cap has a first annular groove along its edge, a tension spring fixing hole at its center, and a first end face tooth around the periphery of the tension spring fixing hole. A second end face tooth is provided along the inner circumference of the first annular groove.

[0010] The upper surface edge of the base is provided with a second annular groove, and the center of the upper surface is provided with a tension spring buckle.

[0011] The upper surface of the protective shell is inserted into the first annular groove and connected to the screw cap, while the lower surface is inserted into the second annular groove and connected to the base. The mounting base is provided with external threads, and the bottom of the base is connected to the mounting base through external threads. The mounting base is also provided with rope mounting holes.

[0012] The protective housing contains an elastomer, a take-up reel, and a tension spring. The elastomer's upper end face teeth mesh with a second end face tooth, enabling unidirectional transmission between the elastomer and the cap. The lower surface of the elastomer has a first and a second latch, which match grooves on the upper surface of the base, securing the elastomer and the base together.

[0013] The take-up reel engages with the first end face teeth via teeth on its upper end face, enabling unidirectional transmission between the take-up reel and the screw cap. The bottom of the take-up reel has an upper rope fixing hole, and a rope for connecting the shoe upper to the screw-on sensor is wound around the side plate of the take-up reel.

[0014] The upper part of the tension spring is connected to the tension spring fixing hole, the tension spring passes through the internal cavity of the take-up reel, and the lower part of the tension spring is connected to the tension spring buckle to ensure that it does not separate from the elastomer and the take-up reel when the rotating cap tightens the rope.

[0015] The outer surface of the elastomer is provided with V-shaped resistance strain gauges for measuring changes in torque applied to the elastomer. Each V-shaped resistance strain gauge consists of two strain gauges forming a 45° angle with the vertical axis. The bottom of the elastomer has two raised rope through holes that match the grooves on the edge of the base's upper surface. One end of the rope passes through the rope mounting hole and then through one rope through hole. The rope wraps several times around the side wall of the take-up reel before passing through two rope fixing holes, and then sequentially through another rope through hole and the rope mounting hole. The two ends of the rope exiting the rope mounting hole pass through the shoelace area, connecting the knob-type sensor to the shoe upper.

[0016] The base houses an inertial measurement unit, a power supply module, and a signal acquisition and processing module. Power and data lines from the power supply and signal acquisition and processing modules pass sequentially through a second wiring through-hole on the upper surface of the base and a first wiring through-hole on the sidewall of the elastic body, connecting to a V-shaped resistance strain gauge on the elastic body to form a full-bridge circuit. This circuit converts the resistance change of the strain gauge into a bridge strain voltage for output. The inertial measurement unit, connected between the power supply and signal acquisition and processing modules, measures acceleration and angle and transmits the data to the signal acquisition and processing module.

[0017] Preferably, the first end face tooth is an arc-shaped end face tooth, and the second end face tooth is a triangular end face tooth.

[0018] Preferably, the upper surface of the teeth on the end face of the elastomer has a smooth transition, which makes the unidirectional transmission between the elastomer and the screw cap less strenuous.

[0019] Preferably, the bottom surface of the aforementioned fitting seat is a curved surface that fits the upper of the shoe.

[0020] Preferably, the rope is a shoelace.

[0021] Preferably, the power supply module is powered by a lithium battery.

[0022] Preferably, the wall thickness at the location where the V-shaped resistance strain gauge is located on the sidewall of the elastomer is thinner than at other locations, in order to improve the sensitivity of the V-shaped resistance strain gauge.

[0023] Preferably, the number of the above-mentioned V-shaped resistance strain gauges is 2 sets.

[0024] Preferably, the bridge strain voltage U output by the above full-bridge circuit T The calculation method is as follows:

[0025]

[0026] Where k is the strain gauge sensitivity coefficient; R is the strain gauge resistance; U0 is the bridge power supply voltage; ε T The strain of each strain gauge caused by the torque T is calculated using the following formula:

[0027]

[0028] Where γ is the shear strain caused by torque T; ε 45° ω represents the normal strain along the 45° direction; G is the shear modulus of elastic body (4); t The torsional section modulus of the thin-walled section of the elastic body (4) is obtained by the following formula:

[0029]

[0030] Where D is the outer diameter of the thin-walled section of the elastomer, and α is the ratio of the inner diameter to the outer diameter.

[0031] ω t With ε T Substituting the calculation formula into the bridge strain voltage U T The calculation formula yields the following relationship between the strain voltage and torque of the bridge:

[0032]

[0033] The strain voltage U of the bridge T The strain voltage U of the bridge circuit is proportional to the torque T, and can be calculated from the torque T. TThe range of variation.

[0034] Secondly, the present invention provides a measurement method using the rotary sensor described in the first aspect, the specific method of which is as follows:

[0035] When testing is required, rotate the cap to rotate the take-up reel, tighten the rope wrapped around the side wall of the take-up reel, and complete the installation of the snap-on sensor;

[0036] During exercise, the shape of the shoe changes with the pressure applied by the foot, thereby altering the tension of the ropes passing through the shoe upper. The tensioned ropes cause the elastic body to deform, which in turn causes the V-shaped resistance strain gauges on the elastic body to generate torque, resulting in a change in resistance. The bridge strain voltage in the full-bridge circuit composed of the V-shaped resistance strain gauges and the power supply module changes. The signal acquisition and processing module amplifies and filters the bridge strain voltage signal before acquiring it, and then processes it through a microcontroller before storing it in the data storage module. The inertial measurement unit measures the angles and accelerations during the motion and stores the data in the data storage module. The data from the data storage module is then transmitted to the host computer via a wireless transmission module.

[0037] Compared with the prior art, the present invention has the following advantages:

[0038] (1) The screw-on sensor provided by the present invention is fixed to the shoe upper. Compared with the common wrist-worn sensor, the sensor provided by the present invention can directly participate in the movement of the lower limbs or the whole body. By measuring the change of shoelace tension and combining it with the IMU inertial measurement unit to reflect the human body movement, it can more accurately measure the human body movement and improve the sensor measurement accuracy.

[0039] (2) The screw-on sensor provided by the present invention is installed in the shoelace area. Compared with the common pressure sensors and inertial sensors integrated into shoes to measure the pressure of the sole, the sensor provided by the present invention does not require modification of the shoe structure and does not reduce the performance of the shoe. The sensor is easy to install and is more durable and reliable.

[0040] (3) The screw-on sensor provided by the present invention also has a shoelace screw-on function. By twisting the screw cap to drive the winding wheel to rotate, the shoelaces can be loosened / tightened quickly. It is simple to use. Compared with shoelace screw-on devices on the market, the parts fit together tightly and have a long service life. Attached Figure Description

[0041] Figure 1 This is a diagram of the combination of the rotary sensor provided in this embodiment;

[0042] Figure 2 This is an exploded structural diagram of the screw-on sensor provided in this embodiment;

[0043] Figure 3This is a cross-sectional view of the screw-on sensor provided in this embodiment;

[0044] Figure 4 This is a schematic diagram of the screw cap structure provided in this embodiment;

[0045] Figure 5 This is a schematic diagram of the elastomer structure provided in this embodiment;

[0046] Figure 6 This is a schematic diagram of the base structure provided in this embodiment;

[0047] Figure 7 This is a schematic diagram of the V-shaped resistance strain gauge arrangement provided in this embodiment;

[0048] Figure 8 This is a schematic diagram of the full-bridge circuit provided in this embodiment;

[0049] Figure 9 This is a block diagram of the structure of each module of the rotary sensor provided in this embodiment;

[0050] The attached figures are labeled as follows: 1. Screw cap; 11. First end face tooth; 12. First annular groove; 13. Tension spring fixing hole; 14. Second end face tooth; 2. Tension spring; 3. Protective shell; 4. Elastomer; 41. Elastomer end face tooth; 42. Rope through hole; 43. First buckle; 44. Second buckle; 45. First cable routing through hole; 5. Take-up reel; 51. Take-up reel end face tooth; 52. Rope fixing hole; 6. Base; 61. Tension spring buckle; 62. Second annular groove; 63. Second cable routing through hole; 64. Groove; 7. Fitting seat; 71. External thread; 72. Rope mounting hole. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are only a preferred solution of the present invention applied to the human motion measurement scenario, and not all of them. Other embodiments obtained by those skilled in the art without creative effort are all within the scope of protection of the present invention.

[0052] In the description of this invention, it should be understood that the terms "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" and "second" may explicitly or implicitly include at least one of those features.

[0053] In the description of this invention, it should be understood that when an element is considered to be "connected" to another element, it can be a direct connection to the other element or an indirect connection, i.e., there is an intermediate element. Conversely, when an element is said to be "directly" connected to another element, there is no intermediate element.

[0054] like Figures 1-3 As shown, this embodiment provides a screw-on sensor for human motion measurement, including a screw cap 1, a protective shell 3, an elastomer 4, a take-up reel 5, a base 6 and a fitting seat 7, an inertial measurement unit, a power supply module, a signal acquisition and processing module, a data storage module and a wireless module.

[0055] Figure 4 This is a schematic diagram of the screw cap 1 provided in this embodiment. A first annular groove 12 is provided on the lower surface edge of the screw cap 1. A tension spring fixing hole 13 is provided at the center of the lower surface, and three arc-shaped end face teeth are provided around the periphery of the tension spring fixing hole 13. Between the arc-shaped end face teeth and the first annular groove, a plurality of triangular end face teeth 14 are provided along the inner periphery of the first annular groove 12. To save the transmission force between the meshing end face teeth, one side of the triangular end face teeth has a smooth transition.

[0056] Figure 5 This is a schematic diagram of the structure of the elastic body 4 provided in this embodiment. The upper surface of the elastic body is provided with elastic body end face teeth 41 that can mesh with the triangular end face teeth on the cap to form a one-way transmission, thereby enabling the cap 1 to have a one-way rotation and locking function. One side of the upper surface of the elastic body end face teeth 41 has a smooth transition, making the one-way transmission between the elastic body 4 and the cap 1 less strenuous and reducing the resistance when the cap 1 rotates. The lower surface of the elastic body is provided with a first latch 42 and a second latch 43 for fixed connection with the base. The bottom side of the elastic body is provided with two raised rope through holes 42 that match the grooves 64 on the edge of the upper surface of the base 6. In this embodiment, to improve the stability of rope fixing, the included angle between the two rope through holes 42 is 90°. However, it should be noted that, without departing from the spirit and scope of the present invention, the included angle between the two rope through holes 42 on the elastic body can be distributed between 90° and 180°.

[0057] Two sets of V-shaped resistance strain gauges are installed on the sidewall of the elastomer. The V-shaped resistance strain gauges and the elastomer together constitute a torque measurement sensor. Due to the deformation of the elastomer caused by the change in torque, strain is generated at the bonding points of the strain gauges, and the resistance value of the strain gauges changes after strain occurs. The function of the strain gauges is to convert the torque of the specimen into a relative change in resistance. However, because the resistance change of the resistance strain gauge is very small, it is not easy to measure directly. Therefore, a full-bridge circuit is usually used to connect the strain gauges, converting the resistance change into a voltage signal for output.

[0058] The sidewall of the elastomer is also provided with a first wiring through hole 45 for the power line and data line to pass through. In this embodiment, the wall thickness of the area on the elastomer for attaching the V-shaped resistance strain gauge is thinner than that of other areas, so as to reduce the torsional section modulus of the V-shaped resistance strain gauge attachment position, thereby increasing the sensitivity of torque measurement. At the same time, a cavity is formed between the thinned part and the protective shell 3, providing space for the attachment of the V-shaped resistance strain gauge.

[0059] Figure 6 This is a schematic diagram of the base 6 provided in this embodiment. A second annular groove 62 is provided on the edge of the upper surface of the base 6. The second annular groove 62 has two grooves 64 that match the rope through holes 42 on the elastic body 4. A tension spring buckle 61 is provided at the center of the upper surface of the base 6. A second cable routing through hole 63 is also provided on the upper surface for data cables and power cables to pass through.

[0060] To improve the fit between the screw-on sensor and the shoe upper, enhance the connection reliability, and improve wearing comfort, the lower surface of the fitting base 7 is designed to conform to the shoe upper, preferably a saddle surface. An external thread 71 is provided on the top of the fitting base 7, and the base 6 is fixedly connected to the fitting base 7 via the external thread 71. A rope mounting hole 72 is also provided on the fitting base 7. The rope can pass through the rope mounting hole 72, and its tension during movement provides a downward pressure to the fitting base 7, making the overall force on the screw-on sensor more stable and increasing the reliability of the connection.

[0061] The elastomer 4 is surrounded by a protective shell 3. The upper surface of the protective shell 3 is inserted into the first annular groove 12 and connected to the cap 1, while the lower surface is inserted into the second annular groove 62 and connected to the base 6. A take-up reel 5 is installed inside the elastomer 4. The take-up reel 5 has take-up end face teeth 51 on its upper surface that mesh with the three arc-shaped end face teeth on the cap 1, enabling unidirectional transmission between the take-up reel 5 and the cap 1. The bottom of the take-up reel 5 has an upper rope fixing hole 52, and a rope for connecting the shoe upper and the screw-on sensor is wound around its side plate. This allows the take-up reel 5 to tighten the rope as the cap 1 rotates.

[0062] The aforementioned cap 1 and base 6 are connected by a tension spring 2. The upper part of the tension spring 2 is connected to the tension spring fixing hole 13 on the lower surface of the cap 1, the tension spring 2 passes through the internal cavity of the take-up reel 5, and the lower part is connected to the tension spring buckle 61 on the upper surface of the base 6. The tension of the tension spring 2 ensures that the cap 1 does not separate from the elastic body 4 and the take-up reel 5 when the cap 1 is rotated to tighten the rope.

[0063] In this embodiment, the rope used is the shoelace. One end of the rope passes through the rope mounting hole 72 and then through a rope through hole 42. The rope is wound several times around the side wall of the take-up reel 5 and then passes through two rope fixing holes 52, and then sequentially through another rope through hole 42 and the rope mounting hole 72. The rope installation method here is similar to the way shoelaces are installed on the shoe upper. The two ends of the rope that pass out of the rope mounting hole 72 pass through the shoelace part of the shoe upper to be monitored, fixing the knob-type sensor to the shoe upper.

[0064] The base 6 houses an inertial measurement unit (IMU), a power supply module, a signal acquisition and processing module, a data storage module, and a wireless module. The power and data lines from the power supply and signal acquisition and processing modules pass sequentially through a second wiring through-hole 63 on the upper surface of the base 6 and a first wiring through-hole 45 on the side wall of the elastic body 4, connecting with two sets of V-shaped resistance strain gauges on the elastic body 4 to form a full-bridge circuit.

[0065] In this embodiment, the arrangement of the V-shaped resistance strain gauges is as follows: Figure 7 As shown, the schematic diagram of the full-bridge circuit is as follows: Figure 8 As shown. Since the torque generates circumferential shear strain on the elastic body, a V-shaped resistance strain gauge is selected and bonded along a 45° direction. Because the full-bridge circuit offers high measurement sensitivity, eliminates nonlinear errors, and has built-in temperature compensation, the strain gauges are arranged into a full-bridge circuit for measurement. The bridge strain voltage U is obtained using the following formula. T :

[0066]

[0067] Where k is the strain gauge sensitivity coefficient; R is the strain gauge resistance; U0 is the bridge power supply voltage; ε T The strain of each strain gauge caused by the torque T can be calculated using the following formula:

[0068]

[0069] Where γ is the shear strain caused by torque T; ε 45° ω represents the normal strain along the 45° direction; G is the shear modulus of elastic body 4; t The torsional section modulus at the thin-walled section of the elastic body 4 can be obtained by the following formula:

[0070]

[0071] Where D is the outer diameter of the thin-walled part of the elastomer 4, and α is the ratio of the inner diameter to the outer diameter.

[0072] ω t With ε T Substituting the calculation formula into the bridge strain voltage U TThe calculation formula yields the following relationship between the strain voltage and torque of the bridge:

[0073]

[0074] It can be known that the strain voltage U of the bridge is T The strain voltage U of the bridge circuit is proportional to the torque T, and can be calculated from the torque T. T The range of variation is determined, and the subsequent signal amplification and acquisition circuit is designed accordingly.

[0075] like Figure 9 The diagram shows the structural block diagram of each module. The elastic body and the strain gauges on it form a torque measurement sensor. The power supply module and the signal acquisition and processing module have their power and data lines passing sequentially through the second wiring through-hole 63 on the upper surface of the base 6 and the first wiring through-hole 45 on the side wall of the elastic body 4, connecting to the resistance strain gauges on the elastic body 4 to form a full-bridge circuit for measuring and collecting torque changes. The power supply module is responsible for supplying power to each module; in this embodiment, a lithium battery is selected as the power source for the power supply module.

[0076] The base 6 also houses an IMU (Inertial Measurement Unit), which is connected between the power supply module and the signal acquisition and processing module to measure angles and accelerations during motion.

[0077] Data collected by the torque measurement sensor and inertial measurement unit is amplified and filtered by the signal acquisition and processing module, then processed by the microcontroller's ADC before being stored in the data storage module. The data in the data storage module can be transmitted to a host computer via Bluetooth or other wireless communication methods after connecting to a wireless module. The host computer, combining the rope tension changes measured by strain gauges and the IMU unit data, can reliably measure human motion using appropriate algorithms. Furthermore, corresponding mobile software can be developed to communicate with the rotary sensor, receive and process data, and view results in real time.

[0078] This embodiment also provides a method for using the above-described rotary sensor, as follows:

[0079] When using this screw-on sensor, first according to Figures 1-5As shown, the rope is fixed to the rope fixing hole 52 on the take-up reel 5. The cap 1 is connected to the take-up reel end face tooth 51 on the take-up reel 5 via the first end face tooth 11. Rotating the cap 1 clockwise drives the take-up reel to rotate, tightening the rope. To loosen the rope, simply lift the cap 1 to separate the second end face tooth 14 from the elastic body end face tooth 41, and rotate the cap 1 counterclockwise. During movement, the shape of the shoe changes with the pressure applied by the foot, thereby changing the tension of the rope passing through the shoe upper; the tightened rope causes the elastic body 4 to deform, causing the V-shaped resistance strain gauge on the elastic body 4 to generate torque, and the resistance value changes; the bridge strain voltage in the full-bridge circuit composed of the V-shaped resistance strain gauge and the power supply module changes; the inertial measurement unit measures the angle and acceleration during the movement; the signal acquisition and processing module amplifies and filters the bridge strain voltage signal, as well as the angle and acceleration signals, and then processes them through the microcontroller and stores them in the data storage module; the data in the data storage module is sent to the host computer through the wireless transmission module. It can reliably measure human movement, extract time-frequency features, and combine them with algorithms such as deep learning, and can be applied to fields such as motion recognition and gait detection.

[0080] The embodiments described above are merely preferred solutions for applying the present invention to human motion measurement scenarios, and are not intended to limit the invention. Various changes and modifications can be made to the technical features described in the specific embodiments above without departing from the spirit and scope of the invention. For example, the distribution of rope through-holes on the elastomer can be changed from a 90° angle distribution to a 180° angle facing distribution, and moved to the middle part of the device to balance the forces and reduce rope deformation and wear; the IMU inertial measurement unit module can be removed, and the overall structure's volume and weight can be further optimized; the aforementioned screw-on sensor can be installed on a rope-driven robot for tension detection.

[0081] The screw-on sensor provided in this embodiment has a wide range of applications, including motion recognition and gait detection. By being installed on shoelaces, the measured changes in shoelace tension, combined with IMU unit data, can provide reliable information for human motion measurement. Compared to commercially available shoelace screw-ons, it has a more compact structure and a longer service life. This screw-on sensor can also be installed on rope-driven robots for tension detection. Compared to similar tension sensors, this sensor offers higher accuracy, smaller size, lighter weight, and minimal impact on the movement of the robot's end effector.

[0082] To avoid unnecessary repetition, this invention will not describe all possible variations separately. Therefore, any technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of this invention.

Claims

1. A rotary sensor, characterized in that, Includes a screw cap (1), a protective shell (3), an elastomer (4), a take-up reel (5), a base (6), and a fitting seat (7); The lower surface edge of the cap (1) is provided with a first annular groove (12), and the center of the lower surface is provided with a tension spring fixing hole (13). The periphery of the tension spring fixing hole (13) is provided with a first end face tooth (11); and the inner periphery of the first annular groove (12) is provided with a second end face tooth (14). The base (6) has a second annular groove (62) on the edge of its upper surface and a tension spring buckle (61) at the center of its upper surface. The upper surface of the protective shell (3) is inserted into the first annular groove (12) and connected to the screw cap (1), and the lower surface is inserted into the second annular groove (62) and connected to the base (6); the fitting seat (7) is provided with an external thread (71); the bottom of the base (6) is connected to the fitting seat (7) through the external thread (71); the fitting seat (7) is also provided with a rope mounting hole (72); The protective shell (3) is provided with an elastomer (4), a take-up reel (5) and a tension spring (2); the elastomer (4) is engaged with the second end face tooth (14) through the elastomer end face tooth (41) provided on the upper surface, so that the elastomer (4) and the screw cap (1) form a one-way transmission; the lower surface of the elastomer (4) is provided with a first buckle (43) and a second buckle (44), the first buckle (43) and the second buckle (44) match the groove on the upper surface of the base (6), so that the elastomer (4) and the base (6) are fixedly connected; The take-up reel (5) meshes with the first end face tooth (11) through the take-up reel end face tooth (51) provided above, so that the take-up reel (5) and the screw cap (1) form a one-way transmission; the bottom of the take-up reel (5) is provided with an upper rope fixing hole (52), and the side plate of the take-up reel (5) is wrapped with a rope for connecting the shoe upper and the screw-type sensor; The upper part of the tension spring (2) is connected to the tension spring fixing hole (13), the tension spring (2) passes through the internal cavity of the take-up reel (5), and the lower part of the tension spring (2) is connected to the tension spring buckle (61) to ensure that the rotating cap (1) does not separate from the elastic body (4) and the take-up reel (5) when tightening the rope; The outer surface of the elastic body (4) is provided with a V-shaped resistance strain gauge for measuring the torque change of the elastic body (4); the V-shaped resistance strain gauge is composed of two resistance strain gauges with an angle of 45° to the vertical axis; the bottom of the elastic body (4) is provided with two raised rope through holes (42) that match the grooves (64) on the edge of the upper surface of the base (6); one end of the rope passes through the rope mounting hole (72) and then through a rope through hole (42); the rope is wound around the side wall of the take-up reel (5) several times and then passes through two rope fixing holes (52), and then passes through another rope through hole (42) and rope mounting hole (72) in sequence; the two ends of the rope that pass out of the rope mounting hole (72) pass through the shoelace part and connect the buckle sensor to the shoe upper; The base (6) is equipped with an inertial measurement unit, a power supply module, and a signal acquisition and processing module. The power supply module and the signal acquisition and processing module have their power lines and data lines passing through the second wiring through hole (63) on the upper surface of the base (6) and the first wiring through hole (45) on the side wall of the elastic body (4) in sequence. They are connected to the V-shaped resistance strain gauge on the elastic body (4) to form a full-bridge circuit, which converts the resistance change of the strain gauge into the bridge strain voltage of the full-bridge circuit for output. The inertial measurement unit is connected between the power supply module and the signal acquisition and processing module and is used to measure acceleration and angle.

2. The rotary sensor according to claim 1, characterized in that, The first end face tooth (11) is an arc-shaped end face tooth; the second end face tooth (14) is a triangular end face tooth.

3. The rotary sensor according to claim 1, characterized in that, The upper surface of the teeth (41) of the elastomer end face is smoothly transitioned, making the unidirectional transmission between the elastomer (4) and the cap (1) less labor-intensive.

4. The rotary sensor according to claim 1, characterized in that, The bottom surface of the fitting seat (7) is a curved surface that fits the shoe upper.

5. The rotary sensor according to claim 1, characterized in that, The rope is a shoelace.

6. The rotary sensor according to claim 1, characterized in that, The power supply module is powered by a lithium battery.

7. The rotary sensor according to claim 1, characterized in that, The wall thickness of the elastic body (4) at the location where the V-shaped resistance strain gauge is provided is thinner than at other locations, so as to improve the sensitivity of the V-shaped resistance strain gauge.

8. The rotary sensor according to claim 1, characterized in that, The number of V-shaped resistance strain gauges is 2 sets.

9. The rotary sensor according to claim 1, characterized in that, The bridge strain voltage U output by the full-bridge circuit T The calculation method is as follows: ； Where k is the strain gauge sensitivity coefficient; R is the strain gauge resistance; U0 is the bridge power supply voltage; ε T The strain of each strain gauge caused by the torque T is calculated using the following formula: ； Where γ is the shear strain caused by torque T; ε 45° G is the normal strain along the 45° direction; G is the shear modulus of elastic body (4); ω t The torsional section modulus of the thin-walled section of the elastic body (4) is obtained by the following formula: ； Where D is the outer diameter of the thin wall of the elastic body (4), and α is the ratio of the inner diameter to the outer diameter; ω t With ε T Substituting the calculation formula into the bridge strain voltage U T The calculation formula yields the following relationship between the strain voltage and torque of the bridge: The strain voltage U of the bridge circuit T The strain voltage U of the bridge circuit is proportional to the torque T, and can be calculated from the torque T. T The range of variation.

10. A measurement method using the rotary sensor according to any one of claims 1 to 9, characterized in that, The specific method is as follows: When testing is required, rotate the cap (1) to drive the take-up reel (5) to rotate, tighten the rope wrapped around the side wall of the take-up reel (5), and complete the installation of the snap-on sensor; During exercise, the shape of the shoe changes with the pressure applied by the foot, thereby changing the tension of the rope passing through the shoe upper; the tensioned rope causes the elastic body (4) to deform, which in turn causes the V-shaped resistance strain gauge on the elastic body (4) to generate torque, and the resistance value changes. The strain voltage across the bridge circuit, composed of the V-shaped resistance strain gauge and the power supply module, changes. The signal acquisition and processing module amplifies and filters the strain voltage signal before acquiring it, then processes it using a microcontroller and stores it in the data storage module. The inertial measurement unit measures the angle and acceleration during the motion process and stores the data in the data storage module. The data from the data storage module is then transmitted to the host computer via a wireless transmission module.

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