A parking space detection device based on geomagnetic dynamic calibration

Abstract

The application discloses a parking space detection device based on geomagnetic dynamic calibration and concretely relates to the technical field of parking space detection, and comprises a civil foundation, a recess is formed in the top of the civil foundation, a panel is arranged in the recess, a circular hole is vertically arranged at the top of each corner of the panel, a screw groove cylinder is fixedly embedded at the position of the circular hole on the bottom surface of the inner cavity of the recess, a bolt is arranged in the circular hole, the bottom end of the bolt is screw-connected to the inner cavity of the corresponding screw groove cylinder, a buried box is fixedly connected to the center position of the bottom of the panel, a foundation pit is formed at the center position of the bottom surface of the inner cavity of the recess, the bottom end of the buried box is movably inserted into the inner cavity of the foundation pit on the civil foundation, and a downward pressing detection assembly is arranged at the top middle portion of the panel. The application can accurately detect whether a vehicle is parked on a parking space, can avoid the damage of a geomagnetic sensor caused by a vehicle during parking, and has high practical application value.

Description

Technical Field

[0001] This invention relates to the field of parking space detection technology, and more specifically, to a parking space detection device based on geomagnetic dynamic calibration. Background Technology

[0002] The emergence of large parking lots has solved the problem of urban parking difficulties, but it has also brought a series of problems, such as the difficulty of parking space management in large parking lots. In order to achieve real-time detection of parking spaces in large parking lots, that is, to detect whether a vehicle is parked in a certain parking space, various parking space detection technologies have been developed, and the technology of using geomagnetic signals to detect parking spaces is one of the most widely used technologies at present.

[0003] The detection principle of geomagnetic vehicle sensors is based on the fact that the ferromagnetic materials contained in the vehicle affect the geomagnetic signal in the area where the vehicle is located, causing the Earth's magnetic field lines in the area to bend. Once a vehicle passes near the sensor, the sensor can sensitively detect the change in signal, and through signal analysis, relevant information about the detected target can be obtained. Current geomagnetic vehicle detectors are typically embedded in the ground of parking spaces to detect whether a parking space is occupied.

[0004] However, because geomagnetic detection is very sensitive, any transient changes in the parking space can lead to misjudgments of the parking space status, such as temporary parking, passing vehicles nearby, or metal objects passing over the geomagnetic sensor. In addition, due to its insufficient load-bearing capacity, the geomagnetic sensor is easily damaged by being run over.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide a parking space detection device based on geomagnetic dynamic calibration. By pressing down a straight plate during the process of parking a vehicle in a parking space, the strip plate is driven to press down a flip plate, causing the other end of the flip plate to tilt upward and press against a touch switch, thus activating the geomagnetic sensor for detection. Furthermore, the straight plate does not come into contact with the geomagnetic sensor during the pressing process, thereby solving the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a parking space detection device based on geomagnetic dynamic calibration, comprising a civil engineering foundation, a groove being provided on the top of the civil engineering foundation, a plate being provided inside the groove, and a circular hole being vertically penetrating at each of the four corners of the top of the plate. A screw groove cylinder is fixedly embedded at the bottom end of the groove corresponding to the circular hole, and a bolt is inserted through the circular hole, with the bottom end of the bolt threaded into the corresponding screw groove cylinder. A buried box is fixedly connected to the center of the bottom of the plate, and a pit is provided at the center of the bottom end of the groove, with the bottom end of the buried box movably inserted into the pit on the civil engineering foundation. A pressure detection component is provided at the top center of the plate.

[0008] The pressure detection component includes grooves on the left and right sides of the top surface of the panel. A straight plate is provided at the position between the two grooves on the top of the panel. Springs are fixedly connected to the top surface of the panel at the four corners of the bottom surface of the straight plate. A slot is provided at the middle of both ends of the straight plate. Through holes are provided on both sides of the inner cavity of the slot. A trapezoidal plate is provided at the top of the panel at both ends of the straight plate and is slidably connected to the groove at the corresponding position. A second slot is provided at the middle of the end of the trapezoidal plate facing the straight plate. Through holes are provided on both sides of the inner cavity of the second slot. An inclined plate is provided between the two ends of the straight plate and the corresponding trapezoidal plate. Both ends of the inclined plate are movably inserted into the slots at the corresponding positions. A round rod is fixed at the position of the through holes at the front and rear sides of the inclined plate, corresponding to the positions of the through holes. The end of the round rod away from the inclined plate is movably inserted into the through holes at the corresponding positions. The center of the top of the panel is vertical. A through groove is provided, and a vertical groove runs through the center of the bottom end face of one of the grooves. A strip plate is movably inserted into the groove, with its top end fixedly connected to the bottom end face of a straight plate. A geomagnetic sensor is movably fitted inside the through groove. A spring three is fixedly connected to the bottom end face of the underground box cavity at the bottom edge of the geomagnetic sensor. A touch switch is installed at the center of the bottom end face of the geomagnetic sensor. A vertical plate is fixedly installed at the end of the bottom end face of the underground box cavity near the strip plate. A round rod two is fixedly installed on one side of the vertical plate. A flip plate is provided on the side of the vertical plate connected to the round rod two. One end of the flip plate extends to the bottom of the geomagnetic sensor, and the other end extends to the bottom of the strip plate. A through hole is provided through the flip plate at the position corresponding to the round rod two. The round rod two is rotatably connected to the inner circumference of the through hole through a bearing. A top block is fixedly installed at the top of the end of the flip plate extending to the bottom of the geomagnetic sensor. A spring two is fixedly connected between the end of the bottom end face of the flip plate near the top block and the bottom end face of the underground box cavity.

[0009] The beneficial effects of adopting the above-mentioned further solution are as follows: by pressing the straight plate downwards during the process of parking the vehicle into the parking space, the strip plate is driven to press down the flip plate, causing the other end of the flip plate to tilt upwards and press against the switch, thereby avoiding misjudgment of the parking space status caused by transient changes in the parking space. At the same time, the straight plate does not come into contact with the geomagnetic sensor during the process of being pressed down, which can prevent the geomagnetic sensor from being damaged by the vehicle during parking.

[0010] The geomagnetic sensor used is an optical fiber geomagnetic sensor, and a model is established to achieve self-calibration of the geomagnetic sensor.

[0011] I out =I1+I4=I i [f FBG +(1-f FBG ) 2 f FP ]

[0012] Among them, I out I1 represents the light intensity reflected at the center wavelength of the fiber Bragg grating, and I4 represents the light intensity after passing through the fiber Bragg grating. i f represents the light intensity when light emitted from a broadband light source reaches a fiber Bragg grating. FBG and f FP These are the reflectance coefficients of the fiber Bragg grating and the Fabry-Perot grating, respectively.

[0013]

[0014]

[0015] Where: f FBG and f FP Here, R represents the reflectance of the fiber Bragg grating and the Fabry-Perot grating, respectively; λ represents the general wavelength. B λ is the center wavelength; C is the reflection bandwidth; r is the reflectivity of the fiber end face; L is the Fabry-Perot cavity length; π is pi.

[0016] When an external magnetic field is applied to the sensor, the length of the Terfenol-D rod changes due to the magnetostrictive effect. The relationship between the strain of the Terfenol-D rod and the magnetic field is as follows:

[0017]

[0018] Where: ε T ΔL and L represent the strain, elongation, and original length of the Terfenol-D rod, respectively; C f is the magnetostriction coefficient, which is related to the external magnetic field and satisfies a linear relationship within a specific magnetic field range; H is the strength of the external magnetic field.

[0019] When the magnetic field and ambient temperature change, the EFPI reflection spectrum shifts due to magnetostriction and thermal effects. The amount of shift in the resonance interference spectrum caused by changes in magnetic field and temperature is...

[0020] Δλ m =λ m (α H ΔH+α T ΔT)

[0021] Where: λ m , Δλ m These represent the wavelength and wavelength shift corresponding to the m-th order interference valley, respectively; α H α T ΔH and ΔT are the sensitivity coefficients for magnetic field and temperature, respectively; ΔH and ΔT are the changes in magnetic field strength and temperature, respectively. Because fiber Bragg gratings are insensitive to magnetic fields, their center wavelength drift is only related to temperature and satisfies...

[0022] Δλ B =λ B βΔT

[0023] Where: λ B , Δλ B λ represents the center wavelength of the fiber Bragg grating and its variation, respectively; β is the temperature sensitivity coefficient of the fiber Bragg grating.

[0024] By establishing a self-calibration model for the geomagnetic sensor, self-calibration can be performed before use, ensuring the measurement accuracy of the geomagnetic sensor and providing a reliable component for the effective use of the parking space detection device of this invention. This self-calibration model is based on existing optical fiber theory, is easy to understand, and is highly operable, and can be promoted and used together with this invention.

[0025] In a preferred embodiment, the outer peripheral surface of the panel is fixedly covered with a sealing ring.

[0026] The beneficial effect of adopting the above-mentioned further solution is that it can prevent water from leaking from the connection between the panel and the groove to the bolt fixing position.

[0027] In a preferred embodiment, four springs are provided, and the four springs are arranged in a rectangular distribution. The end of the flip plate extending to the bottom of the geomagnetic sensor is located inside the rectangular cavity formed by the four springs.

[0028] The advantages of adopting the above-mentioned further solution are: on the one hand, it can support the geomagnetic sensor, and on the other hand, it can automatically reset the geomagnetic sensor after it has been lifted up.

[0029] In a preferred embodiment, guide blocks are fixedly provided at the middle of the front and rear sides of the two trapezoidal plates, and guide grooves are provided at the positions of the guide blocks on the front and rear sides of the groove cavity, and the guide blocks are slidably connected to the guide grooves at the corresponding positions.

[0030] The beneficial effect of adopting the above-mentioned further solution is that it can guide the trapezoidal block to move smoothly inside the groove.

[0031] In a preferred embodiment, the opposite sides of the two groove cavities are both inclined.

[0032] The advantage of adopting the above-mentioned further solution is that it facilitates the cleaning of debris accumulated inside the groove.

[0033] In a preferred embodiment, a sealing assembly is provided at the position of the geomagnetic sensor on the top of the panel. The sealing assembly includes a recessed groove at the center of the top surface of the panel. Square grooves are provided at the top of the left and right sides of the inner cavity of the recessed groove. A shaft is fixedly installed inside the two square grooves. Two sealing plates are provided inside the recessed groove between the two square grooves. Ear plates are fixedly connected to both ends of the opposite side of the two sealing plates. A through hole is provided through the ear plate at the position corresponding to the shaft. The shaft is movably inserted into the through hole at the corresponding position. A torsion spring is movably sleeved on the middle of the outer circumference of the shaft.

[0034] The beneficial effect of adopting the above-mentioned further solution is that it can protect the geomagnetic sensor when it is not parked, and prevent the dust accumulated on the surface of the parking space from forming a "shielding layer" on the top of the geomagnetic sensor, which would interfere with the detection of the geomagnetic sensor.

[0035] In a preferred embodiment, a limiting groove is provided at the top edge of one end of the two square grooves facing away from each other and at the top edge of one end of the two sealing plates facing away from each other. The two ends of the torsion spring are respectively movably embedded in the limiting groove at the corresponding position.

[0036] The advantage of adopting the above-mentioned further solution is that it can prevent the torsion spring from shifting during the flipping of the sealing plate.

[0037] In a preferred embodiment, a top ring is fixedly provided at the outer edge of the top surface of the geomagnetic sensor, and the upper end surface of the top ring is horizontally coplanar with the bottom end surface of the inner cavity of the square groove.

[0038] The advantage of adopting the above-mentioned further solution is that it can avoid damage caused by the geomagnetic sensor directly pressing and contacting the sealing plate during the ascent process.

[0039] In a preferred embodiment, a second through slot is provided at the position corresponding to the first through slot on the top of the straight plate.

[0040] The advantage of adopting the above-mentioned further scheme is that it enables geomagnetic sensors to detect changes in the Earth's magnetic field lines more quickly.

[0041] In a preferred embodiment, a sealing assembly is provided at each of the four corners of the top of the panel. The sealing assembly includes an annular groove formed on the top surface of the panel and concentrically arranged with the circular hole. A connecting strip is fixedly provided on one side of the top surface of the panel located in the annular groove. A circular block is fixedly connected to the end of the connecting strip away from the panel. A ring block adapted to the annular groove is fixedly provided on the side of the circular block facing the annular groove.

[0042] The beneficial effect of adopting the above-mentioned further solution is that it can protect the bolts fixing the panel to the civil engineering foundation, preventing the bolts from being corroded and making it inconvenient to disassemble later.

[0043] The technical effects and advantages of this invention are as follows:

[0044] 1. This invention, by pressing down the straight plate during the parking process, causes the strip plate to press down the flip plate, causing the other end of the flip plate to tilt upward and press against the touch switch, activating the geomagnetic sensor for detection. This can effectively avoid misjudgment of the parking space status caused by transient changes in the parking space due to temporary parking, passing vehicles, or metal objects passing over the geomagnetic sensor. At the same time, when the straight plate is pressed down to its maximum extent, its bottom surface and the top surface of the geomagnetic sensor are still separated, which can prevent the geomagnetic sensor from being damaged by the vehicle during parking.

[0045] 2. By setting up a sealing component, the two sealing plates will close under the restoring force of the torsion spring when no vehicle is parked in the parking space, so as to protect the geomagnetic sensor in the non-parking state and prevent dust accumulated on the surface of the parking space from forming a "shielding layer" on the top of the geomagnetic sensor, thereby interfering with the detection of the geomagnetic sensor.

[0046] 3. By establishing a self-calibration model for the geomagnetic sensor, the present invention can perform self-calibration before use, ensuring the measurement accuracy of the geomagnetic sensor and providing a reliable component for the effective use of the parking space detection device of the present invention. This self-calibration model is based on existing optical fiber theory, is easy to understand, and is highly operable, and can be promoted and used together with the present invention.

[0047] 4. By fully inserting the ring block into the ring groove and ensuring that the outer circumferential surface of the sealing ring, which is fixedly covered by the outer circumferential surface of the insert plate, is in a squeezing contact with the inner circumferential surface of the groove, the bolts fixing the insert plate and the civil engineering foundation can be protected, preventing the bolts from being corroded and making it difficult to disassemble later. Attached Figure Description

[0048] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the present invention. The embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0049] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0050] Figure 2 This is a partial structural diagram of the pressure detection component of the present invention.

[0051] Figure 3 This is a schematic diagram of the straight plate structure of the present invention.

[0052] Figure 4 This is a schematic diagram of the inclined plate structure of the present invention.

[0053] Figure 5 This is a schematic diagram of the trapezoidal plate structure of the present invention.

[0054] Figure 6 This is a schematic diagram of the flip plate structure of the present invention.

[0055] Figure 7 This is a schematic diagram of the panel structure of the present invention.

[0056] Figure 8 For the present invention Figure 2 Enlarged view of the middle section.

[0057] Figure 9 This is a schematic diagram of the sealing plate structure of the present invention.

[0058] Figure 10 For the present invention Figure 1 Enlarged view of section A in the middle.

[0059] The attached diagram is labeled as follows: 1. Civil foundation; 2. Groove; 3. Panel; 4. Pressure detection assembly; 41. Straight plate; 42. Inclined plate; 43. Trapezoidal plate; 44. Spring 1; 45. Groove; 46. Through groove 1; 47. Slot; 48. Strip plate; 49. Geomagnetic sensor; 410. Slot 1; 411. Through hole 1; 412. Slot 2; 413. Through hole 2; 414. Round rod 1; 415. Touch switch; 416. Vertical plate; 417. Round rod 2; 418. Flip plate; 419. Through hole; 420. Top block; 421. Spring 2; 422. Spring 3; 5. Sealing assembly; 51. Connecting strip; 52. Round block; 53. Ring block; 54. Ring groove. 6. Round hole, 7. Bolt, 8. Underground box, 9. Sealing assembly, 91. Sinking channel, 92. Square channel, 93. Shaft, 94. Sealing plate, 95. Ear plate, 96. Through hole three, 97. Torsion spring, 10. Guide groove, 11. Guide block, 12. Through groove two, 13. Top ring, 14. Restriction groove. Detailed Implementation

[0060] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art. The drawings are merely illustrative of this disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0061] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more exemplary embodiments. Numerous specific details are provided in the following description to give a full understanding of exemplary embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced with one or more of the specific details omitted, or other methods, components, steps, etc., can be employed. In other instances, well-known structures, methods, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this disclosure.

[0062] Example 1

[0063] Refer to the instruction manual appendix Figure 1-7 An embodiment of the present invention provides a parking space detection device based on geomagnetic dynamic calibration, comprising a civil engineering foundation 1, a groove 2 on the top of the civil engineering foundation 1, a plate 3 inside the groove 2, and a circular hole 6 vertically penetrating at each of the four corners of the top of the plate 3. A screw groove cylinder is fixedly embedded at the bottom end of the inner cavity of the groove 2 corresponding to the circular hole 6, and a bolt 7 passes through the circular hole 6, with the bottom end of the bolt 7 threadedly connected to the inside of the screw groove cylinder at the corresponding position, which can improve the stability of the connection between the bolt 7 and the civil engineering foundation 1. A buried box 8 is fixedly connected to the center of the bottom of the plate 3, and a pit is opened at the center of the bottom end of the inner cavity of the groove 2, with the bottom end of the buried box 8 movably inserted into the pit on the civil engineering foundation 1. A pressure detection component 4 is provided at the top center of the plate 3.

[0064] Furthermore, the pressure detection component 4 includes grooves 45 on the left and right sides of the top surface of the panel 3. A straight plate 41 is provided at the position between the two grooves 45 on the top of the panel 3. Springs 44 are fixedly provided at the four corners of the bottom surface of the straight plate 41 and are fixedly connected to the top surface of the panel 3. A slot 410 is provided at the middle of both ends of the straight plate 41. A through hole 411 is provided on both sides of the inner cavity of the slot 410. A trapezoidal plate 43 is provided at the top of the panel 3 at both ends of the straight plate 41 and is slidably connected to the inside of the corresponding groove 45. A slot 412 is provided at the middle of the end of the trapezoidal plate 43 facing the straight plate 41. Both sides of the inner cavity are provided with through holes 413. Inclined plates 42 are provided between the two ends of the straight plate 41 and the corresponding trapezoidal plates 43. Both ends of the inclined plates 42 are movably inserted into the corresponding slots 410 and 412. Round rods 414 are fixedly provided on the front and rear sides of the inclined plates 42 at positions corresponding to through holes 411 and 413. The end of the round rod 414 away from the inclined plate 42 is movably inserted into the corresponding through holes 411 and 413. A through groove 46 is vertically provided at the center of the top of the insert plate 3. A groove 47 is vertically provided in the middle of the bottom surface of one of the grooves 45. A strip plate 48, whose top end is fixedly connected to the bottom surface of the straight plate 41, is movably inserted into the groove 47. A geomagnetic sensor 49 is movably fitted inside the through groove 46. The bottom edge of the geomagnetic sensor 49 is fixedly positioned within the buried box 8. A spring 422 is fixedly connected to the bottom end face of the cavity. A touch switch 415 is installed at the center of the bottom end face of the geomagnetic sensor 49. A vertical plate 416 is fixedly provided at one end of the bottom end face of the underground box 8 near the strip plate 48. A round rod 417 is fixedly provided on one side of the vertical plate 416. A flip plate 418 is provided on the side of the vertical plate 416 connected to the round rod 417. One end of the flip plate 418 extends to the bottom of the geomagnetic sensor 49 and the other end extends to the bottom of the strip plate 48. A through hole 419 is provided through the flip plate 418 at the position corresponding to the round rod 417. The round rod 417 is rotatably connected to the inner circumferential surface of the through hole 419 through a bearing. A top block 420 is fixedly provided at the top of the end of the flip plate 418 extending to the bottom of the geomagnetic sensor 49. A spring 421 is fixedly connected between the bottom end face of the flip plate 418 near the top block 420 and the bottom end face of the underground box 8.

[0065] It should be noted that (1) before the top block 420 lifts the geomagnetic sensor 49 upward, the spring 421 is in a stretched state, so that the flip plate 418 is set in an inclined position; (2) the end of the strip plate 48 near the flip plate 418 and the end of the top block 420 away from the flip plate 418 are both set in an arc shape; (3) when the straight plate 41 is pressed down to the maximum extent, its bottom end face and the top end face of the geomagnetic sensor 49 are still separated; (4) the pressure detection component 4 is set in the middle of the parking space near the rear end.

[0066] During the parking process, when the vehicle is parked in the parking space, the wheel contacts the inclined plate 42 near the front of the parking space. Because the strip 48 at the bottom of the straight plate 41 passes through the groove 47 inside the corresponding groove 45, the inclined plate 42 at that position remains tilted. When the wheel moves along the inclined plate 42 to the position of the straight plate 41, it will directly press down on the straight plate 41 and compress the spring 44. During the pressing down of the straight plate 41, the inclined plates 42 at both ends of the straight plate 41 will change from tilted to horizontal, and push the trapezoidal block 43 to move along the corresponding groove 45. At the same time, it will drive the strip 48 to move down along the groove 47 and gradually press down on the flip plate 418. This causes the pressure end of the flip plate 418 to deflect downward about the circular rod 417 as the center axis, while the end connected to the top block 420 will deflect upward simultaneously. The geomagnetic sensor 49 is lifted upwards, and the spring 422 is stretched. When the top block 420 is tilted to a vertical position with the flip plate 418, it will contact and press the touch switch 415, thereby activating the geomagnetic sensor 49 for detection. At this time, the straight plate 41 is pressed down to its maximum extent. After the vehicle is completely parked in the parking space, the wheel near the rear end of the parking space is pressed on the corresponding inclined plate 42, thus keeping the straight plate 41 in a pressed state. Conversely, after the vehicle is completely removed from the parking space, the straight plate 41 will return to its original position under the restoring force of the spring 44. At the same time, the flip plate 418 will return to its original position under the restoring force of the spring 421. The top block 420 releases the pressure on the touch switch 415, turning off the geomagnetic sensor 49. The geomagnetic sensor 49 will also return to its original position under the restoring force of the spring 422.

[0067] In this embodiment, four springs 422 are provided, and the four springs 422 are arranged in a rectangular shape. The end of the flip plate 418 extending to the bottom of the geomagnetic sensor 49 is located inside the rectangular cavity formed by the four springs 422. On the one hand, it can support the geomagnetic sensor 49, and on the other hand, it can enable the geomagnetic sensor 49 to automatically reset after being lifted up, and can ensure that the force points of the geomagnetic sensor 49 are more uniform.

[0068] In this embodiment, guide blocks 11 are fixedly provided at the middle of the front and rear sides of the two trapezoidal plates 43. Guide grooves 10 are provided at the positions of the guide blocks 11 on the front and rear sides of the inner cavity of the groove 45. The guide blocks 11 are slidably connected to the inside of the guide grooves 10 at the corresponding positions. This can guide the trapezoidal blocks 43 to move smoothly inside the groove 45, preventing the trapezoidal blocks 43 from tilting up during the movement. This enables the debris inside the groove 45 in the initial state to move to the outside of the groove 45 at the corresponding position.

[0069] In this embodiment, the opposite sides of the inner cavities of the two grooves 45 are inclined, which facilitates the cleaning of debris accumulated inside the grooves 45 and reduces the residue of debris inside the grooves 45.

[0070] In this embodiment, a through slot 12 is provided at the top of the straight plate 41 corresponding to the position of through slot 1 46, so that the upper surface of the geomagnetic sensor 49 is not blocked, allowing the geomagnetic sensor 49 to detect changes in the Earth's magnetic field lines more quickly.

[0071] Example 2

[0072] Refer to the instruction manual appendix Figure 1-2 and Figure 7-9 According to an embodiment of the present invention, a parking space detection device based on geomagnetic dynamic calibration is provided with a sealing component 9 at the position of the geomagnetic sensor 49 on the top of the panel 3. The sealing component 9 includes a recess 91 opened at the center of the top surface of the panel 3. Square grooves 92 are opened at the top of the left and right sides of the inner cavity of the recess 91. A shaft 93 is fixedly installed inside the two square grooves 92. Two sealing plates 94 are provided inside the recess 91 between the two square grooves 92. Ear plates 95 are fixedly connected to the two ends of the opposite side of the two sealing plates 94. A through hole 96 is provided through the ear plate 95 at the position corresponding to the shaft 93. The shaft 93 is movably inserted into the through hole 96 at the corresponding position 95. A torsion spring 97 is movably sleeved on the middle of the outer peripheral surface of the shaft 93.

[0073] It should be noted that, in order not to affect the normal deflection of the sealing plate 94, both sealing plates 94 can be set as arc surfaces on opposite sides. During the process of parking a vehicle in the parking space, the upward-moving geomagnetic sensor 49 will push the two closed sealing plates 94 upward, causing the two sealing plates 49 to flip around the corresponding shaft 93 as the central axis, thereby exposing the geomagnetic sensor 49 and improving detection accuracy. Conversely, when no vehicle is parked in the parking space, the two sealing plates 94 will close under the restoring force of the torsion spring 97 to protect the geomagnetic sensor 49 in the non-parking state, preventing dust accumulated on the surface of the parking space from forming a "shielding layer" on the top of the geomagnetic sensor 49, which would interfere with the detection of the geomagnetic sensor 49.

[0074] In this embodiment, limiting grooves 14 are provided at the top edge of the opposite ends of the two square grooves 92 and at the top edge of the opposite ends of the two sealing plates 94. The two ends of the torsion spring 97 are respectively movably embedded in the limiting grooves 14 at the corresponding positions, which can center the compressive force on the torsion spring 97 and prevent the torsion spring 97 from shifting during the flipping of the sealing plate 94, thereby causing uneven force during the deflection of the sealing plate 94.

[0075] In this embodiment, a top ring 13 is fixedly provided at the outer edge of the top surface of the geomagnetic sensor 49. The upper end surface of the top ring 13 is horizontally coplanar with the bottom end surface of the inner cavity of the square groove 92. On the one hand, the fixed ring 13 can support the two sealing plates 94 in the closed state, and on the other hand, it can prevent the geomagnetic sensor 49 from being directly squeezed and contacted by the sealing plates 94 during the rising process, thus avoiding damage.

[0076] The geomagnetic sensor used is an optical fiber geomagnetic sensor, and a model is established to achieve self-calibration of the geomagnetic sensor.

[0077] I out =I1+I4=I i [f FBG +(1-f FBG ) 2 f FP ]

[0078] Among them, I out I1 represents the light intensity reflected at the center wavelength of the fiber Bragg grating, and I4 represents the light intensity after passing through the fiber Bragg grating. i f represents the light intensity when light emitted from a broadband light source reaches a fiber Bragg grating. FBG and f FP These are the reflectance coefficients of the fiber Bragg grating and the Fabry-Perot grating, respectively.

[0079]

[0080]

[0081] Where: f FBG and f FP Here, R represents the reflectance of the fiber Bragg grating and the Fabry-Perot grating, respectively; λ represents the general wavelength. B λ is the center wavelength; C is the reflection bandwidth; r is the reflectivity of the fiber end face; L is the Fabry-Perot cavity length; π is pi.

[0082] When an external magnetic field is applied to the sensor, the length of the Terfenol-D rod changes due to the magnetostrictive effect. The relationship between the strain of the Terfenol-D rod and the magnetic field is as follows:

[0083]

[0084] Where: ε T ΔL and L represent the strain, elongation, and original length of the Terfenol-D rod, respectively; C f is the magnetostriction coefficient, which is related to the external magnetic field and satisfies a linear relationship within a specific magnetic field range; H is the strength of the external magnetic field.

[0085] When the magnetic field and ambient temperature change, the EFPI reflection spectrum shifts due to magnetostriction and thermal effects. The amount of shift in the resonance interference spectrum caused by changes in magnetic field and temperature is...

[0086] Δλ m =λ m (α H ΔH+α T ΔT)

[0087] Where: λ m , Δλ m These represent the wavelength and wavelength shift corresponding to the m-th order interference valley, respectively; α H α T ΔH and ΔT are the sensitivity coefficients for magnetic field and temperature, respectively; ΔH and ΔT are the changes in magnetic field strength and temperature, respectively. Because fiber Bragg gratings are insensitive to magnetic fields, their center wavelength drift is only related to temperature and satisfies...

[0088] Δλ B =λ B βΔT

[0089] Where: λ B , Δλ B λ represents the center wavelength of the fiber Bragg grating and its variation, respectively; β is the temperature sensitivity coefficient of the fiber Bragg grating.

[0090] By establishing a self-calibration model for the geomagnetic sensor, self-calibration can be performed before use, ensuring the measurement accuracy of the geomagnetic sensor and providing a reliable component for the effective use of the parking space detection device of this invention. This self-calibration model is based on existing optical fiber theory, is easy to understand, and is highly operable, and can be promoted and used together with this invention.

[0091] Example 3

[0092] Refer to the instruction manual appendix Figure 1 and Figure 10 According to an embodiment of the present invention, a parking space detection device based on geomagnetic dynamic calibration is provided with sealing components 5 at the four corners of the top of the panel 3. The sealing components 5 include an annular groove 54 opened on the top surface of the panel 3 and arranged concentrically with the circular hole 6. A connecting strip 51 is fixedly provided on one side of the top surface of the panel 3 located in the annular groove 54. A circular block 52 is fixedly connected to the end of the connecting strip 51 away from the panel 3. A ring block 53 adapted to the annular groove 54 is fixedly provided on the side of the circular block 52 facing the annular groove 54.

[0093] Furthermore, a sealing ring is fixedly covered on the outer periphery of the panel 3, and the outer periphery of the sealing ring is in compression contact with the inner periphery of the groove 2.

[0094] It should be noted that the connecting strip 51, the round block 52, and the ring block 53 are all made of soft rubber material. After the insert plate 3 is fixedly installed in the groove 2 on the civil foundation 1 by the bolts 7, the ring block 53 is aligned with the corresponding position of the annular groove 54, and the round block 52 is pressed down to make the ring block 53 fully inserted into the annular groove 54. The outer circumference of the sealing ring fixed on the outer circumference of the insert plate 3 is in a compression contact with the inner circumference of the groove 2. This can protect the bolts 7 that fix the insert plate 3 to the civil foundation 1, and prevent the bolts 7 from being corroded, which would make it difficult to disassemble later.

[0095] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

[0096] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0097] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

[0098] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A parking space detection device based on geomagnetic dynamic calibration, comprising a civil engineering foundation (1), characterized in that: The top of the civil engineering foundation (1) is provided with a groove (2), and a plate (3) is provided inside the groove (2). The four corners of the top of the plate (3) are provided with vertically penetrating round holes (6). A screw groove cylinder is fixedly embedded at the bottom end of the inner cavity of the groove (2) corresponding to the round hole (6). A bolt (7) is inserted inside the round hole (6), and the bottom end of the bolt (7) is threaded to the inside of the screw groove cylinder at the corresponding position. A buried box (8) is fixedly connected to the center of the bottom of the plate (3). A foundation pit is provided at the center of the bottom end of the inner cavity of the groove (2), and the bottom end of the buried box (8) is movably inserted into the foundation pit on the civil engineering foundation (1). A pressure detection component (4) is provided at the top center of the plate (3). The pressure detection component (4) includes grooves (45) on the left and right sides of the top surface of the panel (3). A straight plate (41) is provided at the position between the two grooves (45) on the top of the panel (3). A spring (44) is fixedly provided at the four corners of the bottom surface of the straight plate (41) and is fixedly connected to the top surface of the panel (3). A slot (410) is provided at the middle of both ends of the straight plate (41). A through hole (411) is provided on both sides of the inner cavity of the slot (410). A trapezoidal plate (43) is provided at the top of the panel (3) at both ends of the straight plate (41) and is slidably connected to the inside of the corresponding groove (45). The trapezoidal plate (43) has a slot two (412) in the middle of one end facing the straight plate (41). Both sides of the inner cavity of the slot two (412) are provided with through holes two (413). An inclined plate (42) is provided between both ends of the straight plate (41) and the corresponding trapezoidal plate (43). Both ends of the inclined plate (42) are movably inserted into the slot one (410) and slot two (412) at the corresponding positions. A round rod one (414) is fixedly provided on both the front and rear sides of the inclined plate (42) at the positions corresponding to the through holes one (411) and through holes two (413). The end of the round rod one (414) away from the inclined plate (42) is movably inserted. The insert plate (3) is vertically connected to the corresponding perforation one (411) and perforation two (413). A through groove one (46) is vertically connected to the center of the top of the insert plate (3). A groove (47) is vertically connected to the center of the bottom end face of the inner cavity of one of the grooves (45). A strip plate (48) with its top end fixedly connected to the bottom end face of the straight plate (41) is movably inserted into the groove (47). A geomagnetic sensor (49) is movably fitted inside the through groove one (46). A spring three (422) is fixedly connected to the bottom end face of the inner cavity of the underground box (8) at the bottom edge of the geomagnetic sensor (49). The bottom end face of the geomagnetic sensor (49) A touch switch (415) is installed at the center. A vertical plate (416) is fixedly provided at one end of the bottom surface of the underground box (8) near the strip plate (48). A round rod (417) is fixedly provided on one side of the vertical plate (416). A flip plate (418) is provided on the side of the vertical plate (416) connected to the round rod (417). One end of the flip plate (418) extends to the bottom of the geomagnetic sensor (49) and the other end extends to the bottom of the strip plate (48). A through hole (419) is provided through the flip plate (418) at the position corresponding to the round rod (417). The round rod (417) is connected to the through hole (419) by a bearing. The inner circumferential surface of the flip plate (419) is rotatably connected. A top block (420) is fixedly provided at the top of one end of the flip plate (418) extending to the bottom of the geomagnetic sensor (49). A spring two (421) is fixedly connected between the bottom end of the flip plate (418) near the top block (420) and the bottom end of the inner cavity of the buried box (8). A sealing ring is fixedly covered on the outer circumferential surface of the insert plate (3). Four spring three (422) are provided, and the four spring three (422) are arranged in a rectangular shape. One end of the flip plate (418) extending to the bottom of the geomagnetic sensor (49) is located inside the rectangular cavity formed by the four spring three (422). Each of the top of the panel (3) is provided with a sealing component (9) corresponding to the position of the geomagnetic sensor (49). The sealing component (9) includes a recess (91) opened at the center of the top surface of the panel (3). The top of the left and right sides of the inner cavity of the recess (91) is provided with square grooves (92). A shaft (93) is fixedly installed inside the two square grooves (92). Two sealing plates (94) are provided inside the recess (91) between the two square grooves (92). Ear plates (95) are fixedly connected to both ends of the opposite side of the two sealing plates (94). A through hole (96) is provided through the ear plate (95) corresponding to the position of the shaft (93). The shaft (93) is movably inserted into the through hole (96) at the corresponding position 95. A torsion spring (97) is movably sleeved in the middle of the outer circumference of the shaft (93).

2. The parking space detection device based on geomagnetic dynamic calibration according to claim 1, characterized in that: Guide blocks (11) are fixedly provided in the middle of the front and rear sides of the two trapezoidal plates (43). Guide grooves (10) are provided in the front and rear sides of the groove (45) at the positions corresponding to the guide blocks (11), and the guide blocks (11) are slidably connected to the guide grooves (10) at the corresponding positions.

3. The parking space detection device based on geomagnetic dynamic calibration according to claim 2, characterized in that: The two grooves (45) are inclined on opposite sides of their inner cavities.

4. The parking space detection device based on geomagnetic dynamic calibration according to claim 1, characterized in that: A limiting groove (14) is provided at the top edge of the opposite end of the two square grooves (92) and at the top edge of the opposite end of the two sealing plates (94). The two ends of the torsion spring (97) are respectively movably embedded in the limiting groove (14) at the corresponding position.

5. A parking space detection device based on geomagnetic dynamic calibration according to claim 1, characterized in that: A top ring (13) is fixedly provided at the outer edge of the top surface of the geomagnetic sensor (49), and the upper surface of the top ring (13) is horizontally coplanar with the bottom surface of the inner cavity of the square groove (92).

6. The parking space detection device based on geomagnetic dynamic calibration according to claim 1, characterized in that: The top of the straight plate (41) is provided with a through slot two (12) at the position corresponding to the through slot one (46).

7. A parking space detection device based on geomagnetic dynamic calibration according to claim 1, characterized in that: Sealing components (5) are provided at the four corners of the top of the panel (3). The sealing components (5) include an annular groove (54) opened on the top surface of the panel (3) and arranged concentrically with the circular hole (6). A connecting strip (51) is fixedly provided on one side of the top surface of the panel (3) located in the annular groove (54). A circular block (52) is fixedly connected to one end of the connecting strip (51) away from the panel (3). A ring block (53) adapted to the annular groove (54) is fixedly provided on the side of the circular block (52) facing the annular groove (54).

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