A method and apparatus for monitoring the pressure inside a tire

Abstract

The application discloses a method for monitoring tire internal pressure, comprising the following steps: S1, covering PTFE film with thickness of 0.13 mm and width of 100 mm on the tire; S2, the pressure belt, five copper electrodes with width of 10 mm and thickness of 0.08 mm are equidistantly connected in parallel on the pressure belt, and a layer of 0.08 mm PTFE film with same width is pasted on the surface of the copper electrode; S3, driving the vehicle on the monitoring belt; S4, monitoring the tire pressure condition of the vehicle by using an electrometer, a collection card and a display. The application provides a method for monitoring vehicle tire pressure based on a friction nanometer generator; and some related contents for verifying the theory are provided in the specific embodiment. According to the experimental results, it can be determined that according to the different vehicle tire pressure, speed and load, the tire pressure monitoring system can obtain open circuit voltage signals with different amplitudes, so that the tire pressure state of the vehicle can be judged according to the amplitude of the open circuit voltage.

Description

Technical Field

[0001] This invention discloses a method and apparatus for monitoring the internal pressure of a tire, relating to the field of tire internal pressure monitoring technology. Background Technology

[0002] Tire pressure issues account for up to 46% of traffic accidents on highways. Tire pressure monitoring, ABS, and airbags are considered the three major safety systems in automobiles. As an active safety system, tire pressure monitoring systems must provide real-time, efficient, and accurate tire pressure information. Therefore, real-time, rapid, and effective detection of vehicle tire pressure is crucial for improving driving safety. Existing tire pressure monitoring systems have the following problems:

[0003] 1. Indirect tire pressure monitoring systems estimate tire pressure based on the resonant frequency of tire circumferential vibration, but they can only estimate the relative state of tire pressure, resulting in low accuracy and significant errors. With the development of computers, a machine learning-based indirect tire pressure monitoring method combining decision trees and Bayesian classifiers has been proposed. The effectiveness of the algorithm has been verified using wheel speed signals collected from real vehicles. Although it is low-cost and highly accurate, its accuracy is easily affected by road conditions and driving conditions, leading to potential erroneous judgments.

[0004] 2. The shortcomings of direct-measurement tire pressure monitoring systems (TPMS) are that they cannot adapt to harsh driving environments and are easily damaged, leading to inaccurate measurements. To ensure vehicle safety, my country has mandated the installation of TPMS in newly manufactured passenger vehicles since January 2020, which has increased automobile production costs, and its monitoring sensitivity is affected by operating conditions.

[0005] In summary, existing tire pressure monitoring systems suffer from insufficient accuracy.

[0006] Content of this invention

[0007] The purpose of this invention is to provide a method and apparatus for monitoring the internal pressure of a tire, thereby addressing the problem of insufficient accuracy in existing tire pressure monitoring systems.

[0008] To achieve the above-mentioned technical objectives and effects, the invention is implemented through the following technical solution:

[0009] A method for monitoring tire internal pressure includes the following steps:

[0010] S1. Cover the tire with a PTFE film with a thickness of 0.13mm and a width of 100mm;

[0011] S2, a pressure belt, wherein five copper electrodes, each 10 mm wide and 0.08 mm thick, are connected in parallel at equal intervals on the pressure belt, and a 0.08 mm wide PTFE film is attached to the surface of the copper electrodes.

[0012] S3. The vehicle is driven on the monitoring belt via the terminal;

[0013] S4. Monitor the vehicle's tire pressure using an electrometer, data acquisition card, and display.

[0014] Furthermore, in S4, obtaining the tire pressure status includes: when two seamlessly contacting electrodes slide laterally relative to each other, the surfaces will generate charges due to friction, and the electrical signal generated by the current alternately output during the reciprocating sliding of the electrodes during polarization is obtained.

[0015] The tire pressure is determined by the magnitude of the generated electrical signal.

[0016] Furthermore, under normal tire pressure, the electrical signal increases significantly with increasing load.

[0017] Furthermore, the judgment valve domain specifically includes: when the tire pressure is insufficient (<100kPa), an open circuit voltage of 13±0.5V can be detected;

[0018] When the tire pressure is normal, an open circuit voltage of 15±0.5V is detected;

[0019] When the tire pressure is too high (>150kPa), the contact area between the tire and the ground is significantly reduced, and the open circuit voltage is detected to be significantly reduced, reaching 10±0.5V.

[0020] Furthermore, when the vehicle speed reaches 2m / s and the tire pressure is insufficient (<100kPa), an open circuit voltage of 14±0.5V can be detected.

[0021] When the tire pressure is normal, an open circuit voltage of 17±0.5V can be detected;

[0022] When the tire pressure is too high (>150kPa), the open circuit voltage can reach 9±0.5V.

[0023] Furthermore, at a vehicle speed of 1.5 m / s, an open-circuit voltage of 13 ± 0.5 V is generated under no-load conditions;

[0024] When the load is increased to 40N, the open circuit voltage is 32V; when the load is increased to 120N, the open circuit voltage is 38V.

[0025] Furthermore, at a vehicle speed of 2 m / s, the open-circuit voltage is 38 V when the load increases to 40 N; and 43 V when the load increases to 120 N.

[0026] Another object of the present invention is to disclose a device for monitoring the internal pressure of a tire, the device comprising:

[0027] The tire cover is configured to cover the tire with a PTFE film with a thickness of 0.13 mm and a width of 100 mm;

[0028] The pressure belt has five copper electrodes, each 10 mm wide and 0.08 mm thick, connected in parallel at equal intervals, and a 0.08 mm wide PTFE film is attached to the surface of the copper electrodes.

[0029] The operation section is configured to allow vehicles to drive on the monitoring belt via a terminal;

[0030] The monitoring section is configured to monitor the vehicle's tire pressure using an electrometer, a data acquisition card, and a display.

[0031] Furthermore, the monitoring section is configured to acquire the charge generated on the surface due to friction when two seamlessly contacting electrodes slide laterally relative to each other, acquire the electrical signal generated by the alternating current output during the polarization of the electrodes, and determine the tire pressure based on the magnitude of the electrical signal.

[0032] Furthermore, under normal tire pressure, the monitored electrical signal increases significantly with increasing load.

[0033] Beneficial effects:

[0034] This invention provides a method for fixed-point monitoring of vehicle tire pressure based on a triboelectric nanogenerator; and provides some relevant content for verifying the theory in specific embodiments. Combined with experimental results, it can be determined that the device and method disclosed in this invention can obtain open-circuit voltage signals of different amplitudes depending on the vehicle's tire pressure, speed, and load, thereby determining the vehicle's tire pressure status based on the magnitude of the open-circuit voltage.

[0035] Specifically, during vehicle operation, tire pressure directly affects the contact area between the tire and the ground. This technology detects tire pressure based on the electrical signals generated by the friction between the tire and the ground, avoiding the need for sensors on the tires required by traditional direct and indirect monitoring systems. This reduces tire pressure monitoring costs and improves the reliability of the monitoring signal and the lifespan of the system. Compared to other traditional tire pressure monitoring methods, this technology utilizes a simpler monitoring principle and equipment, thus improving the efficiency of tire pressure monitoring.

[0036] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0037] Figure 1 This refers to the tire-ground contact shape under different tire pressure conditions as described in the embodiments of the present invention;

[0038] Figure 2 This is a diagram of the experimental apparatus described in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the horizontal sliding TENG according to an embodiment of the present invention;

[0040] Figure 4 This is a diagram of open-circuit voltage signals generated under different tire pressures at different speeds, as described in an embodiment of the present invention.

[0041] Figure 5 This is a diagram of open-circuit voltage signals generated under different loading conditions as described in the embodiments of the present invention. Detailed Implementation

[0042] To more clearly illustrate the technical solution of the present invention, the present invention will be described in detail below with reference to embodiments.

[0043] Example 1

[0044] Tire internal pressure mainly includes three typical pressure states: low pressure, normal pressure, and high pressure. Figure 1 As shown. Under normal pressure (standard tire: 120kPa), the tire and the ground are in close contact, and the tire has good grip during driving. When the tire pressure is too low (<100kPa), the tire tread is severely deformed and the tread is concave inward. At this time, the contact area between the tire and the ground increases, resulting in increased friction. This not only increases fuel consumption but also affects the handling of the vehicle. When the tire pressure is too high (>150kPa), the tire's contact area is significantly reduced. At this time, the friction and adhesion decrease, the emergency braking distance becomes longer, and rear-end collisions are more likely to occur.

[0045] Due to differences in tire application scenarios and load-bearing capacities across different vehicle models, the normal tire pressure (standard tires: 0.24-0.25 MPa, reinforced tires: 0.28-0.29 MPa) varies. This invention focuses on an electric go-kart (maximum tire pressure: 206.9 kPa, standard tire pressure: 120 kPa) for design purposes.

[0046] This invention amplifies the electrical signals obtained from tire monitoring by covering the tire with a 0.13mm thick and 100mm wide PTFE film. Five copper electrodes, each 10mm wide and 0.08mm thick, are connected in parallel at equal intervals on a PMMA plate. This allows for the generation of pulsed electrical signals with multiple cycles. By attaching a 0.08mm wide PTFE film to the surface of the copper electrodes, the directional transfer of charge on the PMMA plate is blocked, meaning the open-circuit voltage reaches its maximum value. A vehicle is driven along the monitoring belt by a remote control. The tire pressure is monitored using an electrometer, a data acquisition card, and a display. The experimental setup is shown in the diagram. Figure 2 As shown.

[0047] This invention employs the working principle of a horizontally sliding triboelectric nanogenerator, such as... Figure 3 As shown, when two seamlessly contacting electrodes slide laterally relative to each other, their surfaces will generate electrical charges due to friction, causing the electrodes to become polarized. If they slide back and forth, they will alternately output current. Since different tire pressures have different contact areas with the ground, the amount of charge generated will also be different. The magnitude of the generated electrical signal can be used to determine the tire pressure.

[0048] like Figure 4 As shown, at a vehicle speed of 1.5 m / s, when the tire pressure is insufficient (<100 kPa), an open-circuit voltage of approximately 13 V can be detected; when the tire pressure is normal, an open-circuit voltage of approximately 15 V can be detected; when the tire pressure is excessively high (>150 kPa), the contact area between the tire and the ground is significantly reduced, thus the open-circuit voltage is significantly reduced, reaching approximately 10 V. At a vehicle speed of 2 m / s, when the tire pressure is insufficient (<100 kPa), an open-circuit voltage of approximately 14 V can be detected; when the tire pressure is normal, an open-circuit voltage of approximately 17 V can be detected; when the tire pressure is excessively high (>150 kPa), the open-circuit voltage can reach approximately 9 V.

[0049] like Figure 5 As shown, under normal tire pressure, the electrical signal increases significantly with increasing load. At a vehicle speed of 1.5 m / s, the unloaded open-circuit voltage is approximately 13V. When the load increases to 40N, the open-circuit voltage is 32V, an increase of approximately 59% compared to the unloaded condition. When the load increases to 120N, the open-circuit voltage is 38V, an increase of approximately 65% ​​compared to the unloaded condition. At a vehicle speed of 2 m / s, the unloaded open-circuit voltage is approximately 14V. When the load increases to 40N, the open-circuit voltage is 38V, an increase of approximately 63% compared to the unloaded condition. When the load increases to 120N, the open-circuit voltage is 43V, an increase of approximately 67% compared to the unloaded condition.

[0050] Example 2

[0051] The methods and apparatus of this invention can be widely applied to vehicles of various types and sizes, including but not limited to cars, trucks, engineering vehicles, and agricultural vehicles. Whether on urban roads, highways, rural roads, construction sites, or other complex road conditions, the methods and apparatus of this invention can enable real-time and accurate monitoring of vehicle tire pressure.

[0052] Furthermore, the use of electrometers, data acquisition cards, and displays for tire pressure monitoring makes data acquisition and processing more convenient and efficient, and provides a clear visual representation of tire pressure changes, facilitating vehicle operation and maintenance. Additionally, the ability to store monitoring data offers valuable data support for long-term vehicle use and maintenance.

[0053] The methods and apparatus of this invention can be used not only for real-time monitoring of vehicle tire pressure, but also in other situations requiring pressure monitoring, such as industrial production, scientific research experiments, and medical equipment.

[0054] The above are merely some of the embodiments of this application and are not intended to limit the application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments shall still fall within the scope of protection of the technical solution of this application.

Claims

1. A method for monitoring the internal pressure of a tire, characterized in that, Designed for electric go-karts, with a maximum tire pressure of 206.9 kPa and a standard tire pressure of 120 kPa, the system enables point-to-point tire pressure monitoring, including the following steps: S1. Cover the tire with a PTFE film with a thickness of 0.13mm and a width of 100mm; S2, the pressure band, consists of five copper electrodes, each 10 mm wide and 0.08 mm thick, connected in parallel at equal intervals on a PMMA plate. This allows for the generation of pulsed electrical signals with multiple cycles. By attaching a 0.08 mm wide PTFE film to the surface of the copper electrodes, the directional transfer of charge on the PMMA plate is blocked, meaning the open-circuit voltage reaches its maximum value at this point. S3. The vehicle is driven on the monitoring belt via the terminal; S4. Monitor the vehicle's tire pressure using an electrometer, data acquisition card, and display. In S4, obtaining the tire pressure status includes: when two seamlessly contacting electrodes slide laterally relative to each other, the surface will generate charge due to friction, and the electrical signal generated by the current alternately output by the reciprocating sliding during the polarization of the electrodes is obtained. The tire pressure is determined by the magnitude of the generated electrical signal. Under normal tire pressure, the electrical signal will increase significantly with increasing load.

2. The method for monitoring tire internal pressure according to claim 1, characterized in that, The specific valve range for judgment includes: at a vehicle speed of 1.5 m / s, when the tire pressure is insufficient (<100 kPa), an open circuit voltage of 13 ± 0.5 V can be detected; When the tire pressure is normal, an open circuit voltage of 15±0.5V is detected; When the tire pressure is too high (>150kPa), the contact area between the tire and the ground is significantly reduced, and the open circuit voltage is detected to be significantly reduced, reaching 10±0.5V.

3. The method for monitoring tire internal pressure according to claim 1, characterized in that, When the vehicle speed reaches 2m / s, and the tire pressure is insufficient (<100kPa), an open circuit voltage of 14±0.5V can be detected. When the tire pressure is normal, an open circuit voltage of 17±0.5V can be detected; When the tire pressure is too high (>150kPa), the open circuit voltage can reach 9±0.5V.

4. The method for monitoring tire internal pressure according to claim 1, characterized in that, At a vehicle speed of 1.5 m / s, an open-circuit voltage of 13 ± 0.5 V is generated under no-load conditions; When the load is increased to 40N, the open circuit voltage is 32V; when the load is increased to 120N, the open circuit voltage is 38V.

5. The method for monitoring tire internal pressure according to claim 1, characterized in that, At a vehicle speed of 2 m / s, the open-circuit voltage is 38 V when the load is increased to 40 N; and 43 V when the load is increased to 120 N.

6. A device for monitoring the internal pressure of a tire, characterized in that, The device is used to perform the method for monitoring tire internal pressure according to any one of claims 1-5, comprising: The tire cover is configured to cover the tire with a PTFE film with a thickness of 0.13 mm and a width of 100 mm; The pressure belt has five copper electrodes, each 10 mm wide and 0.08 mm thick, connected in parallel at equal intervals, and a 0.08 mm wide PTFE film is attached to the surface of the copper electrodes. The operation section is configured to allow vehicles to drive on the monitoring belt via a terminal; The monitoring section is configured to monitor the vehicle's tire pressure using an electrometer, a data acquisition card, and a display.

7. The device for monitoring tire internal pressure according to claim 6, characterized in that, The monitoring unit is configured to acquire the charge generated by friction on the surface of two seamlessly contacting electrodes when they slide laterally relative to each other, acquire the electrical signal generated by the alternating current output during the polarization of the electrodes, and determine the tire pressure based on the magnitude of the electrical signal.

8. The device for monitoring tire internal pressure according to claim 7, characterized in that, Under normal tire pressure, the electrical signal detected by this device increases significantly with increasing load.

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