A thickness calculation method of heavy engineering vehicle brake pad

Abstract

The application discloses a kind of thickness calculation methods of heavy engineering vehicle brake pad, comprising the following steps: step one: obtaining the initial nominal thickness H0 of brake pad;Step two: real-time collection brake pad temperature data in the running process of heavy engineering vehicle, and simultaneously obtaining the brake state signal of vehicle;Step three: according to the brake state signal and the temperature data, first extract single brake process characteristics, then define different brake states;By introducing material correction coefficient, and combining vehicle maximum load and external environment temperature for dynamic correction, the problem that wear law is inconsistent under different load and climate environment of heavy trailer is solved, so that the calculation result of residual thickness is closer to real physical value.

Description

Technical Field

[0001] This invention relates to a method for calculating the thickness of brake pads for heavy-duty engineering vehicles, belonging to the field of motor vehicles. Background Technology

[0002] During long-distance transport, especially on long downhill sections in mountainous areas, the braking system of heavy-duty trailers bears a tremendous load. As a core wear component of the braking system, the remaining thickness of the brake pads directly affects driving safety.

[0003] Currently, the industry mainly relies on the following methods to monitor brake pad wear: Mileage estimation method: Replace brake pads periodically based on mileage. However, the wear rate of heavy trailer brake pads can vary by several times or even tens of times depending on whether they are fully loaded or empty, or whether they are used in plains or mountains. Mileage estimation method can easily lead to premature replacement, resulting in waste, or exceed the service life and cause accidents.

[0004] A metal part is installed on the outside of the brake pads. When the brake pads wear down to a certain extent, the metal part contacts the brake disc and makes a metallic sound to alert the driver. However, the trailer itself is very noisy when it is in motion, making it very easy for the driver to ignore the metallic warning sound. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a method for calculating the thickness of brake pads for heavy engineering vehicles, so as to solve the problem.

[0006] To achieve the above objectives, the present invention provides a method for calculating the thickness of brake pads for heavy-duty engineering vehicles, comprising the following steps: Step 1: Obtain the initial nominal thickness H0 of the brake pads; Step 2: Collect brake pad temperature data of heavy engineering vehicles in real time during operation, and simultaneously acquire vehicle braking status signals; Step 3: Based on the braking status signal and the temperature data, first extract the features of a single braking process, and then define them as different braking states; the specific method for extracting the features of a single braking process is as follows: S31: Based on the start and end of the braking status signal, record the start time t0 and end time t1 of a single braking action, and calculate the duration of a single braking action Δt = t1 - t0. S32: Extract the current temperature T0 and peak temperature T1 within the braking cycle, and calculate the maximum temperature difference ΔT = T1 - T0 for a single braking cycle; If △t < th and △T < Th, then the current braking behavior is determined to be in the intermittent braking state; if △t ≥ th and △T ≥ Th, then the current braking behavior is determined to be in the long braking state; where th is the set time threshold and Th is the set temperature difference threshold. Step 4: Based on the classified point braking state and long braking state, and combined with the braking duration characteristics and temperature difference characteristics, calculate the single braking wear amount ΔU = K × f(ΔT) × g(Δt), where K is the material correction coefficient, f(ΔT) is the temperature difference wear weight function with the maximum temperature difference ΔT as the independent variable, and g(Δt) is the time action function with the single braking duration Δt as the independent variable; when it is determined to be a point braking state, f(ΔT) takes a linear constant weight; when it is determined to be a long braking state, f(ΔT) takes a non-linear increasing weight. Step 5: Sum the wear amounts of each brake application during the vehicle's operating cycle to obtain the total wear amount, and calculate the remaining thickness H1 of the brake pad based on the initial nominal thickness H0 and the total wear amount.

[0007] Preferably, in step two, the brake pad temperature data is acquired through a non-contact infrared detection structure; the non-contact infrared detection structure includes an infrared thermometer mounted on the brake caliper bracket; the measurement field of the infrared thermometer covers the side edge of the brake pad, and is used to capture the thermal radiation signal of the brake pad in real time and convert it into temperature data.

[0008] Preferably, step four also includes an extreme condition compensation mechanism, with the critical degradation temperature of the brake pad material preset to TL; when the peak temperature T1 > TL is detected during a single braking process, U0 will be compensated in the calculation of the wear amount △U during a single braking process, that is, △U = K × f (△T) × g (△t) + U0.

[0009] Preferably, in step five, the formula for calculating H1 is H1 = H0 - ;in, For the first The amount of wear generated by each braking action. This represents the total number of braking operations since the initial nominal thickness H0 was entered.

[0010] Preferably, after calculating the remaining thickness H1 of the current brake pad, a safety warning step is also included: S51: Set the warning thickness threshold H2 and the extreme thickness threshold H3, where H2>H3; S52: When H1≤H2 and H1>H3, a level 1 alarm is triggered; S53: When H1≤H3, a level 2 mandatory alarm is triggered.

[0011] Preferably, in step four, the specific model of the temperature difference wear weighting function f(ΔT) is as follows: When the braking state is determined to be point braking, f(△T) = a×△T+b, where a represents the basic wear rate of the material and b is the initial compensation constant when considering the intervention of braking pressure. When the braking state is determined to be long braking, f(△T) = c × (△T) 2 +d×△T, where c and d are nonlinear characteristic parameters obtained by fitting through high-temperature friction and wear tests of materials.

[0012] Preferably, in step four, the specific model of the time action function g(Δt) is as follows: g(Δt) = (Δt) e Where e is the wear time index, with a value range of 1.0≤e≤1.5; the wear time e is used to set the wear amount △U of a single braking operation to increase non-linearly with the increase of the duration △t, in order to compensate for the increase in wear efficiency caused by the accumulation of braking energy under long-distance braking conditions.

[0013] Preferably, the steps for determining the material correction factor K include: S41: Based on the vehicle's maximum load capacity M, match the corresponding load gain α; S42: Obtain the external temperature T3 through the temperature sensor in the trailer, and match compensation β according to the influence of the external temperature T3 on the heat dissipation rate of the brake pads; S43: The comprehensive calculation of the material correction coefficient K=α×β is used to dynamically correct the wear of the foundation under different loads and environmental conditions.

[0014] Preferably, the front side of the infrared thermometer is covered with quartz glass with high light transmittance.

[0015] Preferably, the measuring spot of the infrared thermometer is controlled within a range of 5mm to 10mm from the side edge of the brake pad.

[0016] Beneficial effects This invention solves the problem of inconsistent wear patterns of heavy trailers under different loads and climates by introducing a material correction coefficient and combining it with the vehicle's maximum load capacity and external ambient temperature for dynamic correction, making the calculated remaining thickness closer to the actual physical value. By using time thresholds and temperature difference thresholds, it accurately identifies point braking and long braking states. For point braking, a linear constant weight is used, and for long braking, a quadratic function and power law model are used to compensate for the heat energy accumulation effect, accurately capturing the nonlinear wear jump characteristics of friction materials under high temperature and high energy consumption. Attached Figure Description

[0017] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the brake disc and brake caliper bracket structure of the present invention; Figure 2 This is a bottom view of the brake pad structure of the present invention.

[0018] In the diagram: Brake pad-1, Brake disc-2, Brake caliper bracket-3, Infrared thermometer-4, Mounting hole-5. Detailed Implementation

[0019] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0020] Please see Figure 1 , Figure 2 This invention provides a technical solution for calculating the thickness of brake pads for heavy-duty engineering vehicles, comprising the following steps: Step 1: Obtain the initial nominal thickness H0 of brake pad 1; Step 2: Collect the temperature data of brake pads 1 of heavy engineering vehicles in real time during operation, and simultaneously acquire the vehicle's braking status signal; Step 3: Based on the braking status signal and the temperature data, first extract the features of a single braking process, and then define them as different braking states; the specific method for extracting the features of a single braking process is as follows: S31: Based on the start and end of the braking status signal, record the start time t0 and end time t1 of a single braking action, and calculate the duration of a single braking action Δt = t1 - t0. S32: Extract the current temperature T0 and peak temperature T1 within the braking cycle, and calculate the maximum temperature difference ΔT = T1 - T0 for a single braking cycle; If △t < th and △T < Th, then the current braking behavior is determined to be in the intermittent braking state; if △t ≥ th and △T ≥ Th, then the current braking behavior is determined to be in the long braking state; where th is the set time threshold and Th is the set temperature difference threshold. Step 4: Based on the classified point braking state and long braking state, and combined with the braking duration characteristics and temperature difference characteristics, calculate the single braking wear amount ΔU = K × f(ΔT) × g(Δt), where K is the material correction coefficient, f(ΔT) is the temperature difference wear weight function with the maximum temperature difference ΔT as the independent variable, and g(Δt) is the time action function with the single braking duration Δt as the independent variable; when it is determined to be a point braking state, f(ΔT) takes a linear constant weight; when it is determined to be a long braking state, f(ΔT) takes a non-linear increasing weight. Step 5: Sum the wear amounts of each brake application during the vehicle's operating cycle to obtain the total wear amount, and calculate the remaining thickness H1 of the current brake pad 1 based on the initial nominal thickness H0 and the total wear amount.

[0021] In one embodiment, the infrared thermometer 4 is fixed to the brake caliper bracket 3. The measuring spot of the infrared thermometer 4 is controlled within a range of 5mm to 10mm from the side edge of the brake pad 1 to ensure that the measurement is of the thermal radiation of the friction material, rather than the interfering heat of the brake disc 2 or the caliper backplate.

[0022] Due to the dusty and muddy driving environment of heavy-duty trailers, the front of the infrared thermometer 4 is covered with a layer of high-transmittance quartz glass. This quartz glass has extremely high infrared transmittance (>95%) and an extremely low coefficient of thermal expansion, enabling it to withstand the thermal radiation impact generated by the instantaneous heating of the brake pads 1 without shattering. Simultaneously, the quartz glass acts as a physical barrier, preventing brake dust from directly corroding the optical lens. In the specific structure, this quartz glass is embedded in the thermometer housing through a high-temperature resistant fluororubber sealing ring, ensuring that the internal sealing level of the component reaches IP67 or even IP69K, sufficient to withstand the washing of a high-pressure water gun.

[0023] The method of this invention not only relies on the temperature of the brake pad 1 body, but also needs to be dynamically corrected in combination with the vehicle's load and environmental factors. Based on the trailer's maximum load capacity M (vehicle weight and maximum load) from the manufacturer's information, a corresponding load gain α is matched to adapt to the different braking energy consumption caused by different maximum load capacities M of different vehicles.

[0024] An external temperature sensor, T3, is typically installed near the trailer axle or on a chassis crossbeam unaffected by brake heat. This sensor is usually a PT1000 high-precision resistance temperature detector (RTD) encapsulated in a metal housing with a ventilation hood to prevent direct sunlight. The external temperature T3 is used to calculate the temperature difference between the brake pad 1 and the environment, thereby matching the heat dissipation compensation coefficient β. For example, in extremely cold environments, the natural heat dissipation rate of the brake pad 1 is significantly higher than in hot environments. By dynamically adjusting β, errors in wear calculation caused by environmental differences can be corrected.

[0025] In the disc brake structure, the installer needs to drill a mounting hole 5 in the non-stressed area of ​​the brake caliper bracket 3. The infrared thermometer 4 is fixed to the mounting hole 5 by hardware components. Preferably, during installation, the infrared beam of the infrared thermometer 4 should fall on the center thickness line of the brake pad 1. This way, even if the brake pad 1 becomes thinner with use, the central area of ​​the friction material will still remain within the effective field of view of the infrared thermometer 4, and the measurement target will not be lost due to wear.

[0026] In step one, after the first run or after replacing the brake pad 1 with a brand new one, the initial thickness is entered. The initial nominal thickness H0 of the brake pad 1 is usually provided by the brake pad 1 manufacturer. However, in a specific embodiment, after replacing the brake pad 1, the maintenance personnel need to access the vehicle system through the existing vehicle communication interface and input the initial nominal thickness H0 of the brake pad 1.

[0027] In steps three and four, to obtain the constants a and b, and the nonlinear characteristic parameters c and d, these are set according to the manufacturer's production report. In one embodiment, at medium and low temperatures (e.g., T1 < 200°C), the report shows that the wear amount has a quasi-linear relationship with temperature rise. Based on this, the least squares method can be used to fit and derive the linear equation f(ΔT) = a × ΔT + b. The report shows that when the peak temperature T1 > the critical degradation temperature TL, the wear amount increases exponentially. At this time, the quadratic coefficient c and the linear coefficient d are obtained through polynomial fitting, and a nonlinear model f(ΔT) = c × (ΔT) is constructed. 2 +d×△T. In one embodiment, the brake pad 1 manufacturer observes the impact of the depth of heat penetration into the material on structural strength by changing the braking duration, and measures that the wear time index e of this batch of brake pads 1 under heavy load conditions is stable between 1.0 and 1.5. In one embodiment, the maximum load capacity M of the vehicle directly determines the normal pressure during braking, so a corresponding dynamic matching α value can be matched according to the current trailer model. In one embodiment, the heat dissipation rate directly affects the heat residence time on the surface of brake pad 1, so when the external temperature T3 is high (such as in summer), the compensation coefficient β is increased to compensate for the risk of continuous wear caused by the slow heat dissipation rate; conversely, in the low temperature of winter, due to the high efficiency of natural air cooling, β is appropriately reduced, ultimately realizing the dynamic correction logic of material correction coefficient K=α×β.

[0028] Furthermore, the calibration of the time threshold th and the temperature difference threshold Th directly determines the accuracy of identifying point braking state and long braking state. Based on driving statistics of heavy engineering vehicles, conventional adaptive braking is typically completed within 3 seconds. Therefore, in one embodiment, the time threshold th is preferably set to 3 seconds.

[0029] According to the heat capacity calibration of brake pad 1, the temperature rise during a single braking maneuver typically does not exceed 30°C. Once the temperature rise ΔT exceeds 50°C, it means that the brake has absorbed a large amount of mechanical energy. Therefore, in this embodiment, the temperature difference threshold Th is set at 50°C.

[0030] To prevent extreme overheating conditions, the critical degradation temperature of brake pad material 1 is preset to TL; when the peak temperature T1 > TL is detected during a single braking process, U0 will be compensated in the calculation of the wear amount △U during a single braking process, that is, △U = K × f (△T) × g (△t) + U0.

[0031] To ensure the onboard system can perform real-time calculations under complex driving environments, it is preferable not to run complex power-law or high-order polynomial operations on the vehicle end, but to use a calibration lookup table method. Specifically, the values ​​of the material correction coefficient K, the temperature difference wear weighting function f(ΔT), and the time action function g(Δt) obtained from the calibration are converted into a multi-dimensional data matrix with the maximum temperature difference ΔT during a single braking event, the duration Δt of a single braking event, the maximum vehicle load capacity M, and the external temperature T3 as axes. The generated MAP data table is then burned into the onboard system's non-volatile memory in hexadecimal file format. Thus, when the vehicle is running, the controller only needs to read the real-time sensor data, perform address lookups in the memory, and perform bilinear interpolation to determine the wear amount generated during that braking event. .

[0032] In step two, because heavy-duty trailers experience drastic temperature changes and high-frequency vibrations during braking, the quality of the original signal directly determines the accuracy of the identification. The onboard system monitors the braking request signal output by the trailer's electronic auxiliary control system (such as EBS or ABS) in real time. This signal has a clear binary characteristic (0 represents release, 1 represents braking) and serves as a trigger for the identification process. Furthermore, to ensure that the temperature change and braking action are perfectly synchronized on the timeline, the onboard system is equipped with a high-precision timer. When the braking signal changes from 0 to 1, the onboard system immediately locks that moment as the starting point t0 and extracts the corresponding instantaneous temperature T0.

[0033] Preferably, after extracting the peak temperature T1, the vehicle system immediately compares it with the preset critical material degradation temperature TL. If T1 > TL, regardless of the current state, the vehicle system determines that the friction material has undergone irreversible physical structural changes (such as surface ablation or organic carbonization). In this case, the process forces the addition of a fixed compensation term U0 to the single wear calculation to cover the additional wear that cannot be captured by conventional formulas due to material failure.

[0034] To address the potential for "repeated braking" by heavy trailers on a long slope, if the interval between two braking actions is extremely short (e.g., less than 3 seconds), the onboard system will determine that the brake disc 2 has not yet cooled down. The current temperature T0 of the second braking action will be significantly higher than that of the first. The higher current temperature T0 will result in a smaller calculated maximum temperature difference ΔT for a single braking action. However, the onboard system identifies the current high-heat environment through the heat dissipation compensation term β of the material correction coefficient K, thereby maintaining a high wear weight and avoiding misjudgment.

[0035] In step five, the formula for calculating H1 is H1 = H0 - ;in, For the first The amount of wear generated by each braking action. This represents the total number of braking operations since the initial nominal thickness H0 was entered.

[0036] After calculating the remaining thickness H1 of the current brake pad 1, a safety warning step is also included: S51: Set the warning thickness threshold H2 and the extreme thickness threshold H3, where H2>H3; S52: When H1≤H2 and H1>H3, a level 1 alarm is triggered; S53: When H1≤H3, a level 2 mandatory alarm is triggered.

[0037] In one embodiment, during intermittent braking, due to the short braking time and low energy density, the binder of the friction material has not yet undergone thermal degradation. At this time, wear is primarily governed by the friction path and exhibits a linear relationship with temperature rise. f(△T) = a × △T + b Where a represents the basic wear rate of the material, and b is the initial compensation constant when considering the intervention of braking pressure.

[0038] Under intermittent braking conditions, the exponent e of g(Δt) approaches 1.0, meaning that the wear is linearly proportional to the braking time. The calculation unit substitutes the measured Δt into the value to obtain the contribution value in the time dimension.

[0039] The vehicle system quickly calculates the wear caused by this braking action using the formula △U=K×(a×△T+b)×g(△t).

[0040] Under high-temperature conditions, the organic resin on the surface of brake pad 1 begins to soften or even carbonize, leading to a decrease in material strength and a non-linear increase in the wear rate. The vehicle system invokes a quadratic equation: f(△T) = c × (△T) 2 +d×△T, where c and d are nonlinear characteristic parameters obtained by fitting through high-temperature friction and wear tests of the material; due to the existence of (△T) 2 When the temperature difference increases from 100℃ to 200℃, the weight of the function output increases by more than double. This accurately simulates the severe wear characteristics of heavy trailers near the thermal decay critical point.

[0041] For long braking systems, heat penetration into deeper layers of the material has a cumulative destructive effect. A power-law model is adopted: g(Δt) = (Δt) e , where e is the wear time index, with a value range of 1.0 ≤ e ≤ 1.5; when e > 1, the wear increment per unit time continuously increases with the extension of braking time. This compensates for the additional losses caused by the thermal expansion of the brake disc 2, changes in contact area, and fatigue spalling of the friction surface due to long-term braking.

[0042] The vehicle system integrates all nonlinear terms and calculates ΔU = K × (c × (ΔT)). 2 +d×△T)×(△t) e This calculation captures the true physical processes of accelerated wear at the end of a long slope.

[0043] The calculation unit extracts the peak temperature T1 of this braking event. If T1 exceeds the material's critical degradation temperature TL, it indicates that a violent thermochemical reaction has occurred on the friction surface. In this extreme case, conventional continuous functions may underestimate instantaneous material loss. The onboard system executes: △U = K × f(△T) × g(△t) + U0, where U0 is a step constant based on brake pad 1, representing the expected spalling thickness of the material at the moment of high-temperature failure. This mechanism provides a final layer of protection for safety.

[0044] The calculated single wear amount △U needs to be updated in a closed loop from the thickness in the physical dimension.

[0045] The vehicle system includes a highly reliable counter. After each braking operation, the onboard system will generate... (That is, the thickness representation of △U) is stored in non-volatile memory: Using the formula, H1=H0- The vehicle system updates the remaining thickness of brake pad 1 in real time.

[0046] Example 1 Before the vehicle is put into operation, the hardware system must first be installed and its parameters initialized. The infrared thermometer 4 is fixed in the non-stress area mounting hole 5 of the brake caliper bracket 3. The maintenance personnel input the initial nominal thickness H0=22.5mm of the newly replaced brake pad 1 into the vehicle system through the vehicle communication interface.

[0047] The non-volatile memory of the vehicle system pre-programs a multidimensional data MAP table, which includes linear constants a and b, nonlinear characteristic parameters c and d, and wear time index e fitted for this batch of brake pad material 1. In this embodiment, the time threshold th = 3s, the temperature difference threshold Th = 50℃, and the critical degradation temperature TL = 350℃ are set.

[0048] When the vehicle reached the downhill section, the driver applied continuous braking: The vehicle system monitors the EBS signal in real time. When the braking request signal changes from 0 to 1, the vehicle system triggers a timer to record the starting time t0 and simultaneously reads the instantaneous temperature T0 = 80℃ at that moment through the infrared thermometer 4.

[0049] During braking, the infrared thermometer 4 collects thermal radiation signals at high frequency and converts them into temperature stream data. When the braking signal returns to 0, the vehicle-mounted system records the end time t1.

[0050] The vehicle-mounted system calculates that the duration of a single brake is △t = t1 - t0 = 12 s. At the same time, the peak temperature T1 = 200 °C is extracted from the collected temperature stream, and the maximum temperature difference of a single brake is calculated as △T = T1 - T0 = 120 °C.

[0051] The vehicle-mounted system compares the extracted features with the thresholds: Since △t (12 s) > th (3 s) and △T (120 °C) > Th (50 °C), the vehicle-mounted system determines that the current braking behavior is in the long-brake state.

[0052] The vehicle-mounted system calls the corresponding mathematical model according to the recognized state for calculation: Determination of the correction coefficient K: The vehicle-mounted system obtains the maximum load capacity M of the current trailer as 40 tons, and the load gain α = 1.2 is matched; at the same time, the external temperature T3 = 30 °C is obtained through an external temperature sensor, and the heat dissipation compensation β = 1.1 is matched (the heat dissipation is slow in summer at high temperatures). Through comprehensive calculation, K = α × β = 1.32.

[0053] Since it is determined to be in the long-brake state, the vehicle-mounted system calls the non-linear weight model f(△T) = c × (△T) 2 + d × △T and g(△t) = (△t) e .

[0054] The vehicle-mounted system performs addressing and bilinear interpolation operations in the MAP data table of the memory according to the real-time data. After calculation, the theoretical thickness consumption of this braking = 0.015 mm.

[0055] The vehicle-mounted system checks that the peak temperature T1 (200 °C) < TL (350 °C), and the extreme condition supplement mechanism is not triggered. Therefore, the single wear amount does not need to be superimposed with the compensation term U0.

[0056] The vehicle-mounted system includes the wear amount generated this time in the total wear amount, and uses the formula H1 = H0 - to update the remaining thickness.

[0057] The vehicle-mounted system compares the updated H1 in real time. If H1 drops to 6 mm (warning threshold H2), a first-level yellow warning on the dashboard is triggered; if it drops to 3 mm (limit threshold H3), a second-level red forced alarm is triggered, prompting the driver to immediately replace the brake pad 1.

[0058] Embodiment 2 Unlike Example 1, the vehicle system determines that the current braking action is in a point braking state. The system calls the linear constant weighting function f(ΔT) = a × ΔT + b for point braking. Due to the point braking condition, the exponent e of the time action function g(Δt) approaches 1.0, meaning the wear is linearly proportional to the braking time. The vehicle system quickly calculates the minute wear caused by this point braking using the formula ΔU = K × (a × ΔT + b) × g(Δt). .

[0059] Example 3 Unlike Example 1, this simulation depicts a heavy-duty trailer under extreme conditions where brake pad 1 experiences severe thermal degradation; the driver performs a high-intensity emergency braking. The onboard system records the duration of a single braking event, Δt = 15 seconds, and extracts the peak temperature, T1 = 420℃. Since T1 (420℃) is greater than TL (350℃), a fixed compensation term U0 is forcibly added to the calculation results, i.e., ΔU = K × f(ΔT) × g(Δt) + U0, to quickly calculate the wear amount caused by this braking event. .

[0060] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for calculating the thickness of brake pads for heavy-duty engineering vehicles, characterized in that: Includes the following steps: Step 1: Obtain the initial nominal thickness H0 of the brake pads; Step 2: Collect brake pad temperature data of heavy engineering vehicles in real time during operation, and simultaneously acquire vehicle braking status signals; Step 3: Based on the braking status signal and the temperature data, first extract the features of a single braking process, and then define them as different braking states; the specific method for extracting the features of a single braking process is as follows: S31: Based on the start and end of the braking status signal, record the start time t0 and end time t1 of a single braking action, and calculate the duration of a single braking action Δt = t1 - t0. S32: Extract the current temperature T0 and peak temperature T1 within the braking cycle, and calculate the maximum temperature difference ΔT = T1 - T0 for a single braking cycle; If △t < th and △T < Th, then the current braking behavior is determined to be in the intermittent braking state; if △t ≥ th and △T ≥ Th, then the current braking behavior is determined to be in the long braking state; where th is the set time threshold and Th is the set temperature difference threshold. Step 4: Based on the classified point braking state and long braking state, and combined with the braking duration characteristics and temperature difference characteristics, calculate the single braking wear amount ΔU = K × f(ΔT) × g(Δt), where K is the material correction coefficient, f(ΔT) is the temperature difference wear weight function with the maximum temperature difference ΔT as the independent variable, and g(Δt) is the time action function with the single braking duration Δt as the independent variable; when it is determined to be a point braking state, f(ΔT) takes a linear constant weight; when it is determined to be a long braking state, f(ΔT) takes a non-linear increasing weight. Step 5: Sum the wear amounts of each brake application during the vehicle's operating cycle to obtain the total wear amount, and calculate the remaining thickness H1 of the brake pad based on the initial nominal thickness H0 and the total wear amount.

2. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 1, characterized in that: In step two, the brake pad temperature data is acquired through a non-contact infrared detection structure; the non-contact infrared detection structure includes an infrared thermometer mounted on the brake caliper bracket; the measurement field of the infrared thermometer covers the side edge of the brake pad, and is used to capture the thermal radiation signal of the brake pad in real time and convert it into temperature data.

3. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 1, characterized in that: Step four also includes an extreme condition compensation mechanism, with the critical degradation temperature of the brake pad material preset to TL; when the peak temperature T1 > TL is detected during a single braking process, U0 will be compensated in the calculation of the wear amount △U during a single braking process, that is, △U = K × f (△T) × g (△t) + U0.

4. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 1, characterized in that: In step five, the formula for calculating H1 is H1 = H0 - ;in, For the first The amount of wear generated by each braking action. This represents the total number of braking operations since the initial nominal thickness H0 was entered.

5. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 4, characterized in that: After calculating the remaining thickness H1 of the brake pads, a safety warning step is also included: S51: Set the warning thickness threshold H2 and the extreme thickness threshold H3, where H2>H3; S52: When H1≤H2 and H1>H3, a level 1 alarm is triggered; S53: When H1≤H3, a level 2 mandatory alarm is triggered.

6. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 1, characterized in that: In step four, the specific model of the temperature difference wear weighting function f(ΔT) is as follows: When the braking state is determined to be point braking, f(△T) = a×△T+b, where a represents the basic wear rate of the material and b is the initial compensation constant when considering the intervention of braking pressure. When the braking state is determined to be long braking, f(△T) = c × (△T) 2 +d×△T, where c and d are nonlinear characteristic parameters obtained by fitting through high-temperature friction and wear tests of materials.

7. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 1, characterized in that: In step four, the specific model of the time action function g(Δt) is as follows: g(Δt) = (Δt) e Where e is the wear time index, with a value range of 1.0≤e≤1.5; the wear time e is used to set the wear amount △U of a single braking operation to increase non-linearly with the increase of the duration △t, in order to compensate for the increase in wear efficiency caused by the accumulation of braking energy under long-distance braking conditions.

8. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 1, characterized in that: The steps for determining the material correction factor K include: S41: Based on the vehicle's maximum load capacity M, match the corresponding load gain α; S42: Obtain the external temperature T3 through the temperature sensor in the trailer, and match compensation β according to the influence of the external temperature T3 on the heat dissipation rate of the brake pads; S43: The comprehensive calculation of the material correction coefficient K=α×β is used to dynamically correct the wear of the foundation under different loads and environmental conditions.

9. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 2, characterized in that: The front of the infrared thermometer is covered with quartz glass with high light transmittance.

10. The method for calculating the thickness of brake pads for heavy-duty engineering vehicles according to claim 2, characterized in that: The measuring spot of the infrared thermometer is controlled within a range of 5mm to 10mm from the side edge of the brake pad.

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