Tool for automatically measuring pavement flatness

Abstract

The invention relates to the technical field of constructional engineering, in particular to an automatic pavement flatness measuring tool which comprises a tool body, a groove, a track, a distance measuring sensor, a pulley and a pulley mounting groove, the top of the tool body is provided with a non-through groove, the track is fixed on the inner side wall of the groove, and the distance measuring sensor is slidably assembled on the track; at least four groups of pulley mounting grooves are formed in four top corners of the bottom of the tool body, and pulleys are arranged in the pulley mounting grooves to form pulley blocks; the distance measuring sensor is in signal connection with an external data processing terminal, the tool is moved to a target area through the pulley block, the distance measuring sensor is started to slide along a track at a constant speed, road height data are collected in real time and transmitted to the terminal, and the terminal calculates the maximum fluctuation error and the average error through a standardization algorithm and automatically judges whether the flatness is qualified or not. The method realizes automatic detection, is convenient to operate, is high in detection efficiency, is reliable in precision, is suitable for various pavement structure layers and complex construction scenes, and provides powerful support for road engineering quality control.

Description

Technical Field

[0001] This invention relates to the field of building engineering technology, specifically to an automatic tool for measuring road surface smoothness. Background Technology

[0002] With the deepening of the national strategy for new urbanization and urban infrastructure renewal, road construction projects have entered a period of large-scale development, with a continuous increase in the number of various road projects, including urban main roads, highways, municipal branch roads, and residential roads. Road surface smoothness, as one of the core evaluation indicators of road construction quality, directly affects driving safety, comfort, and the service life of the road. Poor road surface smoothness not only increases vehicle rolling resistance and accelerates tire wear, but may also cause road surface cracking, settlement, and other defects due to localized stress concentration, shortening the road's service life. Therefore, strict smoothness testing must be carried out during the construction of each structural layer of the road.

[0003] Currently, the industry primarily relies on traditional manual methods for inspecting the smoothness of various road surface structural layers, with the core tools being a combination of a straightedge and a feeler gauge. The specific inspection process is as follows: workers manually carry a straightedge of fixed length, place it across the area to be inspected, visually observe the gap between the straightedge and the road surface, and then use a feeler gauge to measure the maximum gap value at each point in the gap. This value is used as the smoothness error data for that area. After measurement, the data is manually recorded and calculated; only after confirmation of compliance can the next stage of construction proceed. This traditional inspection method has long been the mainstream approach in the industry, playing a fundamental role in small-scale road projects or low-frequency inspection scenarios.

[0004] However, with the expansion of road construction scale, the acceleration of construction pace, and the continuous improvement of engineering quality requirements, the drawbacks of traditional manual inspection methods have become increasingly prominent, making it difficult to meet the actual needs of current engineering construction. Firstly, the inspection efficiency is extremely low: the handling, positioning, and adjustment of the straightedge all require manual labor, and single-area inspections require multiple repetitions. For large-scale road projects, the inspection work is time-consuming, often causing construction procedures to be interrupted while waiting for inspection results, seriously affecting construction progress and increasing the risk of project delays. Secondly, the measurement accuracy is unstable: the inspection results are highly dependent on the operator's experience and sense of responsibility. Subjective factors such as the angle of the straightedge placement, the force of the feeler gauge insertion, and the accuracy of gap observation can all lead to measurement errors. The consistency of inspection results among different operators is low, making it difficult to objectively and accurately reflect the road conditions. The actual flatness of the surface can easily lead to the omission of unqualified areas or the misjudgment of qualified areas. Furthermore, labor and indirect costs are high: large-area inspection requires multiple staff to work together, resulting in a large labor input and high labor costs in the long run. At the same time, rework caused by inaccurate inspection will result in the loss of building materials and wasted time, further increasing the overall cost of the project. In addition, traditional inspection methods have limited adaptability. On rough roads, in narrow working spaces, or in high-slope areas, it is difficult to place the ruler stably, making the inspection operation difficult or even impossible to carry out effective inspection, which limits its application in complex construction scenarios.

[0005] In summary, existing road surface evenness testing technologies suffer from significant drawbacks, including low efficiency, poor accuracy, high cost, and insufficient adaptability, becoming a key bottleneck restricting the quality and progress of road construction projects. Against this backdrop, developing a road surface evenness measurement tool that can achieve automated testing, improve testing efficiency and accuracy, reduce costs, and has a wide range of applications has become an urgent need in the current road construction industry. Summary of the Invention

[0006] The purpose of this invention is to provide an automatic tool for measuring road surface smoothness, so as to solve the prominent problems of low efficiency, poor accuracy, high cost and insufficient adaptability of existing road surface smoothness detection technology mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: An automatic road surface smoothness measuring tool includes a tool body. A groove is formed along the length of the top of the tool body. The tool body is characterized by having a track symmetrically fixed to the inner wall of the groove, on which a distance measuring sensor for accurately collecting road surface unevenness data is slidably mounted. At the four corners of the bottom of the tool body, a set of pulley mounting slots is provided, with no fewer than four sets of pulley mounting slots. Each pulley mounting slot is rotatably connected to a pulley, and all the pulleys together form a pulley group for tool movement. The distance sensor establishes a signal connection with an external data processing terminal. After the tool body is quickly moved to the target measurement position by the pulley system, the distance sensor slides at a constant speed along the track, collects the flatness data of each structural layer of the road surface in real time and transmits it to the data processing terminal. After analysis by the terminal, the road surface flatness error value is output, realizing the automated measurement of road surface flatness.

[0008] Preferably, the tool body is integrally cast from high-strength aluminum alloy, and its external dimensions are as follows: length 3000mm, width 250mm, height 100mm in normal working condition, groove depth 35-45mm, width matching the assembly width of the track, and the length of the groove is less than the length of the tool body. A distance of 50-80mm is left between the two ends of the groove and the end of the tool body. The length of the track is exactly the same as the length of the groove, ensuring that the measurement coverage of the ranging sensor matches the effective measurement span of the tool body.

[0009] Preferably, the pulley system consists of at least four sets of pulleys, which are correspondingly installed in the pulley mounting slots at the four corners of the bottom of the tool body. If additional pulleys are provided, they are evenly distributed in the middle area of ​​the bottom surface between the four corner pulleys. Each pulley's shaft is fitted with wear-resistant ball bearings at both ends, and the outer circumference of the pulley is covered with an anti-slip and wear-resistant rubber sleeve. The surface of the rubber sleeve has anti-slip textures, the rubber sleeve thickness is 6-8mm, and the diameter of the pulley is 50-60mm, ensuring that the tool can move smoothly on rough surfaces.

[0010] Preferably, the ranging sensor has sliding blocks adapted to the track fixed on both sides. The inner side of the sliding block has a guide groove adapted to the protrusion of the track, and the guide groove is coated with grease. The ranging sensor has a built-in micro drive module, which is connected to the sliding block for transmission. It can drive the ranging sensor to slide at a uniform speed of 0.1-0.3m / s along the track, and the sliding stroke is consistent with the length of the track. During the sliding process, the distance between the measuring points of the ranging sensor is no more than 5mm. The track is a high-precision linear guide rail, and limit buffer blocks are fixed at both ends of the track. The limit buffer blocks are made of elastic polyurethane material with a thickness of 10-15mm. The limit buffer blocks are set corresponding to the ends of the ranging sensor, and the inner side of the limit buffer block has an arc-shaped buffer surface to limit the sliding limit position of the ranging sensor and avoid rigid collision damage.

[0011] Preferably, a dustproof cover is detachably installed at the opening of the groove. The cover is made of transparent polycarbonate material and its length is the same as that of the groove. The edge of the cover has a buckle structure, which is used to fix it to the edge of the groove opening. The inner surface of the cover is covered with a dustproof velvet layer with a thickness of 2-3mm, which can prevent construction dust and debris from entering the groove and contaminating the track and the distance sensor.

[0012] Preferably, the signal connection between the ranging sensor and the data processing terminal is a wireless communication connection, specifically including Bluetooth 5.0, Wi-Fi 6, or a 4G / 5G network module. The data processing terminal is a smartphone or a dedicated tablet, and the terminal has built-in road surface smoothness analysis software. The analysis software calculates the road surface smoothness parameters using the following formula: Maximum fluctuation error: Δh max =h max -h min , where h max h is the maximum height value among all measurement points collected by the distance sensor. min The minimum height value among all measurement points; Average error: ,in The total number of measurement points. Let i be the height value of the i-th measurement point. Preset reference plane height; The software automatically compares the calculation results with the design allowable threshold [Δh]. When Δh... max ≤[Δh] and When the flatness is ≤0.7[Δh], the road surface is deemed to be qualified, and an inspection report containing measurement data, error curves and judgment results is generated. Preferably, a level calibrator and a laser positioner are fixed to the outer wall of the tool body. The level calibrator is a cylindrical bubble level, and its horizontal deviation is calculated according to the formula: Where θ is the horizontal deviation angle of the tool body, in rad, s is the bubble offset, and L is the effective length of the bubble tube of the level. When the radius is ≤0.005 rad, the tool body is determined to be in a horizontal measurement state; two laser positioners are provided, located on the outer ends of the tool body respectively, capable of emitting red laser beams perpendicular to the road surface, and the calibration formula for the measurement area length is: L 测 =L0+2ΔL, where L0 is the length of the tool body and ΔL is the distance between the laser emission point and the end of the tool body, used to accurately mark the start and end positions of the measurement area.

[0013] Preferably, the tool body has a charging port, a power switch, and a power display panel on its side. The charging port is a Type-C interface, which is electrically connected to the rechargeable lithium battery built into the ranging sensor. The power display panel consists of three LEDs, corresponding to high, medium, and low power states respectively. The remaining power is calculated according to the formula: Q 剩 =Q 额 ×(U 实 / U 额 ), where Q 剩 Q represents the remaining battery power. 额 For the rated capacity of lithium batteries, U 实 U represents the actual output voltage of the lithium battery. 额 The rated voltage of the lithium battery is used; the outer surface of the tool body (1) is coated with an anti-corrosion and wear-resistant coating. The wear life of the coating satisfies the formula: T=(d×ρ×S) / (f×v×t), where T is the wear life of the coating, d is the coating thickness, ρ is the coating density, S is the total area of ​​the outer surface of the tool body, f is the coefficient of friction between the coating and the outside world, v is the average daily moving speed of the tool, and t is the daily usage time of the tool. The coating thickness is 1.0-1.2mm, and the coating material is polyvinyl fluoride.

[0014] Preferably, the inner wall of the pulley mounting groove is provided with vertically arranged height adjustment holes. Adjusting bolts are threaded into the height adjustment holes, with the lower end of the adjusting bolt abutting against the side wall of the pulley's shaft. The upper end of the adjusting bolt extends to the outside of the tool body and is fixed with an anti-slip knob. The height adjustment of the pulley is adapted to the road surface slope, satisfying the formula: ΔH=L×sinα, where: ΔH is the height adjustment of the pulley, L is the distance between the axes of two adjacent apex pulleys, and α is the road surface slope angle, in rad. The relationship between the adjustment of the adjusting bolt and the pulley height adjustment satisfies: ΔH=Δs×tanβ, where Δs is the axial adjustment of the adjusting bolt, and β is the thread helix angle of the adjusting bolt, in rad. The extension height of the pulley can be adjusted by rotating the anti-slip knob, with an adjustment range of 0-10mm, thus adapting to the measurement needs of roads with different roughness and different structural layer thicknesses, ensuring that the tool body always remains horizontal.

[0015] As a preferred option, the operation process includes the following steps: Step 1: Check the tool status and confirm the remaining lithium battery charge meets the Q standard via the power display panel. 剩 ≥30%Q 额 Clean the dust and debris from the groove and track surface to ensure the ranging sensor slides smoothly, and then cover it with a dustproof protective cover. Step 2: Move the tool body to the target measurement area by pushing the pulley system. Use the laser beam emitted by the laser locator to mark the start and end positions of the measurement. Observe the bubble offset through the level calibrator. If θ > 0.005 rad, rotate the anti-slip knob to adjust the adjusting bolt. Calculate the required adjustment amount Δs according to the road slope angle α to make the tool body reach the level measurement state. Step 3: Open the dust cover, start the ranging sensor and data processing terminal, establish a wireless communication connection between the two, set the sliding speed of the ranging sensor to 0.1-0.3m / s, set the height h0 of the measurement reference plane and the design allowable threshold [Δh]; Step 4: Start the measurement program. The distance sensor slides at a constant speed along the track to collect the height data h of each measurement point on the road surface in real time. i The data is then transmitted to the data processing terminal, which automatically calculates the flatness parameters using the following formula and generates an inspection report: ; ; Step 5: Determine whether the road surface smoothness is up to standard based on the inspection report. If it is not up to standard, mark the unqualified area and record the corresponding error data. If it is up to standard, turn off the distance sensor and data processing terminal, move the tool to the next measurement area using the pulley system, and repeat steps 2-4.

[0016] Compared with the prior art, the beneficial effects of the present invention are: I. Detection efficiency has been greatly improved. This automatic road surface evenness measuring tool is equipped with a pulley system at the bottom, allowing it to quickly move to the target measurement area without manual handling or repeated positioning. The distance sensor automatically slides at a constant speed along the track, collecting road surface data in real time and transmitting it directly to the data processing terminal. This eliminates the need for manual measurement, recording, and preliminary calculation, significantly reducing the inspection time for a single area. Simultaneously, the inspection process and construction procedures can proceed in parallel, without waiting for the inspection to be completed before starting the next stage of construction. This effectively breaks down the barriers between construction and inspection, significantly improving overall construction efficiency and ensuring on-time project delivery.

[0017] II. Outstanding Detection Accuracy and Reliability This tool employs a high-precision linear guide rail in conjunction with a professional ranging sensor. The sensor's sliding trajectory is stable, and the measurement points are evenly distributed, enabling it to objectively capture minute variations in road surface unevenness and avoiding errors introduced by manual operation. The data processing terminal automatically calculates key parameters such as maximum undulation error and average error using standardized algorithms, resulting in consistent and rigorous judgments free from the uncertainties of human judgment. Accurate detection results provide a reliable basis for construction adjustments, ensuring that the flatness of each structural layer of the road surface meets design requirements. This reduces potential quality issues caused by detection deviations from the outset, improving the overall construction quality of road projects.

[0018] III. Wide range of applications and easy operation This automatic road surface evenness measurement tool is suitable for various road structure layer inspection needs. Whether it's the base and surface layers of urban roads and highways, or different construction stages of residential roads and municipal renovation projects, it can reliably perform its inspection function. The tool's overall structure is simple in design, and the operation process is easy to understand. No professional technician training is required to use it: simply move the tool to the measurement position, activate the distance sensor, and establish a connection with the terminal. It can automatically complete data collection and analysis, and the terminal will intuitively present the inspection report, allowing construction personnel to quickly obtain results and take follow-up measures. At the same time, the pulley system has good anti-slip and stable performance, allowing smooth movement on rough road surfaces or areas with gentle slopes, further expanding the tool's applicable scenarios.

[0019] IV. Construction costs are significantly reduced. This automatic road surface evenness measurement tool automates the entire inspection process, requiring only a single operator to complete all operations, significantly reducing manpower and labor costs. Accurate inspection results effectively prevent unnecessary rework due to misjudgments, reducing material waste and the time and cost of repeated construction. The tool's robust and durable structure requires only simple surface cleaning and battery checks for routine maintenance, resulting in low maintenance costs and eliminating the need for complex maintenance equipment or consumables. Long-term use can reduce construction costs in terms of manpower, materials, and time, improving the economic efficiency of engineering projects. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are explained in detail together with the embodiments of the invention, but do not constitute a limitation thereof.

[0021] Figure 1 This is a top view of the structure of the present invention; Figure 2 This is a schematic diagram of the cross-sectional structure of the present invention; Figure 3 This is a schematic flowchart of the operation method of the present invention; Figure 4 This is a system block diagram of the ranging sensor of the present invention. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1 This embodiment provides a basic automatic road surface smoothness measurement tool, suitable for smoothness detection of road surface structural layers such as conventional urban roads and residential roads. Its specific structure and usage are as follows: The tool includes a tool body 1, which is integrally cast from high-strength aluminum alloy. Its dimensions are 3000mm in length, 250mm in width, and 100mm in height under normal operating conditions. A groove 2 is formed along the length of the top of the tool body 1. The groove 2 is not through-hole; its depth is 40mm, and its width is clearance-fitted to the assembly width of the track 3. The length of the groove 2 is less than the length of the tool body 1, and a 60mm gap is left between each end of the groove 2 and the end of the tool body 1 to ensure the structural strength of the tool body 1. Tracks 3, which are high-precision linear guides, are symmetrically fixed to the inner wall of the groove 2. The length of the track 3 is exactly the same as the length of the groove 2. Limiting buffer blocks are fixed at both ends of the track 3. These buffer blocks are made of elastic polyurethane material with a thickness of 12mm and have an arc-shaped buffer surface on their inner side.

[0024] A distance measuring sensor 4 is slidably mounted on track 3. Sliding blocks adapted to track 3 are fixed on both sides of the distance measuring sensor 4. Guide grooves adapted to protrusions in track 3 are formed on the inner side of the sliding blocks, and the guide grooves are coated with grease to reduce sliding friction. The distance measuring sensor 4 has a built-in micro-drive module, which is connected to the sliding blocks for transmission. This module drives the distance measuring sensor 4 to slide at a uniform speed of 0.2 m / s along track 3. The sliding stroke is consistent with the length of track 3. During the sliding process, the distance between measurement points is 5 mm to ensure the integrity of the measurement data.

[0025] At the four corners of the bottom of the tool body 1, there is a set of pulley mounting slots 6, with four sets of pulley mounting slots 6 in total. Each pulley mounting slot 6 is rotatably connected to a pulley 5, and the four sets of pulleys 5 together form a pulley group. Wear-resistant ball bearings are fitted at both ends of the rotating shaft of each pulley 5. The outer circumference of the pulley 5 is covered with a non-slip and wear-resistant rubber sleeve with anti-slip texture. The rubber sleeve is 7mm thick, and the diameter of the pulley 5 is 55mm, ensuring that the tool moves smoothly on ordinary rough surfaces.

[0026] A dustproof cover can be detachably installed at the groove 2 opening of the tool body 1. The cover is made of transparent polycarbonate material, and its length is the same as that of the groove 2. The edge is provided with a buckle structure, which is fixed to the edge of the groove 2 by buckling. The inner surface of the cover is covered with a 2.5mm thick dustproof velvet layer, which can effectively prevent construction dust and debris from entering the groove 2 and contaminating the track 3 and the distance sensor 4.

[0027] A level calibrator and a laser locator are fixed to the outer wall of the tool body 1. The level calibrator is a cylindrical bubble level, and there are two laser locators located at the outer ends of the tool body 1, emitting red laser beams perpendicular to the road surface. The side of the tool body 1 has a Type-C charging port, a power switch, and a power display panel. The power display panel consists of three LEDs, corresponding to high, medium, and low power levels, and is electrically connected to the rechargeable lithium battery built into the distance sensor 4. The entire outer surface of the tool body 1 is coated with a 1.1mm thick polyvinyl fluoride anti-corrosion and wear-resistant coating.

[0028] Before use, first check the battery level display panel to confirm that the remaining lithium battery power meets the usage requirements. Clean the dust and debris from the surface of the groove 2 and track 3 to ensure that the distance sensor 4 slides smoothly, and then cover it with the dustproof cover. Move the tool body 1 to the target measurement area by pushing it with the pulley system. Use the laser beam emitted by the laser locator to mark the start and end positions of the measurement. Observe the bubble offset using the level calibrator. If the horizontal deviation angle exceeds 0.005 rad, rotate the anti-slip knob of the adjusting bolt in the pulley mounting groove 6 to adjust the extension height of the pulley 5 so that the tool body 1 is in a horizontal measurement state.

[0029] Open the dust cover, start the distance sensor 4 and the smartphone (data processing terminal), establish a wireless communication connection between the two via Bluetooth 5.0, set the sliding speed of the distance sensor 4 to 0.2 m / s, and set the measurement reference surface height h0 and the design allowable threshold [Δh]. After starting the measurement program, the distance sensor 4 slides at a constant speed along the track 3, collecting the height data h of each measurement point on the road surface in real time. i The data is then transmitted to a smartphone, where the built-in road surface evenness analysis software uses formulas... The maximum fluctuation error is calculated using the formula. The system calculates the average error, automatically compares it with the design allowable threshold [Δh], and generates a test report containing measurement data, error curves, and judgment results.

[0030] After the inspection is completed, if the road surface flatness is acceptable, turn off the distance sensor 4 and the smartphone, and move the tool to the next measurement area using the pulley system, repeating the above operation; if it is unacceptable, mark the unacceptable area and record the error data. After all measurements are completed, turn off the power switch, thoroughly clean the dirt from the tool body 1, track 3, distance sensor 4, and pulley 5, cover with the dustproof protective cover, and store the tool in a dry and ventilated environment. If the remaining battery power is less than 20% of the rated capacity, charge it to full power through the Type-C charging port.

[0031] Example 2 This embodiment provides an anti-interference automatic road surface smoothness measurement tool, suitable for scenarios such as highway construction projects and municipal road reconstruction projects with high construction dust and rough road surfaces. Its specific structure and usage are as follows: The tool includes a tool body 1, which is integrally cast from high-strength aluminum alloy. Its dimensions are 3000mm in length, 250mm in width, and 100mm in height under normal operating conditions. A non-through groove 2 is formed along the length of the top of the tool body 1. The groove 2 is 38mm deep and its width is fitted with the assembly width of the track 3. The length of the groove 2 is less than the length of the tool body 1, and each end is 55mm away from the end of the tool body 1, balancing measurement coverage and structural stability.

[0032] The inner wall of the groove 2 is symmetrically fixed with a track 3, which is a high-precision linear guide rail with the same length as the groove 2. The limiting buffer blocks at both ends of the track 3 are thickened to 15mm, and the elastic polyurethane material has higher hardness, which can effectively resist the impact force during the sliding process of the distance sensor 4. The distance sensor 4 is slidably mounted on the track 3. The guide grooves of the sliding blocks on both sides of the distance sensor 4 are coated with high-viscosity grease, which can maintain the lubrication effect in dusty environments. The built-in micro drive module of the distance sensor 4 can drive it to slide at a uniform speed of 0.15m / s along the track 3. The sliding stroke is the same as the length of the track 3, and the distance between measurement points is reduced to 3mm, improving the measurement accuracy.

[0033] Four sets of pulley mounting slots 6 are provided at the four top corners of the bottom of the tool body 1. Each set of pulley mounting slots 6 is rotatably connected to a pulley 5, forming a basic pulley group. The wear-resistant ball bearings sleeved at both ends of the shaft of the pulley 5 adopt a sealed design to prevent dust from entering and affecting rotation. The anti-slip and wear-resistant rubber sleeve covering the outer circumference of the pulley 5 is 8mm thick, and the surface anti-slip texture is cross-shaped. The diameter of the pulley 5 is 60mm, which increases the contact area with the road surface and ensures that the tool can move smoothly on high roughness surfaces, avoiding measurement errors caused by bumps.

[0034] The dustproof protective cover installed at the groove opening of groove 2 has a sealing strip on its edge, which fits tightly with the edge of groove 2. The dustproof velvet layer on the inner surface of the protective cover is 3mm thick, which has a better dustproof effect and can effectively prevent a large amount of dust from entering the interior of groove 2 during construction, thus protecting the normal operation of track 3 and distance sensor 4.

[0035] The leveling device fixed to the outer wall of the tool body 1 is a high-sensitivity cylindrical bubble level. The red laser beam emitted by the laser positioner has a wavelength of 650nm, providing strong penetration and clearly marking the start and end positions of the measurement area even in strong light. The Type-C charging port on the side of the tool body 1 is equipped with a dust plug, and the LED lights on the power display panel are brighter, making it easy to quickly check the power status on the construction site. The 1.1mm thick polyvinyl fluoride anti-corrosion and wear-resistant coating on the outer surface of the tool body 1 has a frosted finish to reduce scratches and damage during construction.

[0036] The data processing terminal uses a dedicated engineering tablet. Its built-in road surface evenness analysis software, in addition to basic error calculation and pass / fail determination functions, also supports real-time error curve plotting and measurement data classification and storage. It can export inspection reports to PDF format for easy project archiving. The distance sensor 4 establishes a wireless communication connection with the dedicated tablet via Wi-Fi 6, resulting in faster transmission speeds, stronger anti-interference capabilities, and avoiding the impact of dust and electromagnetic fields on data transmission.

[0037] Before use, first check whether the dust cover of the tool body 1 is tightly sealed and whether the rubber sleeve of the pulley 5 is intact. Confirm that the remaining power is ≥30% of the rated capacity through the power display panel. After cleaning the dust from the surface of the track 3, replace the protective cover. Push the tool body 1 to the target measurement area, mark the measurement range using the laser locator, and calibrate the level of the tool body 1 using the level calibrator. If the horizontal deviation angle corresponding to the bubble offset exceeds the threshold, adjust the height of the pulley 5 by rotating the adjusting bolt in the pulley mounting slot 6 until a level measurement state is achieved.

[0038] Open the protective cover, activate the ranging sensor 4 and the dedicated tablet, establish a Wi-Fi 6 connection, set the measurement parameters, and start the measurement program. The ranging sensor 4 slides along the track 3 at a uniform speed to collect data. The tablet receives and calculates the maximum fluctuation error and average error in real time, generating a test report. If there is a lot of dust during the test, keep the protective cover partially open and use the dustproof cloth layer to block dust and ensure that the measurement is not interfered with. After the measurement is completed, clean the tools as required and store them to ensure reliability for the next use.

[0039] Example 3 This embodiment provides a highly adaptable automatic road surface smoothness measurement tool, suitable for smoothness detection in special scenarios such as mountain roads with large slopes and significant differences in structural layer thickness, and highway ramps. Its specific structure and usage are as follows: The tool includes a tool body 1, which is integrally cast from high-strength aluminum alloy. Its dimensions are 3000mm in length, 250mm in width, and 100mm in height under normal operating conditions. A non-through groove 2 is formed along the length of the top of the tool body 1. The groove 2 is 45mm deep and its width is fitted with the assembly width of the track 3. The length of the groove 2 is less than the length of the tool body 1, and each end is 70mm away from the end of the tool body 1 to enhance the structural stability of the tool body 1 when used on sloping surfaces.

[0040] The inner wall of the groove 2 is symmetrically fixed with a track 3, which is a high-precision linear guide rail with the same length as the groove 2. The limiting buffer blocks at both ends of the track 3 are 14mm thick, and the elastic coefficient of the elastic polyurethane material has been optimized to meet the buffering requirements of the ranging sensor 4 at different sliding speeds. The ranging sensor 4 is slidably mounted on the track 3. The sliding blocks on both sides of the ranging sensor 4 are made of wear-resistant alloy material, and the guide groove is coated with high-temperature resistant grease to suit the use environment with large temperature differences in mountainous roads. The built-in micro drive module of the ranging sensor 4 can drive it to slide at a uniform speed of 0.25m / s along the track 3. The sliding stroke is the same as the length of the track 3, and the distance between the measurement points is 4mm, which balances measurement efficiency and accuracy.

[0041] The tool body 1 has four sets of pulley mounting slots 6 at its four corners. To adapt to sloping surfaces, two additional sets of pulley mounting slots 6 are added to the central area of ​​the bottom surface between the four corner slots 6, for a total of six sets of pulley mounting slots 6. Each set of pulley mounting slots 6 is rotatably connected to a pulley 5, forming a six-wheel pulley system. High-strength wear-resistant ball bearings are fitted at both ends of the axle of all pulleys 5. The outer circumference of the pulleys 5 is covered with a non-slip, wear-resistant rubber sleeve with a thickness of 7mm and anti-slip protrusions on the surface. The diameter of the pulleys 5 is 58mm. The six-wheel distribution design makes the tool more stable on sloping surfaces and avoids the risk of tipping over.

[0042] The inner wall of the pulley mounting groove 6 has vertically arranged height adjustment holes. Adjustment bolts are threaded into these holes, with the lower end abutting against the side wall of the pulley 5's rotating shaft, and the upper end extending to the outside of the tool body 1 and fixed with an anti-slip knob. Rotating the anti-slip knob adjusts the extension height of the pulley 5, with an adjustment range of 0-10mm, adapting to road surface measurement needs with different slopes and structural layer thicknesses, ensuring that the tool body 1 always remains horizontal.

[0043] The horizontal calibrator fixed to the outer wall of the tool body 1 is a cylindrical bubble level with an effective bubble tube length of 100mm, providing higher accuracy in calculating horizontal deviation. When the road surface slope is large, the horizontal calibrator can accurately detect the horizontal state of the tool body 1. Combined with the height adjustment function of the pulley 5, it can be quickly adjusted to a horizontal measurement state. Two laser positioners are set, located on the outer ends of the tool body 1 respectively. The emitted red laser beam is perpendicular to the road surface. The length of the measurement area can be accurately calibrated using the formula Lmeasured = L0 + 2ΔL, where L0 is the length of the tool body 1 (3000mm), and ΔL is the distance between the laser emission point and the end of the tool body 1 (50mm), ensuring accurate marking of the measurement area.

[0044] The side of the tool body 1 features a Type-C charging port, a power switch, and a power display panel. The charging port supports fast charging, allowing for quick power replenishment and making it suitable for scenarios where charging is inconvenient, such as construction sites on mountainous roads. The three LEDs on the power display panel correspond to three states: ≥70% (high), 30%-70% (medium), and <30% (low). The remaining power is indicated by the formula Q. 剩 =Q 额 ×U 实 / U 额 Precise calculations allow operators to easily determine whether charging is needed. The entire outer surface of the tool body 1 is coated with a 1.2mm thick polyvinyl fluoride anti-corrosion and wear-resistant coating, which extends its wear resistance and lifespan, meeting the long-term, high-frequency measurement needs of mountain road engineering projects.

[0045] The ranging sensor 4 establishes a wireless communication connection with the data processing terminal (smartphone or dedicated tablet) via a 4G / 5G network module, ensuring stable data transmission even in mountainous areas with weak signals. The terminal's built-in road surface smoothness analysis software can flexibly set the design allowable threshold [Δh] according to the design requirements of mountain roads. After calculating the maximum undulation error and average error using formulas, it automatically compares and determines whether the road surface smoothness is up to standard. The generated inspection report can be uploaded to the engineering management platform in real time, facilitating remote monitoring of construction quality.

[0046] Before use, first check if the adjusting bolts of the six sets of pulleys 5 are flexible and if the protective covers are intact. Confirm that the remaining power is sufficient for measurement using the power display panel. Adjust the height of the pulleys 5 according to the road slope, push the tool body 1 to the target measurement area, mark the start and end positions of the measurement using a laser locator, observe the bubble offset using a level calibrator, and calculate the horizontal deviation angle. If it exceeds 0.005 rad, calculate the required pulley height adjustment using the formula ΔH=L×sinα based on the road slope angle α. Then calculate the axial adjustment amount Δs of the adjusting bolts using the formula ΔH=Δs×tanβ. Rotate the anti-slip knob to complete the precise adjustment, ensuring the tool body 1 is in a horizontal measurement state.

[0047] Open the protective cover, start the ranging sensor 4 and data processing terminal, establish a 4G / 5G network connection, and set the sliding speed of the ranging sensor 4, the height h0 of the measurement reference surface, and the design allowable threshold [Δh]. After starting the measurement program, the ranging sensor 4 slides at a constant speed along the track 3, collects the height data of each measurement point on the road surface, and transmits it to the terminal. The terminal automatically calculates the flatness parameters and generates a test report. If it is unqualified, the unqualified area is marked and the error data is recorded; if it is qualified, the tool is moved to the next measurement area and the operation is repeated. After the measurement is completed, clean all parts of the tool, adjust the pulley 5 to the initial height, cover it with the protective cover, and store it in a dry and ventilated environment. If the remaining power is low, charge it in time.

[0048] The automatic road surface smoothness measurement tool of the present invention has the following advantages: I. Detection efficiency has been greatly improved. This automatic road surface evenness measuring tool is equipped with a pulley system at the bottom, allowing it to quickly move to the target measurement area without manual handling or repeated positioning. The distance sensor automatically slides at a constant speed along the track, collecting road surface data in real time and transmitting it directly to the data processing terminal. This eliminates the need for manual measurement, recording, and preliminary calculation, significantly reducing the inspection time for a single area. Simultaneously, the inspection process and construction procedures can proceed in parallel, without waiting for the inspection to be completed before starting the next stage of construction. This effectively breaks down the barriers between construction and inspection, significantly improving overall construction efficiency and ensuring on-time project delivery.

[0049] II. Outstanding Detection Accuracy and Reliability This tool employs a high-precision linear guide rail in conjunction with a professional ranging sensor. The sensor's sliding trajectory is stable, and the measurement points are evenly distributed, enabling it to objectively capture minute variations in road surface unevenness and avoiding errors introduced by manual operation. The data processing terminal automatically calculates key parameters such as maximum undulation error and average error using standardized algorithms, resulting in consistent and rigorous judgments free from the uncertainties of human judgment. Accurate detection results provide a reliable basis for construction adjustments, ensuring that the flatness of each structural layer of the road surface meets design requirements. This reduces potential quality issues caused by detection deviations from the outset, improving the overall construction quality of road projects.

[0050] III. Wide range of applications and easy operation This automatic road surface evenness measurement tool is suitable for various road structure layer inspection needs. Whether it's the base and surface layers of urban roads and highways, or different construction stages of residential roads and municipal renovation projects, it can reliably perform its inspection function. The tool's overall structure is simple in design, and the operation process is easy to understand. No professional technician training is required to use it: simply move the tool to the measurement position, activate the distance sensor, and establish a connection with the terminal. It can automatically complete data collection and analysis, and the terminal will intuitively present the inspection report, allowing construction personnel to quickly obtain results and take follow-up measures. At the same time, the pulley system has good anti-slip and stable performance, allowing smooth movement on rough road surfaces or areas with gentle slopes, further expanding the tool's applicable scenarios.

[0051] IV. Construction costs are significantly reduced. This automatic road surface evenness measurement tool automates the entire inspection process, requiring only a single operator to complete all operations, significantly reducing manpower and labor costs. Accurate inspection results effectively prevent unnecessary rework due to misjudgments, reducing material waste and the time and cost of repeated construction. The tool's robust and durable structure requires only simple surface cleaning and battery checks for routine maintenance, resulting in low maintenance costs and eliminating the need for complex maintenance equipment or consumables. Long-term use can reduce construction costs in terms of manpower, materials, and time, improving the economic efficiency of engineering projects.

[0052] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An automatic tool for measuring road surface smoothness, comprising a tool body (1), wherein a groove (2) is formed on the top of the tool body (1) along its length direction, characterized in that, The inner wall of the groove (2) is symmetrically fixed with a track (3), and a distance measuring sensor (4) for accurately collecting road surface bump data is slidably mounted on the track (3); a set of pulley mounting slots (6) are respectively provided at the four top corners of the bottom of the tool body (1), and the number of pulley mounting slots (6) is not less than four sets. Each pulley mounting slot (6) is rotatably connected with a pulley (5), and all the pulleys (5) together form a pulley group for tool movement; The distance sensor (4) establishes a signal connection with the external data processing terminal. After the tool body (1) is driven to move quickly to the target measurement position by the pulley group, the distance sensor (4) slides at a constant speed along the track (3) to collect the flatness data of each structural layer of the road surface in real time and transmit it to the data processing terminal. After the terminal analyzes the data, it outputs the road surface flatness error value to realize the automated measurement of road surface flatness.

2. The automatic road surface smoothness measuring tool according to claim 1, characterized in that, The tool body (1) is integrally cast from high-strength aluminum alloy. Its external dimensions are as follows: length 3000mm, width 250mm, height 100mm under normal working conditions. The depth of the groove (2) is 35-45mm, and the width is matched with the assembly width of the track (3). The length of the groove (2) is less than the length of the tool body (1). The two ends of the groove (2) are 50-80mm apart from the ends of the tool body (1). The length of the track (3) is completely consistent with the length of the groove (2), ensuring that the measurement coverage of the distance sensor (4) matches the effective measurement span of the tool body (1).

3. The automatic road surface smoothness measuring tool according to claim 1, characterized in that, The pulley assembly consists of at least four sets of pulleys (5). The four sets of pulleys (5) are fitted into the pulley mounting slots (6) at the four corners of the bottom of the tool body (1). If additional pulleys (5) are provided, they are evenly distributed in the middle area of ​​the bottom surface between the four corner pulleys (5). Each pulley (5) has wear-resistant ball bearings fitted at both ends of its shaft, and the outer circumference of the pulley (5) is covered with a non-slip and wear-resistant rubber sleeve. The surface of the rubber sleeve has non-slip textures, the thickness of the rubber sleeve is 6-8mm, and the diameter of the pulley (5) is 50-60mm, ensuring that the tool can move smoothly on rough surfaces.

4. The automatic road surface smoothness measuring tool according to claim 1, characterized in that, The distance sensor (4) has sliding blocks that are adapted to the track (3) fixed on both sides. The inner side of the sliding block is provided with a guide groove that is adapted to the protrusion of the track (3). The guide groove is coated with grease. The distance sensor (4) has a built-in micro drive module. The drive module is connected to the sliding block and can drive the distance sensor (4) to slide at a uniform speed of 0.1-0.3m / s along the track (3). The sliding stroke is consistent with the length of the track (3). During the sliding process, the distance between the measuring points of the distance sensor (4) is not greater than 5mm. The track (3) is a high-precision linear guide. Both ends of the track (3) are fixed with limit buffer blocks. The limit buffer blocks are made of elastic polyurethane material with a thickness of 10-15mm. The limit buffer blocks are set corresponding to the ends of the distance sensor (4). The inner side of the limit buffer block is provided with an arc-shaped buffer surface to limit the sliding limit position of the distance sensor (4) and avoid rigid collision damage.

5. The automatic road surface smoothness measuring tool according to claim 1, characterized in that, A dustproof cover can be detachably installed at the opening of the groove (2). The cover is made of transparent polycarbonate material. The length of the cover is the same as the length of the groove (2). The edge of the cover is provided with a buckle structure, which is fixed to the edge of the groove (2) by buckling. The inner surface of the cover is covered with a dustproof velvet layer with a thickness of 2-3mm, which can prevent construction dust and debris from entering the groove (2) and contaminating the track (3) and the distance sensor (4).

6. The automatic road surface smoothness measuring tool according to claim 1, characterized in that, The distance sensor (4) is connected to the data processing terminal via wireless communication, specifically including Bluetooth 5.0, Wi-Fi 6, or 4G / 5G network modules. The data processing terminal is a smartphone or a dedicated tablet, and the terminal has built-in road surface smoothness analysis software. The analysis software calculates the road surface smoothness parameters using the following formula: Maximum fluctuation error: Δh max =h max -h min , where h max h is the maximum height value among all measurement points collected by the distance sensor (4). min The minimum height value among all measurement points; Average error: ,in The total number of measurement points. Let i be the height value of the i-th measurement point. Preset reference plane height; The software automatically compares the calculation results with the design allowable threshold [Δh]. When Δh... max ≤[Δh] and When the flatness is ≤0.7[Δh], the road surface is deemed to be qualified, and an inspection report containing measurement data, error curves and judgment results is generated.

7. The automatic road surface smoothness measuring tool according to claim 1, characterized in that, The outer wall of the tool body (1) is fixed with a level calibrator and a laser positioner. The level calibrator is a cylindrical bubble level, and its horizontal deviation is calculated according to the formula: Where θ is the horizontal deviation angle of the tool body (1), in rad, s is the bubble offset, and L is the effective length of the bubble tube of the level. When the value is ≤0.005rad, the tool body (1) is determined to be in a horizontal measurement state; two laser positioners are provided, located on the outer sides of both ends of the tool body (1), and can emit red laser beams perpendicular to the road surface. The calibration formula for the measurement area length is: L 测 =L0+2ΔL, where L0 is the length of the tool body (1) and ΔL is the distance between the laser emission point and the end of the tool body (1), used to accurately mark the start and end positions of the measurement area.

8. The automatic road surface smoothness measuring tool according to claim 1, characterized in that, The tool body (1) has a charging port, a power switch and a power display panel on its side. The charging port is a Type-C interface, which is electrically connected to the rechargeable lithium battery built into the ranging sensor (4). The power display panel consists of three LEDs, which correspond to high, medium and low power states respectively. The remaining power is calculated according to the formula: Q 剩 =Q 额 ×(U 实 / U 额 ), where Q 剩 Q represents the remaining battery power. 额 For the rated capacity of lithium batteries, U 实 U represents the actual output voltage of the lithium battery. 额 The rated voltage of the lithium battery is used; the outer surface of the tool body (1) is coated with an anti-corrosion and wear-resistant coating. The wear life of the coating satisfies the formula: T=(d×ρ×S) / (f×v×t), where T is the wear life of the coating, d is the coating thickness, ρ is the coating density, S is the total area of ​​the outer surface of the tool body (1), f is the coefficient of friction between the coating and the outside world, v is the average daily moving speed of the tool, and t is the daily usage time of the tool. The coating thickness is 1.0-1.2mm, and the coating material is polyvinyl fluoride.

9. The automatic road surface smoothness measuring tool according to claim 1, characterized in that, The inner wall of the pulley mounting groove (6) is provided with vertically arranged height adjustment holes. The height adjustment holes are threaded with adjustment bolts. The lower end of the adjustment bolts abuts against the side wall of the shaft of the pulley (5). The upper end of the adjustment bolts extends to the outside of the tool body (1) and is fixed with an anti-slip knob. The height adjustment of the pulley (5) is adapted to the road slope and satisfies the formula: ΔH=L×sinα, where: ΔH is the height adjustment of the pulley (5), L is the distance between the axes of two adjacent apex pulleys (5), and α is the road slope angle, in rad. The relationship between the adjustment of the adjustment bolt and the height adjustment of the pulley satisfies: ΔH=Δs×tanβ, where Δs is the axial adjustment of the adjustment bolt, and β is the thread helix angle of the adjustment bolt, in rad. The extension height of the pulley (5) can be adjusted by rotating the anti-slip knob. The adjustment range is 0-10mm, which can adapt to the road measurement needs of different roughness and different structural layer thicknesses, and ensure that the tool body (1) always remains horizontal.

10. The automatic road surface smoothness measuring tool according to any one of claims 1-9, characterized in that, Its operation process includes the following steps: Step 1: Check the tool status and confirm the remaining lithium battery charge meets the Q standard via the power display panel. 剩 ≥30%Q 额 Clean the dust and debris from the surface of the groove (2) and track (3) to ensure that the distance sensor (4) slides smoothly, and cover it with a dustproof protective cover; Step 2: Push the tool body (1) through the pulley system to move the tool to the target measurement area. Use the laser beam emitted by the laser locator to mark the start and end positions of the measurement. Observe the bubble offset through the level calibrator. If θ > 0.005 rad, rotate the anti-slip knob to adjust the adjusting bolt. Calculate the required adjustment amount Δs according to the road slope angle α so that the tool body (1) reaches the horizontal measurement state. Step 3: Open the dust cover, start the ranging sensor (4) and the data processing terminal, establish a wireless communication connection between the two, set the sliding speed of the ranging sensor (4) to 0.1-0.3m / s, set the height of the measurement reference plane h0 and the design allowable threshold [Δh]; Step 4: Start the measurement program. The distance sensor (4) slides at a constant speed along the track (3) to collect the height data h of each measurement point on the road surface in real time. i The data is then transmitted to the data processing terminal, which automatically calculates the flatness parameters using the following formula and generates an inspection report: ； ； Step 5: Determine whether the road surface smoothness is up to standard based on the test report. If it is not up to standard, mark the unqualified area and record the corresponding error data. If it is up to standard, turn off the distance sensor (4) and the data processing terminal, and move the tool to the next measurement area through the pulley group. Repeat steps 2-4.

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